Got a big bore, now what?

[capecod400ex]

I bougth the big bore kit its on it's way now what should i do find a shop to bore the cyclinder out then what do i need any thing else's it comes with, 12.5:1 Compression. Includes piston, rings, wrist pin, circlips, top end gasket set and Sleeve. do i have to buy any thing else's.?!!

[nacs400ex]

If you have the money, get:

FCR carb
agressive cam
hard faced rockers
CRF450 timing chain
heavy duty valve springs
....?

[capecod400ex]

is this all stuff i need for it to work rigth

[Steven]

No, you don't neeeeed that stuff but a drop in Hotcam for another $125 will really bring that kit to life.

Speaking from experience though, you should buy new cylinder studs. I got mine from Honda for about $5 each X 4. Then have your machinest retap the holes in the cylinder to thier bottoms... he can get another 3-4 threads taped for more holding power.

Also, if the kit comes with a fiber head gasket don't use it. Order a metal one from cometic. It will be much stronger.. You'll need it with that compression.

Dont forget to rejet.

[capecod400ex]

what should i rejet to i have a K&N jet kit in thaire now, and what will hapend if i dont have the holes taped will the head blow off. and if i do have it done do i get new stock head studs or longer one's

[Steven]

the OEM studs will work fine. get the holes taped though, high compression likes to pull studs. it will take the machinest another 15 minutes to do it.

start rich on the jetting an lean it out as you need to. without an air box lid start about 170 to 180 main jet. i run the 170 in the summer and depending on how cold it is, i run the 175 or 180 in the winter here in florida.

try removing the choke from the carm and run a #40-45 pilot.

[capecod400ex]

ahh with out the choke i cant get any thing out of that in the winter , i ride form the temp like -10 to like 100 so i kinda need a choke but thanks for the good ideas , every one this is the first BIG mod i have done i rather do it rigth one's not wroung twice , thanksfor the good advice and help.

[JD400exrider]

What kit did you buy. Is it the weisco piston 440 kit

[twisted threads]

How much money do you have???
You need to get a cam and I would get some porting done. If you have the $ get a FCR carb trust me its night and day difference

[capecod400ex]

i did get the the weisco piston 440 kit and how much si the porting

[capecod400ex]

Hey, am going with a HOT CAM camshaft whitch one the stage two or one thanks.

[JD400exrider]

I have heard the 440 weisco kit is misleading on the compression ratio. You might want to do a search on here to find out more.

Porting will be around 150-350 depending what type of porting you get done and where you go. If you can afford the FCR 39 it is a night and day difference. If not a stock carb mod for 125-175 depending where you go should also give a good difference in throttle responce and power.



Good Luck with the project.

[capecod400ex]

AHH, ....yea i jsut read some post's about hot cam and every one was geting all :mad: and craping on them so ethier should i trust them or how can i get a hold of a HRC cam, thats what thumper raceing used on thaire 440 in dirt wheel's and i notcied u had one in your info ,but idk i really need help.

[JD400exrider]

I was talking about the compression ratio of the weisco pistons on the 440 kit. I have heard there compression is not as high as advertised. Call C& D racing and talk to colby. He should be able to shed some light. It may be fixed. :confused:

The hot cams had some problems with the flange fitting loose. I believe the problem is solved. The new ones come with the flange on the cam. I would think you should not have a problem with a new hot cam. Call C&D racing on the cam.

The HRC cam you can get from service honda. They are more expensive than the hot cam but it is a quality honda part ;) :cool: