Andreb84 Posted March 26, 2014 Report Share Posted March 26, 2014 i just bought a shee that looks to be set up for the 1/4 mile. it has a 4 mill crank, ported stock cylinders, v force 4 reeds, cpi inframe pipes, athena cool head, 39mm pwk carbs and 16/41 gearing this bike is all top end my goal is to try and make it a little more well rounded.im no expert on this but i think 39mm carbs are WAY to big for the set up i have.in an attempt to give the bike a little more bottom end i went down 1 tooth on the front sprocket and theres still no take off now im thinking it has to be the carb any advice at all on this will be much appreciated Quote Link to comment Share on other sites More sharing options...
RagunCajun Posted March 26, 2014 Report Share Posted March 26, 2014 Is it drag ported? If so, maybe it's best to get ride of those cylinder and get a serval cub or another set of stock cylinders and have them ported for different power delivery that's more broad and comes on the pipe earlier. Quote Link to comment Share on other sites More sharing options...
Andreb84 Posted March 26, 2014 Author Report Share Posted March 26, 2014 im not sure if the cylinders are drag ported but i do know that the cylinders are on their final bore.most ppl say that you lose bottom end when you go to a bigger carb i dont wanna buy a new set of cylinders only to find out the carb was the issue in the 1st place. Quote Link to comment Share on other sites More sharing options...
Zillaguy Posted March 26, 2014 Report Share Posted March 26, 2014 I'm running stock carbs on a ported 4mill stock cyl.. What type of riding are you wanting to do? 39mm is too big IMO unless you're drag racing, only... I'd so no bigger than 33-34mm if you want an all around kind of bike... A lot of guys are running bigger carbs like that, but I don't see the advantage... Unless you're WOT all the time.. You get crisper/snappier throttle response with a smaller carb... But, if your cylinders have exhaust port timings 198* or higher, chances are it's drag ported, and you won't have the bottom end power you're looking for.. Quote Link to comment Share on other sites More sharing options...
sheerider11 Posted March 26, 2014 Report Share Posted March 26, 2014 I'm running stock carbs on a ported 4mill stock cyl.. What type of riding are you wanting to do? 39mm is too big IMO unless you're drag racing, only... I'd so no bigger than 33-34mm if you want an all around kind of bike... A lot of guys are running bigger carbs like that, but I don't see the advantage... Unless you're WOT all the time.. You get crisper/snappier throttle response with a smaller carb... But, if your cylinders have exhaust port timings 198* or higher, chances are it's drag ported, and you won't have the bottom end power you're looking for..No. I have 35s and my bike is just as crisp as anyone else's. 35s are a good all around carb IMO for a 4 mil. I see them and cpi's the most recommended set up for trail/dune/play bikes that are ported 1 Quote Link to comment Share on other sites More sharing options...
Andreb84 Posted March 27, 2014 Author Report Share Posted March 27, 2014 lol pretty opportunistic about my riding spots i need a bike that does everything decent..but right now this bike is no fun at the trails at all i actually parked it and broke out the 250r the last time i went.i think im going to look into getting a smaller carbs i hear alot of ppl run built motors on stock carbs maybe i'll go down to 33's or 34's depending on what i can get the best deal on....i dont think theres any other way i'll get good all around power on the bike unless i do that or either go for a cheetah cub kit Quote Link to comment Share on other sites More sharing options...
sprinklerman Posted March 27, 2014 Report Share Posted March 27, 2014 lol pretty opportunistic about my riding spots i need a bike that does everything decent..but right now this bike is no fun at the trails at all i actually parked it and broke out the 250r the last time i went.i think im going to look into getting a smaller carbs i hear alot of ppl run built motors on stock carbs maybe i'll go down to 33's or 34's depending on what i can get the best deal on....i dont think theres any other way i'll get good all around power on the bike unless i do that or either go for a cheetah cub kitIf it's that horrible, it's not the carb size.Maybe jetting. Maybe the porting. Maybe the head design. But not the carb size. Sent from a van down by the river 1 Quote Link to comment Share on other sites More sharing options...
registered user Posted March 27, 2014 Report Share Posted March 27, 2014 im betting its the cylinders is where your problem is. especially if someone raised the exh to high. makes it bog like a pile of crap when launching and it may have a hard time staying on the pipe. if you ride in sand the problem will only be worse. Quote Link to comment Share on other sites More sharing options...
sheerider11 Posted March 27, 2014 Report Share Posted March 27, 2014 It is not the carbs. There is a stock stroke Rudy Kurtz motor that is hanging with 4 mils with 35s and CPI. 15/41 gearing with 8 paddle haulers. The rider is about 230. Far from a drag port too. Quote Link to comment Share on other sites More sharing options...
Andreb84 Posted March 27, 2014 Author Report Share Posted March 27, 2014 im betting its the cylinders is where your problem is. especially if someone raised the exh to high. makes it bog like a pile of crap when launching and it may have a hard time staying on the pipe. if you ride in sand the problem will only be worse. it does bog when you try to launch it and thats my main problem....lol iv'e already raced the bike several times and every single race i always get smoked on the hole shot...to the credit of my shee 4th gear is an absolute monster for whatever reason i always seem to catch up and win.i think i have it narrowed down though its either my cylinders or its the carb is to big.but my question now is even if i kept the huge carbs how are they a benefit when i dont know anybody running a shee with carbs that size.even if i changed the cylinder would i have the same issue?? Quote Link to comment Share on other sites More sharing options...
do-work-son Posted March 27, 2014 Report Share Posted March 27, 2014 Find a builder before waist a lot of money and time ..I Spent a year and a lot of parts and money fighting a port timing issue. Two sets of carbs two sets domes coils Cdi reeds flywheel nothing fixed my low end bog .. Now I'm going to a bigger carb and having the ports fixed.. Not saying your is port timing but unless there something wrong with the carb it self I bet you have other problems .. What jets you have in it? Are they sync ? Quote Link to comment Share on other sites More sharing options...
sprinklerman Posted March 27, 2014 Report Share Posted March 27, 2014 .i think i have it narrowed down though its either my cylinders or its the carb is to big.but my question now is even if i kept the huge carbs how are they a benefit when i dont know anybody running a shee with carbs that size.even if i changed the cylinder would i have the same issue?? Dude.... it's NOT your "huge" carbs. You may not have them tuned right, sure..but it's not the size. check the rest of the engine and electrical. Sent from a van down by the river Quote Link to comment Share on other sites More sharing options...
Larry's Shee Posted March 27, 2014 Report Share Posted March 27, 2014 What pipes you running? Quote Link to comment Share on other sites More sharing options...
Andreb84 Posted March 28, 2014 Author Report Share Posted March 28, 2014 What pipes you running? Quote Link to comment Share on other sites More sharing options...
Andreb84 Posted March 28, 2014 Author Report Share Posted March 28, 2014 Cpi in frames Quote Link to comment Share on other sites More sharing options...
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