Stella 125 Automatica CVT
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Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Feb 07, 2019 3:44 pm quote
I picked up a Stella cvt for free which isn't running great. I figure I'll start this thread to track my issues and solutions as i progress, since there isn't much info out there about these models. Issues noticed right off the bat is an ecu warning for engine temp sensor which seems to be common and not critical to running. I bought a replacement anyways but never installed cause it required removing engine from frame.


First steps to get it running...cleaned the carb, changed the air filters and fuel filters and got it running for a short period. Drove it around for half an hour and it smelled like burning plastic. Took it back to my garage and shut it down and it wouldn't start again.

So then i tried replacing the ht coil which i assume was the burning plastic smell. This led it to start again and run on kickstand for half an hour. Next, i tried to dial in the carb correctly, attached a cheap tachometer and set it to what the idle the service manual said to. Then messed with the idle adjustment screw following next steps of the manual. Then moved on to the air fuel mix screw step in manual. At this point the idle went haywire revving uncontrollably fast. So i turned it off and reset it. After that it wouldn't start again for weeks.

I figure it is a little bit of a carb setting issue and possibly something else like valve clearances. This week went back to messing with it and got it to start again by opening up the air fuel mix screw slowly until it started, but idling strange still. Once it warms up it either dies or revs really high to the point of sliding the scooter on its kickstand along the ground.

Next i went to check compression but given the awkward placement of the engine shrowd, i lost the compression test spark plug hole attachment into the ether of the magneto fan. This required removing the engine from frame to take the engine cover off. So this is where I am currently at, with the engine out of frame, shrowd off and recovered that stupid brass part!

Now that engine is out and accessible, i decided to check valve clearances and replace that engine temperature sensor. Service manual says to align the marks on the cam sprocket parallel to the open case where the head cover goes on, then make sure the marks on the magneto line up with the Mark on the engine case. I've got it lined up on the cam sprocket correctly and have checked the clearances, which the inlet valve is a bit loose, and the exhaust valve is a bit tight. Unfortunately the marks on the magneto are strangely not exactly where they should be. There are 4 marks on the magneto in two groups of two. When the cam sprocket is lined up correctly, there are two marks on the magneto at 12 o clock, and two near the engine case mark around 10 o clock, but they are about half an inch above the case mark which is at about 9 o clock. Those two marks closest to the case mark have labels, one is "r" (which is the further away closest to midnight) and one that is marked "t" which is closest to the case mark. I am wondering if these can be/need to be set correctly in line with the case Mark and if so, which one goes at that mark.

Either way, for now i will adjust the valve clearances to spec.

IMG_20190207_121536.jpg
Frame with no engine!

IMG_20190207_121528.jpg
engine extracted!

IMG_20190207_125847.jpg
fan cover off. Brass part rescued from the ether.

IMG_20190207_135631_01.jpg
New engine temp sensor installed. Just gotta find a solution for the snap connector to the sensor cable. This replacement came bare no connector.

IMG_20190207_122749.jpg
Who would have thought this scoot is only 4 years old, from the look of that pipe. Lived all its life outside on the streets of nyc.

IMG_20190207_164448_01.jpg
cylinder head cover removed.

IMG_20190207_162054.jpg
another view of the internals.

IMG_20190207_165207_01.jpg
Cam sprockets lined up correctly for valve clearance check.

IMG_20190207_165320.jpg
marks on the magneto.. one set of 2 at the top, one set of two around 10pm just above the case mark. the top mark on the magneto left says "r", the bottom one says "t". neither line up correctly with the case mark.



Last edited by swiss1939 on Thu Feb 07, 2019 8:17 pm; edited 2 times in total
Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3187
Location: Oceanside/ SF
Thu Feb 07, 2019 4:26 pm quote
Ive never seen one of those close up. Looking forward to your pics.

If its carb’d and revving sky high have you checked for air leaks at the carb, manifold, or exhaust? If its anything like a smallframe vespa with those 3 bolting to the cases, it may be worth putting some semi liquid gasket sealant at any possible air leak points.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Feb 07, 2019 4:30 pm quote
Parts are scarce for it which sucks. Definitely needs a new exhaust and exhaust down pipe as it's only 4 yrs old and they are rusted like a 30 yr old pipe. I was questioning the integrity of the vacuum hoses and am gonna replace all the hoses while everything is out of the frame.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Feb 07, 2019 8:05 pm quote
So this scooter also has a fuel resevoir tank at the base of the seat, above the gas tank. The way it works is the fuel gets fed through a filter up from the tank to the resevoir with a pump, once up in the resevoir, it is gravity fed from the resevoir down through a filter to the carb. The resevoir has an overflow that feeds back into the gas tank filling neck, so that the pump keeps filling the resevoir, regardless of if it goes to the carb or the overflow back into the gas tank. I guess it's something to do with consistent flow of fuel, cause the fuel pump spits it out in a pulsing stream instead of constant flow.

