2012 yz250f troubles

[RideRedCrf-x]

Here's what happened. I was riding home from a friends house at about fourty miles an hour for around thirty seconds. When I got back to the house and put the bike in neutral I noticed a sound that sounded almost like a loose bolt rattling. When you give the bike gas it gets really loud. It sounds almost like some sort of chain is loose. I do not know where to start to find my problem so any advice on what to do or what it might be would be helpful. Thanks

[moleson10]

First thing I would check is the cam chain tensioner. When they fail the cam chain can jump a tooth on the cam drive and cause big expensive problems.

 

I'm not that familiar with the device on these bikes but since you said it sounded like a "loose chain" it certainly could be.

[RideRedCrf-x]

Thank you I will try that

[RideRedCrf-x]

I just started it up and within minutes the exhaust got red hot which it has never done before. This is symptomatic of a valve correct?

[oldnbold]

A cherry red exhaust while sitting on the stand is normal. You need to have air blowing across the radiator and the engine if it's sitting still for any length of time.

FYI, lots of information on this forum. Search chain slap, cam chain tensioner, cam chain. Compare your symptoms to what's on the is forum

Working on this bike is pretty simple. Get this bikes manual, read it, and buy about $250 worth of Harbor freight tools and you can wrench on this bike.

[RideRedCrf-x]

I have the tools. Just not the know how on this new bike yet. But yes thank you I will try that. Only thing that made me realize the cherry pipe was because it has never done it before and it say idling for way longer.

[RideRedCrf-x]

Oldnbold I just searched cam chain noise and the ones that they said was the cam chain do not sound like what my bike is doing.

[philwil44]

take off the rocker cover and have a look at the cam caps and make sure nothing is broken and all 6 bolts on the intake and 4 bolts on the exhaust caps are tights (10nm as per manual), check the tension on the timing chain also when you are there, make sure there is no slack or minimal movement, have you got the valve clearance checked recently?

[RideRedCrf-x]

Ok so I finally got time to take it apart and look at it. It was way out of time and the cam chain was loose. I put it back in time and manually adjusted the cam chain and it tightened up very good. Could my problem have come from the acct going bad and letting it jump a tooth and go out of time

[levi534]

keep an eye on you cam chain tensioner. i would have replaced it they do fail from time to time

[RideRedCrf-x]

I've got it back in time and now it is almost impossible to kick. All the valves are opening correctly I'm at a loss.

[RideRedCrf-x]

It's all back in time but still won't start. It will back fire every ten or so kicks but won't start. It won't coast start either. With it in time the valves are all tighter than spec. Any help or advice would be very apreciated

[bring the rain]

stop kicking it over and take it apart. ideally with someone who knows whats going on. ask someone to help while you learn. even if you give them some cash it will be cheaper.