Kz305 interference engine?

Anyone know the answer to this?
After rebuilding the top end of my engine, waiting almost a month for a new starter I finally had the chance to try and start it with no luck. I turned it over multiple times before I checked possible causes.
I found the timing out 90°. Not sure why I installed the cam like this but I re did it and I know for sure its good now.

I just need to reinstall the cover and all the other bits before I can start it but I'm really hoping I didn't hit the valves with the timing out.

The 305 are pretty much 1/2 a gpz550, very similar in a lot of respects.

Assuming you turned it over by hand carefully several times, with the camchain under tension before cranking on the starter I think you will be ok. Even if you did feel interference, as long as you are gently turning and stopped at the slightest feel then I think you'll be ok.

Like I said. I felt something but it wasn't much. Hopefully ill find out tonight after work.

AS long as you know it's right, turn it over with the plugs out and see if you have compression. Hopefully you didn't nick the valves but if you did, you know what's next.
Steve

i burn it to the ground because ill never find the parts. :laugh:

i'll remove the plugs and check compression. i assumed compression was find since i can see the carbs moving in and out when its cranking over.

90 degrees off... retarded or advanced?
The good news is that with a single cam, it doesn't matter, the actual valves can't hit each other.
The bad news is that there is a very good chance the exhaust valve has hit a piston tough because the piston is rising towards the valve in the exhaust stroke.
If you made the mistake retarding the cam timing, you might have dodged a BIG bullet.
Not quite as likely to hit the piston with the intake because the piston is moving away from the valve when opening... 90 degrees though, ugh I hope it was late opening.....

it was advanced......

These valves aren't made of putty, exhaust valves are one of the most highly stressed components on the bike. The importance of valve clearance here isn't so much about keeping the cams happy, it just gives the exhaust valve a few fractions of a millisecond more cooling time when the valve shuts and heat sinks into the cylinder head.

If you were a 25 stone nightclub bouncer using a 1 metre breaking bar to turn the crank you hoping you can force it to turn then they'll bend, if you were gentle and stopped at the slightest feel I really think you'll be ok here.

This is based on my experience of goofing up a few times over the years -gently. Either I got lucky and I'm wrong, or you'll be ok.

Most bent valves occur when the motor is running really fast, well into the redline and the valve springs can't shut them fast enough . If in doubt get that compression tester out. I really think you'll be ok on this.

The immense forces on that motor are almost beyond belief: the acceleration of a piston from TDC down a bore is as quick as a rifle bullet from breech to muzzle !!! 25 years later and I'm still amazed by these machines.

If you don't have a compression gauge, put your thumb over the spark plug hole, turn it over and see if you can hold it without it being pushed off. If you can hold it, bent valves , if you can't, RIDE THE PISS OUT OF IT. :woohoo:
Steve

Got it all back together. Sounds good cranking. I've got compression, but now I have a fuel problem.

Carbs worked fine last year. I did take them apart to change the leaking o rings for the fuel delivery pipe. Can't see what I did causing problems. I can crank it over a bunch of times and the plugs are bone dry and I can't smell fuel.
I opened the drains for the bowls and fuel came out. I'm assuming that means the gas is at least filling them.
I hate removing the carbs.

This time get yourself some Allen screws for the bowels. Makes it a lot easier to work on. Check your jets, particularly the pilots. Send a guitar string through them or a strand from a wire brush. Spray with carb cleaner through all passages except where the diaphragm is If you have them. Eats rubber.
Steve

aaah, but i rebuilt the carbs last year. replaced the diaphragms too.
i had a hard time getting all the seals back in because they all shrank, so if i do take them apart again im gonna have to purchase seals.

the carbs spent all winter with no gas in them sitting on the bench in the garage. i checked them to make sure the slides worked and there were no blockages before installing.