gs850 shaft drive

[Scudder]

I've never ridden a shaft drive. I have acquired a gs850L. I'm used to chain drive. When I have my chain drive bike on the center stand the back wheel will rotate easily when I spin it by hand, when in neutral of course. My shaft drive doesn't. It seems logical to me that I wouldn't, but I'm wondering if some of you shaft drive guys could give me an idea of how much spin a shaft drive rear wheel will have, in neutral, when it's on it's center stand.

Thanks,
Scudder

[850 Combat]

They turn pretty freely when in nuetral. There is more friction than with a chain, due to the two sets of bevel gears , U Joint, etc., but not that much. When you say "spin" Are you asking how long it will spin on inertia if you grab the tire and spin it? I never do that, but I'll say that it would be somewhere between not long and not at all. I often turn the wheel for cleaning, and it is also how I turn the motor for valve adjustments. If yours won't turn, there is an issue. My first suspicion would be that it isn't in nuetral. I'm assuming that it doesn't run, and you have not turned over the motor.
When you are rolling a G about, it really doesn't feel much different than an E

[Scudder]

The bike runs (just recently) and I have ridden it a small amount. I've changed secondary and final drive fluids. Everything is pretty much in order, as much as possible at this point. Just wondering if the rear wheel when in neutral should rotate like a chain drive, and if not, how much of a rotation should a normal shafty get. I don't get a full rotation from the shaft drive and I do out of my chain drive gs750.

Scudder

[Redman]

I would not expect more than a full rotation, actaully less than a full turn and that is spining it hard.

But, anyway, try prying aprt the brake pads, see if that makes a difference.

.

[Tim Tom]

I've never been able to spin my back tire 'freely.' I think this may be due to the increased friction and mass of the drive chain. I don't think this is out of the ordinary on most G bikes.

[7981GS]

Try it after you have ridden 40-50 miles and the Gear oil's have gotten to temperature on a warm day.

Daniel

[BassCliff]

Hi,

No, it will not spin as freely as a chain drive. If it spins at all (1/2 turn, 3/4 turn) you are fine. There is a lot more hardware to turn, even in neutral, when the driveshaft and associated hardware is involved.


Thank you for your indulgence,

BassCliff

[1948man]

My chain driven bandit's rear wheel is real free but my GS shaftie won't spin much at all.

[keman]

Consider how many more parts are moving when you turn the shaftie tire. Many of the parts are either packed in grease, or thick gear oil.

Motor oil in a glass will spin up nice when stirred with a spoon, even turn the spoon several times around the glass if you let go. .. If you try the same with 90w gear oil, you get a real good idea of why the tire does not spin freely.

[Buddy]

Do your chain drive bikes have drum brake? If so there's more "free wheeling" in a drum brake set-up.

Buddy

[Scudder]

Thanks for the replies. Sounds like my shafty is pretty typical of what you all are describing. I appreciate it.

Scudder

[Normk]

You may wish to pry the brake pads back from the rotor and try turning to ensure that it isn't a brake drag issue which is involved.

The effort required to turn a shaft drive isn't much different from a larger chain but even these vary between makes and models. Temperature is more of a factor with shaft drive than chain so if it is cold, the drag will be significantly higher. Depending on the gear oil, you may have quite a drag due to thick oil. Gear oils typically come as SAE 90 or SAE 75W-90 which are significanly different in drag, especially when it is really cold.

Note that the SAE number ranges for gear and motor oils are different so a 90 oil means it is a gear oil and not that it is thicker than a 50 which is an engine oil. A 75 gear oil is thinner than a 50 engine oil. Try pouring some to see the differences or even shake some oil bottles in your local parts store. I recommend using a 75W-90 gear oil if you change the drive lube rather than a 90 as there is lower drag and more effective lubrication.

Just make sure that you buy a hypoid gear oil. Yes, I know the drive is a helical set but hypoid is rated higher, more common and so less likely to obtain an unsuitable lube. IMO, synthetic is OK but not worth more money as the big advantages are at higher and lower temperatures than your bike will encounter.

It may also be useful to compare the drag of other shafties so keep your eye open for opportunities. Most people are happy to talk about their bikes although approaching some young woman on a BMW with the request to see how hard her rear end is to rotate may provide an interesting experience.

Let me know how that works out.

The concern here is that you may have some undetected issue so some quantitative measures will be safer for you to detect such an issue. One rule of thumb is that the bike should idle in gear with clutch out (on center stand of course) at essentially the same RPM as in neutral.

[Normk]

Can't resist a follow-up. One has not ridden a shaft drive until they have ridden an older BMW!

The feeling of popping up and down as throttle is opened and closed is stranger than fiction and really must be experienced. The Japanese have never learned to design motorcycles properly.

They tried to copy the classic Brit twin and produced the Kawasaki W650(?) which was a dismal failure as it failed to capture the essence of classic Brit bikes. It didn't leak oil or flood the carbs.

They have never matched the mistique of German engineering either. One would think that they could make a shaft drive bike which performs as it should by climbing and falling what feels like two feet when the throttle is opened and closed.

How about cruiser V-twins? Also a failure. Don't they understand that the essence of this type of machine is that it must be unreliable, low powered, run like an old John Deer tractor with no muffler, bad carb. and a loose distributor shaft? Who would want to dress up like the cast of Mad Max and ride a quiet, reliable, powerful machine? Just silly!

Don't know what we will do with those people!

There, that should have offended nearly everyone excepting the owners of Japanese bikes. And who cares about the others?

Going off to hide now!

[49er]

It's very difficult to find shaftie members of the "Japanese axle jacker's club". The closest I have found was a member of the "GSX chain whippers club".

I rode a GSX750 recently that had a chain that loose that it exhibited jacking tendencies, that were quite pronounced on and off decel.

[Normk]

No recent posts on the subject so will risk a slight hi-jack.

Just pulled Suzie's rear wheel to replace wheel bearings and noticed that she has the original rear wheel drive plate having the pins retained by nuts.

Anyone know if this recall is still in effect?

The young lady in service at our local Suzie dealer was laughing when I asked her to check. This is the most fun I've had in several days and it will be even funnier if the bike gets to go in to have the hub replaced. She is older than the guy who will do the work.....and most of the saff.

Don't get on my case over this, I'm retired, just because you have a life with real events of importance it doesn't mean that all of us do.