Any body know what would cause this?

[400eXz]

On my 06 450er I was riding at a buddies house about a week ago and it has always been hard to start when it's hot Im pretty sure it's the jetting. But I started it and let out of clutch and gave it about half throttle and it start booging and popping and snapping. I shut it off and when I tried to start it back the battery was acting like it was almost dead and I had to roll start it to get it to start. Still started booging stuff. Then the next day we put a new spark plug in it because I thought that I had just burnt the tip off of it. It won't even hit if I try to start it with the battery. My friend thought the motor jumped time. And now when I try to start it its acting like it's blow up. So we tore the motor down and everything looks fine but were gonna go ahead and put a new piston on it since it's tore down. But does anybody know what could cause this? I'm thinking the motor isn't getting gas at all? Not the right fuel/air mixture I'm not sure at all to be honest.

[CJM]

Valves.

[audioworks04]

Sounds like valves, but also sounds like your jetting was never right to start with. When was the last time you checked/adjusted the valves. You should be checking them about every 10-15 hours of ride time. The stock valves on the 450r's are pretty weak and are know to fail.

[400eXz]

I traded a dirtbike for y 06 450er and rode it for about 19 hours since I've had it. But god only knows how long it was before the guy that had it adjusted the valves. When I look at them none of them look bent at all does that still mean that it could be the valves? Also they had some magnet type things on top of some of the spring and I noticed that they were on only 2 of them and not all 4 of them. Could that be the problem?

[01boneless]

valves are definitly out of spec....

[DnB_racing]

Originally posted by 400eXz
I traded a dirtbike for y 06 450er and rode it for about 19 hours since I've had it. But god only knows how long it was before the guy that had it adjusted the valves. When I look at them none of them look bent at all does that still mean that it could be the valves? Also they had some magnet type things on top of some of the spring and I noticed that they were on only 2 of them and not all 4 of them. Could that be the problem? are you sure there arnt 2 shims stuck under the valve lifter buckets?

if 2 shims have been removed for valve lash clearance to be in spec, then you have some serious wear and you might need more then just valves, possibly new head or get yours fixed and ported,along with,new valve springs, valves, cam, cam chain, gaskets, seals, seats, guides

[400eXz]

Whats a valve lifter bucket? Dont call me stupid I'm on this I'm still learning lol

[DnB_racing]

Originally posted by 400eXz
Whats a valve lifter bucket? Dont call me stupid I'm on this I'm still learning lol on the intake valves,under the cam there are the 2 intake valves that have a little cap that rides over the valve springs, the should also be 2 shims between the bucket and end of the valve

[hrc450er]

I hope your friend knows what he is doin or this things will never run again. Go buy a manual from honda for it

[xcracer416]

Originally posted by hrc450er
I hope your friend knows what he is doin or this things will never run again. Go buy a manual from honda for it

what he said. if your buddy called them a "magnet thing" then im sure you need a manual or a shop to take it to. bend a valve because of not being sure of whats going on will cost you more in the long run.

[desratt]

Take a good look at the valve springs. Also the valve decompressor mechanism. Make sure it moves freely.

[TheLane]

Dont discourage the guy everyone!

you CAN do this yourself but you will need a service manual. Go on some of the TRX only forums and you can find ones to download for free. This manual will show you how to tear your motor down to individual peices and put it back together. Valves arent a hard job, you just need to know what your doing, and you need to ESPECIALLY watch your timing if you took the cam out. make sure you put it back together in time or you WILL trash your motor.

Like I said, its easy to do...you just need to know what your doing.