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Considering adding a 92 K75

. jconway607
.........Just when did "low balling" everything become the norm?...........

That was when dishonest people, crooks and genuinely weird people first started to sell anything and are looking for the “Fool and His money are Soon Parted” type buyer.


Don't know many BMW models, but I do know a little about K75’s and ALL are a “Pig in a Poke” until you get to look into the Poke, due to the the clutch spline condition.

I tend to think a K75 is worth $500 less than initial asking price for just that reason, before any other evaluation. All mileages too.

Charlie
 
Don't know many BMW models, but I do know a little about K75’s and ALL are a “Pig in a Poke” until you get to look into the Poke, due to the the clutch spline condition.

I don't agree. Driveshaft splines wear. One batch of early - mostly '87 and '88 units had mis-machined auxiliary cases causing rapid clutch spline wear.

The two known problems are the driveshaft splines as noted and the cooling fan motors. Lubricating the splines every rear tire change eliminates that problem. The fan motor issues are due to crud in the front bushing and re lubricating every 50,000 miles or so usually prevents that problem.

Indeed, the clutch splines should be cleaned and lubricated every 40,000 to 50,000 miles, just like the Oilhead bikes. Except, with a K75 it can be done in about 3 hours without needing to disassemble the rear half of the motorcycle. That is also a lot better than the /6 and /7 Airheads where BMW recommended a spline lube once a year.

The K75 is among the most reliable models BMW ever built.
 
I don't agree. Driveshaft splines wear. One batch of early - mostly '87 and '88 units had mis-machined auxiliary cases causing rapid clutch spline wear.

The two known problems are the driveshaft splines as noted and the cooling fan motors. Lubricating the splines every rear tire change eliminates that problem. The fan motor issues are due to crud in the front bushing and re lubricating every 50,000 miles or so usually prevents that problem.

Indeed, the clutch splines should be cleaned and lubricated every 40,000 to 50,000 miles, just like the Oilhead bikes. Except, with a K75 it can be done in about 3 hours without needing to disassemble the rear half of the motorcycle. That is also a lot better than the /6 and /7 Airheads where BMW recommended a spline lube once a year.

The K75 is among the most reliable models BMW ever built.


Paul is the expert here, but I have two K75s now, and have a third for a while, and I totally agree that it requires moderate maintenance that if done on a schedule will eliminate any between services issues. Gas and go. However, when looking at a used K75 I would pull the rear dive and check out those splines before buying, unless I had complete confidence that the seller had regularly serviced the read drive splines.
 
Paul is the expert here, but I have two K75s now, and have a third for a while, and I totally agree that it requires moderate maintenance that if done on a schedule will eliminate any between services issues. Gas and go. However, when looking at a used K75 I would pull the rear dive and check out those splines before buying, unless I had complete confidence that the seller had regularly serviced the read drive splines.

I don't disagree with Greg on this. The driveshaft rear spline connection to the final drive is the single most serious weak spot on K75s but it is easy to take care of, adding about 20 minutes of time to a rear tire change.
 
Off topic a little but:
My personal experiences with clutch splines on K75’s do not make a trend or an epidemic.

I bought a new 1992 K75 after BMW claimed to have remedied the failure of the clutch splines. It was not the only reason for purchasing one at that time. The Splines failed at 36,000 mi. BMW balked at repair on their dime but did agree to pay for parts; ONLY after I sent them a copy of the Owners Manual. They knew that before I told them. The Manual that came with the bike that stated Service Splines at 40,000 mi. and not failure before 40,000 mi. (I Really didn’t think I should have had to pay labor also but........)

The local dealer serviced a newer year model K75 a year or two after that for a broken down traveler on the Blue Ridge Parkway. That Bike had 5,000 mi. on it. There were NO splines left on the clutch plate. As in Smooth. I still have it. It’s Yard Art now.

The Tech boys at BMW have recommended at least 2 types of lubricants over a period of time, probably because they were still having problems. The independents and owners had their own special mixes.

It was a hot topic for several years because splines were something to be addressed; especially when planning a long trip.

Wonder how a BMW car owner would feel about that sort of reliability ?

If you don’t do you own service work (I do), then you have to pay someone to do the inspection. So at the least, you could consider dropping the price by $250. If you’re buying on emotion (I have done that too) then don’t worry about it.

I still deduct $500 for the “Poke”.

