What have I got myself into - 1972 R60/5

[texasmule]

A co-worker of my wife has a 1972 R60/5 that's been sitting in his garage for quite some time. Since I have worked on BMW's for years (no airheads though) he asked my wife if I could "finish" his project.

He had the engine rebuilt by a reputable builder, had the paint done (very well), new tires, wheels look good, frame painted, etc.

All that's left is finish the wiring, adjust the carbs, and Bob's your uncle, she should run (famous last words).

Well I agreed to take it on, and quoted the hippocratic oath (First do no harm) that I wouldn't make it any worse than when I received it.

Having only owned MANY oilhead/hexheads I have no real experience with airheads, other than a pretty decent aptitude with mechanics (and 40 years of working on motorcycles/cars). I figured with some help from the collective wisdom here, and the MOA, I might, (just might) be able to get the bike running sometime before summer.

In order of magnitude of problems that I've seen in the 24 hours I've had the bike.

1. No petcocks. Which (and where) do I obtain petcocks for an R60/5?

2. The rear wheel was assembled, but the tire is rubbing on the right side swing arm. There's 2-3 inches on the left, none on the right. I'm going to take the axle apart, but I don't see how I can shift the wheel to the left and not expose the brake shoes.

3. Wiring is, well let's just say I may have to start from scratch. I have a very decent colored wiring diagram from the web, AND it's not an R1200RT so the wiring is pretty straight forward, BUT there are two wires that I can't for the life of me figure out where they go. They are GR/BK, and GR/BR and I can't find them anywhere on the wiring diagram.

Also, did 1972 R60's come with seat locks. This one doesn't have one and I can't seem to figure out how the seat stays down without it?

I'm sure I'll have a few more questions 3 but thought I'd start with these first.

Any help would be appreciated guys. :freaky

P.S. I thought most (if not all) airheads had a choke lever. This bike has choke cables, but no choke lever. Is this another thing that's missing?

 

[20774]

Couple of answers off the top of my head:

Rear tire: my guess is that the tire is too wide for the bike. Nominally it should be a 4.00x18 tire. I bet he has a 120/90 or even wider in there. There is a part that can be used to space the tire to the rider's left, but you have to get into the bowels of the bearings. I'd ditch the rear tire for the right size...it's better for handling anyway. People think a wider tire is better...it's not.

Choke: those are slide carbs, and it appears there is a black button on the side. This would be a tickler meaning that you push it down for a count of 3 or 4 in order to flood the carb. This is a holdover from the /2 days.

Petcocks: Plenty of places to buy petcocks. BMW Hucky's, Vech at Benchmark Works, Bob's BMW, Max BMW. If you call Max BMW, ask for Rusty...he knows his Airheads.

I'm sure others will chime in.

 

[darrylri]

The petcocks are Karcoma brand. The bike originally came with straight through petcocks, but the only ones available now are 90 degree. They'll work fine anyway.

Yes, you need a seat lock. It fits in the round hole, in the plate that is also where the grab handle mounts. Get it keyed to match the steering lock.

GR/BL should go from the starter relay to the horn and into the bucket to the circuit board.

GR/BR is either the oil pressure sender under the left cylinder to the oil pressure telltale in the bucket or from the circuit board out to the high beam flash button.

 

[happy wanderer]

Wiring question: Not sure if you mean Green Black or Grey Black but you can find some great information on Airhead wiring here: http://www.airheads.org/technical-tips-articlesmenu-98/302-wiring-color-codes

Consider joining the Airheads club. Tons of Airhead specific collective knowledge in that club.

 

[tanker4me]

Ditto on reply #1

Too fat tires will change the handling even if they fit. I tried larger tires on a R60/5, and was happy when I went back to the stock size.
BMW dealers might have the petcocks in stock, (1970-1995 are interchangeable , the barb exits down on /5) if not they can order them. Irv Seaver a local dealer here carries a lot of airhead stock. Josh Buck at Parts Haus is a source for used BMW motorcycle parts, 562-254-0452.
The R50-60/5 are tickler enriched, the R75/5 had the manual choke mounted on the left side air box cover.
According to the Clymer diagram (fused) the wire that is BR/GR is the oil pressure switch, GR/BK is one of two that go to the rear brake switch, the other of which should be GR/RD. The only thing left down there is the neutral indicator switch and its BL/BR.
Some parts are easier to find than others. I was able to get the keyed part of the seat lock from BMW.
Three Fat Tires and you shouldn't be riding!

 

[20774]

Also, be sure and look through the link in my signature line. Lots of good reference info there.

 

[88bmwjeff]

Rear tire: my guess is that the tire is too wide for the bike. Nominally it should be a 4.00x18 tire. I bet he has a 120/90 or even wider in there. There is a part that can be used to space the tire to the rider's left, but you have to get into the bowels of the bearings. I'd ditch the rear tire for the right size...it's better for handling anyway. People think a wider tire is better...it's not.

Although I have no first hand knowledge of this, others have chimed in in the past about certain parts of the bearing stack being in the wrong order which can cause the tire to rub. I could be wrong, but I do remember reading this. Hopefully others will chime in about this.

 

[lmo1131]

The petcocks are Karcoma brand. The bike originally came with straight through petcocks, but the only ones available now are 90 degree..

Actually, straight through Karcoma petcocks are still available, directly from Bing. And they fit and look better on the /5 since the fuel line drops straight to the carb.

While you have the silencers off, the lower shock mounting bolt, on the left side, should be inserted from the "inside" ... with the nut on the outboard side. Otherwise, when the muffler is on you won't be able to get the bolt out. An infrequent occurrence, but an annoyance when the time comes.

