Strange chain flailing noise and loss of power

[trolle]

Hi Melana

Nasty experience! But as you are past it, you can be looking forward to getting a "new" engine. If your mechanic has the time, you should make him check the timer chain for wear. I changed mine including the tensioner at 56000 miles.

If you do that and get your carbs rebalanced you will have an engine that really purrs  [smiley=thumbup.gif]

greetings from a windy and grey north - good riding conditions though

[montmil]

Hey, Rob

I recall my question for you today came up sometime back regarding the bead-blasted gasket surface on your cylinder heads. Was there any issue with head gasket sealing after reassembly? Suppose we'd have heard about it by now but don't recall a definitive answer.

Monte

[Rob Valdez 79 R65]

Hey, Rob

I recall my question for you today came up sometime back regarding the bead-blasted gasket surface on your cylinder heads. Was there any issue with head gasket sealing after reassembly? Suppose we'd have heard about it by now but don't recall a definitive answer.

Monte

I never had such clean-sealing heads as when I got them back from Bob.  I had to write and ask if he had checked them for flatness and done any milling.  He said no.
But no, the basting media (I forget what it was) caused no issue with mine.

[Melena]

Hi Melana

Nasty experience! But as you are past it, you can be looking forward to getting a "new" engine. If your mechanic has the time, you should make him check the timer chain for wear. I changed mine including the tensioner at 56000 miles.

If you do that and get your carbs rebalanced you will have an engine that really purrs  [smiley=thumbup.gif]

Trolle,
Good idea.  I'll ask  him about that.  

Rob,
It's already a done deal.  Michael has a guy here in Santa Rosa that does his work.  And Michael is very picky.  The guy here does a good job.  I'll let you know more as the work progresses.  I'll try to get pictures of the new heads when they come back.

[Bengt_Phorqs]

Melena, now that you know what happened mechanically and have a fix underway, what caused that piston to hole out like it did?  Was there a lack of fuel to that cylinder?  Perhaps an oil passage was blocked?  Do you use an SG rated oil?

[Bob_Roller]

I think the valve head mangled the piston crown, when it broke off .

[Bengt_Phorqs]

Bob, a broken valve then would indicate a flaw in the metallurgy or some form oscillation that caused the metal to fatigue.  Any suggestions how to prevent such a happening?  

[Bob_Roller]

About the only thing I can think of, is to replace the valves .

[Bengt_Phorqs]

Well, I think this article answers my questions.  http://www.aa1car.com/library/ar1192.htm

[Rob Valdez 79 R65]

Good article!

[Melena]

Michael said that the left side overheated.  The right side didn't though.  So, it was some sort of imbalance.  

The bike was not running very smooth and it would die at stop signs.  Also it was having an intermittent starting problem.  It would not turn over at all when I pushed the starter button.  But when I pushed it again it would start.  I couldn't get it to do this for anyone else though.

The day it was doing this I took it over to Michael to take a look and he synched the carbs.  They were way out of synch.  So, I'm thinking that might have been part of what happened.  After he did that the bike ran the smoothest ever since I've had it.  

Otherwise he says it might be another fuel problem.  He won't be able to tell until he gets it back together and gets it running so he can check it out.  

[Rob Valdez 79 R65]

I take it Michael does all of your maintenance work, like valve adjustments?  That way he would have known about any recession going on.

When my original heads were nearing the end of their life, I was on a trip and I pulled into a rest area and the engine just died.
I could start it, and it would keep running at speeds above idle, but that is it.
When I adjusted them at the motel the next morning, the left exhaust valve had negative clearance.

That is when I found out how good Bob Grauer is.

[Ed Miller]

Ouch!  Sorry that happened, Melena.  I hope it doesn't kill you financially, as that's some expensive work and parts.  How long had it been since valve clearances were checked, as your running issues that day sound like a closed up valve?

[Melena]

Rob,  This is the first time Michael has done anything on my bike, besides balancing the carbs that day.  

My friend and I have always done all the work on it since I've had it except for one time.  That was 2 summers ago when I had my foot surgery.  I took it to the local BMW dealer and the only reason I did that was because I had a very nice gift certificate from work.  They don't do older bikes anymore usually, but the owner said he would take care of it as he's the only one there that knows about the Airheads anymore.  Michael had worked for him for awhile, but hasn't for a long time, probably when they decided to stop working on the Airheads.  In fact, he found the carb synchronizer in the trash and took it home and refurbished it.  So, the carbs were not balanced except by ear, I'm sure.  

I have hardly put any miles on it since that time.  No riding in 2008, and hardly any at all in 2009.   Just a bad year for riding, it seems.  So, since there weren't that many miles on it since it had the 30,000 mile tune up, I didn't even think about checking stuff out.  It was running pretty good except for the hard starting on March 17, and then the following weekend.  But after the carbs were balanced it was running really smooth.  

Michael does work on lots of BMW's around here as the dealer has a reputation of being a crumudgeon.  He could have a really nice shop, but he just has this attitude problem, and he doesn't work on Airheads.  Had lots of referrals to Michael, so I know he's okay.  Plus my friend's R100T, that he just got last  year and had the engine seize on him on our way to the Autumn Beemer Bash in Quincy last September (that's another story), has been basically rebuilt by him.  And now it is running really sweet.   He does his best to keep the costs minimal.  

Oops!  running out of characters.    That's all folks!

[ambrose78]

Good to hear it is getting fixed.

When do you get it back for riding?


On a completely unrelated tangent it is interesting to see in the photos of the heads that 'r65 'is cast into them... not to mention yet another bmw symbol. When I first got my R65 and was showing it off to some mates, they were amazed to see the sheer number of times BMW was written and/or the prop symbol used. We ended up counting the number of times bmw was written over it - carbs, dash, tank, tank cap, engine, hand grips, guages, rack, some bolt heads, wheels etc etc...

This now brings the total up to a lot +2.