Modern Vespa

108: Timings are at the top of the second page...

jack: The SI came with the slide with the two extra "air" pockets (right one in the photo). First time I see it on a "PX" SI. Looks like the one I have on my T5. Bought two extra slides (middle and left in photo), one like the normal all the 200s use and one with a smaller cutaway. Also, what about jetting?? Where should I start?? I have the following...

AC
120
140
160

Mixer Tubes
BE3
BE4

Idle Jets
50/120
50/140
50/160
52/120
52/140
55/100
55/160

Main Jets (nothing below 140, but I'll get some from my supplier on Friday)
140
142
145
148
150
152
155
158
160
162

Here's where I would start with that pile of bits.
Use the 04 slide with the top pockets.
Drill the float bowl to 2.5mm
Vortex instead of air filter
AC120 never use any bigger but might need smaller
BE4 nothing weaker
55/100 fixed also
Main jet 140 to start but wil go smaller

New tunnel tray, got an extra ground wire from the engine directly onto the regulator, two extra drains (one for the carb's overflow and one behind the mixture screw), finished the plumbing (as stealthy as possible), fired it up, passed my MOT and now I'm chasing a crazy issue, seems like flooding. I fire up the engine and it can't rev up above 1k rpm. Fuel tap to OFF and after a while it starts to rev up fine. But it still does that even if I leave it resting with the fuel tap on OFF position. Same thing without the pump. I'll try a different float and next will be a second carb (24 though). I'm pissed as hell and thinking of lighting it on fire...

















https://www.youtube.com/watch?v=Ji14oX9aJ68

Beautiful work Safis.
Makes me jealous to hear that motor running.

Assume you did not use a float bowl shim to raise it up.
Sure sounds like your float needle isn't seating - and it is just dumping fuel in.
I think this carb is new - so I would double check that the seat doesn't have a small burr on it that is keeping the needle from seating.

If you can't see in to it - perhaps take an old needle and press it in hard with your finger - then remove and see if it has an indentation mark it shouldn't.


Looking forward to hearing your report on riding it - and maybe a few cafe shots please.
*Edit - look for anything else the would cause the needle not to seat I would think. bad rubber on needle, flash on rubber tip, stuck needle, etc...

> out loud laugh <

Know the feeling well, have experienced it many times. Time to take a break.

Normally we plumb a bypass into the dellorto pump to stop overpressure. You could probably hide it into the carb box.

I know about the bypass but it’s not a pressure problem caused by the pump. It’s the same without the pump and even with the fuel tap to OFF. It looks like it floods the remaining fuel in the float chamber. Maybe I f@ked up the drilling or the carb has a factory defect. I’ll be investigating again on the weekend…

Even with fuel tap off, but works after you partially drain line and some of float bowl?
= fill level too high?
My money is on needle or seat - or some junk keeping the float from being able to go all the ay up and close the flow.

I've had this issue a few times too. Last time just a spec of black in the float valve seat. Scooter wouldn't rev and near impossible to ride any less than flat out.
The big give away was the large puddle of fuel on the floor every time it stopped. Tap was shutting off ok though. You might have two issues.

It’s the carb. Run a quick test. Took it out, filled up the float bowl and it starts “pissing” itself through the main jet. Checked the jet for sealing and it’s fine (perfect line around the “cone”). So, maybe the 2,5mm hole was too big or it’s just a faulty carb??

I won’t deal with it for now, took my second Pfizer shot today, so I’ll be taking it easy…

Change the whole float top from another carb to test it. Sounds like an issue with the float or something. All the SI carbs leak though the MJ when the level is too high.

Second shot is nothing like the first shot. Doubt you will even notice.

Second shot is a bear - until it’s not.
Glad you’ve found the basic issue.
Look forward to the first ride report.
Take it easy.
-cm

It’s not the float. I tried another and it still does it. Even if I just fill the bowl manually, it still drips though the MJ nozzle until the float is almost empty. Anyways, I’ll try the other carb and see how it behaves…

I agree. It’s different for everyone. My sister and brother in law had only the usual arm pain, two work colleagues were “obliterated” for 3 days in a row with high fever and general exhaustion. Will see how it goes. If it’s going to hit me, it’ll be probably be tomorrow…

Update time. New carb and CDI in and the revving problem seems to have disappeared. I know I shouldn't have replaced both at the same time, but I was frustrated and needed a "closure". I used red loctite for the venturi bolts but decided to also secure them. Especially the idle screw that loves to turn freely with the vibrations. Also, decided to ditch the pump and have a simpler setup (maybe I'll come back to this if needed). Made an extra bracket for the drain lines. Need to finish jetting (although sounds great with the current setup) but the weather's been terrible.

