1975 BMW R90/6 - Rocinante

ridesolo

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Several months ago I was talking w/ a friend who told me he had an old airhead that has been sitting for a long time and his wife had been bugging him to get it out of the garage. He and his wife are semi-retired and travel back and forth between TX and Ohio on a pretty regular basis as he winds down the obligations of his local law practice. It took time to coordinate his time in town and decent weather but we finally got together last Sunday. He said it hadn't been ridden since they moved from Cincinnati to their house here and was only started once or twice since. They bought the house in 1989 so it's been sitting since then. He bought it from the original owner in 1984 and the original owner purchased it new in December 1974. The original owner, Fritz, seemed to take loving care of it as from the time it was new it was serviced at a Cincinnati area dealership every 5,000 miles through 35,000 miles in July 1984. The odometer now reads 41,533 miles. (I'd be very tempted to take it to a dealership when it rolls up 45,000 just to see their reaction.)

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It had a Wixom tail trunk and panniers and massive Vetter-style fairing w/ an AM/FM/Cassette radio and speakers. I don't plan to put the tail trunk and rack back on but I will use the panniers.

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It also included an R90S fairing and mounting hardware that I will use.

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There was a box full of other goodies that included this set of unique exhaust header heat guards that I'll clean up and mount if for no other reason than I've never seen any like them before.

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Other goodies include this box for extra light bulbs, a flat handelbar, Progressive fork springs, extra mirrors, and shorter cables for use w/ the lower bar. The complete original tool kit and roll bag and the rebuildable hand tire pump were there as well.

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The big fork mounted fairing will not be going back on. Functional and utilitarian for sure but it's heavy and ugly! I've never seen one made by Greater Hemispheres, Co. before but there's a sticker saying it was made by GH for BMW so it must have been a dealer-installed accessory.

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A shot of where (and how) it lived for over 30 years:

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Here is a shot of the potential that's there after just a few minutes of clean-up and half-assed polishing:

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I'll post a few more dirty bike pix in the next post as well as a general description of my plans for it.
 
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The small amount of time I spent cleaning today was very encouraging and as of now I don't plan to paint anything except for brackets and small parts. Everything else will just be cleaned up as much as possible and just left in a semi-original cosmetic state.

OK, a few more pix:

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The plan is to complete it in three (or four) phases:

PHASE 1: Clean it up, clean and rebuild the carbs, replace the oil/filter, replace the battery, and get it to crank and, hopefully, start. Clean out the gas tank and rebuild the petcocks. Replace seals and gaskets as necessary, replace the Sackcrete tires and make it safe to test ride and get it sorted out. At this point my intent is to ride it enough to determine if I want to keep it or find a buyer.

PHASE B: If I decide to keep it the next phase will be to install the Progressive springs and replace the fork oil (and fork seals if warranted) and put on the S fairing. I will probably also replace the rear springs/shocks, do a big brake conversion on the front, and put on bar-end mirrors. At the end of PHASE B the front end should look something like this:

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PHASE III: In this phase it will decend into being an "old man bike" by replacing the seat w/ a police/solo seat I'll also consider breakerless ignition and a higher capacity stator. My intent for the final look of the back half is something along this line: (No, not the color, just the general configuration.)

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PHASE FOUR: This one is very unsure and may never happen but if I happened to come across a sidecar for the right price, maybe....
 
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Hello
This is an "old man bike" for me ;)
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The seat conversion would be OK, but changing the color from classic black to brown? :)
Not my cup of tea ;) but it is your bike ofcourse.

Nevertheless very handsome motorcycle :D
 
I like the dressed up look, but have stripped mine back to stock config for day to day riding.
 

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This is an "old man bike" for me ;)

The seat conversion would be OK, but changing the color from classic black to brown? :)
Not my cup of tea ;) but it is your bike ofcourse.

Nevertheless very handsome motorcycle :D
Well I spoze old man bike is a relative term. To some anything older than a 2010 might be an old man bike.
The color brown has a place in the world... but not on any motorcycle (or other vehicle) I own. (On second thought, years ago there was an old brown Ford Escort wagon named RB (for Rust Bucket) that expired from a broken timing belt and bent valves...)
 
@Tim, are those handlebars on yours from an S? A flat, drag bar type of thing was included in the box of stuff I got but I don't know if I'll use them because they are very narrow. I got them cleaned up and they are a genuine BMW item. The stock bars on it now feel pretty good to me but I don't think they are going to fit well w/ that fairing.
 
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I try to remember to take pictures whenever I'm working on the thing; pix tell the story here. I got a few minutes in the shop this afternoon and got a couple things done.

