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Discussion Starter #1
I think my bike needs a valve adjustment but everyone tells me that there never out of spec when the manual says "26,000 miles" my bike has slowly lost a lot of power over the summer and I've tried doing a tune up/throttle body sinc. I have 25k miles and I'm kinda broke so I'd rather not Pay to check them if I don't have to.
 

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I can only speak to my own experience, I check the valves on my 00 R1 every 10k miles or so and they were in spec up to 60k miles when I decided to do a rebuild for other reasons. Of course, YMMV, if you are losing power it could be for many reasons. Checking the valves is not a hard job, IMHO, buy the Motion Pro angled feeler gauges, download the factory manual, and just give yourself 2-3 hours - you'll learn a lot in the process. If you find them out of spec, re-shimming is a MUCH bigger job than just checking, and not for the faint hearted. Check my rebuild videos in my signature, I do a full valve check and reshim in one of them.
 

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Discussion Starter #4
Thanks man. That says a lot about Yamaha 60k miles and there still in spec. I guess I should suck it up and try checking them.
 

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Discussion Starter #5
If its not the valves what else do u think could be killing my power? I've done a full tune up but its still no where near what it should/used to be. it never smokes out of the exhaust so I don't think there's any blow by, sometimes It's a little hard to start when it's hot but not bad.
 

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I'm not performance tuner, but I'd say it's really hard to say tirekiller... power is a very subjective thing unless you have dyno numbers before/after or something like that. If you are going by feel, it's a lot harder to really know what is going on. But, for some suggestions, I would do a little more baseline diagnosis

1. a compression test, or better, a leak-down test. See where your cylinder compression is really at
2. air/fuel reading w/ a dyno run and a carb inspection. If your carbs are off you could be losing a lot of performance. I know it doesn't seem likely that the carbs go from good, to all of a sudden a problem, but it is possible - jets clogged, diaphram punctured, who knows.
3. Did you make any changes along the way, any chance something robbed you of performance?

Where do you think you are down on performance? Low end grunt? mid-range? Top-end? Equally everywhere?
 

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Discussion Starter #7
I lost it in the mid and top. Last year I was able to break the tire loose on the highway now it struggles to do it going 20mph :( now that u Mention it I did put a new tank on that had a good amount of rust in it. Thanks man I'll grab a new filter and see what happens.
 

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Discussion Starter #8
I pulled the tank off to look for the filter but didnt see it. I guess its in the tank. I had a full tank of gas and didn't feel like dumping it to check the filter so while I had the bike apart I sprayed the f**k out of the throttle bodies with throttle body cleaner. Took it for a test ride and it seemed to do the trick.
 
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