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big bore or small bore


banshee4201

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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.

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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...

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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

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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....

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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...

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