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new flying brick owner '93 K75

rjayson

New member
I just purchased a 1993 k75 with only 8000 miles. From 2nd owner who bought it with 1700 miles. It is clear the only servicing he did was change the oil a few times. The bike is super clean, no oil leaks that I could find after riding for 30 minutes today. My question is.....I understand that it is critical to make sure the drive shaft splines are well lubricated. This bike has very low miles but is 25 years old so would you recommend having the splines lub'd? If so both ends or just at the rear tire end? Thanks in advance for your replies! Rob
 
yes. splines should be lubed.

bike is old. splines aren't the only thing that needs to be done. fuel filter replaced. inside fuel tank inspected. all fuel and brake hoses replaced. z-hose replaced. coolant hoses should probably also be replaced. all fluids replaced. steering head bearings regreased. fork oil replaced. all electrical connectors cleaned. etc, etc, etc.

tires need replacing if more than 5 years old.

at 25 years old, a full refresh is needed...regardless of mileage.
 
My K75 was similar when I got it last year. A 1992 with 12k miles, and I didn’t know if that was a few hundred a year, all in the first six months, or what. I replaced every filter, every rubber line and hose, all fluids, cleaned every electrical connection I could access, etc. I don’t regret any of that, and sure feel better after seeing what came off/came out. The spline condition looked really good, but I’m still glad I did it.

I kept reading that Ks don’t mechanically handle limited use well, but I think that’s true of most things. I just wouldn’t want to ride around with any of those things being an unknown.
 
Jola and welcome.

I picked up a 1987 K75 a few months ago and have been replacing ALOT of rubber!

tires are the most obvious and anything leaking should be top priority.
The fuel pump should be thoroughly checked and all electrical connections.
Also inspect for in-deliberate and DELIBERATE hidden damage. (Turn signals turned out to be junk and had to completely re-wire mine.

Watch for excessive smoke and keep it on the center stand.

Like you the bike is relatively new to me so i am on a huge learning curve here.
Including that the bead lip on the rims are a pain in the backside to seat. Had to have the rear seated by the guys at the Wally world tire center do the job. (My compressor simply didnt have enough umph to do the job.)

The folks here are a huge wealth of knowledge, so be an open book and absorb what you can.

Good luck,.
 
Welcome to brick world. I too bought an old brick in '14. No one wanted it except me. Wrenching is a long curve and the other half of the fun. Get couple manuals, Chiltons/Haynes, start reading stuff online at night instead of sleeping, don't rush out and buy a bunch of pricey parts because it won't start.

It's four years since I started learning about my '84 KRS and just two days ago it wouldn't start, then died on the road. Wiggled the unique to early tank connector, limped back. Found out the NLA connector was too sloppy to keep power to the fuel tank pump.

Of course, the last thing worked on is usually the first thing that doesn't work. Last winter I did a complete fuel system cleansing with new pump etc., and I forgot to check the electical connector to the tank pump.

Online there's a ton of info on Ks which you probably are already reading. The upside IMHO is bikes like these are fixable and most parts, thanx to BMW and other sources, can be obtained.
 
I just purchased a 1993 k75 with only 8000 miles. From 2nd owner who bought it with 1700 miles. It is clear the only servicing he did was change the oil a few times. The bike is super clean, no oil leaks that I could find after riding for 30 minutes today. My question is.....I understand that it is critical to make sure the drive shaft splines are well lubricated. This bike has very low miles but is 25 years old so would you recommend having the splines lub'd? If so both ends or just at the rear tire end? Thanks in advance for your replies! Rob
I just bought a 1993 with 3,000 miles on it, so similar scenario. I did a spline lube on the driveshaft / final drive today. The original lube was still there doing it's job, but i still cleaned it up and applied some Gaurd Dog 525. Not a bad job about 1-1/2. Cheers, Scott.
 

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yeow...that is about 10x the amount of lube i put on splines when i do them....dont need that much. the excess just gets pushed out on assembly and spews everywhere. less is more.
 
