R80G/S Ring Gear/Flywheel

billmendenhall · 03-10-2010, 07:37 AM

On a recent trip to Baja on my 1984 R80 G/S, I had the ring gear separate from my flywheel. Not a nice thing to happen in the middle of nowhere. It looked like the ring gear was riveted onto the flywheel and it is our assumption the rivets failed. But, since we were only looking at the ring gear through the small opening where the starter gear engages the flywheel, we really were not sure. Fortunately, we were able to creatively repair it with some side stand extension screws.

Our temporary fix worked very well. But it left me wondering, has anyone ever heard of this happen before? Seems strange to me that rivets would fail.

BeemerMarc · 06-09-2011, 10:53 AM

Yes, this just happened to me on my 83R80RT last week. I noticed a weird noise coming from the clutch area driving home from work one day, I didn't want to risk the metal on metal noise so I went ahead and pulled the tranny and clutch pack and noticed that the ring gear was loose. Thankfully the rivets were just loose but did not shear. Now I am pondering how to fix the dang thing? Do I take it to a shop to re-rivet the ring gear back on the flywheel or do I put on a used flywheel, which I have already, and have the assembly rebalanced? Not sure, anyone else have this happen to them?

maalstroom · 06-09-2011, 11:51 AM

I bet they would know in OLD'S COOL.

BeemerMarc · 04-05-2013, 06:29 PM

I ended up putting on another used flywheel and this worked out just fine, runs like a champ now and I didn't end up having to re-balance anything. I used a short dowel in the front cover to rotor area as a spacer to hold the crankshaft perfectly still while removing the old flywheel. It took a few extra minutes to set this up as I didn't want to risk having the crank pushed in by mistake. I also made a short bar with a couple of bolt holes to hold the flywheel from turning while I undid the flywheel bolts. This ended up being a pretty time consuming job overall but I was able to perform some other maintenance along the way so I am pleased with the outcome.

mendoje · 04-06-2013, 08:51 PM

Quote:

Originally Posted by billmendenhall

Our temporary fix worked very well. But it left me wondering, has anyone ever heard of this happen before? Seems strange to me that rivets would fail.

http://www.advrider.com/forums/showthread.php?t=714918

One Less Harley · 04-07-2013, 07:24 AM

happened to mine at one time and was "fixed" with short allen screws (link #1) by the DPO, which eventually got into the starter bendix (link#2). I didn't realize that's what tore it up in the 1st place. It wasn't until I removed the starter to clean it up that I noticed the new bendix having received damage. Took me a little while to figure it out.

It would be best to remove that flywheel ASAP.

SOLO LOBO · 04-07-2013, 07:25 AM

Somewhere out there I read an article/post that the earlier G/S has a fragile clutch carrier that was prone to failure.... You can see the marks where it happened to my early '81 G/S

AirheadGS · 04-07-2013, 04:34 PM

I had that happen on my G/S 20k miles ago and not having enough sense at the time to get a used fly wheel went and TIG welded it together with 316 SS rod and have not had any problems. I have checked the welds for cracks so who knows I may have gotten lucky.

06-09-2011, 11:51 AM	#3
maalstroom Ferret Legger Joined: Dec 2006 Location: Laguna Madre Oddometer: 455	I bet they would know in OLD'S COOL. __________________ ...................... My gears grind more and more each day.

04-07-2013, 07:24 AM	#6
One Less Harley OH.THAT'S GONNA HURT Joined: Nov 2006 Location: Bowling Green, Ky Oddometer: 3,814	happened to mine at one time and was "fixed" with short allen screws (link #1) by the DPO, which eventually got into the starter bendix (link#2). I didn't realize that's what tore it up in the 1st place. It wasn't until I removed the starter to clean it up that I noticed the new bendix having received damage. Took me a little while to figure it out. It would be best to remove that flywheel ASAP. __________________ 2004 BMW R1150RS 1984 BMW R80G/S (wrenching index) 2003 Suzuki DRZ 400S (TAT Prep) One More DRZ does the TAT (Ride Report)

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03-10-2010, 07:37 AM	#1
billmendenhall ^OP n00b Joined: Jul 2007 Oddometer: 3	R80G/S Ring Gear/Flywheel On a recent trip to Baja on my 1984 R80 G/S, I had the ring gear separate from my flywheel. Not a nice thing to happen in the middle of nowhere. It looked like the ring gear was riveted onto the flywheel and it is our assumption the rivets failed. But, since we were only looking at the ring gear through the small opening where the starter gear engages the flywheel, we really were not sure. Fortunately, we were able to creatively repair it with some side stand extension screws. Our temporary fix worked very well. But it left me wondering, has anyone ever heard of this happen before? Seems strange to me that rivets would fail.

06-09-2011, 10:53 AM	#2
BeemerMarc n00b Joined: Nov 2010 Location: So Cal Oddometer: 3	Flywheel Ring Gear Yes, this just happened to me on my 83R80RT last week. I noticed a weird noise coming from the clutch area driving home from work one day, I didn't want to risk the metal on metal noise so I went ahead and pulled the tranny and clutch pack and noticed that the ring gear was loose. Thankfully the rivets were just loose but did not shear. Now I am pondering how to fix the dang thing? Do I take it to a shop to re-rivet the ring gear back on the flywheel or do I put on a used flywheel, which I have already, and have the assembly rebalanced? Not sure, anyone else have this happen to them?

04-05-2013, 06:29 PM	#4
BeemerMarc n00b Joined: Nov 2010 Location: So Cal Oddometer: 3	I ended up putting on another used flywheel and this worked out just fine, runs like a champ now and I didn't end up having to re-balance anything. I used a short dowel in the front cover to rotor area as a spacer to hold the crankshaft perfectly still while removing the old flywheel. It took a few extra minutes to set this up as I didn't want to risk having the crank pushed in by mistake. I also made a short bar with a couple of bolt holes to hold the flywheel from turning while I undid the flywheel bolts. This ended up being a pretty time consuming job overall but I was able to perform some other maintenance along the way so I am pleased with the outcome.

04-07-2013, 04:34 PM	#8
AirheadGS lost in suburbia Joined: Jun 2004 Location: Lakewood,CO USA Oddometer: 9	I had that happen on my G/S 20k miles ago and not having enough sense at the time to get a used fly wheel went and TIG welded it together with 316 SS rod and have not had any problems. I have checked the welds for cracks so who knows I may have gotten lucky.