Anyone ever had to replace final drive ?
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rPGoatBoy
Well-known member
Wow, broken pinion shaft. That's a first here I think. How did it fail? Did you put those 44,000 miles on 1/4 or 1/8th of a mile at a time? Dump the clutch repeatedly at 7k from stoplight to stoplight?
Maybe there was a flaw in the forging from the beginning that worked its way into a crack over 44k miles. Can't trust those Gen 1s with their faulty metallurgy
. Or maybe it was dropped on that end of the final drive at one point.
Maybe there was a flaw in the forging from the beginning that worked its way into a crack over 44k miles. Can't trust those Gen 1s with their faulty metallurgy
No, it should just pull out. It is a splined interface and had you not broken the input pinion, it would've separated. Hit it with some WD-40, put it in a vise and give it a tug. If that doesn't work, then perhaps you found the root of your problem. If that joint were seized, that could've caused a misalignment of sorts between the driveshaft and the input pinion, and flexed the pinion to the point where it fatigued and broke. Take some pictures of the driveshaft spline when you get it apart, you'll see it's designed to be able to pivot a bit inside of the female spline.
My semi-edumacated guess...
OP sent his bike in to a dealership be repaired for a leaky final drive forward seal.
Shop monkeys broke the pinion shaft off trying to (incorrectly) disassemble it.
He now has what you see in the pictures.
Now, Mr. OP, tell us... (in the late great Paul Harvey's voice) the rest of the story.
OP sent his bike in to a dealership be repaired for a leaky final drive forward seal.
Shop monkeys broke the pinion shaft off trying to (incorrectly) disassemble it.
He now has what you see in the pictures.
Now, Mr. OP, tell us... (in the late great Paul Harvey's voice) the rest of the story.
... nope ... I pulled the pumpkin off myself .. and didn't notice that it was broken ... driveshaft just simply slid right out of pumpkin nice and easy with gear coupler attached ...
.... dealership didn't even mention that the input was broken
... when they took the pumpkin apart to replace the seals, they noticed excessive wear on the ring gear - and informed me that I needed a new pumpkin ...
Of course they didn't mention it... after they F&%$ed it up and told you you need new a one.
How the hell would they have known the ring to pinion gear interface was screwed up if they never disassembled it?
And how would they disassemble it without removing the drive shaft from the pumpkin?
Conspiracy theorizing? Maybe... but it smells very fishy to me.
How the hell would they have known the ring to pinion gear interface was screwed up if they never disassembled it?
And how would they disassemble it without removing the drive shaft from the pumpkin?
Conspiracy theorizing? Maybe... but it smells very fishy to me.
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The pinion to gear coupling was already broken when i gave it to the dealership (but i didn't realize it yet)
- that would seem to explain the ring gear wear - if the pinion gear was "floating" in the gear coupling.
Maybe I need a new driveshaft and gear coupling?
When i gave them the pumpkin, i had already removed the driveshaft and "attached" gear coupling from it.
When they opened the side of the case, they saw the wear on the damaged ring gear - no conspiracy here.
OK, glad to hear it.
This failure sure is an anomaly...
This failure sure is an anomaly...
No drag racing, no clutch dumping ... just Hard riding ... lane splitting every day or so - "redline" to hard braking, repeat, repeat, repeat for 30 minutes, over about 25,000 miles, occasional 500 mile rides with speeds typically in the 80-130 mph range (on a closed course with a professional rider), and a couple track days too.
The FJR is a great bike, and I can't hold her at fault for wearing out a bit after 44,000 miles with the way I ride.
broken pinion shaft:
https://i1152.photobucket.com/albums/p493/katole/bike%20parts/20140826_074725.jpg[/ IMG]
Damage to ring gear:
https://i1152.photobucket.com/albums/p493/katole/bike%20parts/20140826_074524.jpg[/ IMG]
Wear on driveshaft:
https://i1152.photobucket.com/albums/p493/katole/bike%20parts/20140826_074447-1.jpg[/ IMG]
Seems like there is a little play in the driveshaft to gear coupler (both on the old and new couplers) - is there supposed to be a little play ?
- taking into consideration the broken pinion shaft, should I just go ahead and replace the driveshaft ?
Anybody got a spare "mint" gen 1 driveshaft ?
and what's wrong with my image posts ?
(without the space in "[/ IMG]", it kept telling me that I
"can't post an image with that extension in this community" )
https://i1152.photobucket.com/albums/p493/katole/bike%20parts/20140826_074725.jpg[/ IMG]
Damage to ring gear:
https://i1152.photobucket.com/albums/p493/katole/bike%20parts/20140826_074524.jpg[/ IMG]
Wear on driveshaft:
https://i1152.photobucket.com/albums/p493/katole/bike%20parts/20140826_074447-1.jpg[/ IMG]
Seems like there is a little play in the driveshaft to gear coupler (both on the old and new couplers) - is there supposed to be a little play ?
- taking into consideration the broken pinion shaft, should I just go ahead and replace the driveshaft ?
Anybody got a spare "mint" gen 1 driveshaft ?
and what's wrong with my image posts ?
(without the space in "[/ IMG]", it kept telling me that I
"can't post an image with that extension in this community" )
Last edited by a moderator:
RossKean
Well-known member
Turn "off" the "switch" in the upper left of the reply box. Go to the Photobucket "Links". Click on "IMG" - this will copy the URL. Paste into post. Go to next picture. This works in IE. You can use the forum picture posting tools if you are using Chrome. This reply was done in IE.
rPGoatBoy
Well-known member
From the poorly lit ****** picture you took of the driveshaft splines they looks fine. Did you have any trouble separating the splines? Do you see any corrosion or pitting on the driveshaft splines? Any broken ones? If you have a set of V blocks and a dial indicator, you can check your driveshaft for straightness. Hell, even without the dial indicator you'd be able to see if it were bent by rotating it on a set of V blocks. Also, run your fingernail across the area between the shiny, worn contact patch of the spline and where it looks like it's not shiny. A fingernail is usually good enough for less than 0.001" wear indication, you'll feel it 'catch' running across the two different surfaces.
Gotta ask about your failure mode as I would imagine that the broken pinion stopped the bike immediately. How did you come to learn your final drive was bad other than the dealer mechanic telling you so?
As far as your pattern of "abuse" is concerned, from what I've read that's fairly typical of even the most white haired, geriatric, AARP forum members here, so as long as you kept oil in it and didn't submerge it in Long Beach Harbor for a few days you should've been good on that front. If you can manage, take a better picture of both ends of the broken pinion, particularly focus in on the break under good light. May be able to tell you more with that.
rPGoatBoy
Well-known member
I think what most are trying to tell you is this is completely abnormal and has not happened in hundreds of riders that ride similarly "hard". **** happens, a good data point for sure. But the spirited riding you refer to sounds 'bout right and definitely not a reason for problems. There are m/c with 2-6x the mileage, driving just as hard. This post isn't about anecdotal evidence and more to say this is unheard of with a low miles, hard run FJR. Hmmmm.