Lube is cheap, driveshafts and final drive splines are not. Too much lube has never worn out a driveshaft.:dunno



:dance:dance:dance
 
My question is if plugging the driveshaft as some have claimed is a good idea or is that hollow driveshaft hollow for a reason?
 
Plugging is a good idea and causes no problems.

Ron,

How are you plugging it? I've only heard of the plug Bruno used to put in the driveshafts when he rebuilt them. It was not something that could be used on an intact driveshaft.





:dance:dance:dance
 
Ron,

How are you plugging it? I've only heard of the plug Bruno used to put in the driveshafts when he rebuilt them. It was not something that could be used on an intact driveshaft.


Mine was plugged by Bruno. I think a rubber stopper coated with silicone sealant could be pushed into place.
 
Ron,

How are you plugging it? I've only heard of the plug Bruno used to put in the driveshafts when he rebuilt them. It was not something that could be used on an intact driveshaft.


Mine was plugged by Bruno. I think a rubber stopper coated with silicone sealant could be pushed into place.



Ron,

The plug is past the splines where the inside diameter is larger. He put it in before he welded the new spline section on.

A stopper that seats to the ID of the splines (.795" ID) will be pushed further in by the final drive spline. Just past the end of the splines, the ID of the snout of the driveshaft is 1.143" ID, so the plug would be loose and eventually just rattle around inside the shaft with no way to remove it.:dunno



:dance:dance:dance
 
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Ron,

The plug is past the splines where the inside diameter is larger. He put it in before he welded the new spline section on.

A stopper that seats to the ID of the splines (.795" ID) will be pushed further in by the final drive spline. Just past the end of the splines, the ID of the snout of the driveshaft is 1.143" ID, so the plug would be loose and eventually just rattle around inside the shaft with no way to remove it.:dunno
:dance:dance:dance

If I were to plug one of these driveshafts I would get a can of expanding foam insulation of the type used to insulate around electrical boxes and leaky window frames and such, and fill the driveshaft with it. If the splined portion of the shaft were well greased, removing the expanded foam from the splines would be pretty easy.
 
If I were to plug one of these driveshafts I would get a can of expanding foam insulation of the type used to insulate around electrical boxes and leaky window frames and such, and fill the driveshaft with it. If the splined portion of the shaft were well greased, removing the expanded foam from the splines would be pretty easy.

Paul,

While I agree that theoretically that might work, until someone actually tries it ands sees what unforseen problems or what the long term results are, I wouldn't recommend it to any one, esspecially a newbie like the OP.

There is plenty of evidence that lubing often with the proper lube leads to long spline life. Not so much on how that foam stands up to heat and grease or how easy it is to get out of spines either during installation or over time.

Yes, I had thought of the same method before, but it wouldn't change my schedule of lubing the splines that works well, so why risk it?




:dance:dance:dance
 
Paul,

While I agree that theoretically that might work, until someone actually tries it ands sees what unforseen problems or what the long term results are, I wouldn't recommend it to any one, esspecially a newbie like the OP.

There is plenty of evidence that lubing often with the proper lube leads to long spline life. Not so much on how that foam stands up to heat and grease or how easy it is to get out of spines either during installation or over time.

Yes, I had thought of the same method before, but it wouldn't change my schedule of lubing the splines that works well, so why risk it?




:dance:dance:dance

I don't disagree, Lee. I don't see a real downside but have lots of K miles on stock shafts with not a lot of wear due to lubrication every tire change. It only adds about 15 minutes to my routine.
 
Thanks for all the tips!!!!

Merry Christmas and thank you all for the great tips. I posted my original post the day I made the offer to buy the bike. I was going to pick it up the next week. The owner took it for a ride the next day and decided not to sell. I was bummed. BUT I kept looking and found another one and did buy it. 1995 with 37k miles. most recent owner put 8k on it and kept up the maintenance so I have a good starting point. I do plan to clean it up and look for all the small stuff I didn't catch. I have a few questions.
Is there a youtube on how to remove the gas tank so that I don't spill a lot of gas?
do you recommend taking off the gas tank filler cap to make it easier to inspect inside the tank?
can you recommend a website that offers good quality parts at a a reasonable price?

thanks in advance for your replies.
 
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