Big Bore Kits?

[TRX450R014]

Could someone tell me where to find info on big bore kits.I plan on buying a kit but I am not sure what the best setup would be.I have HRC kit,HMF BB PIPE.I want more power but I still want it to be reliable.any advise would be appreciated.

[dunebuggie66]

mine is at nmotion as we speak, getting their full race 520 kit. go to www.nmotiontechnology.com .

[jeepeater347]

I would look into the ESR 480 kit. Its a pretty good price and should still be reliable

[Icrashed]

FST 500 works for me.

[TRX450R014]

Thanks for the responses guys,I have been looking at some of the kits available
and the fst 500 seems to be what I am looking for.Hey Icrashed(greg),did you have the hrc cam installed before 500 kit?If so,how much more power did the bore kit give you?also do you have the
12:1 piston?I am really interested in the fst 500 but I would like some real world input before I lay down the cash.Thanks again.

[29FTEX]

The FST 500cc w/ 12:1 piston is comparable to a stock bore 13.5:1 with similar cam and exhaust. Not counting head work.

I've had both of these set ups and others who have raced and had dyno pulls, show that the two set ups are comparable. The FST 500cc should edge out the stock bore set up, but not by much, if any.

The FST set up won't require race fuel, but is more expensive than just buying a piston.

It comes down to can you afford the race fuel needed for the high compression stock bore piston.

Good luck with whatever your decision may be.

[Eddiesanders250]

get the bore kit from this kentucky guy its in dirtwheels its a 520. i think its the biggest they make.

[400exrider707]

Originally posted by Eddiesanders250
get the bore kit from this kentucky guy its in dirtwheels its a 520. i think its the biggest they make.

I'm pretty sure I saw some 570 CRF's so I would assume the 450R could go up towards that number too with a different cylinder. The bike was putting down something like 70 horse to the rear wheel!!!!:eek2: You would need some major cajones to ride that beast!

[Icrashed]

Originally posted by TRX450R014
Thanks for the responses guys,I have been looking at some of the kits available
and the fst 500 seems to be what I am looking for.Hey Icrashed(greg),did you have the hrc cam installed before 500 kit?If so,how much more power did the bore kit give you?also do you have the
12:1 piston?I am really interested in the fst 500 but I would like some real world input before I lay down the cash.Thanks again.

Yes, I did run the HRC kit before the big bore. Believe me you wont be disappointed in the FST big bore.Power delivery is harder everywhere with the big bore kit.
And yes I was running with the 12:1 piston. The nice thing with the FST, is you can run super unleaded instead of race gas,which is a lot easier on the pocket book.:)

I beleive the OTD price for the FST is about 500.00, after the refund for the core charge.

My current set up is the FST big bore with a 13.5:1 piston.It really runs well to but Its hard to tell how much faster it is over the 12:1 piston.Also the 13.5:1 piston is a one of a kind and MAY not be reliable.Time will tell.:D

[Eddiesanders250]

Originally posted by 400exrider707
I'm pretty sure I saw some 570 CRF's so I would assume the 450R could go up towards that number too with a different cylinder. The bike was putting down something like 70 horse to the rear wheel!!!!:eek2: You would need some major cajones to ride that beast!

ya ok maybe not the biggest but how do i know about that stuff i ride a 250R.

[dunebuggie66]

that "kentucky guy" your refering to i believe is actually a kansas guy, and they are nmotion.