Sun Jul 10, 2022 9:26 am

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 9:26 am linkquote
Hey all,

Here I am in the US with a German-market P80X. The original cylinder and head were roasted, so of course, upgrades were in order. And order I did, many many moons ago. Only this winter did I finish assembly. Now that it's tuning/jetting time, I think I made parts mistakes. Let me just lay it all out.

Changed out clutch and primary gear to give myself some legs with a larger cylinder. That Malossi kit.

Grabbed the DR 177cc kit from SIP that's milled to fit the smaller case opening of my P80X. Kept the stock exhaust, thinking I could upgrade later. And having read (perhaps erroneously) that a SI 24/24 would do me good, bought a 24/24g carb meant for a T5. Modified a standard 24/24 air filter to fit the g.

I made poor choices, and on a run this past Friday, soft seized the engine. I got too bold! So obviously my jetting is not right. Here's what I'm running as far as jets go:

Atomizer: BE4
Main Jet: 115
Air Jet: 120
Idle Jet: 50/100
Air mix screw out 2-1/2 turns

I know about pulling plugs (thought I was close enough so didn't check), but would like to know if I'm even in the right ballpark before I even try taking it back on the road for testing.

So questions: am I better off totally rejetting my crusty OG 20/20 carb to work with this setup of DR177+stock exhaust or working to dial in the 24/24g? Google results seem inconclusive as to what I should do.

Thank you!

Scooter Tax:
[img] https://members.modernvespa.net/meltshow/uploads/2a8b4c84_afdb_4f6c_a16b_9a145134e672_74524.jpeg[/img]


Scooter tax

Sun Jul 10, 2022 9:35 am

Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
 
Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
Sun Jul 10, 2022 9:35 am linkquote
Starting from the basics

Are you familiar with running in procedure of 2T engine?
Did you check the ring gap when installing the cylinder?
How long has the engine been driven with the fresh top end?
Sun Jul 10, 2022 9:52 am

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
Sun Jul 10, 2022 9:52 am linkquote
FINYoshi wrote:
Starting from the basics

Are you familiar with running in procedure of 2T engine?
Did you check the ring gap when installing the cylinder?
How long has the engine been driven with the fresh top end?
cylinder head temperature gauge to know how hot your getting.

Did you pressure test motor to check for air leaks?
Sun Jul 10, 2022 9:56 am

Ossessionato
1979 P150X, 1983 P200E, 1988 T5, 1995 PX200E, 2011 Yamaha Fazer 600 S2
Joined: 02 Aug 2015
Posts: 3204
Location: Veria, Greece
 
Ossessionato
1979 P150X, 1983 P200E, 1988 T5, 1995 PX200E, 2011 Yamaha Fazer 600 S2
Joined: 02 Aug 2015
Posts: 3204
Location: Veria, Greece
Sun Jul 10, 2022 9:56 am linkquote
Stock exhaust on a kitted engine is a huge restriction resulting in overheating...
Sun Jul 10, 2022 9:58 am

Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
 
Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
Sun Jul 10, 2022 9:58 am linkquote
SaFiS wrote:
Stock exhaust on a kitted engine is a huge restriction resulting in overheating...
I disagree. If set up properly, even a stock exhaust will work just fine.
Sun Jul 10, 2022 10:21 am

Addicted
Joined: 28 May 2020
Posts: 570
Location: Planet Earth
 
Addicted
Joined: 28 May 2020
Posts: 570
Location: Planet Earth
Sun Jul 10, 2022 10:21 am linkquote
I run a dr177 with road 2.0 , modded filter 24mm si, matched carb inlet box, sip 2 fast flow tap, and use ac140 Be5 121 main and 50/120 pilot. I run on 7 grade heat plug B7HS and change to 8 grade for long runs. That's bang on and arrived at by the lads on this forum. As you got standard pipe I'd knock off 3 to 4 on main I've specified so 118 ish. So this is what you're looking at and pretty typical with others I know who have same setup.
Sun Jul 10, 2022 11:58 am

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 11:58 am linkquote
FINYoshi wrote:
Starting from the basics

Are you familiar with running in procedure of 2T engine?
Did you check the ring gap when installing the cylinder?
How long has the engine been driven with the fresh top end?
1) Not really. All of my experience has been with 4T engines. And with them, it's usually either "ride it hard!" or "take it slow" depending on who you ask.

