awful news

Hey fellow riders-

Awful news, my 93 K75S just had a meltdown- Was riding this weekend and out of nowhere it got real grindy real quick. Was actually coasting at the time and I suddenly heard grinding / rumbling in second gear. I pulled over and shut off the bike. Looked at everything and nothing obvious. Clutch cable was fine and the lever at the tranny was actuating fine. Started the bike again with clutch in -in Neutral, everything fine. With the clutch in, I put the bike into 1st and awful grinding.shut the bike off and called for a tow. Bike is at the dealer now-

Any ideas? I wish I knew what was actually grinding- It feels like the dreaded spline failure, but I honestly dont understand the details of the clutch enough to really know what would be happening If so, what should I expect? Regardless, Im sure big $$$, not sure what gets replaced with this type of thing. If it's splines, Ive read about new intermediate housings possibly helping? What sucks was the bike was riding perfect, no erratic clutch operation or downshifting problems or anything out of normal. Just had the splines lubed maybe 5k miles ago by the dealer Any input from the collective wisdom on what I should expect would be super helpful. Vito

Vito said:

Hey fellow riders-

Awful news, my 93 K75S just had a meltdown- Was riding this weekend and out of nowhere it got real grindy real quick. Was actually coasting at the time and I suddenly heard grinding / rumbling in second gear. I pulled over and shut off the bike. Looked at everything and nothing obvious. Clutch cable was fine and the lever at the tranny was actuating fine. Started the bike again with clutch in -in Neutral, everything fine. With the clutch in, I put the bike into 1st and awful grinding.shut the bike off and called for a tow. Bike is at the dealer now-

Any ideas? I wish I knew what was actually grinding- It feels like the dreaded spline failure, but I honestly dont understand the details of the clutch enough to really know what would be happening If so, what should I expect? Regardless, Im sure big $$$, not sure what gets replaced with this type of thing. If it's splines, Ive read about new intermediate housings possibly helping? What sucks was the bike was riding perfect, no erratic clutch operation or downshifting problems or anything out of normal. Just had the splines lubed maybe 5k miles ago by the dealer Any input from the collective wisdom on what I should expect would be super helpful. Vito

Click to expand...

Vito - there are two sets of splines to be concerned about on a K bike
(and especially a K75)

1. The clutch-transmission input shaft splines
2. The driveshaft-rear-drive-input shaft splines

Either can cause the symptom you described.

Usually - if #1 is the cause - you might have noticed a reluctance
on downshifts before the failure occured - usually the 3-2 shift
becomes more difficult.

If #2 is the cause - there is no warning.

So - what to do (and this will be for general info - not specifically
for your bike)

If you own a K bike, and especially a K75

1. At a minimum of every other rear tire change - pull the
rear drive off and grease the splines. Doing this faithfully
using a good lube (I recommend Honda Moly-60 - made for
splines on a Goldwing) - the rear-drive splines should
last for 100k miles.

If you ignore these - they WILL wear. No if, or, but about it..
They need regular greasing at a minimum of every 20k miles.

DO NOT use BMW #10 lubricant if you have it. It does not
work and was a mistake on the part of BMW-NA.

2. If you have a K75 - that has gone more than 20k miles
without a transmission spline problem - you can expect that
with lubricating the splines every 30k or so miles - the
splines will last the life of the bike (Paul Glaves sent me
photos of the splines on his K75 - Old Smokey - recently
destroyed by a bezerkers driver - at 370K miles - the
clutch splines looked brand new. Paul was diligent about
lubricating them and had no contributing problems.)

If you are not this luckly - you may experience a failure
of the clutch/transmission splines somewhere between
15k-18k miles. The usual dealer response to this was to
simply replace the clutch disk and the transmission input
shaft (probably at about $800-1,000). This corrected the
immediate problem - but didn't cure the cause.

