sprocket question

[spike55_bmw]

You may remember that late last year I had a transmission problem at 20K miles and needed to open up the whole engine to mess with the shifting drum. It turned into an interesting journey and another "learning experience" (sort of getting tied of that sort of `learning' but it is usually my fault). I mistakenly took someone's advice to ball-hone the OEM cylinder bore and throw a new set of rings (standard bore). I just posted a picture which shows that all of the ring end-gaps migrated to a 90 deg arc on the right side of the cylinder by 27K miles on the clock. You can also see that there was a tremendous amount of blow-by / oil burning as a result. My advice to anyone pulling the cylinder always re-bore and starts off with fresh surfaces (cylinder / rings). The only additional cost is the machine shop, which was less than 33% of the total cost of $350 (me doing the wrenching). Kawi can supply 0.5 mm and 1.0 mm piston / rings. Please note that all rings from Kawi are now the post-09 design (no pre-08s available) and a new design piston is required. There was a minor hiccup with the machine shop. It's an older operation and their mill was set to 0.02 inches not 0.5 mm (= 0.0197 inches) to bore the cylinder. This resulted in making the new ring end-gaps, in the new bore, to fall more in the middle of the spec range versus on the tight end but all was OK. So, this past Thursday I started into the break-in procedure: no idling, 3,500 rpms, on / off the throttle for 20 miles, turn off and let it cool down and do it again. At 50 miles, up to 4,500 on / off the throttle. I changed the oil / filter at that point too. After 100 miles, take it up to 5,500-6,000 rpms, on / off the throttle. At 500 miles, it is either fully broken or broken in. I'm currently up to 300 miles on the process. The engine sounds and pulls well (no smoke & clean rear fender) but the Jet Stream is about make a dip over the East Coast and that will bring back seasonally cold / rainy weather. Further testing will have to be postponed but it was fun while it lasted. Don R100, A6F

[cycletip]

My hats off to you Don. Always admire someone who can dive into a job like that. Especially cases which split down the middle. Good job! What was the trans issue?

[Greg May]

[Tengai Mark Van Horn]

At 2:09 PM +0000 11/14/10, spike55_bmw wrote:

>... the Jet Stream is about make a dip over the East Coast and that >will bring back seasonally cold / rainy weather. Further testing >will have to be postponed but it was fun while it lasted.

Awe... you can do it, especially since you're south of me near the tropics of PA. I'm still riding my Tengai to work every day, rain-or-shine, and will do so this week too! "There's no such thing as bad weather, only bad gear." Mark

[spike55_bmw]

Why not ask the pretty girl to go home with you? You might have to do the job twice, losing a gasket and some time but it's always good to learn something and be a little bit better than what you were yesterday. Start out small and work your way up - incremental progress. Don R100, A6F

--- In DSN_KLR650@yahoogroups.com, "cycletip" wrote: > > My hats off to you Don. Always admire someone who can dive into a job like that. Especially cases which split down the middle. Good job! What was the trans issue? >