K11 Owners Group

[tibbe]

Hi

Like to test an idea.
Seen two broken driveshafts since summer.

One with broken U-joint at the final drive, it sounded bad and the rider stopped the bike. Then the bike was blocked while pushing forward.

The other bike was a K11RS with broken front U-joint. As the U-joint broke it jamed into the tranny case and blocked the rear wheel. Bike probably slipped on the side and took fire.

Have some theories.
- The splines in the driveshaft runned dryed and stucked coursing a huge axial force on the joints.
- The shaft not assemblied with the two joints not in line coursing an uneven speed of the driveshaft and a thereby a dynamic force on the joints.
- Just plain overload by accelerating with slipp on tarmac ( and a bit of sand )
-
-

Any opinion on this?

[Shoganai]

"Most universal joint failure is a result of lack of lubrication. When the universal joint lubricating grease breaks down, or is contaminated by dirt or moisture, the needle bearings rapidly wear. This can result in a squeaking sound, as the vehicle slowly accelerates, and may result in driveshaft vibration. Most vehicles today do not have lubrication fittings on the factory equipped universal joints. However, almost all replacement universal joints are equipped with lubrication fittings."


This seemd to make sense.

http://www.auto-repair-help.com/automotive_maintenance/driveshaft_ujoint.php


So, I think the u-joins should be lubed when doing the spline lube.
That's what I'll do from now on.
_________________
1993 K1100RS aka The Shop Whore
1994 K1100RS aka Blue Streak

The long road is a rainbow and the pot of gold lies there.
So slip the chain and I'm off again,
You'll find me everywhere. I'm a Rover. - JT


Nana korobi ya oki

[garynali]

Gday Tibbe
Just had the front universal fail, see my previous post. I agree with all you say regarding the possible causes and can add a biggie. BMW's design of the drive is just bad engineering.
A major subsystem with predictable failure modes that is uninspectable in situ and unable to be lubricated without major disassembly. How much more servicable would the bike be with grease fittings on the joints and access ports front and rear to do all the required lubrication and inspection.
I wonder how many riders have suffered serious injury after a failed drive shaft locked up at speed.
On the positive side I got a new shaft assy from Motobins at a good price with great service and delivery. Britian to Aus in a week. Hope to have it going next week.
Gary C
K1100RS

[Rafal]

[tibbe]

Quoted from: http://www.hurst-drivelines.com/files/Universal_Joint_Alignment_Proc_111606.pdf
"U-joints do not turn at an even speed.
The greater the angle, the greater the speed or velocity changes as the driveshaft turns. In other words, as the ujoint travels around to the outside of its angle it slows down. When traveling through the inside of the angle it speeds up. The greater the operating angle is, the greater the speed difference is. Having the opposite ujoint at the same, but opposite, operating angle cancels out this speed difference and keeps harmonics to a minimum."
IMHO it's possible to assembly the driveshaft so that the ujoints can have any angle relative to the other ujoint. This can give vibrations and increased wearing. If it's matter that's another Q
Will put a colour dot on the both parts of the driveshaft when its assembled outside the bike.
A note. it's a snap ring on the output shaft of the tranny. When the driveshaft are correctly snapped in the backflange of the shaft should rest exactly at the tap in the swing tube. And NOT rear of the tap.
Will do this alignment, marking and lubing on a driveshaft this week as we have to shift a gear indicator,, oh yes Ted we will take photos.

[max]

I've always "phased" (lined up) the universals - even if it's urban legend, it doesn't cost anything - and have put a little notch in the rear end of the driveshaft so I can easily know where the front UJ is even when the swingarm is on - eg don't worry at all until the final drive is about to be "offered up"...

- be ready to fit the final drive
- make sure the *&(^$!ing gaiter is in place on FD (been there, caught out too)
- put bike in 1st gear
- push in on clutch (rear actuator lever) and wiggle driveshaft marking to 12 o'clock position. Let clutch back out, it's fixed now apart from gearbox play
- setup final drive with rear UJ having one set of "arms" of the "spider" running horizontal - can check them thru the pivot holes, you see...
- hold brake disk to FD body to lock it until engaged
- get splines engaged with as little change as possible
- check with torch thru pivot hole once one pivot pin in place as final check

Shogs - how are you lubricating the UJ? - not the splines, but the UJ itself? I thought the silly little needle-bearing "cups" were sealed for life? Have thought about it - my mileage is getting up - but even if you drilled a fine injection hole and used a cone-head tip on the grease gun, you've still got the hole for the grease to then get thrown out from (and tapping a hole as small as I'd want would be beyond fiddly!!)

Max

[Ernie-NH]

Good morning "tibbe"....

Say... while you're doing the 'drive shaft' work... pictures would be nice and very handy for the rest of us !! It would also be a real addition to our permanent "stickie" collection !!

