tried the cam mod but my quad wont start turs over funny also . I only wet one tooth clock wise on the exhaust cam. Is it possible it was already done?

 

put it back the way it was and it runs fine must be done already is my guess. After I put it back the way it was I thought that I could of done a compression test to see if the exhaust and intake were opening at the same time but it was to late. Any thoughts?

 

Any one have any ideas Help! want to know what I did wrong.

 

Unless you bought the bike used it shouldnt be done already.

Are you sure you are retarding the exhaust cam?

 

Well I followed the instructions as I am facing the gears on the cams I turned the left cam one tooth to the right. Then I put it back together and it turned over hard so I put a battery charger on it and it still would not fire. Checked the plug it was wet so I know it had fuel. Got a little nervous so I put it back the way it was started up fine. Did I do something wrong? The one on the left is the exhaust I hope!!

 

If you are on the shifter side of the bike, yes the exhaust cam is the one on the left. Its the one towards the front of the bike.

 

Thats what I did. should I try it again? Maybe I am missing something.is there any way to tell if its done by looking at it?

 

Did you buy the bike new and has anyone else worked on the engine.

 

Bought The YFZ and the raptor brand new from Nielsens in chicago. Big store.

 

Then the cam mod is not already done. Search "cam mod" or yfz cam in the yamaha forum and you should find some good instructions, I've seen them but I dont remember what thread. There are also good instructions at Bluetrax_.com in the yfz forum. Throw another x where the _ is.