The R69s dynamic balancer

[malmac]

Well folks I have an R69s and it has no dynamic balancer fitted.

Anyone out there have one fitted and able to give me some information re the parts.

The reason I ask is that I feel sure some of the parts I could turn up on my lathe if I knew the dimensions.
Some parts I would have to buy but making several of the parts might well half the overall cost.


Thanks in advance.


Mal

[schrader7032]

The elastomeric parts are known to fail over time, resulting in a wobbling mess under the cover. The balancer is really only needed for bikes that are run near redline for a long period of time...basically a race bike. Recently, I completely removed the balancer on my R69S. There is no noticeable effect of the loss of the balancer that I can tell.

[Slash2]

Hey Kurt. I’m curious why would BMW have designed the balancer if it was somewhat superfluous? I’ve heard of plenty of bikes running fine without them but it just seems odd.

Mal, I think I have the individual pieces you need to make your own. I’m no whiz with a caliper but I could probably give you what you need. The elastomers are available inexpensively through Salis.

[wa1nca]

I was informed by Richard from Benchmark that if I wasnt going to race my r69s then it was not needed
You can shorten the generator bolt or add a spacer to it so to hold the generator on the crankshaft

Tommy

[schrader7032]

It was because of the bearing support design for the R69S, the higher horsepower, and racing the bike. The crankshaft was observed to flex in certain situations, hence the balancer. But Tommy's right, I've read many places by other people that the balancer isn't needed for the average Joe. Duane Ausherman has long advocated for getting rid of it.

I think I just put the original bolt back in and just took out #4, 5, and 6 and put the rest back in.

https://www.realoem.com/bmw/enUS/showpa ... Id=11_2755

[malmac]

Thank you for offering to give me dimensions.
While I wont take up that offer at present, I would still be interested in what the parts are manufactured from.
I have seen the front bit that seems to be made of aluminium, but the large central bit, is that made from steel?

The general concensus seems to be, not needed unless the engine is to be taken to trak days and run at very high revs.
I am not the race bike type, and really if I want to fast I'll take the 1200.
Not putting a hot camshaft back in so I think I will not bother about a balancer at this point in time.


Thanks


Mal

[wa1nca]

The original generator bolt M8X60mm
generator bolt with damper is M8X70mm with a shoulder as shown
I added a 10mm spacer and used the M8X70

https://bmwclassicmotorcycles.com/index ... 1230070145

Tommy

[malmac]

I figure it is something I can retro fit.

Will see how the engine runs after the rebuild and make a decision as to if it is necessary.



Mal

[miller6997]

My present R69S has 80,000 miles and the balancer was removed by my brother, a BMW tech at the time, when the bike was new. I've never known anyone who did not take it off. The original rubber donuts wore out quickly and caused a hellacious wobble. I never get rid of anything, so I may still have at least one, maybe two, of the assemblies. If you decide to install the &%*$ thing, PM me and we can discuss it (but don't blame me when you take it off and put it in the recycle bin).

[malmac]

The dynamic balancer is not getting a very good review.

But thanks for making the offer but I think it makes sense to pass.


mal
Australia