This resevoir does have some white corrosion around the base, which makes me wonder if maybe the resevoir tank has a microscopic leak? One thing i've noticed about this scoot that I haven't figured out yet is there is some dampness along the side of the tire and ground below the engine that looks to be some sort of non water soluble fluid. Its like a spray bottle misting the surface of the tire and ground. This wet area then crystalizes when dry, so that the ground and tire have a white crystal coating on it after sitting in one spot for the past couple months. I'm hoping its related to the white corrosion on this resevoir tank but who knows!

IMG_20190207_132647.jpg
fuel resevoir tank corrosion.. is it a leak?

IMG_20190207_132702.jpg
another view of the white corrosion at the base of the fuel resevoir.

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Feb 07, 2019 8:11 pm quote
And here is a list of other cosmetic and non engine related issues when I received it. All need to be resolved, but am preoccupied with getting the engine issues sorted out first.

1. all locks were destroyed as the original owner had it parked outside on the streets of nyc for its whole life. The glove box latch and lock were destroyed, I fixed that already. I tried to install the ignition lock but put it in wrong direction which prevented the steering lock from turning correctly, so I had to drill that new lock out, and just haven't put the other new one in yet.

2. front shock is worthless. On my first and only ride with this scoot, it bottomed out on every bump. New shock already received and waiting to be installed.

3. chrome trim on the leg shield was ripped up on one side, again most likely from someone messing with the scoot parked out on nyc streets. Black plastic trim in hand waiting to be installed.
Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3187
Location: Oceanside/ SF
Fri Feb 08, 2019 9:22 pm quote
You’ll know if your valves are set correctly when you try to start it. If it runs then you found TDC and adjusted accordingly.

Does the fuel pump run off a vacuum created by the piston? I know the vacuum fuel taps run off suction. The pulsing fuel could be in time with the stroke.

Was there any battery acid spilled by that reservoir? Maybe its just NY oxidation from being outside?
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Fri Feb 08, 2019 11:16 pm quote
I believe the pump does run off vacuum from the head. As far as battery acid spilled by the reservoir, no clue. I wanna say I doubt it's battery acid as the battery is nowhere near it, but it could be some liquid spilled or pooled there over time given how the under seat engine cover wraps around the reservoir which sticks out. Possibly salt from melted snow and street salt over years.

The guy I got it from was original owner and really was hands off owner, didn't care much to elaborate on service other than he had it serviced and just didn't want to deal with it anymore with the issues it had, basically just wanted it gone. All I cared about was "free" and the valid paperwork was there!
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Sat Feb 09, 2019 9:56 am quote
I figured it best to stick with lining up the T mark on the magneto with the case mark, and the cam sprocket marks would lay wherever they are at that point. This seems to be the correct TDC point as once I set everything there, the cam sprocket marks were lining up with the ground instead of the angled head case. Inlet valve clearance was a bit loose and the exhaust valve was too tight. These are the correct settings versus what they were at when checked.

correct:
Inlet - 0.08mm +/- 0.01mm
Exhaust - 0.10mm +/- 0.01mm

actual clearances as checked:
Inlet - 0.10mm
Exhaust - 0.08mm

These have been corrected. Hopefully those minor changes make a huge difference in how this runs.

The engine temp sensor wire has a snap connector that I am trying to find a mate for, to wire up to the new temp sensor which is bare wires. Anyone recognize this connector pictured, and or where to get something like it?

IMG_20190209_123359.jpg
original connector next to the new sensor bare wires.

IMG_20190209_123410.jpg

IMG_20190209_123436.jpg

Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3187
Location: Oceanside/ SF
Mon Feb 11, 2019 4:17 pm quote
No idea where to find that exact quick connector. Since youre not messing with it all the time i'd say cut and solder in some common spade connectors in case you ever need to disconnect, or just solder the wires together and insulate it.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Feb 21, 2019 6:35 pm quote
Yeah that's what I did, but I was hoping to find the original part. Gave up looking and went the easy route.
Hooked
'04 Stella 2T GB150 '15 Genuine Roughhouse 50 '17 Kawasaki Versys 650
Joined: 08 Jun 2012
Posts: 348
Location: Philadelphia
Fri Feb 22, 2019 4:39 am quote
I have no idea why LML went with this engine design, rather than sourcing a GY6 engine and modifying it to fit in the LML frame.

It was a great idea, since many people admired the Stella, and asked for it in twist and go. What sunk the 125 auto was the fact that it was only 125cc's (should have been at least 200), and that weird engine design which made it difficult to work on.

such a shame.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Fri Mar 01, 2019 7:14 pm quote
Finally got around to installing the new ignition lock and glove box lock to fix the ones destroyed from people trying to break into it parked in NYC.

Completed the valve clearance adjustments, kindof damaged the aluminum cover because i read the wrong torque settings in the repair manual and tightened too much till the bolts sunk into the aluminum cover. Still works fine, but gonna try to fill those recesses in with jb weld and replace the bolts.