2) Ring gap. Brand new ring+cylinder kit. Would I need to check ring gap?

3) No more than two hours at low speeds, and not terribly far until this most recent ride to let it stretch its legs.
Sun Jul 10, 2022 11:59 am

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 11:59 am linkquote
Christopher_55934 wrote:
cylinder head temperature gauge to know how hot your getting.

Did you pressure test motor to check for air leaks?
Is there a CHT kit everyone recommends? I've seen the Trailtech name tossed around but am not sure which probe works for us.

Pressure test: not before the seize. Just ran a pressure test now in the garage and only saw ~100 psi. Not good!
Sun Jul 10, 2022 12:01 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 12:01 pm linkquote
ferriswolf wrote:
I run a dr177 with road 2.0 , modded filter 24mm si, matched carb inlet box, sip 2 fast flow tap, and use ac140 Be5 121 main and 50/120 pilot. I run on 7 grade heat plug B7HS and change to 8 grade for long runs. That's bang on and arrived at by the lads on this forum. As you got standard pipe I'd knock off 3 to 4 on main I've specified so 118 ish. So this is what you're looking at and pretty typical with others I know who have same setup.
Can I run the same jets in my 24/24g? I'd have to modify the heights of some jets to fit, I think.

Also, thank you all for hopping on with things to check/learn. Much appreciated!
Sun Jul 10, 2022 12:06 pm

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
Sun Jul 10, 2022 12:06 pm linkquote
meltshow wrote:
Is there a CHT kit everyone recommends? I've seen the Trailtech name tossed around but am not sure which probe works for us.

Pressure test: not before the seize. Just ran a pressure test now in the garage and only saw ~100 psi. Not good!
I meant a different type of test, a 2T motor can suck in air that isn't metered and mixed with fuel and oil on it's way into the cylinder to get burnt.

Sun Jul 10, 2022 12:12 pm

Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
 
Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
Sun Jul 10, 2022 12:12 pm linkquote
The DR isna cast iron cylinder which is quite sensitive to running in. Should be ridden only short runs of just couple miles at first and then gradually lenghtened. Stable load is not so good in the beginning. Running in should be done on varying loads to let the cylinder accumulate some heat and then taken more slow to let it cool down.

Ring gap should always be checked when installing a piston. Most times it is fine out of the box but not always. Too tight gap will cause seizing.

Few hours means the most sensitive part of running in is already over. What was the situation when the engine seized? Speed, uphill, downhill, accelerating, stable speed etc?
Sun Jul 10, 2022 12:18 pm

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
Sun Jul 10, 2022 12:18 pm linkquote
meltshow wrote:
Is there a CHT kit everyone recommends? I've seen the Trailtech name tossed around but am not sure which probe works for us.

Pressure test: not before the seize. Just ran a pressure test now in the garage and only saw ~100 psi. Not good!
Does your scooter have a battery? If it has a supply for 12 VDC I prefer meters by Koso, you can replace just the ring that goes under the spark plug.

https://kosonorthamerica.com/product/cylinder-head-temperature-sensor-with-black-connector-0-250c-%E2%88%BC-32-482f/
Sun Jul 10, 2022 1:49 pm

Jet Eye Master
PX221 MHR, O tuned PX200, PX181 Quattrini and some motorbikes
Joined: 14 Jun 2017
Posts: 3444
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX181 Quattrini and some motorbikes
Joined: 14 Jun 2017
Posts: 3444
Location: London UK
Sun Jul 10, 2022 1:49 pm linkquote
meltshow wrote:
1) Not really. All of my experience has been with 4T engines.
4 Stroke engines are simple. One part, one job. 2 Strokes are similar to Jazz music. Shouldn't work but actually amazing.

You probably peaked too soon. Bigger main jet. Get it running. Wear all the bruises off. Will be fine.
Sun Jul 10, 2022 2:43 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 2:43 pm linkquote
FINYoshi wrote:
Ring gap should always be checked when installing a piston. Most times it is fine out of the box but not always. Too tight gap will cause seizing.
I'll probably remove the head tonight to inspect the cylinder and will check this.
FINYoshi wrote:
Few hours means the most sensitive part of running in is already over. What was the situation when the engine seized? Speed, uphill, downhill, accelerating, stable speed etc?
I was just cresting a long low hill, somewhere between 3/4 and WOT. Having that rear wheel lock up is VERY THRILLING and an experience I do not wish to repeat. Fortunately, my reflex was to pull the clutch and I straightened it out.

