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cave weta
3rd April 2009, 12:04
Hey guys, which years CRFs are notorious for their valves letting go and can later valves be substituted?

honda_power
3rd April 2009, 12:29
aparantly all of them, or at least the 250's to 08, not sure about 09 but they didnt change much. but iv had 04 and 06 models and iv never had any trouble with the valves... think i got them replaced once in the 250+ hours my 04 did, and that was just cause it was re-built

B0000M
3rd April 2009, 12:31
aparantly all of them, or at least the 250's to 08, not sure about 09 but they didnt change much. but iv had 04 and 06 models and iv never had any trouble with the valves... think i got them replaced once in the 250+ hours my 04 did, and that was just cause it was re-built

i know a lot of people with CRF's, never heard of anyone who has ACTUALLY HAD valve problems. ive heard the story before tho

Firefight
3rd April 2009, 13:16
Most 250 4 strokes like the crf, kxf and rmz etc all have titanium valves that need replacing at sum stage hondas were normally gud for about 100 hours or so b4 the need to replace, sum seem to go on 4 ever, never had any probs with mine, so who knows ??


F/F

kezzafish
3rd April 2009, 13:29
just keep checking the clearances, According to my manual i'm supposed to put $800 worth of valves in mine after 40 hours. But they haven't moved 0.02mm since i put the last piston in 60 odd hours ago so the valves have probably done in excess of 180 hours without a drama. Just remember... everyone who has the capability to make money from you is a shit talking, granny bashing, kiddie fiddling reincarnation of satan

telliman
3rd April 2009, 14:26
i just had my valves done, 130 hrs on an o4!

cave weta
3rd April 2009, 14:47
Just remember... everyone who has the capability to make money from you is a shit talking, granny bashing, kiddie fiddling reincarnation of satan

That is exactly why Im here! a friend has had her bike in and out of the shop. and 10 hours after the last full top end rebuild it shit a valve and now just one ride later it appears to have done another!

Im just trying to ease her pain.

B0000M
3rd April 2009, 15:27
i can sell her a complete head in good condition. comes with a free complete bike apart from head.

cave weta
3rd April 2009, 15:33
i can sell her a complete head in good condition. comes with a free complete bike apart from head.

$200 is the going rate - awesome deal - send it to me. Ill pay you when I see you!:Pokey:

B0000M
3rd April 2009, 15:35
yea, i want a bit more than that for my one aye

Robert Taylor
4th April 2009, 17:11
just keep checking the clearances, According to my manual i'm supposed to put $800 worth of valves in mine after 40 hours. But they haven't moved 0.02mm since i put the last piston in 60 odd hours ago so the valves have probably done in excess of 180 hours without a drama. Just remember... everyone who has the capability to make money from you is a shit talking, granny bashing, kiddie fiddling reincarnation of satan

Valves and valve keepers. Every 4 stroke 250cc MX bike made is highly stressed. These components eventually need to be replaced due to stress hours, not so much because of measurable wear. People need to absorb that fact. Plenty of these bikes around that have gone bang because highly stressed parts have been run for too long. That is the price to be paid for wanting more and more performance and its very much not a case of a manufacturers conspiracy in wanting to sell you more parts.
If you ride like a pussy you may get significantly extended life out of the valve train. On the other hand if you are on or near the rev limiter constantly that will foreshorten the life of those components significantly. Its also fair to say that there are a lot of so called mechanics out there who should be working on nothing more complicated than weedeaters and edge trimmers.

cave weta
5th April 2009, 15:22
Its also fair to say that there are a lot of so called mechanics out there who should be working on nothing more complicated than weedeaters and edge trimmers.

Mmmm... my thoughts too Robert, these guys are costing her a small fortune!

honda_power
5th April 2009, 17:27
Valves and valve keepers. Every 4 stroke 250cc MX bike made is highly stressed. These components eventually need to be replaced due to stress hours, not so much because of measurable wear. People need to absorb that fact. Plenty of these bikes around that have gone bang because highly stressed parts have been run for too long. That is the price to be paid for wanting more and more performance and its very much not a case of a manufacturers conspiracy in wanting to sell you more parts.
If you ride like a pussy you may get significantly extended life out of the valve train. On the other hand if you are on or near the rev limiter constantly that will foreshorten the life of those components significantly. Its also fair to say that there are a lot of so called mechanics out there who should be working on nothing more complicated than weedeaters and edge trimmers.

yes and no, my old bike was ridden hard, even rode the thing to work during weekends full-noise. no probs. some bikes seem to just go and go, others arnt so lucky