Gave up on trying to find the original connector for the engine temp sensor. Just stripped and added tab connectors.

Also started replacing all the old cracked vacuum lines with silicone replacements. Just waiting on a 4mm hose to replace one smaller line.

Should hopefully get the engine back into frame and try to start it up again in a week or two.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Tue Mar 05, 2019 2:54 pm quote
So i filled in the damage to the head I caused by tightening the head bolts too much, replaced bolts with new and reinstalled. Not sure the jb weld was necessary or worked seeing as once I tightened it down after setting for a day, jb weld started popping off. Either way, the head cover is back on after making those valve adjustments.

I then started looking at all the wires coming out of the engine and frame which I disconnected to pull the engine out to start figuring out where everything goes back (seeing as I did not take pictures of everything at the time). I ran across some interesting issues during this process which I am wondering if that may have been the problem causing stalling and poor running conditions all along, straight from factory! the wiring from the two sensors on the engine have two different connectors, one fancy unique one, which upon further examination was confusing me as the wiring colors for those mated connectors on the ECU side didn't seem correct compared to the wiring diagram. I unplugged the ECU connector and ran some continuity tests to those sensor connectors and confirmed, the factory wired up the engine temp sensor to the lambda sensor pins on ECU and vice versa!

So the whole life of this scooter, the engine temp and lambda sensors were reversed on the ECU end. In addition, the engine temp sensor I replaced because I was getting an error code for that sensor on power on. Now I know that since they were reversed, the lambda sensor was the actual thing broken, not the engine temp sensor. So the ECU was getting no temperature results for the engine sensor readings, given the lambda sensor is broken, and exhaust temp readings coming from the engine sensor.

I am wondering if anyone knows how to remove either of these multi connectors and swap them? Since I have them, I dont want to waste them, just want to switch them.

IMG_20190305_165056.jpg
The lambda sensor connector is this unique one, whose mate on the ECU side, has a green wire, and matches up to the engine temp sensor pin on the ECU.

IMG_20190305_165308.jpg
the normal 2 pin connector in center of image is the wire coming from engine temp sensor, and i am holding the connector coming from the exhaust sensor. My goal is to swap these two connectors on this end, if anyone knows a way to do it without some spec

IMG_20190305_165245.jpg
and here are the ECU side connectors, green wire with unique connector should not be going to the exhaust sensor as it is currently set up.

WIRING_DIAGRAM_LML_CVT.jpg
engine temp sensor is a green wire, lambda sensor is a brown wire. not so in how my bike is wired up.



Last edited by swiss1939 on Tue Mar 05, 2019 10:42 pm; edited 1 time in total
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Tue Mar 05, 2019 10:29 pm quote
On closer inspection of the wiring diagram for this bike, being able to look at it much larger on my desktop instead of cell phone in the garage, I am further confused whether the wiring was wrong from factory or if the wiring diagram is wrong in printing...

The CHT sensor is clearly labeled as "NTC" and depicted with dark green wire.

The Lambda sensor is clearly labeled as "Lambda Sensor" and depicted with brown wire.

On the ECU side of the wiring diagram everything gets confusing:

pin#3 is shown as the dark green wire connecting from the engine sensor (NTC) depicted, but is labeled as "oxygen sensor" on the ECU pin key

Pin #13 is shown as the brown wire connecting from the lambda sensor (Oxygen sensor), but is labeled "NTC" on the ECU pin key.

So none of this makes any sense.. are we supposed to believe the wire color codes and diagram path as correct and the ECU pin labels as wrong, or the ECU pin labels as right and the wire color codes and diagram path wrong?

nevermind that the engine temp sensor is labeled as dark green on the sensor side and green on the ECU side.. im just gonna assume the diagram path was drawn correctly! so many inconsistencies in the wiring diagram and the actual color codes of the wires in the harness!

wiringdiagram_-Stella_AUTOMATIC_125.jpg
full wiring diagram

sensor connections_-Stella_AUTOMATIC_125.jpg
the engine temp sensor is labeled as "NTC" here and shown as connecting to the dark green wire traced back to pin #3 on the ECU.

CDI pins_-Stella_AUTOMATIC_125.jpg
but once you look at the ECU pin labels, they list pin 3 as oxygen sensor, which would seem to mean the lambda sensor, not the CHT. so which is correct?

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Wed Mar 06, 2019 10:22 am quote
Contacted Genuine Scooters and got this response from their parts and warranties guy, Nathan:
Quote:
Hi Sean,

I suspect the wiring diagram that you found is an outdated version. Please consult this one, which has the correct wiring pinouts and color codes. Brown and black should be the engine temp sensor (polarity doesn’t matter though, and as you’ve already discovered, the new version of the temp sensor needs to be spliced in, as there is no one to one plug/socket option), and green/black should be the 02 (Lambda) sensor. Reading through your post on the forum, I have a feeling this one was ridden hard and put away wet its whole life. Chicago examples, which is also a winter salt-city, typically hold up better, but we are not dealing with salt water in the air from being near the ocean. New vacuum lines will be a good idea.



