Drive Shaft Failure . . . . Prevelent problem?

[Redman]

Other posting involves a drive shaft failing. Okay, for the Brits: "the propeller shaft".

(I think I know benifits and disavantage of shaft verse chain, thats not what I am asking.)

How prevelent is this problem of shafts/couplings/splines failing?

SOme have said its a common problem, and thats why they dont like shafts. I have had one shaft with 60 thous+ and another for about 40 thous with no problem. I change lube at least every other season.
Anybody have any comment about what it takes, how much abuse, to cause a shaft to fail on a stock bike?

(Without starting another shaft verse chain argument.)

[daveo]

I usually hear about the driven splines on the wheel failing, due to lack of lube. Shaft drives can most likely be fully inspected by a bearing check and measuring both the pinions backlash to determine wear, if feasible...I have seen some shaft drive BMW GSs break the swing arm, albeit off-road. Suzi GS ones seem pretty good, I've only had the 650, for a short while, but no problems. Judging from horsepower available, I bet you could beat them as long as it holds gear lube. The rubber parts are the weak spot.. IMO

[jimcor]

All the spline failure stories I hear are caused by lack of lube. Just grease them babies up when you do a tire change and you should be OK. Horror stories I've heard mostly involve Gold Wings.

[dpep]

I recently stripped splines on my 1100GK (82) . I only bought it last year, and it shows around 30,000. The splines had grease from my most recent tire change, but I do not know the servicing in its previous lives. I believe Nick was saying there was a different metal used for the splines in the later shafties, a softer metal. They are more prone to strip. I believe that started in '82. Nick may chime in here with that detail.

That would be consistent with my experience. I have a 1980 850 that kept it's original hub and splines through 100,000 miles.

[Redman]

Oh, .... You guys are talking about the splines on the wheel (between wheel and rear drive unit) failing, not so much the splines on the shaft and coupling. OK. OK, I am with ya now.
Yah, I have seen that when removing the wheel to have tire changed. I smeared the splines with axel grease. It is outside of the gear drive unit and doesnt get lubed with the gear oil.

Thanks Daveo, Jim, dpep.

I have heard of similar problems with my buddys 83 Old Wing of things wearing out in the rear wheel (bearings, bearing mounting openings, splines). Service manager said that in early 80s the tires had to be changed more often than more recent tires, so that stuff in rear wheel got lubed more often than it does now with tires that last longer. Seems like same situation here with the GS shafties.

So sounds like the problem is worse if someone changes the tire but doesnt lube the wheel splines, so you get lot of miles without regreasing the spline.

[focus frenzy]

thats correct Don, they went to a differant grade of aluminum in 82 and if you don't grease the mating plines for the wheel it will eat the splines at the wheel.
I have never heard of a drive shaft failure, I know only of the hub issue, and cleaning and re-greasing of the splines take care of that.
I have also heard of a couple 650's breaking the output shaft where it comes out of the transmission but this is pretty rare and may be limited to a manufacturing error with a batch of the output gear shaft.

I have about 140K miles on my 80 1000G and other than a output seal failing at around 130K miles, I have never had any problems.

[bwringer]

Yup, the earlier wheel couplings are made of a darker, harder metal.

The wheel splines on my '83 went blooey at about 56,000 miles, and I scored a flawless set of low-milage early model splines from a seller on eBay. A few days later, I won the auction for the drive unit that went with the splines. When the parts arrived, I was amazed that they showed no visible wear at all, so I installed my new goodies as a set. I also grabbed an entire rear wheel cheap so I would have a backup spline plan.

The splines in my original drive hub were OK, but there was some visible wear. I imagine that the wheel splines are meant to be the sacrificial part, since they're so much easier and cheaper to replace.

I had always greased the splines faithfully, but I didn't know to use a moly grease instead of regular grease. Maybe that had something to do with the failure, maybe not.

