Time for Piston & Rings........valves too???

[reborn_450]

Getting ready to replace the piston & rings in my 04' CRF450, looking for any input (brand, compression, etc.)

I think I will redo the valves also at the same time. What should I replace and what type/brand do you recommend????

Want to get all the input I can before I start laying out some big $$

On top of that, I'm looking hard at the Hinsen Clutch/inner hub/basket/pressure plate....any opinions???

Thanks everyone!!!!!!!!

[Supermoto]

hey,we used Vertex 12.5:1 high comp pistons this year,and they seem to be great..as for the valves,just re-shim and theyl be fine.

[Faded]

Reborn,

FFR and RHC have time and time again recommended the JE piston for its tighter piston to cylinder wall clearance over other brands (Wiseco, etc.) and increased compression. No worries in relation to fuel quality with the high comp JE piston, premium pump gas will be adequate.

Now would be an excellent time to replace the stock valves. If you want some more reading on why you should replace them and not just re-shim, click here. As far as replacement valves go, stainless steel offerings from Kibblewhite (Eric Gorr) and Ferrara (Ron Hamp) seem to be the best alternative out there offering up to 300+hrs of operation with only scheduled valve clearance checks. Due to the SS valve's increased weight they will require upgraded springs and retainers, something that should be done even with factory valves.

Another item to look at inspecting/replacing would be the cam chain tensioner.

You can't go wrong with Hinson clutch components.


In jest, remember to break your bike in the "hard" way in order to redeem your ticket for a free 10% power increase. :

[Supermoto]

glad you saw the light...

[Woody_393]

Just finished the top end on my CRF, and here's what I did.

RHC Intake and Exhaust retainers, and valve springs.

RHC Intake Valves (The exhaust are already SS, and he checked out my Exhaust valves and they were fine).

JE 12.5 Compression piston.

If you go with RHC intake valves, due to the dish in the valves, you lose roughly .5 in compression ratio (so a 12.5 is really a 12 when used with his valves).

I think His SS valves weigh about 5grams more then the Ti OEM's.

I also replaced my cam chain tensioner as well with an '04 model. However, since you already have an '04, I don't think it's necessary, but you could if you wanted to, since the '02-'03 were the ones that had/have the problem. And the fix is either manual chain tensioner or '04 chain tensioner.

Bates has had RHC's intake valves and springs for about 20 hours and so far so good.

FWIW, that's what I did, and I felt very comfortable with my decision (thanks to my trust in FFR's opinion).

[reborn_450]

WOW!!! Thanks everyone, great input!!!

[reborn_450]

oh yeh, call me nieve but what is FFR, RHC & JE ??

[Faded]

RHC = [Only registered and activated users can see links. ]
JE Pistons = [Only registered and activated users can see links. ]
FFR = Tryce W., ATM name FFRacing11x

The RHC stuff Woodrow is reffering to is made by Ferrara.

[Woody_393]

FFR = FFRacing911
RHC = Ron Hamp Cycle (Ron Hamp) http://www.ronhamp.com
JE = JE - It's just the name of the piston. Kind of like Wisco is wisco.

[reborn_450]

Originally Posted by Faded

RHC = [Only registered and activated users can see links. ]
JE Pistons = [Only registered and activated users can see links. ]
FFR = Tryce W., ATM name FFRacing11x

The RHC stuff Woodrow is reffering to is made by Ferrara.

THANKS!!!

[Woody_393]

Yep, it's made by Ferra, but it's at RHC recommend, and I'm pretty sure he had a hand in getting them created.

[Faded]

Originally Posted by Woody_CRF

Yep, it's made by Ferra

Ferrari? Wood, did you spring for Testarossa replica plastics too?

[Woody_393]

Faded, you're an a$$