Good Morning,
I've just finished building a Vespa PK50 with a Malossi Kit on, and I'm having real difficulty tuning the carb. My setup is below. I'd appreciate any help you can offer, and a standard routine for tuning, as I can't even get the scoot running well at the moment.
The setup is;
PK50 Casings, not ported.
Malossi 136 Kit,
Dellorto PHBL 25, with AQ266 atomiser, D22 needle, 50 slide, 95 Main, 42 Idle, 40 pilot
Simonini Down and Forward exhaust.
I have a selection of Jets, slide and needles to try, and I have tried Main jets from 115 down to 90, idle jets from 40-50. the 42 idles and start well. The 95 main is ok when the scoot is stationary, but when I take it for a test ride, the pick up is slow, and it dies when i ride it uphill. I've tried a 40 and 30 slide, but they are worse, similarly, a D26 needle is worse.
I've checked all the obvious fault finding stuff, like fly seal, air leak, timing, etc all are ok, so I'm convinced its the carb.
I was hoping you could find the time to have a read through and perhaps recommend a course of action. I feel I'm at the edge of my knowledge.
I appreciate any help you can offer,
Kind Regards,
Dan
Vesp PK50 Help
Try everything small frame on fbk or small frame forum
it's already circulating the smallframe forum 

Try scooter tips and fixes on fbk pages
- sean brady scooters
- Dealer
- Posts: 2040
- Joined: Mon Jan 05, 2009 12:09 pm
- Location: Ripon, North Yorkshire
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you say that your at the end of your knowledge ,and are it sounds pretty fed up of swapping bits endlessly (not to mention the cost of all the parts you have tried) and testing ,oh and petrol and time .
so why not just get in on a dyno and set up ?,as thats thats the only course of action i could recommend to you
so why not just get in on a dyno and set up ?,as thats thats the only course of action i could recommend to you

Sean Brady Scooters - 01765 690 698
Can't find anyone near Portsmouth/Southampton are.
- sean brady scooters
- Dealer
- Posts: 2040
- Joined: Mon Jan 05, 2009 12:09 pm
- Location: Ripon, North Yorkshire
- Contact:
not sure who is in your local area at all ,so maybe you would have to travel a bit ,but the result would be worth it i,m sure.
Sean Brady Scooters - 01765 690 698