R100GS Rear Shock

[Stagehand]

OK-- next question: I do believe my stock shock at 70K miles is finally kaput. It weeped a lot of its juice on the CC trip this summer, and now bounces much like an old Eldorado down the road. Question is: what to replace it with?
I am lately doing a lot more offroad with it, and not merely gravel hard pack. More like single track and bushwhacking... I have heard the Ohlins are good, but mostly for street, they tend to the soft side... I have heard marginal things about Fox, Hagon and Works, and WP... I was beginning to think that replacing with an OEM shock was going to be the cheapest, and probably get the best use, considering it went 70k before death. Any thoughts?

Also-- What is the general opinion about rear suspension settings for difficult offroad? Soft Shock and firm rebound? or vice-versa? or middle the both of them? the stock unit has 3 stiffness settings, and 10 rebound settings. (I'm not sure I'm getting the terms correct) I've tried playing around with them, but on a shot shock, it's hard to tell, because even stiff is soft, at this point.
I commute about 40 miles a day on this machine year round, but would like to be set up for dirt despite the necessity of pavement travel.
I now await your enlightenment. Thanks a lot in advance.

[norton73]

I guess you must have liked the stock shock to stick with it so long. Try this guy to rebuild it and report back. I havn't tryed him for shocks, but he did a good job on my driveshaft;
http://www.brunos.us/shocks.htm

I replaced the shock on mine with a progressive @ 20K. Bike has 60K now, holding up well, works good off & on road. I mainly got it because I got a good deal. I'm gonna try a Works on the wife's R80ST when I get that sorted.

[Stagehand]

i bought the machine two years ago with 40k... never had a paralever before that, so my experience is limited. to this shock.

[NHGS]

Originally Posted by Stagehand

i bought the machine two years ago with 40k... never had a paralever before that, so my experience is limited. to this shock.

I was in the same boat last fall and ride about 60% dirt, 30% street, 10% slab. Stock shock blew out on me at 40K miles and I looked into many replacements, including stock. Although it's a significant amount of cash to part with, I went for the Ohlins with the remote adjustable preload and have been very happy with it. In fact, it changed how I felt about the bike once I had it up and running again. With the Ohlins it only takes a couple of twists on the remote to change the ride height. Rebound adjustment (on the monoshock itself) is also easy to access and adjust.

[Stephen]

The stock shock sucks.

I put a Fox on my old airhead. Adjustable. Worked well. Spring a tad stiff for my buck nekkid 175 lbs. Old ones like I had came with a worthless bushing. Now they use a good heim joint.

If I had it to do over again, I'd probably get Ohlins, although at the time the Ohlins lacked adjustment. I like adjustability. Oh, if I could find a WP, I'd get that. Sure works on the KTM.

Bottom line is anything is better than stock. But you're gonna want to upgrade your forks, now...

[Anorak]

BMW sells a WP shock for the r100gs. It's about 800 bones.

[Rubber Cow]

Ohlins is the best I've found for the R100GS.
My current ride has an Ohlins but I've ridden them with the BMW Performance shock (Werks?) and a Fox. THe Ohlins was far superior and easier to have rebuilt than any of them.
Although you may think that the stock shock was working for you I'd encourage you to explore your feelings after a day on the Ohlins. It's night and day.
I'd also suggest upgrade your forks with a Race Tech Gold Valve so that the front and back are matched. This is a great set up for road and offroad.
Hope this helps.
Cheers,
Jorge

[Gringo]

I've been very happy with my Works w/remote reservoir, got about 20-25K miles on it now. I had the same reaction as NHGS did with his Ohlins when I replaced my stock shock with the Works - completely changed the way I felt about the bike. I'm heavy (230) and the stock shock was always inadequate for me alone on the bike, under any conditions; loaded and with a passenger, forget it - was bottomed out so often I actually ground the left side of my fender off (it was warped inward, apparently from the heat of the exhaust). Just wish I'd upgraded the front end at the same time, I waited about a year to put in the progressive springs up front and that was nearly as radical an improvement as the rear shock (and a helluva lot cheaper!).

Any aftermarket shock will be an improvement. Do it up - you won't regret it.

[NHGS]

Originally Posted by Gringo

Just wish I'd upgraded the front end at the same time, I waited about a year to put in the progressive springs up front and that was nearly as radical an improvement as the rear shock (and a helluva lot cheaper!). Any aftermarket shock will be an improvement. Do it up - you won't regret it.

