440 valve job?

[Dustin075]

I installing a 440 kit and i have been thinking of doing the valves also. Do they need to be done with the 440? If so what type of valves should get, the stockers or aftermaket?

Thanks

[REPOMAN]

i use stockers until they go bad. since you have the thing tore down just lap them and make sure they are straight and throw them in.

[REDRIDDER]

Well when doing a top end rebuild i would also take a close look at the head and check you valves, seats,valve guides,seals...but yeah when i did my rebuild last spring i went threw the whole head just about, i replaced the valves with kibblewhite,replaced the valve springs (kibblewhite),vavle guides (stock) cam chain (CRF HD CHAIN) had the seats done new valve seals ect...basically everything was new with the exception of the rocker arms.sorry a little off topic but when i did my rebuild i made sure that i wasnt going to be doing it again any time soon.Does your quad smoke any now? if so and its not blue i would look into the head look at the valve seals, seats, guides and the valve them selves.

[Dustin075]

No the quad ran good before the rebuild. All my friends have 450 so i wanted to get a little more out of her. A little off topic but what is the deal with the timing chain?

[REDRIDDER]

The deal with the CRF450R timing chain is that it can take more abuse than the stock 400ex's,their is less stretch with the CRF timing chain and its a lot cheaper than the stock 400ex timing chain it is also like an 1/8inch wider i believe.It's just some added assurance for bigger bore engines.I use one because I found out that four stroke tech was using them on their race engines so if their doing it I'm doing it.their explanation was the same as i told you,less strech,wear and added assurance.

[Jmtx86]

Sorry to thread jack, but my 400 smokes a little at start up and its not burning oil. Also it has a some what loud ticking noise coming from the motor, im thinking its the head, is this normal or should I be looking into a top end rebuild?

[REDRIDDER]

Originally posted by Jmtx86
Sorry to thread jack, but my 400 smokes a little at start up and its not burning oil. Also it has a some what loud ticking noise coming from the motor, im thinking its the head, is this normal or should I be looking into a top end rebuild? check your valve clearance and your cam chain tensioner if the spring inside breaks the chain will make a ticking noise, smoke at start up could be your valve seals,seat or guides.

[Dustin075]

What year should i look for for the crf timing chain? Should i also get the tensioner from the crf?

[REDRIDDER]

Originally posted by Dustin075
What year should i look for for the crf timing chain? Should i also get the tensioner from the crf? Get the 2002 crf timing chain and no you dint need the tensioner its not interchangeable only the timing chain is.

[Dustin075]

I have a 05 if that matters, dont think it does. Edit : i call my local honda dealer and i need to what size crf to order the chain. also new valves or leave them be and clean'em up?

[REDRIDDER]

Originally posted by Dustin075
I have a 05 if that matters, dont think it does. Edit : i call my local honda dealer and i need to what size crf to order the chain. also new valves or leave them be and clean'em up? .................................................. ........................................., CAM CHAIN part #... how bad are the valves?
14510-MEB-670

[Dustin075]

I bought the quad used from a buddy and he had beat it pretty hard, and i have trail rode the crap out of it. The valves are carboned up pretty bad. No smoke on start up or on accel though.

Thanks for the part number.

[Honda_Matt]

Originally posted by REDRIDDER
.................................................. ........................................., CAM CHAIN part #...
14510-MEB-670

That part # is for the tensioner, not the chain.

[REDRIDDER]

Originally posted by Honda_Matt
That part # is for the tensioner, not the chain. oh crap hope he didn't order that yet sorry the #s are right next to each other but this is for sure the right one CHAIN, CAM (112L)
14401-MEB-671.

[Dustin075]

Dont worry I got it straighten out.