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Checked valve clearances for the first time...

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Just pulled my topend apart after the bike became difficult to start. Exhaust valves were within spec, but at the tighter end of the range. Intake valves were both out of spec. Just to confirm, if the clearance is too low (tight?) that means the valve isn't closing all the way and therefore I don't have the compression I should, correct? That would cause the bike to be hard to start. Is the goal to get the clearance right in the middle of the range or is it better to go to the 'loose' end?

Sorry, I know there are ton of valve threads but none that seem to answer this question definitively.

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A little more info...left intake (as you're sitting on the bike) had nearly zero clearance, and the right had about 0.08mm. Both had 300 shims. Went to a 295 on the right and it's in spec now (about 0.13). I went to a 290 on the left and still cannot fit a 0.05 feeler gauge in it. Gonna try a 280 next.

Is it normal to have a valve so tight as my left one is? With such little to no clearance the valve is basically always open. I'm hoping this isn't a sign that something is going bye-bye on me... I don't race and can't remember ever hitting the rev limiter.

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How many hour on the bike? Chances are your intake valves are going/gone.

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Probably 25 to 30 hours on the bike...not hard hours either. This is pathetic.

So if that one valve is on its way out, do I have to replace all of them or just that one? Do I have to have a new seat or have that one recut? Should I use oem valves or aftermarket? Do they have to be lapped? 2-strokes are looking pretty attractive at this point...

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25-30 hours is not out of the question depending on how you ride it and maintainance practices. I am at 32 hours without any signs of movement. There is always a chance that you may have been out of spec from the get go and could have caused there wear you are seeing.

You will want to do both intakes, I think you said they were both out of spec so both will need to be replaced. I wouldn't bother with the exhausts since they did not move. You will want to inspect the seat for wear, have someone who works on these do that. If the seat is wore you will trash the new valves fast! I don't have an opinion on the choice of valve.

Check your ring end gap on the piston while you have it apart as well.

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you know, I agree it is pathetic. both honda and kawi are rediculous with valve issues. I've had my yamaha 450 for 3 years and the valves never went out of spec. This kawi is only inspec when its not running and just done. turn the crank over once and its out again.

I would love this bike if kawi would actuly design the engine to last more then 5 hours

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what year is your bike? if its a 05 the intake valves always goes first mine just has after about 50 hours.

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Is post for an '04? And you got 30 hours on the valves? If that is the case you got 15 more than I would have expected.

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Nope, '05. Just talked to the tech at my dealer and he said just shim it and ride the rest of the season, but keep checking every so often to see if it moves again. Said he's seen many that moved that much but stopped after they were reshimmed. I'm in Maine so I only have a couple of months left at best, and I'm only riding maybe 2 hours a week.

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Remember to use OEM valveshims, since they are titanium like the OEM valves. Steel shims will beat up them badly. :thumbsup:

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Thanx for the tip. I'll reshim and keep an eye on it. Love the bike but looks like a change to blue might be on next years agenda...

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What about those Hot Cam shim kits? are they As good or better than the OEM shims?

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What about those Hot Cam shim kits? are they As good or better than the OEM shims?

i used the hotcams shim kit for my 06 and it worked fine. right intake was out of spec. it was .0037 and should have been .0039. 60 hours on the bike and valves specs are good. i noticed that on my bike you cant go by the timing marks. if you do it will have a false reading for some reason. :thumbsup:

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If you don't go by timing marks what do you use to make sure your timing is correct? I'am asking because ome day my son said the bike was not running right and the marks were off. I had just shim'd it and i know the timing was spot on.

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If you don't go by timing marks what do you use to make sure your timing is correct? I'am asking because ome day my son said the bike was not running right and the marks were off. I had just shim'd it and i know the timing was spot on.

well i used the timing marks the first time i reshimmed and they were worked. then after i reshimmed they never lined up with tdc. the cams were just about to open the valve at the tdc mark so i did it right before. the bike runs good and no weird noises or anything. i dont know what happened. this is 10 hours later

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Not sure what you mean by 'can't go by the timing marks'. There are 2 marks on the flywheel. One is for TDC, and the other is for ignition timing. Set it at TDC (helps to take the plug out so pressure in the cylinder doesn't push it off the mark). With the cam lobes facing away from each other the marks on the cams should line up with the top of the head. There is a great article with pics here

Ran mine the last 2 days after reshimming and no problems. Runs a ton better!

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I was wondering if you have to completey remove the carb to get at all the bolts on the cam chain tensioner?? Any tricks to avoid removing the subframe and carb to get at the cam chain tensioner?

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you can get it out without movin anythin but is a little fiddly but what i do somethimes is just undo the carb brackets and turn the carb on its side.

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I thought you had to remove hex bolt in the center so you could release the tension by turning a screw inside like most other tensioners, but this one doesn't work that way. All you have to do is take the hex bolt and spring out of the tensioner, and then remove the tensioner (two 8mm bolts). Just be sure not to allow the tensioner to lengthen from its current setting before putting it back in or it will be way too tight.

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