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Adjust valves or don't bother?

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Hey all, I checked my valves today on my '06 YZ250f and my intakes have tightened all the way up. Last time I checked them 18hrs ago(I know I probably went alittle long between adjustments) my center one was tight at .04mm so I shimmed it. The other two were in spec at .13mm. Now one of the outer ones is .03mm the others I can't measure as my smallest gauge is .03mm. Exhaust has been rock solid and haven't moved the three times I've checked them. So my question is I think I'm gonna just replace them in the off-season this winter but I'd like to ride this weekend. Should I even bother shimming them when I may start tearing my top end down in acouple of weeks anyway? Probably only be an hour or two of riding on a little corner track. Thanks.

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You may have to resort to the old push n bump-start method as they close up, so just be aware. I wouldn't ride very long.

It still started fine except for the first start of the day last time I got to ride but it was about 40 or 45 degrees out. Once it was warm started first kick.

I probably shouldn't ride it but I hate to spend the money for shims to ride it one time then tear it down. I may pick some up though just to be on the safe side.

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all depends on how much you ride and how you ride.

if you dont rev the snot out of it all of the time and dont ride much, shim it and have fun for another year.

if you do bounce the rev limiter a lot, then new valves are needed in short order.

how many hours are on the valves?

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If you cannot fit a .03mm feeler gauge, then you most likely have zero clearance. The valve may not even be closing all the way. For this reason it is advisable to adjust the clearance before riding the bike again. Have several shim sizes available as you don't know what size you need.

You will likely need to remove and install the cam twice. First with a smaller shim in there just to get a measurement to determine the correct size.

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all depends on how much you ride and how you ride.

if you dont rev the snot out of it all of the time and dont ride much, shim it and have fun for another year.

if you do bounce the rev limiter a lot, then new valves are needed in short order.

how many hours are on the valves?

I've put 18hrs on it since probably late April/early May. I'd say I'll put between 20 to 30hrs between now and this time next year. I'll be riding 2 years in March and rarely if ever hit the rev limiter. Mostly just play ride MX. No idea how many hours are on the valves but from talking to the previous owner when I bought it I'm pretty sure thet're the original valves. I'm thinking they have alot of hours. I may go pick up some shims tomorrow and wait till Feb. to see if I win that KX250F from MXA before I dump money in it.

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I've put 18hrs on it since probably late April/early May. I'd say I'll put between 20 to 30hrs between now and this time next year. I'll be riding 2 years in March and rarely if ever hit the rev limiter. Mostly just play ride MX. No idea how many hours are on the valves but from talking to the previous owner when I bought it I'm pretty sure thet're the original valves. I'm thinking they have alot of hours. I may go pick up some shims tomorrow and wait till Feb. to see if I win that KX250F from MXA before I dump money in it.

They picked the winner earlier this week.

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They picked the winner earlier this week.

Oh, I didn't think they were drawing till Feb. I guess I didn't win. I haven't heard anything from them.:bonk: Oh well I got a subsciption to my favorite moto mag out of the deal.

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Oh, I didn't think they were drawing till Feb. I guess I didn't win. I haven't heard anything from them.:bonk: Oh well I got a subsciption to my favorite moto mag out of the deal.

My mistake, I was confusing different kx give-away's .

It was Motosport that just gave one away.

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My mistake, I was confusing different kx give-away's .

It was Motosport that just gave one away.

Sweet I'm still in.

Back to the valves I was gonna get shims but the Yamaha shop changed their hours and was closed when I got there. I only need two as I already have the value I need for the one that is at .03mm from a previous adjustment.

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I got my shims and adjusted the valves. It rained and I couldn't have rode the weekend in question from the original post anyway. Thanks all.

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