internal engine questions

[RedRider55]

We just bought a 95 300ex as a fixer upper. When we bought it, it would run, but i would never go over 3 mph as if it had a governer or lost it's compression. Now, it doen't even start. It will act like it's not getting any gas, but it is.

I now have the engine taken apart and have a few questions. How do I take the valves out and check them for problems? If it's not the valves, what else could it be? Any further input would be helpful.

[hondardr4life]

It most likely is low compression, but your valves could need lapped.

[RedRider55]

what do i look for to see if there is something wrong with the valves?

[440exnacsracer]

if it is that serious, you will be able to see something wrong just by taking the head off. there may be damage to the valves, but most likely, this is compression

[Fortman_400]

to check the valves while the head is off u compress the valve springs, and check the valve and valve seat faces and see if there are any large indents, if there are, u need a valve grind. they shouldn't have knotches worn into them at all, they should be straight machined surfaces.
then check ur rings, if ur compression is really bad, hope it ain't ur piston and rings otherwise u got sum $$$ to deal with

[Aceman]

What I would do is pour some either some solvent, brake/carb cleaner down the intake and exhaust ports and see if it leaks out between the valves and seats into the combustion chamber. This of course is done with the head off. If it leaks, remove the valves and see if they are pitted where they seat. Look at the seats also. If they look good you might be able to lap them. Reinstall and check with solvent again. I would also take your cylinder and piston into a machinist and have them miked. If its still within specs you can get away with a ring and hone job which is pretty cheap. If it's out of specs you need a new piston, rings, and a bore/hone. You can either go stock oversize, wiseco oversize, or a big bore kit. If you want it to stay pretty much stock I would get the wiseco oversizes as they bump up the compression some adding more power for the same cost as stock. Just go .020 over the .080 isn't worth the gain along with not having any more overbores left in the sleeve.

[2muchquad]

i recently bought a 300ex beater,the motor would not rev out,upon dissaembly i noticed the rockers were badly worn,BUT i also notice one of the cam lobes was almost completely worn.it didnt have the lobe on the exhaust side.you never know what your gonna get when you buy a used bike...