Middle Gear drive

[steptoe]

as for the uni joint,,,, all you need is a common as leaves on a tree toyota forklift joint,

40mm across, 20mm caps with internal clips should be sitting on a shelf

[XSIIE]

Dave,
Thanks for the offer.  All fixed with one I dug up from the states.

Eddy

[Clutch]

G'day Eddie,
I have a spare middle gear if you are still needing one, it came from the US so its silver with chrome cover,
The output flange has been removed and I don't know the condition of internals but its yours if you want it.
Clutch.

[XSIIE]

Thanks Doug for the offer,  The shipping from Canada will cost more than the bike. 

I have been down  to the local bearing guy and he has didn't have the UNI in stock.  He will go to his supplier tomorrow and see if he can russel one up for me.  Here's hoping.

Regards

Eddy

[Fred]

Jonesy,

I've always taken old bearings, uni joints, seals and such to CBC for a matchup before I go genuine on all my bikes and cars.
99% of the time they've got an alternative at a huge discount.

[rasputin]

I have a few extra middle drive units around here. Too bad shipping to you fellows is so expensive. A heavy thing like a middle drive would be a huge cost.

[XSIIE]

Jonesy,

The old UNI has some lateral play  when compared with the one off 3131.  The other thing of interest is the rubber boot which protects the UNI from crud has a split in it which allowed shit to get in.  This could have helped in the demise.  I have a NOS boot coming from the US of A from this mob:

http://www.nwvcp.com/pages/OemParts#/Yamaha/XS1100E_-_1978/EXHAUST/XS1100E_(1978_MOTORCYCLE)/EXHAUST_(XS1100E_-_1978)

 The UNI is not available from them.

Took the bike for a test ride around the block with the 3131 middle gear unit in and it was the same as when  I rode it to Bathurst,  So on the road again but i,; going to replace the worn bits when they arrive.

Eddy

[Jonesy]

Hey Eddy
just out of curiosity, how does the old uni joint look? need replacing? or just doing it as a matter of course?

[XSIIE]

Spoke with the local CBC fella today.  He has my universal and will talk to the reps on Monday to get a match.  I'll keep you posted.

Eddy

[Jonesy]

Good tip Fred,
how did you come across that one, I've got a CBC shop just down the road and might have add one to my spares shelf

[Fred]

eddy,

if you're looking for new uni joint there is no need to go genuine.

CBC Bearings sell one that fits perfectly at a fraction of the cost of yamaha.

"U/J Kit TOYOTA T.C.M.  RUJ-0603

[XSIIE]

Hey Jonesy,

Replaced the complete middle drive unit donated by 3131 (I'll replace that one when one pops up).

Yes I reused the same uni joint

No vibration on Idle

Heaps of vibration and clunking going through the gears while on the centre stand

Didn't want to take it for a ride in case I rooted it totally.

I see where you're coming from and will take her for a ride and look at replacing the universal.

The noise (listening through a bearing stehtescope seemed to be localised in the cases but I'll eliminate the other stuff first.

Thanks for the tips

eddy

[Jonesy]

Coupla questions Eddy
Did you strip the gear from a spare drive and replace the rooted one or did you replace the complete middle drive unit.
Only a hunch but I'd be thinking the damge would be contained to just the middle drive unit
Bearings #5 & #7 should support the input shaft of the middle gear and preventing damaging bent/broken shaft forces transmitting to the main gearbox.
Did you re-use the old uni joint and drive shaft? the remaining vibration might be from these?
Is the vibration thats left just with the motor idling over in neutral? running through the gears while on centerstand or riding?

sorry for so many questions but thats just fault finding and trying to build a picture.

[XSIIE]

Hey Fred,

The nut has shaft has sheared off at the base of the thread so no thread left. 

Now that the Middle Gear Drive has been replaced by one from my other bike does the true extent of damage manifest itself.  In a nutshell my gearbox is rooted.  There is still heaps of vibration within the crank cases at the middle drive section.  I can only assume that when it went bang! it had bent/damaged some internals in the gearbox??.

I will need to investigate further.

Cheers

eDDY

[Fred]

Eddy,

just trying to visualize this problem.

I presume that you mean the self locking nut (22mm) at the end of the pinion external to the flange. Now, when you say it is sheared off, has the thread on the shaft broken off or has the nut worked its way loose?

I've had the nut work its way loose twice after I replaced the oil seal and the first indication is an oil leak out of the drain hole in the bottom of the rubber boot. This oil leak occurs due to the nut loosening thus allowing play in the pinion shaft which then destroys the oil seal.

I've cured the problem by replacing the nut with a new self locking one (still available from Yamaha), and torquing it up to the required 72 - 108 ft-lb (dependant on model, my '78E to 79.6 ft-lb).