routine Maintainance on a 20 year old bike

[hoodun]

I'm almost ready to ride my newly purchased K75. So far I have done the following:

New tires and valve stems
flushed radiator
replaced brake fluid
new oil and filter
gear oil and tranny oil
boot repair and clutch shaft seal (tranny was covered in oil...)/ rear seal seemed ok
new brake pads
new spark plugs
wash and shine

Unsure of the wether or not I should replace the brake hoses and spark plug wires. I am not planning on keeping the bike long. At least that is what I say. I do, however want to make sure whoever gets it next, gets a safe ride. That said, my 1975 R90 that I just rebuilt had the originally brake lines and spark plug wires (40yrs old), and both were still working.

What are your opinions on replacing the wires and hoses on a 1994 K?

[Grim]

Does it look like somebody maintained it or total neglect? Maintained and looking like the brake fluid has been changed regularly the brake lines are probably ok if your not seeing issues with the exterior. That said...they do rot from the inside out and neglecting brake fluid flushes allows the fluid to become acidic and eat at the linings.

These bikes make 40PSI of fuel pressure.  Replace the fuel lines and filter. It can be replaced with regular high pressure fuel line from the local parts store and cheaper then the molded lines from BMW.  Search in the Lieberry and there will be alternate fuel filters listed available at local parts stores.

Plug wires you can test with a Multimeter easy enough. I forget what the resistance should be for a given length but if they all measure close (the longest will be higher) and the insulation looks in good shape then run them.

I'm still trying to decide on coolant hoses this winter on my 95. Pretty well stuck with the insane prices from BMW on those. They rot from the inside out. Lack of coolant changes will accelerate.  I'm probably going to suck it up and do it. Hot coolant spewing on you at 70mph 200 miles from home brings the suck. Finding these hoses on the road...pretty well impossible.

Pull your air filter and inspect. They are oversize and can go a pretty good while before needing a change. I don't know the history of my bike but the filter that is in it at 46k didn't look all that bad but I don't know when it was changed before I got the bike.

Id recommend doing both a drive shaft and clutch lube if you dont have proof they were done in the last 20k. Mine as far as I can tell had not been done ever and I was starting to get wear on the transmission input shaft and more on the clutch . Its bade enough that in 20K Ill be replacing the clutch disc.

Pull, clean and die electric grease all your electrical connections. A lot of intermittent issues with these bikes get traced back to corrosion in connectors.

Ride the piss out it for the next 20year  rinse and repeat.

[Scott_]

Personally, I'd replace the brake lines and coolant hoses. They not only can they chemically rot from the inside, but they can dry-rot from the outside with exposure to the sun. There all kinds of rubber bits that get real finicky as they age.....like us.... :hehehe
Especially brake lines and coolant hoses as they can and do flex.

I replaced all of my coolant/vacuum hoses, fuel/brake lines, o-rings, on my '95LT 2 yrs ago and plan on doing the same this year to my '97LT.

I wouldn't ride on 20yr old tires, and I think by law here in the states they are not even allowed to be sold if they are over 5 or 6 yrs old. Tires are rubber too.....

As far as the spark plug wires, I seem to remember reading somewhere that the K75's had different plug caps on them with a spark gap or resister in them. Someone correct me if I'm wrong. Not sure you can test them with a regular Ohm meter.... Nor can you replace them with just any spark plug wire. There are mfgr's that make them aftermarket so you don't have to go BMW on those.

[Chaos]

Spark plug wires are obscenely expensive for a K75, I'd leave them alone if you're not having issues.  Coolant lines seem to last forever, mine are original 1986 and are still in excellent shape.  Other K gurus agree, no need to replace them, except maybe the line from the radiator cap to the overflow bottle.  Brake lines have been know to delaminate from the inside and cause all sorts of problems, can't hurt to replace them, fuel line definitely.

[mystic red]

If you go with Magnecor wires instead of OEM they are $25 a wire instead of $40 something. ...  :-)

[Motorhobo]

Those OEM wires are over $80 apiece at the dealer these days. Apiece...i.e. over $240 for a set of three  :mbird