And if time is money, starting "from scratch" on a /5 wiring harness is a waste. A brand new, complete, stem to stern, wiring harness is only about $150.

 

[lmo1131]

About that rear tire.... if the tire/rim is off by 2-3 inches, then it was not properly laced. The center line of the rim is not on the same plane as the c enter line of the hub/drum assembly, it is offset. And it isn't just the rear, the front has offset too.

Old post on rear wheel offset > http://forums.bmwmoa.org/showthread.php?49078-Buchanan-spokes-R75-5-no-offset

BTW, do I see the "Continental" logo on those tires? Are they 3.25x19, and 4.00x18?

 

[shandeland]

Google Duane Asherman BMW and look at his website. Make sure that the rear axle and bearing stack is assembled correctly. Duane has a very good write up and series of photos that explain and show how it should go together and how to adjust it.

You do have a project on your hands.

Steve

 

[20774]

Lew, he indicated there was 2-3 inches on the left side from the swingarm to the tire, but it was rubbing on the right...I wouldn't think the whole wheel is offset that far...I can see that his hub closes around the brake housing so it can't be that far off. I think with the proper setup, the distance between a 4.00x18 tire and the right swingarm is only a matter of a few tenths of an inch...maybe up to one half inch. I can see the 2-3 inches on the left side. But you raise a good point...hopefully no one has mucked with the wheel-hub offset.

 

[texasmule]

Checked the tire last night....Continental 4.00X18. Appears to be the right size.

Spoke to the owner last night and he DID have the wheels re-laced. It doesn't appear there's an offset but I need to check. Been working on the wiring,

If there's no offset, he's going to need to send it off to someone to fix the problem.

Back to the wiring issues...uke1

BTW, how easy is it to take off the ignition module? Seems it would be easier to wire if I didn't have to look upside down and backwards.

 

[20774]

BTW, how easy is it to take off the ignition module? Seems it would be easier to wire if I didn't have to look upside down and backwards.

Bummer on the tire...it does sound like it was laced wrong. There are several places listed in the link in my signature line that work on wheels. Woody's is the place mentioned most often.

Ignition module? I'm assuming you're talking about the small circuit board in the top of the headlight shell. They can be removed, but... There are four tabs that come through that board holding it in place. Those tabs can only be bent and straightened so many times...then they break...now you're in trouble. There is a process of annealing those tabs to add the strength back...it takes getting the tabs cherry red with a pinpoint flame/torch...there is a method of using a battery and wire leads. With all of that, there's the potential of messing with the paint of the headlight shell. I'd keep standing on my head to work on it. If it's non-functioning, then it might have to come out.

 

[texasmule]

Curiouser and curiouser....

The wheels on an R60/5 should be 1.85" here's the measurements on the rear wheel.

and the full width...

Just a tad over 1.85" and as far as I can measure there's no offset, especially with the wide rims. The rim is as wide as the brake drum hub.

Oh BTW, the front rim measures 2.22" and 2.62" at the same measurement points.

He swears he rode the bike before the wheels were re-laced, and they're the same wheels. These can't be the original wheels so whatever bike they came off of they worked at some point.

I'll try the inner axle spacer before the wheel is sent off to Woody's.

 

[texasmule]

I know this is not much help, but at least I have photographic documentation before I start to tear into this.

Whoever put this together didn't put much moly on anything.

 

[20774]

Good catch on the splines...a good, thin dose of Honda Moly 60 paste should do the trick.

I've never known where to measure the rim width...there should be a stamp on the rim indicating it's true width.

 

[lmo1131]

The front rim is 1,85 x 19

The rear rim is 1,85 on the R60/5' it's spec'd as 2,15 x 18 on the R75/5... Why?

I wonder if the rear rim was replaced with the wider rim at some point?

 

[69zeff65]

I think a slimmer rear rim was available back then

I have two of them. One is on my early R 75/5 and the other came on a later (72) R 60 frame and components I picked up. The explanation I got from a number of different Airhead guys was the smaller displacement bikes got them. I was also told some people prefer the slimmer rim due the better handling due to the smaller foot print from the tire. I have turned down a number of offers for one of mine, I thought about lacing it onto a front hub and mounting an earles fork on one of my projects. Anyway maybe it is a combination of a backwards laced wheel and the bearings aren't properly set in place.

 

[fxray]

Curiouser and curiouser....

The wheels on an R60/5 should be 1.85" here's the measurements on the rear wheel.

and the full width...

Just a tad over 1.85" and as far as I can measure there's no offset, especially with the wide rims. The rim is as wide as the brake drum hub.

Oh BTW, the front rim measures 2.22" and 2.62" at the same measurement points.

He swears he rode the bike before the wheels were re-laced, and they're the same wheels. These can't be the original wheels so whatever bike they came off of they worked at some point.

I'll try the inner axle spacer before the wheel is sent off to Woody's.

You are not measuring the wheel correctly. The 1.85 dimension refers to the distance across the inside of the rim from one bead seat to the other.

Your caliper in the first picture shows 2.554 inches. If you subtract, 2.55-1.85=.70 inches

Dividing .70/2=.35 inches

Each side of the wheel could easily be .35 inches thick, and that rim in your picture could be the proper 1.85 inch rim.

Take a look at the diagrams on this page, for example.

Also, wheel width and offset are two different dimensions. A wide or thin wheel could have the same offset. How are you going about measuring the offset in this wheel?

Ray