Scheduled maintenance questions

I'm off to buy supplies for scheduled maintenance tomorrow. I'm lucky that there's a Airhead parts guy nearby. I'm making a long list and had a few questions to ask of the wise(r) vets .

A little bike info:

1975 R90/6. No problems I can detect. I runs & rides fine. There are a few minor points that need addressing (new tires, oil change, etc). The PO owned the bike ~15 years and put about 1000 mile/year. The last service was 18 months ago and was basically an oil change and tune up.

On to the questions:

I think I read somewhere that I should replace the 2 exhaust gasket rings on each exhaust pipe once a year. True or false?

I'm replacing the tires and have decided to mount them myself. I've ordered a Marc Parnes wheel balancer. I'm going to mount the tires by hand. If it's too hard I'll run down to Harbor Freight and get a tire changer. The wheels on the bike have both spoke and adhesive weights. Can someone explain? Do you use one or the other? Both? Are the spoke weights just for the wheels and the adhesive weights for the tires? Please enlighten me.

The tachometer needle swings +/- 500 (max) RPM whenever I hit a bump. The bigger the bump, the more deflection. At a constant RPM and a smooth road the needle holds steady. Also, any throttle input (plus or minus) will have the same effect. A friend suggested I need a new tachometer cable. What say you?

TIA

subagon said:

I think I read somewhere that I should replace the 2 exhaust gasket rings on each exhaust pipe once a year. True or false?

Click to expand...

Huh? Never heard of that. I think you probably should undo the exhaust nuts and apply antiseize to the threads. Be careful when removing the nuts...it they turn and then seize up, stop...the threads are beginning to gall. You'll need cut off the nut.

subagon said:

The wheels on the bike have both spoke and adhesive weights. Can someone explain? Do you use one or the other? Both? Are the spoke weights just for the wheels and the adhesive weights for the tires? Please enlighten me.

Click to expand...

You really only need one of the other. Spokes are great because you can use the weights around them...I never liked the adhesives.

subagon said:

The tachometer needle swings +/- 500 (max) RPM whenever I hit a bump. The bigger the bump, the more deflection. At a constant RPM and a smooth road the needle holds steady. Also, any throttle input (plus or minus) will have the same effect. A friend suggested I need a new tachometer cable.

Click to expand...

Could be a cable. Could be the cable is not firmly attached on either end. Could also be the tach. Try some lube...I forget whether your supposed to do that or not...some BMW cables are teflon lined. If that doesn't help, move on to a new cable. Lastly, find a decent repair place...several around.

Q1: gaskets.
don't touch them. if it ain't broke...

Q2:tire & weights.
do them yourself or have a bmw shop do them.
most 'moto tire' shops have monkeys working there. do not trust them.
this is why you have "spoke and adhesive weights". monkey probably didn't see them. let me guess; all the weights are spread out all over the wheel instead of only in one spot.

Q3: tach.
500 on a bump? consider it a prime example of a fine tach working properly.
why would a cable have anything to do with that? the needle is SPRING loaded!!

danielroth is 100% correct on all points.

1. Leave exhaust alone, other than to loosen the nuts and apply antiseize. But, if they will not move, using the appropriate wrench, then just leave them alone until you need to replace exaust. They are not hurting anything if there are no leaks.

2. Remove all weights. Remove tires and install new tires. Ballance accordingly using spoke weights.

3. Tach will bounce around a bit going over bumps. As Dan said, it is spring loaded. Leave it alone.

Once all is done, get out and enjoy the ride.

Thanks for the info guys. I when to Hucky's Spare Parts and Hans set me straight.

• I ended up with some antiseize for the exhaust (already had some in the toolbox).
• A leason on wheel weights. Short story, use the spoke weights only and they are re-useable.
• No tach cable. May be a srping in the tach. Just enjoy "viva la difference".