The cause has been found to be a distorted intermediate
housing (what on a car would be called a "bell-housing",
where the clutch assembly lives), or in some cases a
housing that was bolted up to the engine after the sealant
that was supposed to seal the two had partially hardened.

In either case - this causes a misalignment of the clutch
center to the transmission shaft - causing a very distinctive
wear pattern on the splines.

The fix - replace the intermediate housing along with the
worn parts.

In some cases, owners have gotten some financial assistance
from BMW-NA on this problem. Playing nice with your dealer
is the best way to encourage this. The dealer input to BMW-NA
is vital for any type of out-of-warranty situation.

So - Vito - I hope you can report back that it was the driveshaft
rear-drive splines that went bad. These can be remanufacturerd
by two sources I know of - Hansens BMW in Oregon, and a
chap named Bruno in Canada. Both do excellent work and provide
a product superior to BMW's original one IMHO... at a lower
cost then the parts and rebuilding of the rear-drive that a
dealer will typically undertake.

HTH,

I appreciate your input Don- I've learned a great deal from your prior posts.

I lubed the rear myself a tire change ago and there was wear but it looked ok to me (I'm not an expert though). I actually looked at some pics you had posted of wear on a shaft you had done. I used Honda Moly. What concerns me though is the grinding was with the clutch engaged (handle pulled, maybe that's called disengaged). With the clutch pulled in, the tranny and drive shaft should be quiet. When I put it into first it was a heck of a ruckus- the bike didn't jerk though- Interesting, I've put about 20k on the bike, bought it with 16k. hmmm...

At least I've got an idea on $$$- sounds like it might be worth it to replace the root cause of the issue if that's what it is (housing)- We'll see what the dealer says- I'm not confident enough to do this work yet...but I like to be informed. -V

Not intending to raise your hopes, but one other possibility exists. But a brief story first. On the way to Redmond, 4 bikes riding together. In the middle of North Dakota the lady riding the K75T(who was our fuel guage) pulled to the uphill off-ramp to a gas station. Upon stopping she attempted to ride down to the gas station, but heard the dreaded sound. We got the bike to the station, expecting the worst, but instead found that the rear female spline of the driveshaft had split, enough that it would not fully engage the male spline on the rear drive. As fortune would have it, the clerk's brother lived nearby, and he builds off-road racers. He tacked the shaft together, then made a sleeve around it and welded it on, ensuring it fit within the rear drive housing. He didn't charge much, either. We were back on the road in 2 hours. Later a replacement driveshaft was installed.

Hope for the best!

Vito said:

I appreciate your input Don- I've learned a great deal from your prior posts.

I lubed the rear myself a tire change ago and there was wear but it looked ok to me (I'm not an expert though). I actually looked at some pics you had posted of wear on a shaft you had done. I used Honda Moly. What concerns me though is the grinding was with the clutch engaged (handle pulled, maybe that's called disengaged). With the clutch pulled in, the tranny and drive shaft should be quiet. When I put it into first it was a heck of a ruckus- the bike didn't jerk though- Interesting, I've put about 20k on the bike, bought it with 16k. hmmm...

Click to expand...

Unfortunately - that mileage interval seems fairly common. Someone has the problem, has the dealer fix it (and most dealers do NOT know or recognize what the cause of the problem is) - then they decide to sell it and the 2nd owner gets to experience the same problem.

At least I've got an idea on $$$- sounds like it might be worth it to replace the root cause of the issue if that's what it is (housing)- We'll see what the dealer says- I'm not confident enough to do this work yet...but I like to be informed. -V

Click to expand...

If you do it - you really DO want to do the housing - or the same problem WILL occur in another 16-18k miles. There was one person on the IBMWR list who did it twice before realizing that fixing the symptom and not the problem was getting awfully expensive. Play nice with your friendly local dealer (coffee and donuts is a good start.. perhaps a 6 of some decent german beer) - and see if they can get BMW-NA to cooperate. In cases I've heard of - BMW has paid the cost of the new intermediate housing.

Best,