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When & how do i adjust my valves? I have a TRX450r '05. It's almost 2 months old.
 

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I do know how but not when, other than when you check them and they need it.

You have to take the rear fenders, gas tank and valve cover off. Then check the clearances. If any are off, you need to remove the cam holder. The cam and exhaust rocker comes off with it. The adjustment is done with little shim pucks that sit under the rocker arms on the exhaust valves, or under buckets that run under the cam. Be careful not to drop any of them into the motor.

Anyway, once you get them out, you have to buy new ones of the right size to adjust. They're labeled with numbers like 170, 172, 175 etc. Those mean 1.70mm, 1.725mm, 1.75mm etc. Each .025 mm is about .001". See which one came out, add or subtract, reinstall a new one and remeasure.

Also, don't forget to check the decompressor clearance while you're in there. It's the old-school screw and jam nut style.

The shims are about $6-7 each (at least around here) so you usually tear into it, go buy 2 or 3 near the right size, then finish.

I pulled mine down, checked them and reassembled in much less than an hour. Of course I'd been in there before for the HRC kit.

 

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Hey charlie,

the guy was just asking to ajust the valves. In alot of quads, youre suppose to get the valve clearence cheques after break-in buy youre honda dealer
 

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I thought I was answering his question. I explained HOW to adjust the valves. I didn't know what to tell him about when. I sure sometime after break-in makes sense but they should stay in spec for quite awhile after that.

FYI, mine were still in spec when I put the HRC kit in after several tanks of gas.
 

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If you don't have the factory service manual you might want to get it. You also might want to brush up on your feeler gauge usage. The clearances per factory spec are pretty tight and require some "feel".

If your not comfortable with the process take it in...when I went to the local dealer looking for different shims when I installed my HRC kit he told me that the last time someone was looking for shims he sold them a complete cyl. head a week later. :lol:

I traded my stock shims with 2 tanks of gas on them to the local dealer even up for the ones that I needed. The service manager was gone for lunch and later told me that they usually charge about $4 for a trade of shims.

BTW I got the only shims within 150 miles of were I live!
Wouldn't have rode that weekend without a little luck!!!!

After at least a dozen tanks of gas my valves are still quite....I will check them before I put it away for the year (or maybe next spring...lots of sled work to do this fall!).
 

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Originally posted by clutch@Aug 22 2004, 10:09 PM
(or maybe next spring...lots of sled work to do this fall!).
What you doing to your sled? I ride an '01 Summit 700, stock except a hot dogger.
 

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Gunner - If you have to ask how to adj. valves it is probably better to take it to a shop or have a friend that know's how to do it help you, as making the wrong move here can cause some running issues or even worse. Having the valve clearence to loose can cause some valve damage, will sound like crap, and will casue premature cam wear. On the other hand, if the clearance if too tight, your valves will not seal properly, and depending on how tight they actualy are, you'll never get it to start when it's warm if you get it to start at all. So it's real important to know exactly what your doing, plus, this is a shim under bucket set-up which means if you dont get it right the first time you have to tear everything back down and do it again....

What you want to do is remove the valve cover and spark plug (To make it easier to rotate the eng). Remove the access hole plug on the ign. cover. Now with your socket wrench rotate the engine and watch the cam at the same time, pick which valve your going to check and rotate the engine until the cam is no longer depressing the valve, at this time insert your feeler guage and get your clearance. Here's a little tip, If the recommend clearance is .002 - .004 then get the .002 feeler gauge and the .005 gauge out and try to insert the .002 gauge, if it fits than your clearance is not to tigh, if it does'nt fit then your clearance is too small and you need a smaller shim... Then try the .005, if it does'nt fit then the clearance is not to big, but if it does then you need to make the clearance smaller which will require a bigger shim.... Catching on???

Take your readings for all the valve and then disassemble, make sure you mark which shim came out of which valve. Sometimes you may even be able to swap shims from one valve to another if it applys to your clearance needs.

Also remember that when pulling the buckets out of the head to try and use your finders to lift the bucket up. Some people like to use some sort of magnet but this could magnatize the bucket which will lead to the bucket collecting metal shaving which could lead to serious damage. Also, when lifting the bucket, the shim sometimes likes to stick to the inside bucket, so make sure your watching out for that so you don't have a shim dropping down somewhere it should'nt be...And lastly, when inserting the new shim, make sure to put some oil on it and place it in the retainer with the side endicating the size of the valve facing up.... Happy Motoring... Oh, Did I mention to make sure to re-set the cam timing properly, probably best to seek assistance, as that is a whole other topic....
 

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Originally posted by superfloguy@Aug 24 2004, 11:31 AM
Gunner - If you have to ask how to adj. valves it is probably better to take it to a shop or have a friend that know's how to do it help you, as making the wrong move here can cause some running issues or even worse.
I agree, leave this kind of stuff to the pros
 

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Originally posted by UFOmile450r+Aug 24 2004, 11:49 AM-->
<!--QuoteBegin-superfloguy
@Aug 24 2004, 11:31 AM
Gunner - If you have to ask how to adj. valves it is probably better to take it to a shop or have a friend that know's how to do it help you, as making the wrong move here can cause some running issues or even worse.
I agree, leave this kind of stuff to the pros [/b]
I tend to agree though I'm not sure it requires a "pro" but rather someone with mechanical experience/know-how. I meant my rather brief guide as a reference to someone who is already familiar with and comfortable with adjusting older-style valves (screw & locknut).

In other words, before I owned a 450R, I had no idea how the valves clearance was set on bucket over shim style cams. I read a thread months ago somewhat like this one and it was enough for to understand the process.

If you aren't completely comfortable with doing it after reading these posts, I'd suggest having it done.
 
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