Put fresh cylinders on, and new cam, cleaned up everything. bike ran before this. The only thing i can think is a not perfect valve adjustment and when the pistons were going in the cylinders the ring compressor (was on as tight as i could get it) felt like a ring snagged for a second going in the cylinder. Right now the motor turns halfway untill one piston is at the top of its cylinder, like a valve is hitting it. i look in the plug holes and no open valves in that cylinder and the pushrods all turn easily when engine comes to a stop. (I am rotating tire in 5th gear, and would think the valve hitting a piston would make it hard to turn a pushrod) the pistons seem to be traveling smoothly when their moving, and i was super careful on the pushrod adjustment, 4 turns from zero lash off cam lobe. my 3 thoughts were something in the cam area (oil pump gears), something with ring catching, valve hitting (ill definately need a valve or 2 if that happened) would i be able to see the culprit valve if piston hit it and bent it out of sight. Also i was super careful to drop nothing in open case (kept it covered) thanks in advance for any ideas before i pull engine apart again
SINCE ORIGINALLY POSTED I COLAPSED THE PUSHRODS SO THE PISTONS CANNOT BE HITTING A VALVE. IS THE WISECO PISTONS #4724P3 (30 over) ABLE TO BOTTOM OUT ON THE BOTTOM OF THE PISTON AREA? I WILL CHECK CAM AREA AND PULL PRIMARY OUTER COVER IN THE MORNING SEE IF SOMETHING IS HITTING/STUCK/MIS-ALLIGNED SOMEWHERE

 

Hello and welcome to the forum. Lots of guys in EvoLand that could help as well..

What cam did you put in it? Some cams need to have the case clearance to be able to rotate fully... You will need to relieve the pushrods, remove lifters and blocks and then make sure the inner most cam lobe is not hitting the case.

 

When the piston stops is the valve open?
Just look dwn the port and see.
If it did hit it is bent.
It takes almost nothing to bend a valve .

 

if the pistons are domed,you have them in backwards.

 

Never use the tire to turn over an engine to check for valve clearance - you will bend a valve if it hits. If you have a complete hard stop, it sounds like the piston may be hitting the head - assuming you valves are not seriously bent and cannot close. It most likely does it turning the engine in reverse direction as well. Good advice on possibility of piston in backwards.

 

Yea right I always use a socket on the crank to spin the motor over... Don't trust anything else...

 

with the wiseco domed evo pistons,they have to go in with the right orientation to the D shape chamber,seen a lot put in backwards.100% sure this is the problem,not a valve hitting

 

Yes - I agree. That is why I said it most likely does it the other direction. I wanted to point out about never using the transmission to turn the engine - people do not realize the torque multiplication makes it nearly impossible to not damage something that will hit.

I have seen many pistons hitting heads.

 

Pistons are in the wrong cylinder.
Scott

 

This is not to diss on you but just ascribed logic-
If you got the slugs in the wrong holes, I would personally interrogate myself on the rest of the job...
New cam bearing?
Check your valves, seats, and guides?
Lifters?
your squish?
obviously not.
Rings measured?
in the proper side up?
measure rod lateral?
I am worried about you slam dunk.
just trying to help..no dis