I coasted to a stop and let the scoot cool off for 5-10 minutes (as well as my heart rate). It didn't want to fire up with the kickstart so eventually I rolled it into 1st gear and it purred back to life. Rode the whole 2-3 miles home at 1/4 throttle at about 25mph for fear of what I'd done.
Sun Jul 10, 2022 2:47 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 2:47 pm linkquote
Jack221 wrote:
4 Stroke engines are simple. One part, one job. 2 Strokes are similar to Jazz music. Shouldn't work but actually amazing.
I'm still wrapping my head around how it managed to work.
Jack221 wrote:
You probably peaked too soon. Bigger main jet. Get it running. Wear all the bruises off. Will be fine.
I've got a whole main jet kit on the way.

How important is the air mixture screw to more open throttle?

The original 24/24G mixture screw has a very large tip (~1.5mm Ø) and the replacement in there now is that standard 24/24 thin-tip. I'm probably suuuuuper lean with just that. It doesn't fill the hole in the carb throat even when entirely screwed in. I have the idle screwed all the way in to compensate. (This is where you go 'you fool!')
Sun Jul 10, 2022 4:01 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 4:01 pm linkquote
ferriswolf wrote:
I run a dr177 with road 2.0 , modded filter 24mm si, matched carb inlet box, sip 2 fast flow tap, and use ac140 Be5 121 main and 50/120 pilot. I run on 7 grade heat plug B7HS and change to 8 grade for long runs. That's bang on and arrived at by the lads on this forum. As you got standard pipe I'd knock off 3 to 4 on main I've specified so 118 ish. So this is what you're looking at and pretty typical with others I know who have same setup.
All of these things are on their way to me (maybe SIP 2.0 some day). I'll need to shorten the 50/120 pilot/idle to fit my carb, but all else is easy peasy. Thanks for the first-hand help!
Sun Jul 10, 2022 8:09 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sun Jul 10, 2022 8:09 pm linkquote
So I've never heard a 2T Vespa running in person so I have no point of reference. Besides the wandering idle (how important is it that the airbox is airtight?), is this amount of chatter normal? I've read that the DR kit can be pretty noisy.

Video:
https://youtu.be/_ugV2jufs5M[/url]
Sun Jul 10, 2022 10:10 pm

Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1862
Location: UK (South East)
 
Molto Verboso
One or two fun scoots....nothing too precious
Joined: 17 Jul 2013
Posts: 1862
Location: UK (South East)
Sun Jul 10, 2022 10:10 pm linkquote
The 24/24g and the stock P80X exhaust is an unusual combination IMO. Had you bought a 24/24e, the jetting put forward by Ferris is about right (with a decent exhaust). My own DR177 (with 24/24e and BGM Touring exhaust) is very close to Ferris, although my main is 125 on account of a venturi in place of the air filter. The T5 had a very good and sporty pipe, so I'm with SaFiS on this one. You need to get a suitable exhaust as your baseline. That said, your motor has totally different characteristics to a T5. As far as the main jet is concerned, the T5 uses a 110 in stock form and [generally] a 122 or 125 with the Malossi 172 kit. With yours being a low tune DR177, I don't think your 115 MJ is that far off, but I'd think ~118 with a decent exhaust. With the 120 air corrector, the main is always going to be smaller than with a 140 or 160 AC.

Did you open and blend the inlet? If not, a 20/20 would be a tried and tested carb and easy to jet, based on many other examples out there.
Sun Jul 10, 2022 11:15 pm

Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
 
Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
Sun Jul 10, 2022 11:15 pm linkquote
meltshow wrote:
I was just cresting a long low hill, somewhere between 3/4 and WOT.
Long pull on high(ish) power demand with a fresh top end is a recipe for soft seize. No biggie and will be fine.

When you take the cylinder and head off, use can use some fine 400-600 grit sanding paper in criss-cross pattern to get rid of the marks on the cylinder and piston. Not absolutely necessary but will make the life of piston a tad easier.

