Safety Webcamnude R C 0 WWW SE580 COM 1 De Userlogout Asp Webcam Installed the manual cam chain tensioner from APE - K-Bikes.com - Excellence in Motion

  #8  

Jun 19th, 2011, 10:35 pm

Wow! Shot a bunch of photos and sketches via email to them this afternoon and I find the APE Racing guys are working on this - and on a Sunday evening?

Anyway, they are turning the design over to their machinist Ben for a rework of the body or something to cover and seal that oil galley hole. They said the same thing occurred on the Yamaha R6 design so they are aware of it.

I thought just a thin sleeve would do the trick, but the hole extends down into the piston body as well so oil can get in there and go around the threads on their tensioner and you have less oil pressure as a result. You can see part of the cut on the very far left inside the bore in this photo:



Now we wait a bit. I may fab up something myself in the meantime.

Aside, I'm sort of amazed the little Canon G9 P&S camera can take such sweet closeup photos.


Mack

  #9  

Jun 20th, 2011, 4:46 pm

You're doing a better job of this than BMW!
Thanks, and keep posting. I'll be saving my pennies for when production part goes on sale!
Tom

  #10  

Jun 20th, 2011, 5:36 pm

Thanks Tom.

I tore into again this morning and I think I figured out a way to stop the "oil galley free-flow" escapade. I did an overlay of what I suspect will work and seal off the oil galley on their flange as they supplied me on the beta version. I just sent this to them a few minutes ago. We'll see...



The red area in the diagram/photo is where the oil flows around the thread and into the engine and I suspect where I was losing oil pressure at idle. With the long BMW hydraulic piston in there, that cannot happen easily.

I'm still wondering why BMW allowed so much compression on their piston that could account for the skipped-chain event. The way it is designed, if ANY particle gets into the small check valve ball that is inside the piston, then it could easily compress and the guard will kick back and the chain skip will occur (and your engine is toast). When I took it off this AM, there was debris around the lip of the oil galley (I took a photo of it too as I didn't believe it when I saw it.). Trust me, your filter ain't getting all the crap floating around in there. If that crap had gotten into the check-ball seat of the piston, then I could see it compressing and maybe a chain jump occurring. In some posts on this forum, the BMW mandate mentions "Pumping up that piston with oil until it no longer compresses." Wonder how may actually do that?

On the Gen. I models that had the spring, the piston may have not been able to compress fully. With the Gen II with the hydraulic cylinder, who knows? Someone mentioned they thought the later models (Gen. II tensioners) were cratering more engines. Maybe the piston less that spring allows that? I dunno.

Anyway, I'm awaiting APE's ideas since the photo overlay was sent.


Mack