Jetting directions for Keihin PWK 28 on 172cc AC Piaggio


Pia Maxiscooter FTW
Hi All,

I'm setting up my Keihin PWK 28mm on my SKR125. I'd like to have some jetting directions.

Setup is:

Malossi 172cc AC stock
Jollymoto 172cc kit exhaust
Keihin PWK 28mm
Open air filter
Malossi straight manifold
VL13 tuned.

Can someone give me any general ideas?

I'd like to know main jet size, pilot jet size, but most importantly the needle type.

I found out there are more or less 3 needle kits available on the market.

The 4 needle kit without needle type indication
The 10 needle kit consisting of HKJ, HLJ, JJK, JJL, JJM, JJN, JJQ, JJS, JLJ, KLK
And the 10 needle kit consisting of N68A, N68B, N68C, N68D, N68E, N68F, N68G, N68H, N68J

Any ideas are much appreciated, this way I know what needle jets to order specifically for the maxi engine.

Thank you in advance.
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Pia Maxiscooter FTW
As no one seems to have an idea, I will update the thread myself :D . There is not much information on the web on this subject so someone might find it useful.

I found out that the Keihin PWK might not have been the best choice for my engine, as the stock pilot jetting and needle are too rich.

The carb is now jetted with 150 main, 35 pilot, some strange Mikuni needle, and 3.0 slide. It runs, but is way too rich.

I have ordered a 125-148 main jet kit, 32 pilot (OKO, smallest available) and 2 needle sets, BGM and OKO.

Finetuning of the carb setup will probably be done on a rolling road with air/fuel ratio meter.

Keep y'all posted :)
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