One speciality about running in 2T engines is the used oil. Avoid top shelf 2T oils during running in, since they will slow wearing in the parts. Using some cheap mineral 2T oil makes the progress faster but you also have to take it gently with no long high power pulls. Low varying load is the way to go.
Mon Jul 11, 2022 12:05 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Mon Jul 11, 2022 12:05 pm linkquote
swa45 wrote:
The 24/24g and the stock P80X exhaust is an unusual combination IMO. You need to get a suitable exhaust as your baseline.
I appreciate the advice! Looks like a SIP Road exhaust is what I'll use for my baseline.
swa45 wrote:
Did you open and blend the inlet? If not, a 20/20 would be a tried and tested carb and easy to jet, based on many other examples out there.
Yes! This at least I knew to do. Thanks.
Mon Jul 11, 2022 12:59 pm

Addicted
Joined: 28 May 2020
Posts: 570
Location: Planet Earth
 
Addicted
Joined: 28 May 2020
Posts: 570
Location: Planet Earth
Mon Jul 11, 2022 12:59 pm linkquote
swa45 wrote:
The 24/24g and the stock P80X exhaust is an unusual combination IMO. Had you bought a 24/24e, the jetting put forward by Ferris is about right (with a decent exhaust). My own DR177 (with 24/24e and BGM Touring exhaust) is very close to Ferris, although my main is 125 on account of a venturi in place of the air filter. The T5 had a very good and sporty pipe, so I'm with SaFiS on this one. You need to get a suitable exhaust as your baseline. That said, your motor has totally different characteristics to a T5. As far as the main jet is concerned, the T5 uses a 110 in stock form and [generally] a 122 or 125 with the Malossi 172 kit. With yours being a low tune DR177, I don't think your 115 MJ is that far off, but I'd think ~118 with a decent exhaust. With the 120 air corrector, the main is always going to be smaller than with a 140 or 160 AC.

Did you open and blend the inlet? If not, a 20/20 would be a tried and tested carb and easy to jet, based on many other examples out there.
The man is right , you don't need the 24mm and for simplicity go back to the 20mm. A dr177 and road 2 will hit its max power on 3 quarter throttle so the 20mm WOT will emulate the same. if you were doing a gear up via the clutch cog then maybe a 24mm would help but I'm hitting 65 mph gps without clutch cog change and characteristics of my driving the current gearing is more balanced for me. The 20mm , loads of folks in here have used with dr 177 and likely can get you in the bullpark jetting if not spot on. The dr177 should be driven 400k at no more than 45 mph running in , it's a slog putting those miles in at low speed but the kit will be very reliable if you follow the DRs running in guidelines.
Mon Jul 11, 2022 1:30 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Mon Jul 11, 2022 1:30 pm linkquote
ferriswolf wrote:
The man is right , you don't need the 24mm and for simplicity go back to the 20mm. A dr177 and road 2 will hit its max power on 3 quarter throttle so the 20mm WOT will emulate the same. if you were doing a gear up via the clutch cog then maybe a 24mm would help but I'm hitting 65 mph gps without clutch cog change and characteristics of my driving the current gearing is more balanced for me. The 20mm , loads of folks in here have used with dr 177 and likely can get you in the bullpark jetting if not spot on. The dr177 should be driven 400k at no more than 45 mph running in , it's a slog putting those miles in at low speed but the kit will be very reliable if you follow the DRs running in guidelines.
Good to know, thanks!

Fun P80X facts: Since they were originally intended for new riders (teens) in Germany, they were limited in more ways than just the cylinder size and carb jetting. They have a shorter crankshaft (48mm stroke) and different primary gear (20/68) and much shorter gears. So you can't just toss a massive jug on there and party, is how I understand it.

Long story short: I have swapped the clutch & primary gear (23/64) to give me more legs, along with crank, cylinder, etc.
Tue Jul 12, 2022 12:26 am

Jet Eye Master
PX221 MHR, O tuned PX200, PX181 Quattrini and some motorbikes
Joined: 14 Jun 2017
Posts: 3444
Location: London UK
 
Jet Eye Master
PX221 MHR, O tuned PX200, PX181 Quattrini and some motorbikes
Joined: 14 Jun 2017
Posts: 3444
Location: London UK
Tue Jul 12, 2022 12:26 am linkquote
meltshow wrote:
I'm still wrapping my head around how it managed to work.