Also, managed to hit 14k rpm by setting the wrong pulses for the speedo sensor in the rpm menu...

That's a sweet looking pipe, I want one, not great for touring but it looks great.

hahaha.

Damn Safis - that is some mighty clean looking work.
The drain pipe brackets are first class.
The safety wires appear to be done by a man that has experienced bolts finding their way into the engine, or, a man that has had a lot of idle screws stolen while his bike sat outside the cafe. Either way - the whole thing looks very nice.
You and Craig are bracketing my badgery on both ends with your Malossi cases.
Impressive.

That is some clean scooter. Sure mine have never been that clean....ever.
If vibrating enough to turn the mixture screw, it would normally be that the crankshaft balance is off. Going to do engine damage in the long term.
Did you check the balance with the piston weight?

Balance is fine, the screw seems to be the problem. It's like it has no friction/ resistance with the slide. Maybe it's the spring that's compressed too much cause of the venturi…

Anyways, better safe than sorry…

A lot of the rotary cranks are balanced for Meteor pistons and the balance factor might be a little too high on a Malossi piston.

I have the same vortex on my PX200. Sure it came with a shorter spring in the kit. Long time ago.

What jets in the carb now?

wow surgically clean. On my Bajaj I don't use the spring with my T5 air filter and Pinasco lid it comes with a piece of rubber that fits over the idle screw and seals off the lid. When the lid is tightened the rubber compresses and keeps the idle screw tight.

If MV had a VaderKleen Award, you'd be a shoe-in, SaFiS.

Fucking high tech badassery. Love it. And yes... Vader is smiling somewhere about how clean that is.

I also love that no matter how high tech you get with these scoots, bailing wire (and duct tape) are always a viable option!

Please post a vid of the engine revving. I wanna hear that thing!

No spring with the kit. Pinasco does have one but it's way overpriced for basically the same thing...

Jetting, is 120/BE4/138 and 55/100 as we discussed before...

You guys!! You're making me blush

Well, my blue P is my pride and joy and also a black hole, where usually my wallet goes missing

The frame does need a respray though. Some spots have redeveloped a bit of rust and I have some chips here and there. Anyways, maybe next year...

Out of hibernation. We're getting warmer days. Did a few laps around the block (GoPro's battery was empty so no onboard video). Main jet looks like it needs to be dropped a bit. I have a 138 in atm so next will be a 135. And, I finally managed to set the speedo sensor. Only 2kms difference from a GPS so I consider it done...

Just a short static video for now...

https://www.youtube.com/watch?v=LImTQsRdjNA

She's a beaut!

Looks and sounds great!

Beautiful build safis.

Neighbors must be overjoyed.
🙂.

Gonna feel great getting back out on that one with its shinny bits.

Thanks Gents!! Thankfully, no neighbors around. I live in a small village and our house is a bit secluded. Only fields of wheat and olive trees around. And a few houses here and there...

Sounds ideal.

So many excellent sounding scooters around here these days.

I need to get myself a PipeDesign Auspuff at some point just to be one of the Cool Fast Kids.

Since I'll be needing a 210 kit for a future build, I was browsing the Malossi site today and got a deal even my supplier couldn't give me. I had some points to use, given from my previous Malossi V-One purchase, so a 28% total discount with free shipping was a no brainer...

Dang great deal!

Resurrecting this, the crank I was waiting for way too long, finally arrived. Imminent split and new calculations / setup...

I was not aware that was even a thing!

I was waiting for months for it to come back in stock (including the separate baseplate for the clutch which is made by MMW). I think this is how a proper crank should look like. Crank is made by Primatist in Italy. They make quality cranks and rods for Fabbri, Kingwelle, SIP, etc.

Sexy

Wow, that looks expensive. What stroke/rod? Which shop?

Not too much. It's 60/110. SIP branded made by Primatist…

https://www.sip-scootershop.com/en/product/long-stroke-crankshaft-sip-performance_45021620