As for the carb, the air/fuel mixture should be set at 2.5 turns out for starters, and then fine tuned from there. You will know you have it set correctly when the idle is steady, and the air injection solenoid is cycling on and off periodically. Also, the initial startup will typically be a fast idle, and these bikes tend to “walk” about on their center stand, before coming down off the choke circuit. So a high idle at initial startup is normal, and then it should settle down from there.
So the sensor wiring from factory is correct.. which means the CHT warning light was correctly warning of a dead CHT sensor. Glad I replaced that, and didn't have to spend another $80-100 on a lambda sensor as well.

I'm still waiting on one small vacuum hose ordered online to replace the tube connecting to the air valve solenoid that drives the carb air mix. If i'm gonna replace some of the vacuum hoses with silicone, mine as well replace them all before I stick it back into the frame!

Stella_Automatic_125_Wiring_Diagram.jpg
Here is the updated correct diagram sent from Genuine Scooters

Stella_Automatic_125_Wiring_Diagram_sensorside.jpg
updated diagram with wire color and path to pins fixed...

Stella_Automatic_125_Wiring_Diagram_ecuside.jpg
traced back to correct pinout and sensor labels

Stella_Automatic_125_Wiring_Diagram.pdf
 Description:
Corrected and updated diagram from Genuine (printer friendly version)

Download
 Filename:  Stella_Automatic_125_Wiring_Diagram.pdf
 Filesize:  322.86 KB



Last edited by swiss1939 on Wed Mar 06, 2019 7:35 pm; edited 5 times in total
Addicted
GL, PK, PE200
Joined: 24 Apr 2012
Posts: 598
Location: Deep in the heart of Texas
Wed Mar 06, 2019 7:09 pm quote
Glad you did not take that old diagram as correct.

Nice project. I would not have had the patience and prob threw a 200cc motor in it. Being that the scooter was free and all plus there's prob very few 200cc lml autos on this side of the ocean... if any.

https://www.sip-scootershop.com/en/products/engine+lml+200cc+4stroke+_21000010

The insight you've provided is priceless. Keep up the good work and updates. I can't wait to see it complete.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Mar 07, 2019 10:14 am quote
rowdyc wrote:
The insight you've provided is priceless. Keep up the good work and updates. I can't wait to see it complete.
Thanks! last silicone hose im waiting on should be delivered today. Won't get a chance to finally get everything back together and into frame until Sunday at earliest. Hopefully everything goes well!
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Mar 07, 2019 2:38 pm quote
Got the vacuum hose I was waiting on earlier than expected today so I installed it and did some other small things while there.

IMG_20190307_155525.jpg
new vacuum hose I was waiting on, and the old one. attached to the air solenoid.

IMG_20190307_161720.jpg
air solenoid reinstalled with new hose.

IMG_20190307_162712.jpg
all the old cracked vacuum hoses removed.

IMG_20190307_161634.jpg
new vacuum hoses.

IMG_20190307_161646.jpg
new vacuum hoses.

IMG_20190307_161653.jpg
new vacuum hoses.

IMG_20190307_162454.jpg
new vacuum hoses.

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Mar 07, 2019 2:41 pm quote
I took the engine shock mount out to see if the rubber pad needs replacing. Probably not yet, but since its out and there is the beginnings of wear.. I'll change it.

IMG_20190307_164417.jpg
engine shock mount arm

IMG_20190307_164455.jpg
rubber pad on the shock mount arm, that sits inside frame and acts as a cushion.

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Mar 07, 2019 2:48 pm quote
Here is another mystery. I took the headset cover off because i'm gonna replace the inner and outer rear brake cable. When I took the cover off, I was checking the throttle cable to see if I should change that also, and some object fell into the opening of the right grip tube hole. So I took that right throttle grip arm off to get whatever fell in there out. Found this little plastic/metal object that looks like it may have broken off something inside the headset. I have no idea what it is or goes to.

Anyone know what this is? I would like to replace it if broken, or just re-install it correctly if not.

IMG_20190307_170831.jpg
the little plastic/metal piece fell into that tube opening and down to the end.

IMG_20190307_170442.jpg
so i took the throttle arm off and dropped that piece out of the tube.

IMG_20190307_170530.jpg
here is that piece that fell into the tube.

IMG_20190307_170537.jpg
back side of it.

IMG_20190307_170948.jpg
closer view of front.

IMG_20190307_170926.jpg
closer view of back.

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Mar 07, 2019 2:52 pm quote
RoaringTodd wrote:
I have no idea why LML went with this engine design, rather than sourcing a GY6 engine and modifying it to fit in the LML frame.

