TOPIC:

Hello all,

I recently pulled the valve cover and checked the valve clearance on my bike. I replaced a couple of the exhaust shims to bring clearance within spec. After putting everything back, the bike doesnt want to stay running. It is difficult to start, will not hold a steady idle. Once it is running the rpms ramp up to between 3500 and 4000 and hold until the engine is shut off. I pulled the valve covers and cams to make sure that I got the timing correct and put it back together. Still doing the same thing. Now a couple days ago I had to ride it home as the garage I was using had to be cleared. The ride home was rough to say the least. I think I may have done some damage to the engine. There was a lack of power on the ride, the engine was pulsing and had a difficult time staying steady at any rpm. Low rpm it seemed like it was misfiring, high rpm sounded like the engine was straining. Then I started hearing some knocking, sounding like something broke in the engine.

I know I should have ridden it, but had no choice beyond leaving it on the side of the road in a rough neighborhood. I am afraid I may have just killed my bike. I am beyond my knowledge level for repairing the engine. As I also live in an apartment with no garage, I have no way to try to do any more work myself.

So my question is, have I just destroyed the engine of my bike beyond what is worth repairing? I will need to take it to a mechanic for repairs. Is it worth any potential cost to repair the bike?

Thanks

Was the bike running fine before the problem occurred? Have you had it long?
I wouldn't assume the worst yet. It could be a fuel delivery problem or a bad battery or misfire or something. A motorcycle can sound really bad when running on 2 or 3 cylinders. Is there enough fuel in the tank?

Did you mix up the plug wires ?

Thanks for the quick reply. The bike was running decently before, had some clacking coming from the top end, the reason why I decided to do the valve clearance. I've had it for about 6 months. Plenty of fuel in the tank. The battery has a low charge. I did have to bump start it while testing it. I made sure to label the plug wires before I pulled them. Maybe Ill go pick up a trickle charger and see if a low battery could be the culprit.

First thing, check your plugs. Can you put up pics? They're right, misfiring or not at all can sound like a lunched engine.

The bike needs a good battery to run right as it provides the energy to fire the coils.
You may also need to service the points & timing advancer
(I don't know anything about points ignition, assuming that's what your bike has).

KZRider loudhvx has a couple of manuals on his motorcycle stuff page. --- see links in his signature.

When you get a new battery, be sure to properly service it before installing it on the bike.
I use a Ctek US 0.8 smart charger & VC97 digital multimeter.

Well off to get a new battery, thanks for your help. I will update soon

Start it cold, and feel the header pipes, to make sure all are getting hot at the same time.

I'm with Martin new battery to start with.
It ain't gonna run right if it doesn't have correct battery voltage.
Also unplug the head light when your testing stuff to keep
from running the battery down so fast.

There could be multiple problems, but a lot of stuff you can check is fairly doable,
even without a garage. The racing rpms could be a vacuum leak.
Is the stock airbox installed w a good filter?

So new battery. I tested the old one and it was definitely bad. Now it starts better, but is backfiring. When testing before riding it home the valves were quiet, but now I am hearing clacking from the exhaust valves. I will have to pull the valves again adjust some more. Im guessing the clearance is now too high causing the cam to knock on the bucket, and also causing the backfiring. Getting frustrated. Once again, thanks for the help, Id be going crazy without it

Again I got a crazy rattle when the engine is started. I removed the valve cover and rotated the crankshaft. As I rotate it, at two point there is a pop and the cam chain goes slack.