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Positive valve experience ??

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I saw many Valve issues threads, can it be that the same people are posting on each of them ? and sharing their bad experience.

Are they any people haveing the CRF250X for some time without problems ?

Please write about how long you have the bike, how many miles, riding hours etc.

I plan to purchase a new 2007 CRFX and wonder if the problem is so common or not.

Thanks

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I ran my 05 from new for nearly a year without problems, the problems happened when i put a hole in the side and lost all the oil. Lucky for me it nipped on the piston and stopped the bike before it did any real damage. After sending the head away and getting the seats cut and new valves installed it again ran for a fair period before they started to move.

I now run the bike give it the odd shim just to assist and as soon as the valves start to move alot get a new set put in. the cost is not that high. I may think about fitting stainless or getting a set of better titanium to try and will probably replace the seats next time.

All in all the bike is a pleasure to ride and if you race the things you have to expect to spend money. We used to race supermoto Quads with KX500 engines these required full strip and rebuild (gearbox inc) new piston and even had to replace the engine studs after 6 weekends of racing. That said the kx was giving 75bhp at the rear wheels of a quad.

Thanks to Honda for building this excellent little bike.

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i read a mag thats said honda has fixed all its valve problem for the 07 model. didnt say what they did tho.

Do not believe all that is in the mags... 905 is paid advertising in one form or another.

Honda made a few minor changes that may or may not help. Read up on the technical issues by myself, RHC, Kelser and others.

alot of guys get along fine with the CRF the way it is. It is a good bike but you need to take precautions with any hi revving 4 strokes. they need to be pampered.

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We've got over 2500 miles on our 2006 and the valves have not been shimmed and are still in spec.

Do the maintenance, stay off the rev limiter and they will work well.

Right on point.

I have over 200 hours on my head with no movement since break in. The valves were out of spec from the factory.

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I've had my 250X since 04, and have NEVER had any sort valve problem with it. Keep it maintained and it will do fine.

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I am of a different view of the valve issue from those who say that abuse kills the valves. Enough guys have posted here who have had the valve problem even when babying the bike, while other guys beat theirs mercilessly and rarely service it with no problems at all. Ron Hamp said something recently about a lot of color variation between new factory valves. I'm assuming it is caused differences in the thickness or application of the coating. Honda may or may not have fixed this issue, but only time will tell. Meanwhile, I am one of the guys who has the hourmeter, checks valves, changes oil, cleans the air filter and runs snake oil in the gas. Like many of the rest of you, I am willing to pay the maintenance price for this bike.

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1800 miles plus and has to be at least 200 hrs on the stock valve train and piston. I shimmed at 1700 miles and didn't get much out of that.I'm now running RHC's set up and a CP piston with an hour meter to see if they will last as long as stock.

Suposedly the 06 head was to have smaller valves and better seats.IDKN my freind has an 06 R and his right intake 0d at 20 hrs.I think it's still luck of the draw.It's not even my bike but I'm a little pissed this bike 0d so soon.

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We've got over 2500 miles on our 2006 and the valves have not been shimmed and are still in spec.

Do the maintenance, stay off the rev limiter and they will work well.

4 strokes were born to be on the rev limiter

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My 04 250X has had little clearance in the exaust valves since I got it new (way below spec). I replaced the valves this winter, and it seemed to be the same. What is this from? and is it bad to run it with so little clearance, it always seems to run great.

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I run my exhaust at .008''.per my mechanic.he says he sets some of his race bikes at .005 intake and exhaust.A little hard to start but makes more power.The tighter you run them the less valve slap you have.My bike starts fine at .008'' exh and .004''-.005''int.

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Ron Hamp said something recently about a lot of color variation between new factory valves. I'm assuming it is caused differences in the thickness or application of the coating.

I send out exotic materials for coatings every day from the shop I work at , and subtle differences from lot to lot fof the same materials come back with different colors. We use a anodizing process called Hard Coating which creates a surface thats really hard on aluminum.(it actually penetrates the material and builds on a coating) We'll make 10 parts out of the same material from the same supplier dipped in the same tanks and they come out looking different. My opinion is it's more base material related than coating related. As far as the seat material - I wasn't aware there was issues with them wearing......just the coating coming off the titanium valves then they fail. My experiance with premature valve failure was after sucking muddy water into my engine. I replaced the intakes after one zero'd at less than 500 miles and 750 miles later and they're still OK. One self inflicted failure has not made me think there is anything wrong other than one grain of sand between the the seat and the coated titanium valves will be the beginning of the end.

I have a friend with the same bike (05' crf250x)and he has 2100 well maintained miles on his original valves.

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My opinion is it's more base material related than coating related. .

Titanium is always soft & that's not going to change from batch to batch. Like all metal gets softer with heat too.

As far as the seat material - I wasn't aware there was issues with them wearing......just the coating coming off the titanium valves then they fail.

Correct.

If they went to Copper-berylium seats (not sure they did, Agent smith made it sound like something different) it's to help the valves. It's softer & has better heat transfer.

One self inflicted failure has not made me think there is anything wrong other than one grain of sand between the the seat and the coated titanium valves will be the beginning of the end.

I think you're absolutely right on this. I got to help a riding buddy of mine replace his valves (CRF450R) a couple times. Most of his riding was in the dunes. The stainless valves are holding up well though.

Another guy I ride with (ex MX racer) flogs his 250X constantly & has not had a problem. This guy brake slides into turns, leaves the throttle on with the clutch in & then lets it go when he's pointed in the right direction. Incredibly fast out of turns but I feel sorry for the bike. He's very meticulous about maintenance though & like I said has not had a problem.

:applause:

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I run my exhaust at .008''.per my mechanic.he says he sets some of his race bikes at .005 intake and exhaust.A little hard to start but makes more power.The tighter you run them the less valve slap you have.My bike starts fine at .008'' exh and .004''-.005''int.

Well my exhaust clearance is at .005 right and .003 left. I replaced my valves, and the clearance stayed the same. The old valves were fine and were sealing perfect. My dealer said it was perfectly fine to run it with that little clearance, but I want a second opinion. The bike starts great and runs fine.

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I've had my '06 for a year now. I only have 15hrs on it, I maybe rode it 7 times this year. And the valves are still in spec (LOL).

I'm going to sale it, so if anybody's looking for a '06??????

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Titanium is always soft & that's not going to change from batch to batch. Like all metal gets softer with heat too.

When I said I thought it was base material related - I was refering to the difference in color - that it might not have anything to do with the thickness of the coating.

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