It was a great idea, since many people admired the Stella, and asked for it in twist and go. What sunk the 125 auto was the fact that it was only 125cc's (should have been at least 200), and that weird engine design which made it difficult to work on.

such a shame.
I think they did make a 200cc auto. But it was never imported to USA. I could be wrong.
Addicted
GL, PK, PE200
Joined: 24 Apr 2012
Posts: 598
Location: Deep in the heart of Texas
Thu Mar 07, 2019 7:38 pm quote
Try to get a parts diagrams from Scooter Works. Although parts are scares, you'll probably going to come up to other issues that a diagram could easily solve. AF1 Racing had one but it is no longer on their site.
Molto Verboso
1979 P150X, 1983 P200E, 1987 T5, 1996 PX200E, 2011 Yamaha Fazer 600 S2
Joined: 02 Aug 2015
Posts: 1472
Location: Veria, Greece
Thu Mar 07, 2019 10:30 pm quote
This plastic was part of the chrome end cap on the grip. It was there to hold the cap on the rubber. They break easily. Piaggio had similar grips on the PX Arcobaleno. The cap now is held by the glue they put along with the grip. It will probably fall at some point...

7ACA0467-7C9A-4906-A260-976196C84487.jpeg

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1980 P200E project, 2005 Stella Malossi 166 MKIII
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Thu Mar 07, 2019 11:27 pm quote
SaFiS wrote:
This plastic was part of the chrome end cap on the grip. It was there to hold the cap on the rubber. They break easily. Piaggio had similar grips on the PX Arcobaleno. The cap now is held by the glue they put along with the grip. It will probably fall at some point...
Thanks for the info! So it is on the inside of the grip as part of the chrome end cap? strange that it somehow worked its way up the tube and out that hole. cause it fell back in from outside when I took the headset cover off. Those chrome and plastic grips kinda feel cheap anyways. not a fan of them compared to the old style px grips. I actually prefer these rubber ones, despite being cheaper, they feel less cheap!
https://www.sip-scootershop.com/en/products/grips+for+vespa+125+gtrts150_17983600

my 2005 stella has these rubber grips.. not the original, as they are the piaggio label on them. Makes me wonder what kind were stock on the 2005 stella.
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1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Fri Mar 08, 2019 4:59 pm quote
Just realized I never posted images of the carb. The first thing I did when I picked this bike up was rebuild the carb as it was full of jello!

One question I still have is about how to re-install the throttle position sensor back correctly. the sensor slides over a spring loaded metal tab sticking out the side of the carb that is activated by the opening and closing of the throttle plate. The sensor itself has some spring loaded plastic piece that rotates on a center axis, with a slot for that metal tab to slide into which activates the rotation of that plastic sensor piece. I always reinstall the TPS back onto the metal tab by preloading the spring on the TPS plastic piece so that the two springs of the carb throttle plate and the TPS sensor act against each other. The screw hole in the TPS that mounts the TPS back onto the side of the carb has some horizontal range. I just reinstall it in the center of that range, so that the sensor is flush horizontal with the ground plane. I have been curious if there is a calibration process to reinstalling this throttle position sensor, seeing as in my mind it seems that should have some sort of accuracy, given that it defines the richness of the carb as all the sensors feed the ECU. I don't have specific images of this TPS mounting stuff cause I didn't think of it at the time. I'll try to get some of those next time I mess with it.

IMG_20181207_194934.jpg
I believe this is the automatic air fuel mixture inlet coming from the air solenoid tube that I replaced with blue silicone hose.

IMG_20181207_194038.jpg
carb waiting to be fully disconnected.

IMG_20181209_122638.jpg
carb removed.

IMG_20181207_200640.jpg
TPS sensor disconnected from wiring, which you can see there is some space on the plastic hole where the screw mounts, for adjustment. This is where I am wondering the correct alignment. inlet is for the fuel into float bowl. above that is the auto cho

IMG_20181207_200557.jpg
auto choke removed from the carb with the auto choke mount point and internals.

IMG_20181207_203713.jpg
auto choke mount point removed from the carb. above that is the metal tab from throttle plate that drives tps sensor.

IMG_20181207_203721.jpg
detail of the auto choke mount that shows the rubber gasket internal to it. This was in good shape, just needed varnish cleaned off it.

IMG_20181207_202314.jpg
that air inlet from the air solenoid again, with the throttle mechanism and cable mount on bottom right, spring loaded idle adjustment screw with long extension cable above that. bottom left is the spring loaded slide mechanism that is controlled by the

IMG_20181207_194634.jpg
float bowl and bleeder line/screw

IMG_20181207_212823.jpg
closeup of the spring loaded idle adjustment screw which attaches to the throttle mechanism.

IMG_20181207_204052.jpg
lid to the slide and needle section.

IMG_20181207_204114.jpg
slide spring.

IMG_20181207_204241.jpg
slide comes out with the needle attached.

IMG_20181207_205034.jpg
closeup of the needle parts that lock into center of the slide at the base of slide.

IMG_20181207_210210.jpg
float bowl lid off. This is where a ton of jello was causing issues.

IMG_20181207_210030.jpg
closeup of the lid with jello in it.

IMG_20181207_211710.jpg
jets mounted center of float.

IMG_20181207_212421.jpg
jet removed. I forget what size it is.

