Pre-Restoration Questions

[Jeff in W.C.]

I’m in the planning process of restoring my 88 R100 RT over the winter.

The bike is ±34 years old with ±105,000 miles and some things are original. The plan is to powder coating the frame, go through the important systems and rebuild them, and give it some fresh paint.

With regards to brakes, my thought is to rebuild the master cylinder and brake calipers in addition to replacing old brake lines. However, both master cylinder and calipers appear to be working fine.

In rebuild process, I’m planning on replacing the timing chain, so all seals and gaskets will get replaced. Also while things are apart, I’m thinking on replacing the rear main seal, since its 17 years old.

I’m on the fence regarding the transmission and final drive. While both are working great the seals and gaskets are 10-15 years old. FYI, working on both of these are beyond my expertise and I would have to ship these off to have them worked on.

What are people’s thoughts? Should I be proactive and rebuild the master cylinder, calipers, transmission, and final drive or wait until the seals and gaskets start leaking? Or, should I be proactive and get them working like new?

On a different note, I know I’ve read of people’s suggestions on restoring the look of the engine, but I’ve not been successful in locating the previous discussions. What are people doing to restore the exterior look of the engines (dull grey aluminum to more shiny aluminum)?

[gspd]

How much do you want to spend?

New parts are better than old parts 99% of the time.

That said...
...I personally wouldn't worry too much about transmission and final drive seals and gaskets that ARE NOT leaking.

As for the brake system...Change the brake fluid. If after bleeding you get a good solid lever and no leaks, it's OK for now.
The ancient flex hoses are probably somewhat hardened, and should be replaced on principle, especially if there are any visible cracks or other visible signs of aging. If you can squeeze and hold the lever with all your strength (like way harder than any imaginable panic stop) for a minute or two, and there are no leaks or signs of hoses ballooning or brakes sticking, it's all safe for now.

Inspect your brakes regularly. (If you give your brakes the super-squeeze check before every ride, you'll never have a brake hose blow out during a panic stop.)

As far as engine cosmetics go...I'm not qualified to comment.

[Zombie Master]

As far as engine cosmetics go...I'm not qualified to comment. :lol


Have you no shame?

[Zombie Master]

How about that shifter return spring?

[gspd]

How about that shifter return spring?

The 'achilles heel' pawl spring/ What a POS.
I would DEFINITELY do that RIGHT AWAY if it hasn't been done

[Jeff in W.C.]

Transmission was rebuilt about 10-12 years and only 10-15k miles ago. I'm not worried about the pawl spring.

[Jeff in W.C.]

My plan is to have fun with the restoration, and I want to make it more reliable in the process (e.g. replace old rubber parts, etc.). FYI, the brake system will be getting new hoses at a minimum, but I'm just wondering about the 34-year old O rings in the master cylinder and calipers. And, things will be apart, so it seems like a good time to freshen things up.

GSPD....How can you ride around with an engine looking like that. I would be ashamed.

Anyway, thanks for everyone's responses so far.

[Rob Frankham]

My comment about seals (which may well be disputed) is that I wouldn't replace them unless they are leaking or you have to disturb them to address another problem. An oil seal will last a very long time unless it gates disturbed or damaged. There is as much chance, if not more, of having a leak from a new seal as there is that an old but sound seal will suddenly start to leak. Replacing seals as a matter of preventative maintenance isn't necessarily a good move.

Rob

[melville]

My comment about seals (which may well be disputed) is that I wouldn't replace them unless they are leaking or you have to disturb them to address another problem. An oil seal will last a very long time unless it gates disturbed or damaged. There is as much chance, if not more, of having a leak from a new seal as there is that an old but sound seal will suddenly start to leak. Replacing seals as a matter of preventative maintenance isn't necessarily a good move.

Rob

Similar--the likely 43 year old rear main seal on my /7 is not leaking even after sitting for over 30 years before getting fired up this year.