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Well, it happened...

8K views 56 replies 16 participants last post by  blazblu82 
#1 ·
My drive shaft broke and not at home either. No signs or warnings. Stopped at a light to turn left, let out the clutch and gave a little gas, and grind grind grind. Couldn't get it to go period. Ended up having to push the 2+ miles on a hilly road to get it home. Once I got to a safe spot, I turned it on and put it in gear and could feel the entine length of the driveshaft area vibrate right down to the axel hub.

So, this means my bike will be laid up at the shop getting fixed under warranty. So much for progress.
 
#3 ·
Yeah, and my riding season was just shot down. Who knows how long it'll be before I get to ride again.

At least I know what's worse than the bike breaking. Pushing a broken bike up a hill for half a mile or so.
 
#5 ·
I had the bike financed and the extended warranty was a requirement. It's really good coverage, too. No deductible, no hassle. They will even pay to get the bike hauled to the shop when the time comes.

Last bit of work involved the balancer dampners. Would have cost me over $1100 out of pocket. However, with the warranty, I only paid $86 out of pocket. Basically the cost of parts if I did it myself.

When I get some time, I'm gonna crack open the rear-end and see what is grinding. It sounds like it's coming from front bezel area, but it vibrates the whole shaft. Additionally, I can shift thru all the gears sitting still.

It's just odd that it happened while I was making a left hand turn. Like I said, there were not any signs or symptoms of it failing.

Oh well. One less thing to break later. Now if only the stator would die...
 
#10 ·
So, what do all think is the most likely to have broken: 1. Coupler 2. Gear in rrat hub 3. Front bezel gear 4. Shaft itself.

At this point, it makes no attempt to grab anything. It just free spins with a nice grinding noise.
 
#11 ·
That sucks

That would be my nightmare, after redoing the driveshaft thing on mine. I agree don't be taking things apart, but that said, pop the rubber boot of the back of the trans and spin the rear wheel and see what the U-joint does, if any thing, or have it picked up and have a beer. :beerchug:
 
#12 ·
That would be my nightmare, after redoing the driveshaft thing on mine. I agree don't be taking things apart, but that said, pop the rubber boot of the back of the trans and spin the rear wheel and see what the U-joint does, if any thing, or have it picked up and have a beer. :beerchug:
I can already tell you it wont do anything. I can put the bike in any gear and the shaft will spin, but not grab the splines.

I wonder why it failed all of a sudden? Like I keep saying, there not sby symptoms of pending failure. I just stopped and made a left hand turn and it started grinding.

I'd like to get there anyways. I don't want to wait 4 weeks down the road to find out. I'll take a short video and let you hear it.
 
#13 ·
Supposed to be a single clip; however, I ended up stopping the video inadvertently while trying to shift gears and hold the camera.

Clip 1: http://youtu.be/RkazE4bECgs

CLip 2: http://youtu.be/vE7ZDcOiny0

The whole time I was spinning the tire, not only was it making clunking noises, but there was a spring noise of some sort as well. I got the dust boot back just enough to see the shaft. If in neutral, the whole thing spins with no noise. Once I put it in gear, it get clunky and has the odd spring noise to it. I also discovered the rear brakes were adjusted too tight.

Anyhoot, have a listen and let me know what you think.
 
#16 ·
I am really leaning towards failed coupler. For one, the coupler is spring loaded which is what i hear; and two, the shaft spins in neutral which means the hub splines are still meshed. I gotta get in there now. If the coupler is the only thing I need to replace, then I can do that and not wait a month and a half for the shop to take the bike in.
 
#17 ·
Are you able to run your hand along the driveshaft housing while turning wheel to see if you can better isolate where noise is originating? Use the old long screwdriver to the ear trick?

I am leaning toward the coupler.
 
#18 ·
sounds to me like the front spline coupling failed.
Did you ever do the spline lube?

If not properly maintained, the splines wear until it just loses grip...no warning...just skips the teeth and rounds off...then you have nothing to grab onto so it just spins.

Imagine rounding off a bolt head while tightening it...no warning...just skips and then spins....same principal.
 
#21 ·
Damn sorry to hear that. My best guess from here is either the splines on the rear of the shaft or the splined into at the rear end. If you have a warranty though, I would recommend you best not mess with it in case they try to deny your warranty claim. Cause either way you will find out soon enough.
 
