R75/5 Help

[ebueker]

I just bought a 1972 R75/5 with about 20,000 miles on the speedo. The bike has been stored for several years. Cosemtically it looks good for a bike that old and unmaintained. Besides changing the engine oil, what should I do before turning the engine over? Someone told me to remove the plugs and soak the cylinders with WD-40.

Any help will be appreciated.

[StevesGarage]

For just turning the engine over (i.e., not running it), just a little motor oil through the spark plug holes should be o.k. We're talking maybe two tablespoons. Include a little Mystery oil or other oil additive if you want to be fancy.

WD-40 seems a little too thin. I also don't like the idea of mixing it with clean oil.

It would be well worth the time to pull the oil pan and check for gunk. Also check the sump screen and clean it. Watch the torque on the pan bolts when you reinstall!!!!

There is a lot more to do before you actually run it and ride it. Plan on both a "Minor" and a "Major" maintenance/inspection. (This was tossed around in another thread, but I forget which one... Might have been the one about steering head bearings.) In short, you have no idea what was done when and by whom. It is tempting to just change oil, fire it up and go. Bad idea.

--Steve

[AnnapolisAirhead]

Congrats!

I'd pull the carbs and rebuild them if its been sitting more than a year. Change the fuel line, air filter. Remove the tank and empty it into a container where you can see what falls out. Remove the petcocks and replace the filter screens (2 per petcock, one large, one tiny).

Next, disconnect the battery (at negative terminal), remove the front cover and clean all the electric connections, lightly grease wit di-electric grease. Do the same to the starter relay (left side of frame under tank). You may also want to remove the engine top cover, pull the starter wires off, sand them, di-electric grease them and reconnect.

While the bike is stone cold, remove the valve covers. Run a static timing of the bike, then set the valves. While timing it, you'll find out if the engine will turn over or not (most likely it will). I use Marvel Mystery oil in the sparkie holes, then change the oil after its gotten good and warm. If you run it for more than 3 or 4 minutes, put a box fan in front of it to cool the cylinders.

That should put you in pretty good shape and these are things you'll probably want to do anyway so I'd recommend doing it now.

How long was the bike sitting?
Button it up, connect the battery and give it whirl. Mine sat for 8+ years and shot sunflower seeds out the exhaust when I started them...

[ebueker]

The bike has been sitting for several years, don't know exactly how long. It was part of a collection of bikes and cars from an estate auction. Well I wanted a "project bike" and it sounds like I've got one. Any good sources for parts for bikes this old? Like the screens, etc? Thanks for the info.

[tvrla]

After sitting for several years, the carbon on the piston tops and heads falls off. I'm sure that's the source of the scoring you see in cylinders quite often.

So before oiling the cylinder, vacuum that sucker out! Do what you can to ensure all that garbage is out of there.

Before starting the first time, put in fifth gear and rotate the rear wheel for five minutes or so. This will force lube into everyplace that needs it - trans, final drive and engine. Then once the engine is first started, put it in gear (on center stand) and run it for a while that way - this will ensure the trans is fully lubed - there are some bearings in the trans that need a LOT of splashing to get fully lubed.

[StevesGarage]

I like tvrla's advice. I'm in the process of bringing one back. Wished I'd thought of vacumming it out. Oh well, next time!

I've used several different sources for parts. Hucky's is my current favorite, and his site has decent pictures. www.bmwhucky.com But I have also done a lot of business with Bench Mark Works http://benchmarkworks.com and Capital Cycle www.capitalcycle.com There are several others with good reputaions on the west coast, but I have never used them. (I'm Chicago area) If you have a local BMW dealer, they may be able to help with some stuff. Some shops know the older stuff, others are completely lost.

Do you know BMW's? I'd suggest getting a copy of the Clymer BMW repair book. It has a maintenance chapter that will walk you through just about everything you need to check. The owners manual will also guide you through a pretty complete maintenance check. (Although, the repro manual costs as much as the Clymer book!) Also , Duane Ausherman's site has a ton of info (www.w6rec.com/duane/bmw/index.htm). You will learn a lot by just going through his vocabulary section. Bench Mark Works also has some tech info that is very helpful. (I just tried his technique for removing a fork lock without drilling. VERY slick!)

And of course, ask here. But always confirm everything you read here. I've read some good and bad advice on this forum... Typo's don't help either. Recently one guy sounded like he was recommending a gasket sealant as a spline lube.

--Steve

[TomBarnhart]

All of the above PLUS: Check the charging system, relays, etc--clean the contacts. Also check the brake system (what little there is). New fluid and then check for leaks and bad hoses. The under-seat master cylinder is notorious for leaking and corroding the frame rail. Good luck if it is bad, parts are very expensive, as well as the brake line hose. New brakes can cost up to $500 in parts.

[StevesGarage]

Fortunately you have drum brakes. No reservoir or lines to worry about.

[DennisDarrow]

Just a thought or two........first of all you have an R75/5...........It has a kick start.........You can pull the plugs and kick it over quite a few times to get the oil circulating and at the same time get the oil/solvent worked into the piston.

Draining the fluids: gas, transmission, drive shaft, crankcase, and final drive are great to do right now. Take the bowls off of the carbs after you put in fresh gas and let it drain through the fuel lines into a clear container. Check for contaminants.........If so......yes, do take off the petcocks and clean/flush the tank; but no need to replace the screens just clean em up.........

You have drum brakes so dont worry about any master cylinder under the tank. It is worthwhile to really check the actuation of the brake levers down on the drum. Yes, grease the arms on the interior of the drum but make sure the arms are actuating equally and together. Often times the front will be out of adjustment and you will only get half the braking force available.

For me, I would adjust the valves after torqueing the heads and then check the timing with a static light. Hopefully it is already timed and ready to rock and roll........hope it starts at that point............

Yes, do figure out how to replace the diaghrams, and o rings on the jets.......do that before you start perhaps; but as soon as you can.........learn how to set the idle by ear syncing the throttle cable, idle screw, and air screw.......

on and on............Good luck.......God bless............Dennis

[ebueker]

Thanks for all the advice. I have the Clymers Manual and have been reading it, but didn't know what all I needed to do before trying to start it. You all have given me food for thought and some direction to go and I appreciate it. I would never have thought to rotate the rear wheel or use the kick start to get the lube circulating. I ride an 06 R1200RT so I have little experience with BMRs other than other than changing oil, tires, and adding lights, etc.