I've got a whole main jet kit on the way.

How important is the air mixture screw to more open throttle?

The original 24/24G mixture screw has a very large tip (~1.5mm Ø) and the replacement in there now is that standard 24/24 thin-tip. I'm probably suuuuuper lean with just that. It doesn't fill the hole in the carb throat even when entirely screwed in. I have the idle screwed all the way in to compensate. (This is where you go 'you fool!')
Pictures would be a big help. Have seen old style mix screws forced into the wrong thread before. Same thread and same screw type would be close enough. Any major difference is probably not good. However, once the throttle slide is about 2mm open the mixture screw goes off line and the pilot jet feeds directly.
As so much time is spent at near closed throttle, it's really important to get it right.
Wed Jul 13, 2022 8:42 am

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Wed Jul 13, 2022 8:42 am linkquote
Jack221 wrote:
Pictures would be a big help. Have seen old style mix screws forced into the wrong thread before. Same thread and same screw type would be close enough. Any major difference is probably not good. However, once the throttle slide is about 2mm open the mixture screw goes off line and the pilot jet feeds directly.
As so much time is spent at near closed throttle, it's really important to get it right.
Gladly! On the left is the large-tipped air mixture screw from the 24/24g, on the right is the corresponding screw from your standard 24/24e. You'll notice that the g needle is...wonky. It broke off and I did a bodge job soldering it back on. I have two of the 24/24e screws but I'm worried that it'll lean me out too far to use. Hard to rationalize $40 of shipping from Germany for a ~$8 screw from SIP if I can make something else work.


24/24g mixture screw vs 24/24e

Wed Jul 13, 2022 8:52 am

Addicted
Joined: 28 May 2020
Posts: 570
Location: Planet Earth
 
Addicted
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Posts: 570
Location: Planet Earth
Wed Jul 13, 2022 8:52 am linkquote
meltshow wrote:
Good to know, thanks!

Fun P80X facts: Since they were originally intended for new riders (teens) in Germany, they were limited in more ways than just the cylinder size and carb jetting. They have a shorter crankshaft (48mm stroke) and different primary gear (20/68) and much shorter gears. So you can't just toss a massive jug on there and party, is how I understand it.

Long story short: I have swapped the clutch & primary gear (23/64) to give me more legs, along with crank, cylinder, etc.
It's strange these euro laws. The same can be said of Spanish law and the age of drivers not being able to have anything above 75cc hence the pk 75 and all the other weird German/Belgian euro pk primavera 75cc, looked nothing like a pk, but like a primavera with a 50 special square headset and storage box on left side panel. I love the quirkiness but bastard pain in arse to kit. Mine has a 43mm crank but 125 cylinder studs and 3 stud ETS inlet and carb ; mad.one should probably avoid buying these Frankenstein scoots in the first place but like the last ugly runt puppy left in the litter you just got to have it out of curiosity.
Wed Jul 13, 2022 8:54 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Wed Jul 13, 2022 8:54 pm linkquote
So let me introduce this scoot of mine. I know it's not a freaking awesome pre-P-series bike but it's what I got. So it was a Craigslist find for $400 back when we lived in Phoenix, Arizona. A small tree was attempting to grow through the front fork, all the rubber was shot, the wiring harness was roasted, and so on. I really could go on (mouse nest in the airbox!). It looked fab from 6 paces away.

As the story goes, a member of the US Armed Forces managed to bring it back home from Germany but I don't believe it was ever registered here in the states.

In hindsight, I wish I had invested more time in getting it running back when I first got it, but hey, I've still had a LOT OF FUN working through it recently. All good!


The night I brought the P80X home. Parked in front of my '77 Honda CB550F.


No keys to be had and that headset is mostly cardboard and body filler.


German-ness intensifies. I recreated this sticker.


I couldn't quite afford to dig into it at the time (2016), so it followed me through a couple of moves.

