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Time for new valves .... where to buy ??

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I now have around 45 hrs on the motor (250R)

Intake valve (rt) is just out of clearance (.003)

I am planning on doing a complete top end.

What is the latest on valve recomendations for replacing

the stock ones. (Or should I just throw new stock valves and springs

back in ???)

How about the piston ????

Is there anything out there that outlasts the oem part ???

This is my first rebuild on a 4-stroke. So I appreciate any input.

I'm not complaining ... ( I love this bike) I knew about the

maintenence issues before I purchased it. I blame the guy who let me try his

new 250R one day for all of this work ! (sold on the first ride :cry: )

THanks for the HELP :cry: :cry: :cry:

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I am pretty much in the same boat as you. OEM is pretty cheao for pistons but I figured since it was apart I would slap in a Wiseco hi-comp piston. It is supposed to have some coating on the skirts to help it last longer (prob a gimmic). As far as valves I was going to run the RHC valves but havent been able to get ahold of him so its starting to look like stock exhaust, and Pro Circuit intakes and spring kit. While its apart you might also want to think about replacing your seats and also checking your valve guides!

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Thumper Racing has a stock diameter piston with the larger skirt design (same as the 270 piston with recent pictures on the site by HR). This might be another piston option if you want to stay with stock compression/bore specs.

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Actually Thumper Racing's piston is stock bore, but not stock compression... The stock compression on the crf250x is 12.9:1. The Wiesco made Thumper Racing piston is 12.0:1. This compression (12.0:1) is supposed to work better when using normal high grade pump gas. This is an issue for some people where 91 is the highest octane available to them locally. I just got this piston from TR today, $175 with shipping. It comes with piston, rings, wrist pin, and clips, plus it has the wide skirt design like the big bore piston. The part number is 9986M07800 for the crf250 78mm 12.0:1 4v dished piston.

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I was thinking about just shimmin it, but.....

The manual says rebuild at 15 hrs ( BS as far as i'm concerned)

Eric Gorr gives it 30 hrs.

So, I'm a little over 40hrs, and figured now would be a good time.

I have heard that if you wait too long, and major failure is just

waiting to happen.

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I would pull it apart and check the valves and seats and decide then if you need to replace them and have the seats reground. If it was me I would just get the stainless intakes with matching springs as well as have the seats reground.

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If your not experiencing any symptoms of excessive wear (i.e. hard starting), I would shim them first. Basic rule of thumb: if the difference between the new shim size and the original shim size is more than 10%, replace the valve. The springs are cheap, so if you do replace the valves, replace the springs (and the stem seals) at the same time. I order my OEM parts from Service Honda, personally I haven't found anywhere cheaper. I recommend getting the service manual as well, a lot more info than the owner's manual. I would also get in the habit of checking them every time you change your oil.

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I now have around 45 hrs on the motor (250R)

Intake valve (rt) is just out of clearance (.003)

I am planning on doing a complete top end.

Have you reshimmed before now and do you have any clearance measurements from before 45 hours? If you haven't measured before now, your valves may be fine as some are delivered tight from Honda (like my left intake) and many times, they settle in a little tight during initial break-in and then last quite a while after one reshim. I realize that with winter and all, you may just want to tackle the job and do the valves during some down time you may have, but it may not be necessary yet. Just a thought.

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