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will your bike run if cam chain is one tooth off?

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I'm doing some "investigative work" here.. let's say a guy took out his cams, then when putting them back on he put the cam chain back on JUST ONE TOOTH off from where it should be. Would the bike run? How well would it run?

I'm imagining that it would indeed run, just not as strong..? anyone have any experience with this?

thanks very much

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the wr comes with it's exhaust cam 1 tooth off compared the the yz's. advancing the intake cam ~5 degrees (1.2 tooth) on the yzf makes more power down low and mid.

you need to be more specific. what bike, cam and which direction.

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If it is an auto decomp cam, you will lose much of the benifit of the auto decomp feature. If you can get it started, it should run, but may now be YZ or WR timed, depending which bike you have. However, if you go the other way, and your intake cam is off a tooth, it may not start at all, or flood out. Just guessing with the intake, but I did change number of teeth to YZ time--I went back to WR timing--power band seemed smoother to me.

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is the 250F motor an interference engine w.r.t. the valves and piston?

jim aka the wrooster

'01 wr250f

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this is a 2003 YZ250F, stock YZF cams.

"It appears" as though the curve is not as peaky, more spread out, but not as high as before the cams were removed! however some mods were done as well, and I'm not sure whether to blame incorrect cam installation or the mods; the mods are pretty foolproof (air filter, pipe, ignition, milled head), so I wouldn't think they would cause one to LOSE power; it's a nice power spread, but still.. just trying to figure out now if re-adjusting the cam chain on the cams is a good idea...? it seems like something to check in any case. I don't know which way the chain would be off, I'm only guessing that it IS off.. I reckon a trip to the 250F FAQ is in order here to see how to "check my work".

Wrooster I don't even understand your question.. :thumbsup: I'm not that bright with engines.

thanks for the help, dudes.. any other input is appreciated.

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his question was if the piston could hit the valves with too much timing change. Yep it sure can.

pull the plug, and take the valve cover off. Then spin the motor until the "I" lines up on the stator (on the compression stroke). If the cams are not timed correctly, the timing dots wont be horizontal with the head.

It's easy to install them incorrectly.

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:thumbsup: dont mess with what you dont understand,i read of more and more people messing up their bikes on tt because some people would rather tinker than ride,if you dont understand pay someone, :devil:

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I hear ya.. I'm going to do both. :devil: I'm going to look myself, but I have a friend who's a motorcycle mechanic who I think I'll invite over after everything's apart and I think it's cool to double-check my work. I'm a lousy mechanic, but I feel that since I used to be able to do all my own 2-stroke work, I need to learn how to do all the 4-stroke stuff... I'll get it! :thumbsup: I kinda like doing my own work, that's kinda fun too.. riding is MUCH more fun, but I get a sense of satisfaction after a job well done.

thanks very much!

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To answer your original question, yes it will run being off one tooth,and quite poorly at that! It was wayyy hard to start and and ran like there was a rag in the airbox! I'm not sure if it was off one tooth advanced or retarded. I learned my lesson, and no valve piston contact, thank god!

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