Thu Jul 21, 2022 9:52 am

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Thu Jul 21, 2022 9:52 am linkquote
My original plan for the P80X was to strip it down and paint it in minty green as quickly as possible, so I could enjoy all 80ccs of glory. I got as far as tearing it all down and paint + rust removal before life happened, though! Before I short of shrink-wrapped the whole assembly, I was able to make a few quick fixes.

The frame was actually in pretty good shape: mostly surface rust with the worst pitting down near the frame rails. It was dropped at some point on the right side but nothing I couldn't coerce back into shape. The RH cowl was pretty thrashed!

The steering stop on the left-hand side was also rounded out, which a chisel and bit of welded-on material solved nicely.

That's where things were at in late 2017, when a good period of unemployment and a move across state lines stopped the build.


Headset cover was cardboard, filler, and dreams. The headlight didn't have a lens.


Very dusty in here. Not bad, considering a small tree was attempting to grow its way through here.


The fuel tank had a run-in with material fatigue in the past, in more ways than you can see here.


Stator wiring was cooked, which I now understand is pretty common.


Complimentary earwax in the gear selector box.


Paint all over was rather toasty.


Surface rust all over here.


How it sat until January 2022.

Thu Jul 21, 2022 5:46 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Thu Jul 21, 2022 5:46 pm linkquote
I got a new T5 air mixture screw from vespajets over in the UK and gave it the ol' grindy grind so it will clear the OG p-series airbox. I also added a groove for a flat-head screwdriver for adjustments. Finally, the airbox rubber plug can fit into its place over the air mix screw.

Also, fun things are the SIP Road exhaust I installed and a larger main (#122). All of a sudden it's one-kick starting. Just like you guys said: it's what the bike needed. Took it out for a jaunt this morning, and neither I nor the bike died. Thumbs up all around.

I live in this very particular area of east of the San Francisco Bay with practically never-ending wind. Most trees end up growing at a diagonal angle. We've averaged 16mph for the month of July, and this morning I definitely felt it on the scooter. It felt like I was getting tossed all around!

I'll have to get used to it.


Shortened T5 air mix screw


P80*X this morning


My neck of the woods near Suisun Marsh.

Fri Jul 22, 2022 6:44 pm

Hooked
'58 VBA '79CT90
Joined: 25 Dec 2019
Posts: 141
Location: Chico CA
 
Hooked
'58 VBA '79CT90
Joined: 25 Dec 2019
Posts: 141
Location: Chico CA
Fri Jul 22, 2022 6:44 pm linkquote
Cleaned up real nice. Good job. Love the color.
Sat Jul 23, 2022 12:19 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sat Jul 23, 2022 12:19 pm linkquote
Grumpnut wrote:
Cleaned up real nice. Good job. Love the color.
Thanks! Prep and painting took SO MUCH SANDING. Hours of life. I get why having it done can be so pricey. Lots of man-hours there, and even then for me the results are (in my opinion) only good enough.








This is probably the body between color and clear coats.

Sat Jul 23, 2022 12:39 pm

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
Sat Jul 23, 2022 12:39 pm linkquote
meltshow wrote:
Thanks! Prep and painting took SO MUCH SANDING. Hours of life. I get why having it done can be so pricey. Lots of man-hours there, and even then for me the results are (in my opinion) only good enough.
Yeah, if I ever want a great paint job, I'm going to strip scooter of everything, clean it up and get it painted professionally.
Sat Jul 23, 2022 12:40 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Sat Jul 23, 2022 12:40 pm linkquote
So I took your advice to heart and ran the original SI 20/20d and it's bits through the sonic cleaner a few times. It cleaned up super nicely (no more tiny mouse turds) and I've got it jetted out thusly:

Atomizer: BE3
Main Jet: 115
Air Jet: 160
Idle Jet: 50/120
That jet under the float cover (slow run?): 60
Air mix screw out 1-1/2 turns

And it runs! Very well in fact. Gave it the 'ol round the neighborhood to the gas station for a fill-up.


SI 20/20d from the P80X

Mon Jul 25, 2022 10:40 am

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Mon Jul 25, 2022 10:40 am linkquote
Dropped down to a 140 AC and now I'm seeing temps under 300F. With air screw set stock (1.5 turns) the scooter idles pretty rich. Kind of bogs? A leaner idle jet could help with that, right? I'm thinking I could work upwards until it idles happily. I've got a 52/140 handy, which is a notch or two in that direction.