Thanks in advance .......// Ernie in NH
_________________
AMA,, American Deaf Bikers
Airhead Beemers Club
'11 G650gs
'95 K1100LT
'76 R100/7

[tibbe]

Oh we did some wrenching yesterday evening, but no photos.
It was kind of wrenchtherapy session as my friend and owner of the bike lost his father on wedensday and we kind of focused on wrenching and when needed spoke a litle about life.
On the other hand it was a fairly straitforward proceduer to install the gearindicator and reinstall swing, finaldrive...
Will try to take some photos next time, can be that I need to renew the final drive 2 swing bearrings and maybee also the big bearring in the final drive in some weeks-mounths.
Time for the last trip of this season a 200+200km trip to finland with the local BMW-klubb. And in not so many weeks we can have ice on the roads in the morning and the first snow could come.

[Ernie-NH]

God morning again "tibbe"...

Sorry to hear about your friends loss. Please wish him well and many condolences from all of us here at KOG ! It seems, time well spent in the company of a good friend is always the best therapy.

The reason I asked if you could take photos is simply that whenever one of us does any form of major repair or replacement, it helps all of us avoid the pitfalls when it comes time for us to do the same.

Hoping you have fun on your last ride of the season before winter, for us here in New Hampshire it will soon be our time to put the bikes away as well.

Very best regards...........// Ernie in NH
_________________
AMA,, American Deaf Bikers
Airhead Beemers Club
'11 G650gs
'95 K1100LT
'76 R100/7

[tibbe]

Hi Ernie
You know there's something nice with this MC-friends, when someone needs support after a hit in life it's easy to take him/her on a ride or wrenching no need to talk so much. It's more doing things together in a relaxed manner.
I'm also a member of EuroPrez a spinoff from IBMWR and one of our prez flow down to za as a beemer-biker was killed on the road. The widow flowed up last summer to be at our annual meeting riding a bike from Antwerpen to appr. Prague. At the funeral of my wife 2 y ago 3 EuroPrez came from Germany and Belgium. And 3 days after the funeral my friend, who needed a wrenchingtherapy and another biker took me to a rally in norway. That's just how we do to support eachother. Ted when I mention Antwerpen you probably guessed who that prez are.

Over to pictures and story. I need to understand how to write a story with pictures, what to tell and at what wrenching skill level. As I taken out the swing appr. 5+ times it's some of the steps falls natural. Yesterday I was sitting on a chair most of the time and only telling the owner what the next step should be to avoid doubble work and damages. Have to think about this with story and pics as I plan to do renovate the final drive on my bike.

About the riding to finland tomorrow will take my bimmer ( car ) as I got a coold and the weather can be a bit chilly.

BTW. will replace the xenon head light with Philipps H4 xtreme lights due to regulations and to get the radio running again.

[merlin geikie]

Tibbe writes;

[CrashBar]

My rear universal blew at 99,550 miles, 200 miles into my cross country trip last year. Now I carry a spare driveshaft and universal joint, as well as tools (27mm socket and ratchet, I think) and lube to fix it on the way.

Good news is that after a winter tearing everything down to the main seal, I've run 10,000 miles this summer (Boston to Natchez LA and back, Boston to San Francisco) without a problem.

Oh yea, if you are real paranoid, a spare final drive will fit in the bottom section of the standard K11 tank bag (DAMHIK).

CB
_________________
1993 K1100LT (116,000 miles and counting)
1973 Honda CB350F
1978 Honda CB550K
1973 Triumph TR5T

[tibbe]

Have to admit I took the bimmer to finland Well it's a BMW but has 2 wheels to many. A 3 weeks cold with a lot of caughiing and a bit chilly outside. A tiny snowfall on the way back yesterday.
Else trip was great - sauna with a lot of wisdom to share - so much that we have to continue over dinner and aftertalk until midnight.
http://picasaweb.google.se/luletibbe/BMW_Finland_oct_10#

A few picks from installing heated grips and replaceing the gearindicator:
http://picasaweb.google.se/luletibbe/Mek_Handle_gear_ind#

Will put my "flying coach" into winter garage this week.
Will put it's centerstand on a 4 wheel lowbuild wagon so it's easy take it out and do a bit of maintanace and adjustment.

[SugarHillCTD]

Had to resurrect this thread since I took my fd off this morning to inspect. I find the "physics" of the following statement very hard to understand.

[robleyd]

I think it is more a matter of different rotational speeds between input and output sides - http://en.wikipedia.org/wiki/Universal_joint has a very technical explanation. Bring your mathematical hat

You might also find some further gems from http://www.google.com/search?hl=en&q=universal+joint+phasing
_________________
David, owner of:
1996 K1100 LT

[Ted]

[1960mog]

I did a little drive shaft phasing experiment.
Notice how the u joints are aligned in the pictures.
In the first picture the output shaft slows down and speeds up twice a turn.
In the second pic the output shaft turns evenly.




_________________
86 R80G/S
91 K1
93 K11LT

[merlin geikie]

That is the GO...

Nothing like a real life model,

Beats the Cra@ outa theoretical explanations

Thanks very much MOG

greeting from downunder oz, sunny riding weather