Seems like you've covered a lot, I can't think of anything else at the moment. I've got a 98 EVO with the heads shaved .060", .030" head gaskets, bored .010" with an EV27 which worked out to 180 CCP (I have no idea what CR that equates to). But I have no issues with my stock starter and 3 year old HD battery. I can crank it over off and on for at least 10 minutes (I had a pinched fuel line).

It sure would be nice if you could figure it out without having to rip the heads off. Compression releases only add to the list of things that can leave you stranded.

 

Crane's Fireball Start Boost Relay (#8-3000). That is what I used to help my starting problem. I have a 90 Evo with SE heads and a EV43 and Crane single fire ignition. Was always a pain to start. Stuck that little "boost relay" and wala, starts like stock. Small little box, maybe 1"x1" and just zipped tied it to the bracket that holds on the coil. I think it costs around $16. It might solve your problem and worth the effort before you rip off your heads. I wouldn't feel comfortable just drilling in to my heads without removing them. You'll never know (can't see) if some shavings dropped into the combustion chamber. Google the relay. Good luck

 

Thanks for the input guys...

Did a "google" on the start boost relay, but I can't see how it will solve my problem. My issue is not the start, I cant get the motor to turn over on a compression stroke. If I can rock it past, the motor will spin freely and start immediately.

Now that the weather is finally getting nice, I don't want any more down time however this issue needs to be resolved

 

Check the continuity and loads on all your new wiring, starter and battery. See if under a load test, the battery or starter takes a dump. If so, then you have narrowed your problem down. Without being hands on with you, it's hard to diagnose. Sounds like either one to me from what you describe.

We've seen new Ultima starters take a dump soon after installation, so it can happen.

 

Good advice from all, but guys, remember - they completely changed the starter, '90.

The starters, from the beginning on the Evo production until '90 is a totally different arrangement than the '90 and later bikes. It's the same motor (basically) as the Shovels used and they will barely turn over a bone stock Evo on the initial compression stroke, especially when warmed up.

Only thing you can do is hit the button, if it stalls, let off and hit it again. That lets the engine roll back off the top of stroke and allows the starter to begin from a position it can acheive a round or more of rotation before it becomes under a heavy load.

 

Well, I finally got the heads back from the machine shop. They placed the ACR's in the top of the head, so you don't even know they are there.

Verdict: No starting problems, motor spins over perfectly now, and starts right up. Just glad that was the fix. Now to get riding!

 

right on Ozzie, glad you got it worked out. Going through all that and figuring out the problem is a pain.