banshee4201 Posted January 11, 2009 Report Posted January 11, 2009 i am building a 4mil 73mm bore 485 cheetah. I was just wondering if i should run big bore or small bore oof pipes. I run 600ft. dirt drags. Thanks for any input. Quote
Onesickcrewcab Posted January 11, 2009 Report Posted January 11, 2009 I have a 485 cheetah. You def want Big Bore. Huge difference when i went from small bore to big bore pipes! Quote
dajogejr Posted January 12, 2009 Report Posted January 12, 2009 Matt Shearer will tell you small bore unless you're running a hill. Big Bores were designed for the 535cc cheetahs and up. Quote
Onesickcrewcab Posted January 12, 2009 Report Posted January 12, 2009 Matt Shearer will tell you small bore unless you're running a hill. Big Bores were designed for the 535cc cheetahs and up. Hill or not, hands down the BB worked better for my 485. The small bores choked my motor down big time. Considering the bore on the 535 and the 485 are both 73 I think the big bore is a better option. Everyone is entitled to there own opinions, but I can tell you from experience with the 485 BB is your better option. My cylinders were also drag ported by LC performance. Porting will also play a roll in which pipe you choose to go with. Talk to your builder to see what he recommends. I don't run a track to give you an time slips, but I can tell you I went from getting beat by 7 bike length with small bores, too being right next to the same bike with big bores. Approx 400ft races. Quote
dajogejr Posted January 12, 2009 Report Posted January 12, 2009 Hill or not, hands down the BB worked better for my 485. The small bores choked my motor down big time. Considering the bore on the 535 and the 485 are both 73 I think the big bore is a better option. Everyone is entitled to there own opinions, but I can tell you from experience with the 485 BB is your better option. My cylinders were also drag ported by LC performance. Porting will also play a roll in which pipe you choose to go with. Talk to your builder to see what he recommends. I don't run a track to give you an time slips, but I can tell you I went from getting beat by 7 bike length with small bores, too being right next to the same bike with big bores. Approx 400ft races. Good to see a first hand account. I run Big Bores on my 300ft sand drag 10 mil cub (465cc) It runs very well, too. I do want to try some small bores, but you hit the nail on the head....builders will have their own opinion with their specific porting... Quote
Stellar Performance Posted January 12, 2009 Report Posted January 12, 2009 I even run big bores on my 7mil 442 cub. I started with small bores and it ran fine, but I noticed my motor had more usable power with the big bores. I might have lost a little bit on the very top rpms, but what I made up over all, I will not be going back. Quote
dajogejr Posted January 12, 2009 Report Posted January 12, 2009 JT has run small and big bores on his drag ported FAST 4 mil cub. He prefers the big bore pipes as well... Quote
bansheeseat$$ Posted January 13, 2009 Report Posted January 13, 2009 I to run BB on my 421.Same thing,sb didn't run as good as the BB. Quote
gasmask34 Posted January 13, 2009 Report Posted January 13, 2009 i would say if your have a shop build your motor let them tell you which pipes to use. i was told that if your motor is under 450cc than you want to use sb but. i've had friend with big and small motor do a sb/bb switch to see which pipe works better. sometimes it was the small bore then other times it was the big bore. 1/8 drag racing... so to me it all depends on the person who builds your motor. unless you buy both sets of pipes and do your own testing...just my two cent...lol Quote
dajogejr Posted January 13, 2009 Report Posted January 13, 2009 i would say if your have a shop build your motor let them tell you which pipes to use. i was told that if your motor is under 450cc than you want to use sb but. i've had friend with big and small motor do a sb/bb switch to see which pipe works better. sometimes it was the small bore then other times it was the big bore. 1/8 drag racing... so to me it all depends on the person who builds your motor. unless you buy both sets of pipes and do your own testing...just my two cent...lol That 450 thing is a TOTAL myth...I don't know where or who started it...but it is a myth. I can't speak for CPI....but Matt Shearer himself said the 535cc cheetah is the motor the pipe was designed for (big bore) smaller than that cc it should use a small bore pipe. I've seen sb on 10 mils and bb on stock stroke, stock bore bikes... It's builder and motor preference.... Quote
gasmask34 Posted January 13, 2009 Report Posted January 13, 2009 That 450 thing is a TOTAL myth...I don't know where or who started it...but it is a myth. I can't speak for CPI....but Matt Shearer himself said the 535cc cheetah is the motor the pipe was designed for (big bore) smaller than that cc it should use a small bore pipe. I've seen sb on 10 mils and bb on stock stroke, stock bore bikes... It's builder and motor preference.... not to step on any toes but i believe i just said that... Quote
dajogejr Posted January 13, 2009 Report Posted January 13, 2009 i was told that if your motor is under 450cc than you want to use sb but. You did...I just wanted to dispel this rumor...because numbers tend to stick in others minds more than anything... Quote
shanYE west Posted January 13, 2009 Report Posted January 13, 2009 My cub ran VERY strong with small bores.. switched to big bores.. and seemed stronger in the dunes but I didn't get a chance to really get into it.. and I couldn't make the last few races to get some slips.. soo.... Quote
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.