421 Help please!

[TKJ421]

Alright guys I've got the shee back together and it's broken in. I took it out riding today and I'm pretty sure my jetting needs a touch up. I'm at 600ft elevation, I've got 160 mains 55pilots in my 35mm pwks. K&n pods, shearer sb in frames, vf4, and it's a ported cheetah running c12 at 40:1 I thinks this is all the info you guys will need to help. It's running hot, not overheating but shee starts to spit a little, it smokes a lot when revving or hitting the pb. My jetting has to be off somewhere, it doesn't really bog but something doesn't fill right until the power band. I tried launching full throttle and there was a little hesitation until high rpm?

 

 

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[Yvon Ladouceur]

I had same problem

 

 

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[twittle]

Did you do a leak down test yet?

[TKJ421]

Did you do a leak down test yet?

Yes I did it after a few days of heat cycles, everything's fresh and new.

 

 

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[Buffalo-Banshee]

Don't worry about the smoke its a two stroke ...

But did you sink your carbs? Is one pipe getting hotter than the other? Check that first

[twittle]

What needle and clip position do you have in it, timing set at? Do you have a temp gauge on it? My drag ported 421 cub with pretty much the same setup, (35 pwk's, k&n's, vf3's, inframe sheare's, timing at +6, mixing 114 oct @40:1) and pretty much the same elevation is jetted at 148 mains, 48 pilot, cel needle on the 5th clip position. I am still a little rich on my main's. I had it tuned on the dyno a few weeks ago and rode it pretty hard last weekend and it was running a little rich both times but I left it alone. Even after a lot of passes by me and my buddy mine never got above 165 degrees. Last year I had an air leak that I got sealed once but came back. Hope that helps.

[TKJ421]

Don't worry about the smoke its a two stroke ...

But did you sink your carbs? Is one pipe getting hotter than the other? Check that first

carbs in sync all the way around, I used the tool.

 

 

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[TKJ421]

What needle and clip position do you have in it, timing set at? Do you have a temp gauge on it? My drag ported 421 cub with pretty much the same setup, (35 pwk's, k&n's, vf3's, inframe sheare's, timing at +6, mixing 114 oct @40:1) and pretty much the same elevation is jetted at 148 mains, 48 pilot, cel needle on the 5th clip position. I am still a little rich on my main's. I had it tuned on the dyno a few weeks ago and rode it pretty hard last weekend and it was running a little rich both times but I left it alone. Even after a lot of passes by me and my buddy mine never got above 165 degrees. Last year I had an air leak that I got sealed once but came back. Hope that helps.

. Thanks man I'll mess around with the carbs today and see where it gets me

 

 

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[2sTrokeLove]

Same setup same elevation, I run 50p 165 mains runs hard, I still need to bump my main down and maybe pilot to 48

[2sTrokeLove]

Oh and dgk middle clip

[TKJ421]

Same setup same elevation, I run 50p 165 mains runs hard, I still need to bump my main down and maybe pilot to 48

Thanks man I dropped my main to 158, and raised my needle up 1.. I couldn't believe the difference it made all around.

 

 

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[sleeper06]

I'm with 2stroke love most around my end up between 162-165 main 48 pilot with force 3s so you might a bigger pilot ,drag ported bikes seem to like the d series needle 4th clip un ported likes the cel

[vulvafan537240]

55 pilot sounds huge. 48-40 IMO.