Returned from a quick ride Sunday afternoon to see my headlight lens peeling right off. This was a new replacement from SIP. Not the best adhesive, I guess! A little acetone to clean it off and it was back on with fresh silicone holding the lens on.


It's like the adhesive gave up.

Mon Jul 25, 2022 1:01 pm

Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
 
Hooked
Parmakit Primavera -74, Polini Primavera -68, Stock 150 Touring -59, VMC 177 Bajaj Chetak 125 -95
Joined: 22 Jun 2022
Posts: 397
Location: Finland
Mon Jul 25, 2022 1:01 pm linkquote
Shouldn't that have a metal ring around it to keep the reflector and glass together?
Mon Jul 25, 2022 3:41 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Mon Jul 25, 2022 3:41 pm linkquote
FINYoshi wrote:
Shouldn't that have a metal ring around it to keep the reflector and glass together?
Hei! Your guess is as good as mine: I'm not sure these had a metal ring from the factory. I don't see one in the P80X pics I've pulled up from Google.
Mon Jul 25, 2022 3:46 pm

Style Maven
'74 50s x3 '78 P200 E '84 Cosa '91 PK50XL2 '58 AllState '68 Sprint '80 50special and a '66(?) Super125
Joined: 22 Nov 2010
Posts: 8793
Location: seattle/athens
 
Style Maven
'74 50s x3 '78 P200 E '84 Cosa '91 PK50XL2 '58 AllState '68 Sprint '80 50special and a '66(?) Super125
Joined: 22 Nov 2010
Posts: 8793
Location: seattle/athens
Mon Jul 25, 2022 3:46 pm linkquote
meltshow wrote:
...

Returned from a quick ride Sunday afternoon to see my headlight lens peeling right off. This was a new replacement from SIP. Not the best adhesive, I guess! A little acetone to clean it off and it was back on with fresh silicone holding the lens on.
Don't use silicon, try clear Shoe Goo. Strong as hell, but removable without a trace if you need to. It's like rubber glue on steroids.
Mon Jul 25, 2022 3:53 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Mon Jul 25, 2022 3:53 pm linkquote
V oodoo wrote:
Don't use silicon, try clear Shoe Goo. Strong as hell, but removable without a trace if you need to. It's like rubber glue on steroids.
I have a huge unopened tube of Shoe Goo. Didn't even think of it. Thanks!
Mon Jul 25, 2022 5:38 pm

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
Mon Jul 25, 2022 5:38 pm linkquote
FINYoshi wrote:
Shouldn't that have a metal ring around it to keep the reflector and glass together?
No, glued on newer models.
Tue Jul 26, 2022 4:51 am

Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
 
Ossessionato
2007 Stella 225
Joined: 02 Nov 2019
Posts: 3052
Location: Rochester, Minnesota
Tue Jul 26, 2022 4:51 am linkquote
V oodoo wrote:
Don't use silicon, try clear Shoe Goo. Strong as hell, but removable without a trace if you need to. It's like rubber glue on steroids.
I used to race foam tire rd cars circle track. We used shoe goo to repair foam tires that got cut and chunk was still there.
Tue Jul 26, 2022 1:04 pm

Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
 
Member
1981 P80X
Joined: 18 Feb 2016
Posts: 47
Location: Fairfield, CA
Tue Jul 26, 2022 1:04 pm linkquote
Okay, so scenario time. I was pulling into a stop after running the engine up to the 300F range in 4th gear (around 1/2 throttle), downshifted to 3rd, and kept the revs up. Seemed happy until I pulled the clutch into the turn, and the engine died. Not the end of the world. It wouldn't start back up again, so I schlepped it the 1/2 mile to the house. Maybe an hour later, I was able to get to it. Still no start.

Pulled the plug, which was a nice light-to-medium brown. However, that dang CHT 14mm sensor (trail tech) was coated on both sides with a lovely black oily residue. Same with the plug where the two meet, and peering at the cylinder head opening, the same is true. Wiped that crap off, threaded it back in, gave it a kick, and bam, happy one-kick starting again.

In your opinions, did my plug finally leak enough in that final stretch of road to cause it to die? Much appreciated!
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