IMG_20181207_212538.jpg
all the various parts to the jets.

IMG_20181207_213820.jpg
float removed with float needle.



Last edited by swiss1939 on Fri Mar 08, 2019 5:05 pm; edited 1 time in total
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1980 P200E project, 2005 Stella Malossi 166 MKIII
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Fri Mar 08, 2019 5:02 pm quote
continued with carb rebuild.

IMG_20181207_214212.jpg
bowl lid has this spring loaded mechanism that is controlled by the tab on the throttle mechanism.

IMG_20181207_214414.jpg
detail of all the parts included in that section.

IMG_20181207_215052.jpg
air fuel mix needle with rubber gasket and spring

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1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Fri Mar 08, 2019 5:31 pm quote
Also figure I should post the manuals if anyone can't find them:

Parts Diagram:
https://drive.google.com/open?id=1hqIc71g5_--3cH0Bp-Rqeoao0eIFRNBP

Service Station Manual (wrong wiring diagram. correct one uploaded few posts above):
https://drive.google.com/open?id=1172_xErQmkRf010uWRORb2oeusLOMA-I
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Sun Mar 10, 2019 3:23 pm quote
The other day I tried to replace the rear brake cable inner and outer, using a front brake cable from the 2 stroke stella cable kit. Found out that the outer sheath from the front brake 2 stroke is not long enough. Did some searching online and found that the 125 auto stella had its own rear brake cable:
http://www.tassoparts.co.uk/cgi-bin/store.pl?action=link&sku=SF1530683&catafile=CATA_96&table=21&uid=930930&ref_id=

Tasso seems like is the only place with this exact part code from the parts diagram, and they are expensive including shipping, with long delivery. I tried to find it in local USA online shops to no avail. So I measured the original inner cable, coming in at somewhere around 1600-1800mm give or take what was already cut off the end. Did some researching on sip and other USA online shops to see if there was something similar in that size with same style sheath and cable ends, and the conclusion I came to is that the rear brake on the Stella 125 auto just uses the same cable as the 2 stroke stella clutch cable. On hindsight after spending an hour trying to find something similar on sip, I think it makes sense it would be the clutch cable since that is what that lever uses on the 2 stroke stella and I probably should have made that connection earlier. Unfortunately, that was the only cable I had actually used already out of the cable kit I had laying around. Snapped a clutch cable last fall.

https://www.sip-scootershop.com/en/products/cable+clutch+for+vespa+50125_94180150

So i've ordered this from scooter mercato and am waiting on it to swap out before I finally put everything back together on this bike and try to start it up.
Veni, Vidi, Posti
74 50s x2 78 P200 84 Cosa 58 AllState 68 Sprint 80 50special + projects
Joined: 22 Nov 2010
Posts: 6889
Location: seattle/athens
Mon Mar 11, 2019 9:58 pm quote
Good write up and even clear pictures. Google, if you're listening, this thread should be the goto destination for future Stella 125 Automatica queries...

Regardless, it's interesting seeing you discover the secrets of this rare bird. It sure makes me realize why I love my simple Vespas; I can easily understand most of the workings plus there's a worldwide internet full of most every part and experts for the things I need help with.

So thanks for sharing and here's an old tale by Joel Chandler Harris that your story somehow reminded me of :
https://youtu.be/riRMqNtl3ow (<-- Google Chrome ppl, click here)
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Wed Mar 13, 2019 7:03 pm quote
No picture update, BUT, good news! Finally had a day off with somewhat decent temperatures to spend the whole day trying to get this freekin thing back together and running. Got a clutch cable from Scooter Mercato, installed it as the brake cable for this bike. Outer sheath seems a bit long (probably cause the 2 stroke stella clutch cable crosses over frame from left to right instead of straight down the left side) so its kinda looped weirdly trying to fit in the available space right around the engine and into the rear brake cable adjustment arm. I had another clutch outer from the inner I used on my 2 stroke stella which I bought from Scooterworks last year. That one is 5-6" shorter so I may just take this one out and replace it with the scooterworks one which should fit fine.

Then spent a few hours carefully putting all the covers and parts back onto the engine (broke an LML 8mm bolt from tightening down, luckily have some replacements from USA which are stronger). I got the engine back into frame while routing all the wiring and reconnected everything. Put some fresh fuel in, reconnected battery, turned key and no more error codes! Pushed auto start, took 3 seconds first time and ran! Idled fine for a few minutes and turned it off. Then started it up and turned it off a few times and this thing starts immediately now and idles fine! So the problem was most likely valve clearances and possibly a little help from the vacuum hoses. I went overboard on this repair, definitely didn't need to take the engine out of frame to adjust the valve clearances, but I had to get that compression tester part out of the fan cover and wanted to replace the engine temp sensor (OCD in me couldn't handle seeing the warning light).

Tomorrow I gotta replace the front shock, a couple bulbs in the speedo and put the outer shell back together with the seat, etc. Then I'll take it for a ride to make sure it runs fine and idles once warmed up!