Agreed. I only waited three months before dropping in the progressive springs.

Stagehand, with each adjustment you make you'll find this bike become more your own - and you'll learn a lot too.

[road2blue]

I read or heard somewhere that these hi-performance aftermarket rear shocks, being stiffer than the stock units, contribute to Final drive failure. Any correlation? I bought my '93 with 15,000 km on the clock, the former owner had a White Power shock on it and offered to include it for an extra $300 which I declined. About 5,000 km after I bought it, the final drive was replaced under warranty (it was spewing oil but never completely failed). So the first 15,000 km the bike ran with a White Power shock, and has run stock ever since. The FD replaced at about 20,000 km and has caused no grief since (I've now got about 90,000 km on the bike). I'm a little leery about these aftermarket shocks.

[NHGS]

Originally Posted by ADVENTUREBIKER11

I read or heard somewhere that these hi-performance aftermarket rear shocks, being stiffer than the stock units, contribute to Final drive failure. Any correlation?

I believe the theory that aftermarket shocks contribute to drive shaft failure (vs spline failure at the rear drive) comes from the thought that aftermarket shocks are generally stiffer than stock and can offer greater ride height which creates a more severe angle and puts additional strain on the u-joint.

At 50K on my '94, I'm paying closer and closer attention to these problem spots. Although I hope not to find out the hard way, I can't help but feel a sense of inevitability for some sort of drive failure.

[Stagehand]

i've read a whole bunch of stats relating to the R100GS drive shaft failure, somewhere around 30% dead by 40K (had mine checked, it was fine 10K ago...) I didnt see anything to correspond aftermarket shocks with failure. I also dont see why it would affect final drive before driveshaft u-joints. My rear differential seems like new, still.
BTW-- I put progressives springs up front first thing, and dropped in 15 weight oil. That was a no-brainer.

Link for driveshaft failure rates:
http://www.roadkill.com/~davet/moto/driveshaftfail.html.

COuld be a bunch of Whooee, but worth the thought.
I checked out Bruno's Also-- he quoted me $240 canadian for the conversion to a rebuildable BMW shock, and $120 for a new spring to match my weight to the shock.
Thanks again for all this info. I dont believe any of that stuff they say about you guys.

[Gringo]

I only think the aftermarket shock can contribute to shaft failure in cases where the shock is jacked up real stiff - if your preload is right for load and conditions, it shouldn't hurt your drivetrain. My stock shock had me too low, which may have contributed to the failure of my shaft bearings at 35K. And everyone talks about the vertical element, but how many have considered horizontal alignment? Think about it, if your motor/tranny/final drive are not perfectly aligned and swingarm bearings perfectly symmetrically spaced, then the U-joints are working to compensate in the horizontal plane even if your preload is perfect. I've seen folks argue that both speed and off-roading can be factors, not sure which I buy. Lots of variables.

I believe stock U-joint bearings will all fail sooner or later - it's a lube issue more than an alignment issue IMHO. From the time you first spin your back wheel, the grease in your shaft joint bearings can only go one way - out - it's never going to be replaced. When mine failed, I found two bone-dry, scorched forward bearings and a nice ring of grease spun off around the inside of the paralever - the problem was very clear. I put in a rebuilt greaseable shaft and it wasn't much more work than lubing the splines. It cost 300 bucks, which I hope was a one-time upgrade and not a regular maintenance expense (as it would be if you get another stock, sealed-bearing shaft). Assuming you can take that $ hit and don't mind getting your hands dirty for a few hours, then the worst aspect of this shaft issue is really just not knowing when it'll happen to you. If it bugs you alot, do a preemptive strike - yank your shaft out whenever you can part with the $ and your ride for a couple weeks, and ship it to one of the guys who rebuilds 'em with grease zerks in the joint bearings.

I just had mine open for the first time in 15K for spline AND bearing lube; it was so nice to be able to hook up a grease gun, squirt fresh grease in and see dirty grease squeeze out. Lots of grease everywhere - peace of mind. Worst part of a spline job by far is the taking it all apart and putting it back together, so it's nice to have two chores to do while you're in there, and ward off all surprises in that part of the bike for awhile longer.