BMW R65 Motorcycles

mshriner · 06-25-2006, 09:23 PM

Looking for a starter motorcycle and came across and ad for a 1980 R65 BMW - Seller is offering it for $800 with a plug that fouls so the bike runs on 1 cylinder. My thinking is that it is similiar aircooled technology I can probably figure out how to fix it but wanted some advice? Could this be a carb issue?

Seller's description in answer to an email.

"Thanks for expressing interest in the bike!
I bought it from an older gentleman- 72 years young- in Moraga months ago... it rode home to San Leandro no problemo. Next time I rode it, I noticed that it started running on 1 cylinder. My guess is that the plug on the right side keeps fouling. It starts and runs but only for short intervals. It is a gorgeous bike- no dents- cosmetically it is a beauty. It just needs work to run as it should and I am not interested in it anymore. Hence the low price.
Thanks- check the pix- and I don't know the mileage, since the odometer is not working- it looks like for it's age that the mileage is lower than the average 26 year old motorcycle- and I did purchase it from a rather older enthusiast."

jdlowery · 06-25-2006, 10:36 PM

Sounds like it could be a find or maybe an expensive project. Try to find out how mechanically inclined was the last owner. Maybe a tune-up will solve the problem. On the other hand, could be something more serious like valve recession. In any case, if you could check it out personally you may find the answer. Check the valves and make sure they are set correctly. Check the plug wires on the side that doesn't run well. Check the connection to the coils. Coils usually don't go bad but it could be the problem. Also, on the '80 models the coils need to be grounded to the frame. A lot of these bikes have broken coil mounts that makes for poor grounding. A welder will fix that for a few dollars.

R65s are nice little bikes. Let us know how things work.

1967 R50/2 · 06-26-2006, 03:45 AM

For $800 bucks, I don't see how you can lose. Even if you don't get it running, you can probably part the bike out on ebay for a profit.

mshriner · 06-26-2006, 04:12 AM

Thanks guys. It is actually the guys wife selling it. She found it and was trying to get him into riding and on his second ride the bike stopped on him and he is not a project guy and just shut it back in the garage. I like the bmw bikes enough that even if it is a worst case scenario and needs more work I am still interested. Heck, I'm from the Porsche side of the board for every $2/3 in I only expect to get one back out. Thanks again, I will let you know how it turns out.

Matt

mshriner · 06-26-2006, 05:37 AM

Bit more information: The seller thinks that the "plug on the right side fouls. It may be a stuck float in the carburetor. " I think your plug wire / grounding theory makes more sense?

Matt

Joeaksa · 06-26-2006, 09:06 AM

Singpilot (Michael) just bought a R80 and loves it. The old BMW technology is very easy to work with. Even if you had to put new rings in the puppy its not difficult with everything out in the open.

Buy it and enjoy!

stevepaa · 06-26-2006, 09:08 AM

so where did you find the ad? thanks

jdlowery · 06-26-2006, 10:07 AM

Quote:

Originally posted by mshriner
Bit more information: The seller thinks that the "plug on the right side fouls. It may be a stuck float in the carburetor. " I think your plug wire / grounding theory makes more sense?

Matt

Floats are cheap. If you change them also check the float needle valve. Sometimes the rubber tip wears down and can cause flooding. If you're getting a good price you really can't go wrong.

Joeaksa · 06-26-2006, 10:32 AM

Quick check is to pull the right hand spark plug. Sooty black or gummy black? Also check in the same side muffler.

Sooty is too much fuel, gummy is oil. Sooty is carb/needle valve and oil means its coming from the engine, usually rings. Neither is really hard to fix but if I had my choice the carb is a lot easier.

Also, turn the fuel petcocks on and wait a minute. Do you see any fuel dripping from the carbs? This happens at times and can be a sigh of a bad float needle valve which can lead to fouling.

singpilot · 06-26-2006, 12:01 PM

I DID just buy an '80 R65. I do love it. I got mine with a bad clutch, and the only surprise was the price of parts from BMW. The '79 and the '80 are two orphan years, nothing from other years fits these, so parts are expensive. Clutch pack, including drum and pressure plate was $560.

The Bing (constant depression) carbs can be finicky until you get them set up right, but once set, they run well. Like Joe said, you need to figure out what is fouling the plug. Oil, gas, or no spark. Be careful checking the spark on these, doing it incorrectly will fry the coil or fry you, either way it's a trip to the BMW parts counter, and you'll not enjoy that.

The service manual has all the procedures. Once running, it is a sweetheart. I found a set of city hard bags and mounts for this one, so it makes a great commuter. That's on SoCal freeways (80 MPH is normal).

I am looking for a second caliper and rotor for the front (the forks already have the mounts), as the only drawback I can see is the single front rotor. I am spoiled by the great brakes on my other bikes, and that is my only complaint on this one. They are adequate, but not much left for a panic stop.

The speedo and tach are notoriously fragile. My tripmeter is stripped, and I have the parts on order. I am watching evil bay for a cheap set.

Have fun, you'll love it.

Joeaksa · 06-26-2006, 12:25 PM

Michael,

Believe that most R80's were sold in Europe, so that there is not a lot of them here. Also believe that the frame and running gear is the same as the R100 so those parts should be available everywhere. Same with the R65.

Try Bobs BMW in the DC area for parts. They ship worldwide and can get almost everything.

http://www.bobsbmw.com/catalog/index.html

For the brake parts you might find them on Ebay.

JoeA

jdlowery · 06-26-2006, 04:38 PM

Quote:

Originally posted by singpilot
I am looking for a second caliper and rotor for the front (the forks already have the mounts), as the only drawback I can see is the single front rotor. I am spoiled by the great brakes on my other bikes, and that is my only complaint on this one. They are adequate, but not much left for a panic stop.