#22 ·
Damn sorry to hear that. My best guess from here is either the splines on the rear of the shaft or the splined portion in the rear end gear stripped out. I have seen it happen with no warning on similar designs. One day you stop and then when you try going again at first there is a little grinding then just a vibration from a rotating mass. If you have a warranty though, I would recommend you best not mess with it in case they try to deny your warranty claim. Cause either way you will find out soon enough.
 
#23 ·
So in 1,200+ posts you never did the spline lube that we tell every single member here? If it is the coupler than the splines are going to be shot, you could bet on that. If it's a maintenance issue that was negleted then you might have to pay out of pocket on this one. Hope not for your sake, Good luck...
 
#27 · (Edited)
Got to looking at the ring gear from final drive oil filler area and they look good to me. Snapped a couple pics for your viewing pleasure. How does it compare to a new unit? I wish there was a way to look at the other gear in there w/o having to take the cover off. Final drive oil should have been replaced last summer with the wheel change. Oh, I got to look under the u-joint boot. Lot of reddish crap in there. How much free-play should I see at that end of the shaft?



 
#28 ·
The ring gear looks good in the pic, you can spin the wheel to see the rest of it, but I don't see any problems in the pic.

The shaft should move some fore/aft, riding on the splines, but have no rotational play on the splines. The dust may mean severe wear. I'm still guessing you lost the splines at one end or the other of the shaft.

It's real easy to drop the rear off, can't get the shaft out that way, but you can see the rear shaft splines and try to rotate the shaft in gear and see if the front slips.

Ebay has a lot of shafts, didn't look for a low price but one was priced at $36.
 
#29 ·
I have spun the wheel in gear and the front holds while all the racket comes from the rear. Although, there appears to be some free-play in the front bezel. Uncertain how much is too much. If in neutral, the whole shaft spins w/o an issue. I'd like to take the rear hub off and get a visual.
 
#31 ·
I got it mostly apart now. Wasn't too hard to get the pieces separated. However, I cannot get the final drive unhooked from the drive shaft. I have already done pulled the shaft out of front hub. The inner ring and the mating side of final drive to the ring are both greased.

What's the trick to getting the final drive off? I've tried prying a bit with a crowbar and still can't get it off. Thanks.
 
#33 ·
I have tried various methods to pull the final drive off and the coupler will not let go. I can get a slight wobble out of it, but it refuses to part with the final drive. My guess is the splines are on top of each other. Which means, the final drive splines are shot.

If only I could seize up the final for a moment while the shaft is spinning, I might be able to separate the 2. Otherwise, I'm gonna put it all back together for now.

On a positive note, I appear to have plenty of brake pad left for the rear!
 
#35 · (Edited)
Does it slide back at all? If it moves you might try pushing forward, then jerk toward the back to try and break it free. Like a slide hammer action, the u-joint will stop against the housing, the steel tube where the shaft is. Don't push it off the stand.

Or, try to rotate the wheel backward while holding the u-joint from turning, this might slip the splines back.

PS - There's a post where one failed just as the guy took off, or maybe hit 2nd gear, but he said it just went bang, with no warning. Posted a couple of month ago.
 
#37 ·
So, anyone have any suggestions on how to unbind a bound coupler connecting shaft to final drive? I thought about spraying some PB Blast in there, I just uncertain if it will penetrate correctly. I've already tried slipping the wheel back on and turning it with bike in gear and it sounded like it slipped, but still couldn't pull the f-drive off. I'm stumped and considering just putting it back together.
 
#38 ·
A suggestion. First figure out which way it normally spins. Then grip it tight (in the middle with some large vice grips and using a hammer pound the vice grips in the oppisite direction in an effort to "unlock" the meshed teeth. Your spline teeth are probably marred untill they actually have hooked together. It doesn't take much of a burr to hook the pieces together. On my impact wrenches someimes the burr can be so slight that you can barely feel it after getting the bit out. I guess the trick would be safely (no damage) hold the final drive to wheel connection steady (large wood faced vice???) while you pound the driveshaft the other way.
 
#39 ·
Thanks for the tip. I did pull it off a few minutes ago. Got a good mate with wheel to final drive and dislodged the splines from coupler. I'll have pics up later, but the coupler is nearly smooth inside.
 
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