This one will get used while my 2005 stella gets a malossi 166 and the jetting worked out. Then I'll sell it!
Ossessionato
73 Rally, 74 Rally, 76 ET3, 80 P200, 63 Li125, 65 Li225 Silver Special, 86 Elite 80, 2015 HD Road Glide Special, 2011 Ural Tourist
Joined: 18 Jan 2012
Posts: 3187
Location: Oceanside/ SF
Wed Mar 13, 2019 7:10 pm quote
Great job! It sure was a project. You’ll have to let us know how they ride.

Your post and pics have me looking for a basket case one to mess around with. Nothing on the west coast at the moment.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Wed Mar 13, 2019 7:38 pm quote
MJRally wrote:
Great job! It sure was a project. You’ll have to let us know how they ride.

Your post and pics have me looking for a basket case one to mess around with. Nothing on the west coast at the moment.
Thanks! I look forward to your future basket case project thread!

Almost forgot, I need to replace the legshield trim which was chewed up and sticking out like a deadly weapon from when the original owner had it. I got the black plastic one from SIP. I'll replace that at some point in the future. No rush on that as I really want to sort out the jetting and install the malossi on my two stroke stella! Finally got a clear head to focus on my main stella once this thing will be free from major issues.
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Thu Mar 14, 2019 3:51 pm quote
Had some issues starting it today. Took some fiddling with the throttle adjustment screw to find the right point where it would start up every time. Also tried again with the service manuals suggestion for setting the idle speed at 15-1600 rpm. Every time I do that, it goes haywire and ramps up and down. It idles fine at 1250 so I'll leave it there.

Replaced the front shock and had to bend the front fender out a bit. Front fender was too narrow and getting caught on the old shock which was causing it to fold over into the springs and jam up. Measured the distance on my 05 stella front fender from outside edge to outside edge at 9.5 inches so I just pulled it apart until I hit the magic number. Then went in with a pair of pliers and bent out the folded over edge to try to smooth it out and keep it out of the way of the new shock.

Also noticed after replacing the shock that the front brakes are too tight and need to be spaced out. That wheel wont spin freely when brakes aren't pressed.

IMG_20190314_102518.jpg
Here is the fender issue.. after folding the curled edge back out. Smoothed it out some more after.

IMG_20190314_103802.jpg
bent back out of the way of the front shock.

IMG_20190314_102534.jpg
Here is the dead shock.

IMG_20190314_102551.jpg
some rusty studs

IMG_20190314_102641.jpg
paint flaking off this fork.

IMG_20190314_103946.jpg
old and new

IMG_20190314_102620.jpg
rusty nuts!

00100.jpg
new front shock installed.



Last edited by swiss1939 on Mon Mar 18, 2019 9:04 pm; edited 1 time in total
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Mon Mar 18, 2019 9:17 am quote
Scoot was still having difficulty starting... until i finally sat there and dialed in the air mix screw and throttle adjustment screw. Found some YouTube videos for similar gy6 scooters that showed how to make these adjustments. Got it started and warmed up, then turned throttle adjustment screw down till idle was at 850-900 lowest it would go before almost stalling. Then i turned air mix screw quarter turn each way observing which way increased idle and kept turning it toward the higher idle direction until turning it too far in that direction caused it to go back down (2 3/4 turns out). Then i was finally able to bring the throttle adjustment up until idle was at 1500 without the bike shaking on it's stand like an earthquake or the rear tire spinning like under full throttle. I then settled idle down at 1250 using the throttle adjustment screw. It now starts easier and idles proper. Before it was way too rich which made it hard to start and then idled out of control.

Warmed up idling after dialing carb:
https://photos.app.goo.gl/6S2gB5Ro18hXjqjP9

On to the next problem i noticed once i replaced the front shock... Front wheel won't rotate freely with no brake lever pressed. Front brake caliper is stuck closed. Took a while of wiggling to remove the caliper from the disc. Took pads out which were terrible shape, and can see the Pistons are rusted. Gonna have to rebuild the front brake caliper. On hindsight, this could have also been the burning smell when I took it for that only short 20 min ride. Front brakes grinding on the disc. Given it was tough to push the bike when off and loading into back of my truck when i first picked it up. Hopefully the front brake caliper is still serviceable and doesn't need to be fully replaced.

IMG_20190318_114039.jpg

IMG_20190318_114105.jpg

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Mon Mar 25, 2019 4:56 pm quote
Took the front brake caliper apart today and could not get the pistons out of the calipers. I've got them soaking in pb blaster to hopefully loosen them up. Using the air compressor which only goes up to 125 psi to hit it with bursts of air could not get them to pop out.

I guess if I can't get them out, I'll have to replace the front brakes with the one on my 2T stella, and put some new SIP ones on that bike.