You'll also need to change the brake reservoir when you go to dual disc.

mshriner · 06-26-2006, 10:08 PM

Hey guys. Thanks for all the advice. I bought the bike for $800! It is pretty rough looking but fairly complete. It is getting spark, The right side plug seems to be sooty which from what you guys are saying probably means the carbs. The valves are also noisy on the right side? Which I hope means adjustment not replacement? Plus, when tilting the bike to wrestle it on and off of a pick up truck the carbs leak gas everywhere. Does that support checking the floats and needle valves?

The bike had sat for five years prior to being bought by the last owner. It drove home well but then began having problems the next time he started it up. A mechanic told him that he should have emptied the tank before starting it because the old gas / varnish may have gummed up the fuel lines/ carbs. Where should I start? Empty the tank now? Then check the float and needle valves? Actually, I am taking tommorow as a vacation day to clean up my garage prior to digging in.

Matt

Joeaksa · 06-27-2006, 05:08 AM

How good a mechanic are you? If you work on your 911 then this is easy. Get a maintenance manual or look in the riders handbook as it has most of this inside.

Pop the valve covers off and check the valve adjustment while its cold. Put them back on and start the bike up and get it warm, then change the oil. While here do a compression check to see what you have.

Drain the fuel if there is any question about it and refill as needed. Keep the petcock turned off and remove the bottoms of each carb. Look in the float bowl and see how much crap is down there. Also one at a time check the workings of the needle and seat and check the fuel level, especially on the right side.

After doing this you should have a good idea of what you have and what needs correcting.

As a new BMW owner, one thing that many people damage is the bolt that holds the negative battery cable to the gearbox. The correct bolt is hollow, to provide a vent to the gearbox. Many people overtighten this bolt and break it. Be careful with this! Also do not use the wrench supplied in the tool kit to remove the big finned exhaust nut. Get a aftermarket one that wraps around and inside the fins.

mshriner · 06-27-2006, 06:39 AM

I do work on my 73 911 and love it. I've got a Clymer's manual to start. Thanks for the advice!

Don Ro · 06-27-2006, 10:53 AM

Good stuff, Joe.
.
Also, if it has inline fuel filters, replace them...if not, add them prior to running even fresh fuel to the carbs.

Check tank for rust/crap.
.
Good luck - sounds like a great project bike.

Joeaksa · 06-27-2006, 11:04 AM

Don brings up a very good point. Open the fuel tank filler and look inside. Tell us what you see? It should be red colored primer I believe and anything else means that its either rusted or been repaired.

Fuel tanks on any motorcycle do rust if not taken care of but you can find them used on Ebay if its bad.

Flatbutt1 · 06-27-2006, 11:25 AM

As far as the valves go, they tend to be noisy on the airheads so do a careful adjustment. Remember a loose valve is a happier valve.

mshriner · 06-27-2006, 08:49 PM

Joe/Don/Jim and company, the tank looks okay. I'm not seeing any rust. The float bowls are clean no gunk / crud? The bracket holding the coil for the right side cylinder is broken and hanging by a thread. There still is a solid bracket attached to the frame and a ground wire that looks solid I sanded and reattached the ground but will have to buy the part to attach the coil, I looked at the valves and clearances on the RHS but realized I couldn't rotate the tires to get to top dead center until I either bought or borrowed a motorcycle stand so that will have to wait. (Harbor Freight here I come...)I also fixed the gap on the spark plug on the right side. Reconnected the choke cable to the right hand cylinder. Then I had to wait while a trickle charger recharged the battery. It fires up nicely everytime....but sounds pretty bad, it is still definitely still misfiring but both cylinders may be operating???

According to Clymers I still need to eliminate:
*plug wires - (sounds a bit like a car I had that would miss when the plugs wires needed replacing? - may be wishful thinking)
*(I was planning to cross spark plugs and gap off the list bc I do get *spark and plugs are now properly gapped.)
*air filter looks fine to me
*How do I check for "faulty contact breaker points"
*Carbs? Not sure how to tell if they are improperly adjusted
*Ignitiion timing
*valve timing
*poor compression - I'm going to borrow or buy one over the weekend.

Then I move on to my bigger fears:
"slapping or rattling noise" - piston slap
"persistant knocking and vibration occuring every crankshaft rotation - excessive main bearing clearance" ??

I am too much of a rookie to isolate and describe the sound. Just sounds bad. Like the guy in the movie "Sideways" - (mmm, good - for every wine he tastes - -are you chewing gum!) Anyway, on the positive side it sure is easier to get to things than on the car.

Overall, the frame has some light surface rust, the tank looks like it was painted with a rattle can, and I think somebody may have bondo'ed some dents in the tank but so far everything looks manageable cosmetically. As soon as I find the battery for the camera I will post some pictures. Thanks!

East Bay Folks: Where would you buy motorcycle parts locally.

Matt

Joeaksa · 06-28-2006, 12:13 PM

Matt,

Looks good and would keep plugging away at it. Check the compression and if that looks good would focus on getting spark and fuel to the right cylinder all the time.

Get a manual, disconnect the battery and remove the front cover. The points are there, running off of the crank. DO NOT try to ever turn the engine over using the nut/bolt on the end of the crank by the points, as it will break then you are screwed. Use the rear wheel with it in 2/3rd gear.

Once you get the rest sorted out you may be ahead to find someone locally to help you with the carbs and to identify the engine sound.

Also, if anyone is looking for a good used BMW, this one was just posted to a BMW list I am on. '80's R80, with a RS fairing and looks fairly good. Located on the East Coast and selling for $3000. Sounds like a good deal but who knows.

http://homepage.mac.com/buchzi/PhotoAlbum13.html
soledoctor@gmail.com