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Hello guys, so I have this 02 crf450r that absolutely will not start. I have good compression,air,fuel and spark. I did get it to pop off twice but died instantly, so I pulled valve cover to check valve clearances, exhaust were in spec and intakes were .006 and .005. I noticed that when I got the bike to tdc on compression stroke, the right side timing marks lined up but the cam appeared to be off by 3 teeth. So, I re-timed the engine and now right side marks and cam marks are lined up perfectly.. but now it won't even fire or try to start. So I pulled off the peep hole for the ignition timing and when on tdc, right side and cam lined up, the ignition marks are nowhere in sight. Almost like 180 off? This must be my problem as its not sending spark at the right time..? My question is, can I time the cam off of the flywheel marks and disregard the Right side counterweight marks? Just want to get this thing running.. and yes I had already removed and inspected the flywheel and the key is not sheared. Any info is much appreciated! Thanks in advanced!

Welcome to the site !!

It could be that your timing chain is stretched , or your tensioner is not working/locking in place , if all is good with the chain , and the cam is facing the 2 O'clock position (facing rear) , and the notches on the cam gear are lined up with the mark on the head , then the Ignition mark on the flywheel and the Balancer gear (clutch side) should all be aligned together as well

Can you give some history as to how you got to this point ???

Did you just buy the bike and it was not running ??

Did you just rebuild the bike and this is just after reassembly ??

Was it running fine then just quit starting ??

Was it having issues but ran , then was taken apart to diagnose and/or repair , then these separate symptoms came into play ? , or were these symptoms the cause of a tear down/inspection ??

Did you do the work ?? or did someone else say they did work on it prior to this ???

Most importantly ..... Do you have a Owners or Factory Honda Service Manual ??? (if not i can make available a Factory Service Manual for you to download if needed)

This info will help us diagnose the issue , but we just need more input as to what led up to the symptoms to eliminate or factor in events and steps taken to cause the symptoms

Bought bike not running. Guy said just needs carb gone through as it hasn't been ran this year yet. I cleaned it and didn't change anything. Motor was rebuilt 50hrs ago with paperwork. Bike would just backfire once in awhile and would jump start but die... so I thought valves. Checked valves and they're in spec. While doing so, noticed that the cam was 2 teeth off from tdc compared to the right side crank marks.. so I re-timed . (Forgot to check ignition like an idiot so idk if it was on with the ignition when 2 teeth off... but now that I changed the cam to tdc with the crank it won't even backfire or bump start... also do not have a manual. A download would be much appreciated. Thank again! And yeah tensioner and chain are in good shape and working properly.