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08 xcf valves

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I have checked my valves and found that they are off slightly. Im going to adjust the vavles this weekend do I need any special tools. I have an 08 250 xcf w/ a big bore kit in it from KTM. I have 40 hrs on the bike everything seem to be running fine. I was just doing some routine checks and maintenance when I found my intake valves are at .089mm, specs are .10mm to .15mm and the exhaust are .12, and spec is .12mm to .17mm. My engine builder says to remove one shim per valve. He said when he built the motor he sent everything as close to the middle of the spec he could. He didnt say anything about any special tools. Anyone have any thoughts.

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A pen-type magnet to lift the shims is great to have. Also a good set of feeler gauges, I like the tapered ones. A micrometer (or the like) is mandatory to figure out which shims you need too buy.

I assume the builder meant to put thinner shims into the engine? Measure the shims and subtract the difference between the actual gap and what you want. For intakes, you should get shims about 0.040 mm thinner (0.13 mm - 0.09 mm). The gap will decrease with hours due to valve stretch and seating of the valves deeper into the seats.

Please allow somebody to check my post to see if I still have it right!!!

Cheers,

MrHix

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Yes my buddy has a micrometer to measure the shims. I like the magnet idea. So How many shims might I find sitting in the shim retainer. Im trying to figure out if I should buy a shim kit, or just wait and see what we need. The thing is we are planning on doing it Saturday morning christmas eve most store will close early if they even open at all.

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There is only 1 shim per valve. That is why you need to measure and then order the right shims. I don't think getting a "kit" is worth it. You will probably only use a few.

Cheers,

MrHix

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So How many shims might I find sitting in the shim retainer. Im trying to figure out if I should buy a shim kit, or just wait and see what we need.

I believe there should only be one shim per valve. Buying a shim kit would be an expensive way to go but on the other hand you won't be able to know what you need until you measure the existing shims. Do you have a service manual? The manual I bought for my '08 says to tighten the cam bridge to 18 NM. This is way too tight and some people have had the cams seize when the bridge was overtightened. The torque value most commonly discussed in the the various forums is 12 NM. After torquing the bridge and before releasing the tensioner you want to make sure the cams rotate freely within the chain slack.

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Yes my buddy has a micrometer to measure the shims. I like the magnet idea. So How many shims might I find sitting in the shim retainer. Im trying to figure out if I should buy a shim kit, or just wait and see what we need. The thing is we are planning on doing it Saturday morning christmas eve most store will close early if they even open at all.

There is only one shim per valve, you will need to buy new shims once you measure the old and calculate the what the new shim thickness needs to be

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Ok so just one shim. I'll double check the torque specs and will take your advise to not over torque and make sure the cams rotate freely before the cam chain tensioner is installed.

Edited by otter101

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Well just completed my first valve job this morning. Not as bad as I thought maybe I just was intimadated by doing it. Definatly needed a micrometer, magnet and a good torque wrench. I think the hardest part was putting the cam chain tensioner back in as I didnt remove the radiator or the hoses. I wish we could have video tapped it for you tube that would have been fun. The bike seemed to sound better and runn better, at least up and down the cul da sac. I wont get it out until nest thursday. The local shop just swapped out the shims so we didnt even need a kit or buy anything. So I treated myself to a new set of bark busters for a job well done.

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The local shop just swapped out the shims so we didnt even need a kit or buy anything. So I treated myself to a new set of bark busters for a job well done.

Your shop swapped you out! Mine charged $10 for one shim. I wanted to kick him in the balls!

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I realize this post is after the fact, so its for anyone else performing this task. I recommend using a clean, lent free rag to block off the timing chain cavity to keep small parts out of the engine. With the engine @ TDC I add locator marks with a marker on the timing chain and cam gears to help reinstall the camshafts. When you remove the lower camshaft bridge be careful not to lose the locator dowels that the bolts go thru. They might stay on the head or they might stay stuck to the bottom of the bridge then fall out on the floor. When reinstalling the lower bridge I used rubber bands to hold the cam levers up. The manual says to compress the spring tensioner for installation, then stick a screwdriver down to pop it out. I installed mine with it extended, seemed to work fine.

Edited by Aviator 1

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