A brand-new spline unit is only about $100 from Ron Ayers, so if you can't find anything on eBay, that's a reasonable option. It has a superceded part number, so maybe it's been revised to be a little harder than the original softies on the later G models -- who knows?

Here's a bad scan from my GS850GD microfiche:

http://bwringer.com/gs/images/rear_wheel.gif

The part number is 64680-45112, and it's #14 on the diagram. When you punch it in a http://ronayers.com , it comes up as a superceded part, with part number 64680-45113 for $99.83.

[mcconnell]

I personaly know of 3 output shaft failures on 1983 1100G's; mine, my brother-in-laws, and the one in the salvage yard I tried to get parts off of. I ended up putting on an output shaft assembly off of a GS1000.

[saaz]

I rently bought a 96 ST1100 Honda (as well as the GS!!). Lubing the splines is very important. Using the right grease is also important. The Honda moly paste is the best bet, with at least 40% moly (moly grease only has 3% or so). There are other brands of moly paste around, and also synthetic substitutes. Make sure it is for drive splines.

[bwringer]

To answer the original question, it seems to be something that happens once in the life of every shaftie, unless every single owner has been religious about maintaining the correct type of grease on the splines.

With that said, it's certainly not a catastrophic failure, and is fairly easy and relatively cheap to fix. Everything else in the shaft drive system used on GSs has proven to be bulletproof.

The biggest plus is that even if you have to spend $100 on a new spline unit at some point, you're still WAY ahead of the chain-driven primitives. A new o-ring chain and sprockets will set you back $150 to $200, and MUST be replaced every so often. If you're a real chain care fanatic, you might eke out 20 to 30,000 miles from a new chain and sprocket set. And then there's all the work and mess of regular cleaning, lubing, etc.

All a shaft drive system needs is a gear oil change once or twice a year and moly grease on the splines whenever the rear tire comes off.

A broken chain can fail in a few rather catastrophic ways, such as wadding up near the countershaft and tearing a hole in the engine, or wadding up around the rear hub and locking the rear tire suddenly at speed. When the splines let go, you just get no drive power suddenly.

I prefer shaft drive, but I have to admit all those parts are bloody heavy. Plus, you can't change gearing, which I would love to do on my 850G.

There are trade-offs to both systems, obviously. Take your pick!

[Redman]

Ah, okay, Moly lube, not reqular axel grease.
Will I find that at discount auto store (Auto Zone ectera) or is it particular to motorcycle dealers? Any particular specifications, weight, percent moly ectera? Paste, 40%?

[I am again amazed at the knolodge and helpfullnes of you various GSR members. Whooo, knowing what year the metalurgy of a certain internal part changed, WOW!]

[saaz]

Try this link as it is from the US and says where you get various things from. A good link for other info as well! The paste is 60% moly, but I have seen reference to 40% in the Haynes manual. All these will last years as you don't use very much. Specialist bearing places may also have it.

http://motorcycleinfo.calsci.com/Consumables.html#Splines

I also using synthetic in the rear gear casing, only 150mls so I won't go broke! My experince with using it in the car as well is that it does last a lot better than mineral based oils. There is no separate gear oil on the front for the ST.

[Poot]

I just dissasemnbled my back end, and had greased it with a green, wheel and bearing grease. I will definitely get the moly!

Another thing , happened when I change the gear oils. I changed the rear - secondary gear oil (which was still only slightly darker than the new oil, and clear) . When I went to change the front secondary-gear oil, it was thick, black-brown , and foul-smelling....


Thanks also for the moly tip!

[pidgey]

Probably not changed by a previous owner due to the hassle involved !
Those phillips bolts are a ba**ard, eh ? Even with an impact driver, they were tough to get out.

[bwringer]

You can find moly bearing grease at any auto shop (it's usually black rather than the usual translucent brownish), which is far better than nothing or regular grease.

The Way of True GS Righteousness would be to use the thicker pasty goop intended specifically for shaft drive bikes.