Charlie
 
The Tech boys at BMW have recommended at least 2 types of lubricants over a period of time, probably because they were still having problems. The independents and owners had their own special mixes.

Charlie

This is so so true! BMW's track record with spline lubricants is almost a joke. They actually specified anti-seize at one pont, back when they said that Airheads should have the splines cleaned and lubricated once a year. It sort of lubricated but totally failed at preventing corrosion. Once a year was about right. Then they specified BMW #14 grease. This stuff was Texaco Starplex actually, and works on ball joints but certainly not on splines. It totally lacked high temperature qualities and would actually melt and ooze in a grease gun at room temperature. Next they tried one version of Staburags assembly lube. All the way through the R1150 models they never specified a decent clutch hub spline lube in my opinion. I had to concoct my own mix of grease and moly, and then work with the owner of Guard Dog Moly Lubricants about what characteristics were needed for a good spline lube.
 
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With respect to splines. I've often wondered if part of the problem was number of splines on the input shaft/clutch. They are a fairly fine spline and a coarser spline like on the Moto Guzzi's might help as they don't seem to have similar issues. Manual clutch cars/trucks go for a long time with no preventative lubing.

I have a bunch of old BMW Service Bulletins and one from 1984 with respect to K100's recommends Staburags NBU 30 PTM and it came in a tube or a spray. Another one dated December 1986 Covers Clutch Spline Failure for All K models and it references the locating dowels in both the bell housing and engine joint and in the transmission to bell housing joint. If they weren't in the right places you'd have miss alignment and premature wear of the splines. So the spline issue was certainly an issue in the Airheads and continued on in the K's and is still somewhat of an issue even today. Although I think drive shafts issues are getting up there.

For whatever reason some bikes, with little or no maintenance seem to last a long time without issues. I don't know if it is rider related, load, heat etc but these certainly play a role.
 
Cycleman,

I have noticed a similar pattern of wear vs spline size by monitoring ebay driveshafts. You almost never see a worn early 16 spline driveshaft on ebay. Over 3/4 of the later 20 spline driveshafts for sale over the past 5 years or so show significant wear. There are many factors involved, but there is a pattern that I've noticed.


I initially started using Honda Moly 60 around 15 years ago, when I got my first K75S. Shortly after that, I started working on other peoples K bikes including tire changes. I would always do a rear spline lube when ever replacing a rear tire. I started adding the Wurth 3000 at Paul's suggestion. Splines would show virtually no progression of wear (unless they were very worn at first service) between service.

About four years ago, after watching one of Chris Harris's videos, I decided to buy some of the Staburags NBU 30 PTU as someone was selling small quantities on ebay. I put it on a long time customers rear splines. Three months later, he was hit by a right hand turner from the left lane (not the Staburags fault).

During the rebuild, I removed the final drive to find that the Starburags was GONE and the splines were dry! I will never use Starburags again. While the Guard Dog Moly that Paul helped get to market is no longer available, a successor to it, made by the same company (TS Moly) is available here:
https://www.beemershop.com/product/ts-60-spline-lube.html

As far as clutch spline misalignment, I had a good riding buddy that had one of the Dakar Yellow '94 K75Ss. He had 60k on the bike and was begining to experience shifting issues. I recommended a clutch spline lube. Upon disassembly, I found the clutch splines severely worn and tapered. He then informed me that that was the same problem that the dealer had found when they replaced the clutch at 30k.

Being aware of the intermediate housing problem that had always been attributed to bad machining, I removed the housing and drug out my surface plate and indicators. The housing checked out to be perfectly parallel. Thinking that it might be a side to side misalignment, I made a target that would insert into the pilot bushing in the engine output shaft. I then made a punch that would go through the clutch push rod hole. The plan was to see if they would be on center. BUT, in the process of reinstalling the alignment dowels in the intermediate housing, I noticed a large burr half way down one of the holes that would cause the dowel to not fully seat. This caused the dowel to protrude farther than the hole on the engine block or transmission (don't remember which side it was on) was deep. This was the cause of his misalignment. I can imagine this happened after Klaus's lunch at the Biergarten and his return to the assembly line or someone not paying attention to details on a very simple mundane task. Grab dowel, hit with hammer. Grab dowel, hit with hammer. Not noticing when one was slightly crooked when he hit it.

After cleaning the hole and replacing the clutch and input shaft in the tranny everything was fine. At his next clutch spline lube and spline check 30k later, the splines were perfect.





:dance:dance:dance
 
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