What carb R U running on > 350cc's

[wes350x]

Im having issues of course with my jetting with my FTZ plot-topped motor, 387cc. I have a PWK 40.5mm carb and cant figure out the jetting, I read all the charts and pretty good on jetting my this is killing me. I have a 190 main, 8 slide, 52 pilot. I have tried a ddj, cel and dgh?, and still seems really rich midrange and doesnt hit powerband correctly. Anyway what size do you guys run on a bigger engine.

[latheboy]

I am running a 38mm on a 350pv. The cylinder is mx/tt ported so i dont see a need to go any bigger. I wouldnt want to lose low/mid range with a bigger carb. BTW, I am in running a DDJ needle in the 4th from top, 185 main, 50 pilot. Could maybe run a 48 pilot, but its very close. Note that jetting is also subject to your track condtions,track size and riding style. For instance, I could run a richer needle, and a smaller main if the track didnt have any real long straitaways. Some racers used to do that back in the day. Maybe to conserve fuel? I dunno.

[addictedtomud]

I have had alot of luck with much smaller main jets in the 350cc range with PWK 38 and 39 mm carbs. Usually end up in the 170 - 180 range on the main.

With a bigger carb, like a 40.5 on the same motor I have been in the 140-150 range. I live in Ohio BTW don't know what elevation but I ride in the woods, not alot of wide open throttle.

So I suspect the 190 main may be too fat!

[methyman]

My 370cc motor I ran a 44 lectron on gas. Really easy to tune. Packard Ent knows how to set the lectron carb up!

[wes350x]

I talked to a guy at an ATV shop today and his friend used to have mybike on methanol and he said they had the same tuning issues when they tried a stock ignition as Im running. I put my cr back on today and tried to troubleshoot it, I think the exciter coil may be bad if my meter was right. Now I have to find one asap!