IMG_20190325_144849.jpg

IMG_20190325_144853.jpg

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Wed Apr 17, 2019 3:28 pm quote
Blew a fuse in my garage a couple weeks ago on the last particularly cold night here in NYC, cause I was using 4 large fluorescent lights and a space heater to see and not freeze and a heat gun at night to try to get the brake pistons that were seized out of the front caliper for this bike. Maintenance guy never got back to me and today was the first day I was able to get there during the day so I could finish the job with a blowtorch!

Finally got those damn brake pistons out of the caliper. Gonna clean everything up and install new seals and finally be done with this damn stella automatic. Can't wait to sell it and get some more room in my garage for new projects!

IMG_20190417_191711.jpg
finally got everything apart

IMG_20190417_191732.jpg
these made me angry

IMG_20190417_191753.jpg
they look good so i'm hoping a good cleaning and everything is reusable

IMG_20190417_190309.jpg
unrelated, but my garage neighbor pulled this out while I was there. Love the cheesy 80s style.

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Wed Apr 17, 2019 9:08 pm quote
A while in the ultrasonic cleaner still couldn't get some of the crud on the caliper stuck in the holes for the pistons out. So next chance I get, I'll try a while in the ultrasonic cleaner again and use a brass brush to try to clean that crap out. then polish the pistons and put everything back together!
Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Sat Apr 20, 2019 8:15 pm quote
Oh boy! Finally had a full day off with great weather and electricity in my garage. Spent the whole day in there finishing this damn stella automatic, broken up by a nice long ride on my 2T stella every couple of hours.

Left my garage at 11pm with literally everything fixed and the whole bike back together ready to ride!

I rebuilt the brake caliper this morning, then replaced the speedo cable, then tore off the mangled chrome leg shield trim and spent 2 hrs putting the black plastic replacement trim on it. No leg shield trim tool, just bear hands and brute force.

Here is the list of everything I have done since picking this non-running scooter up in early December, with very sporadic and short bursts working on it since I have been extremely busy with work since December. Bear in mind, a majority of this stuff is the first time i've ever done any of this, aside from oil and cable changes on my 2T stella. Never touched a 4 stroke engine or an automatic scooter before this one.

Replaced
New Battery
Engine Temperature Sensor
All Vacuum lines
All Fuel Filters
Air Filter
Oil Filter
Glove Box Lock
Glove Box Latch mechanism
Ignition Lock
Lock Body
Lock Body Rubber
All electrical rubber covers
random speedometer lightbulbs
Speedometer Cable
Rear Brake Cable
Front Brake Pads
Spark Plug
HT Coil
Front Shock
Leg Shield Trim


Other Repairs Performed
Valve Clearance Adjustment
Front Brake Caliper Rebuild
Carb Clean/Rebuild
Gear and Engine Oil changes


Out of all this stuff, the hardest thing to do was the damn leg shield trim, no joke! Left the headset and handlebars on, but had to take the glove box and turn signals off to do it. Lots of swearing and sweating and two hours later, new trim on! Also getting the brake pistons out was quite a pain, but once I used a blow torch to heat the calipers up, they came out quick.

I'm gonna finally take it out for a test ride tomorrow and maybe work on the front brake a bit cause the lever is still a bit squishy after completely draining the fluid when I pulled the caliper off to rebuild. I'll post a video of it running tomorrow.

IMG_20190420_155052.jpg
Mangled leg shield trim

IMG_20190420_155110.jpg
old chrome trim. not a fan of chrome.

IMG_20190420_195137.jpg
new black trim.

IMG_20190420_195144.jpg

IMG_20190420_204617.jpg
I was thinking of putting black trim on my 2T, but it was such a pain in the A, I'll wait till I repaint it to do that.

Addicted
1980 P200E project, 2005 Stella Malossi 166 MKIII
Joined: 20 Jul 2018
Posts: 747
Location: Staten Island, NY
Sun Apr 21, 2019 11:31 am quote
Went for test ride today for half an hour or so. Runs fine with max speed 51 mph. Slower than my 2 stroke but with better torque. It feels like all thumbs with awkward handling compared to my 2 stroke stella. I'll stick to the shifty.

This is how it ran when I first picked it up in Dec 2018:
https://drive.google.com/open?id=1Wm73P-h7YMWBm3Vh0yZVu147iXfrkC-_

This is how it runs today after spending a few days over the past couple months fixing everything:
https://drive.google.com/open?id=1H2EqUvin1vBUeSymEs8oSV6rR9peCMuM

This thing is going up on craigslist now that it's finally done. Need space in my garage for an old vespa!

Finished look:


IMG_20181130_215102_01.jpg
How it looked when I first picked it up

IMG_20181130_220049_01.jpg
mangled leg shield trim before repairs.

IMG_20181130_220108_01.jpg
mangled ignition lock and lock body when I first picked it up.

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GL, PK, PE200
Joined: 24 Apr 2012
Posts: 598
Location: Deep in the heart of Texas
Fri Apr 26, 2019 12:29 pm quote
GREAT JOB! I'm glad you saved it. Someone will enjoy the crap out of it.
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