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bigthumper155

02 yz426 valve helpppppppppppp!!!!!!!!!

10 posts in this topic

hellow all, im new to the threads and thanks for having me. So here goes. I got a 02 YZ426f about 6 months ago, it is a great bike with many new upgrades, the guy i got it from took great care of the bike and put a new top end on the bike before i got it. ( i got the paper work on the rebuild) it had 2.5 hours on the bike when i got it. (hour meeter on the bike was installed with rebuild) the bike also has a hot cams cam on it, and a shop adjusted the valves with the new cam. The problem is, i took the bike out started it and warmed it up, made a few passes on the street just messing around and the bike died, it didnt make any funny noises or anything, itryed to start the bke and it wouldnt start, i kicked and kicked and it wouldnt start, i looked it over and couldnt find anything wrong with it, i did a compression test on it and its a big ZERO. the motor has 4.5 hours on it. can someone give me a link to valve specs and the step by step adjustment or have an idea whats going on.

sorry this post isint real organised but i need help thanks all.

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With the auto decomp hotcam installed you will not get much compression at all if any. you need to do a leak down test to see if everything checks out ok. That will tell you if your rings and your valves are sealing and still good. I can't think of the specs off hand for the valve clearance but try searching and you will find many threads with lots of info.

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thanks, how would i go about doing a leak down test?

also i looked for specs but i couldnt find any, i also looked for a shop manuel

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You didn't look very hard. The very first thread at the of the forum index is Common Threads. At the bottom of the second section, it lists links to downloadable manuals.

The Hot Cams auto decompression cam will not lower cranking compression to the level of not "much compression at all if any", and it should feel like kicking a big cube 2 stroke. Look up the cam timing inspection process and check it.

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hellow all, im new to the threads and thanks for having me. So here goes. I got a 02 YZ426f about 6 months ago, it is a great bike with many new upgrades, the guy i got it from took great care of the bike and put a new top end on the bike before i got it. ( i got the paper work on the rebuild) it had 2.5 hours on the bike when i got it. (hour meeter on the bike was installed with rebuild) the bike also has a hot cams cam on it, and a shop adjusted the valves with the new cam. The problem is, i took the bike out started it and warmed it up, made a few passes on the street just messing around and the bike died, it didnt make any funny noises or anything, itryed to start the bke and it wouldnt start, i kicked and kicked and it wouldnt start, i looked it over and couldnt find anything wrong with it, i did a compression test on it and its a big ZERO. the motor has 4.5 hours on it. can someone give me a link to valve specs and the step by step adjustment or have an idea whats going on.

sorry this post isint real organised but i need help thanks all.

Did you turn your fuel on? :excuseme:

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you said you got it out! How long has it been sitting since the last time you rode it or started it? Try fresh gas and a new plug. Keep it simple before going into thinking it may be a valve or timing issue. Check too see if you are getting fuel to the carb. Spark at the plug. etc.

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i started it every week i didnt ride, i put a new plug in it, and checked the gap, i have a hot start leaver on the bars, mr hot start i think , i pulled it and it didnt make it start, it has fuel, and i even tryed starting fluid, no luck, it does have spark though

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i started it every week i didnt ride, i put a new plug in it, and checked the gap, i have a hot start leaver on the bars, mr hot start i think , i pulled it and it didnt make it start, it has fuel, and i even tryed starting fluid, no luck, it does have spark though

You should only pull the hot-start if the engine is hot.

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