This thing is frikkin dirty! For the most part, though, when I rub and buff much/most of the schmootz and rust spots clean up. This is the left muffler along w/ some of the left side:

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Here's a pix of the right muffler after a few minutes of cleaning:

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It isn't perfect and needs more work, which it will get once it's removed, but jeez what a mess. Yeah, I've seen worse on machines that were "stored" outdoors, but it's pretty grody. This really reminds me of the necessity of putting a cover on any machine that's going to be stored. I've heard complaints about covers holding in humidity/moisture, but if you live in an area with higher humidity, putting DampRid under there should help... just remember to empty the water out every once in a while and replace it when the crystals are gone. I have no idea how clean or dirty this old girl was when parked 30+ years ago, but I'll bet it would be far cleaner and less rusty now if it had been under a cover. This is especially important if your storage area is also used for wood working. I'm sure @Hurco550 can tell you about the sawdust that's still on his CB350 that spent the winter in my shop. (Yeah, Levi, I should have thrown a cover over it! Sorry!)

For the moment my plan is to pull off parts and clean them up and them put them into storage until it's time to reassemble. Today I took off the crash bar and saw that reassembly will need to include a better way to mount the Fiam horns and their relay. Maybe they weren't mounted and wired "wrong" but not the way I'd have done it. I guess that's part of making it your own, isn't it?

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I pulled out the "deader than dead" battery and hooked up a little jump start unit and the lights, horns, and the left turn signals worked but the starter only clicked. Tomorrow I'll pull the plugs and put in some oil or WD and the jump starter will have a full charge. Fingers crossed.
 
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That clock is worth a chunk if you decide not to keep it on the dash and want something to sell to buy parts, if that's the case. BMW bars are 22mm, so make sure you have the measurement. Flanders makes the best replacements, imo. I ran their Euro low bar for years. Looks like a great bike. At 41k, it's just breaking in. It's great to have at least one bike be able to outlive us. LOL
 
Thanx, Eric. The clock and voltmeter will go into the S fairing when I mount it. I measured the bars and they are 22mm. There's a BMW part number stamped into one end. Between the clock, the S fairing, the pristine tool kit, the low miles w/ maintenance records, and a couple of the other pieces that were included the thing was well worth what I paid for it. I had a price I wanted to pay and would have gone up another $1k if necessary, but I got it for what I wanted to give.
 
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HEE HEE HEE!..... "Sackcrete tires".... I love it! Seems to have been a popular tire brand on many older bikes! LOVE IT!
 
HEE HEE HEE!..... "Sackcrete tires".... I love it! Seems to have been a popular tire brand on many older bikes! LOVE IT!
The things are pretty hard, they'd be the envy of Fred Flintstone.

I sat and watched YouTube vids on carb rebuilding last night. It doesn't seem like the Bings are too complicated, as long as none of the brass has seized to the aluminum it'll be straight forward. The bike had been to the dealer every 5,000 miles right up until 6,000 miles ago so I hope the things have been apart at least once since 1975! BUT it's been siting for over 30 years so who knows what's growing in there? The gas tank smells like a combination of unicorn vomit and dragon piss. Haven't even gotten into that mess yet.
 
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The things are pretty hard, they'd be the envy of Fred Flintstone.

I sat and watched YouTube vids on carb rebuilding last night. It doesn't seem like the Bings are too complicated, as long as none of the brass has seized to the aluminum it'll be straight forward. The bike had been to the dealer every 5,000 miles right up until 6,000 miles ago so I hope the things have been apart at least once since 1975! BUT it's been siting for over 30 years wo who knows what's growing in there? The gas tank smells like a combination of unicorn vomit and dragon piss. Haven't even gotten into that mess yet.
One thing to keep an eye on with the Bings is the enricher (similar to choke) circuit when reassembling. It is possible to install them 180 degrees out of the proper placement, which would cause issues. There is a little center punch mark on the pivot shaft that either points towards the top or bottom (or maybe front or back) don't remember, but it is in the service manual that I need to get to you.

Also, you'll likely want to just go ahead an replace the floats while you are in there. They are made of foam, but eventually they saturate with gas or take on the liquid which makes them heavy, not a good look for a float.... They may look to be in great shape but will likely not do their job anymore.

The tops of those carbs also take a nice polish for what its worth. Stop by and grab my ultra sonic cleaner or homemade hot tank any time you want. The exhaust wrench too! Super happy that you got this thing, and that it "got you".
 
One thing to keep an eye on with the Bings is the enricher (similar to choke) circuit when reassembling. It is possible to install them 180 degrees out of the proper placement, which would cause issues. There is a little center punch mark on the pivot shaft that either points towards the top or bottom (or maybe front or back) don't remember, but it is in the service manual that I need to get to you.

Also, you'll likely want to just go ahead an replace the floats while you are in there. They are made of foam, but eventually they saturate with gas or take on the liquid which makes them heavy, not a good look for a float.... They may look to be in great shape but will likely not do their job anymore.

The tops of those carbs also take a nice polish for what its worth. Stop by and grab my ultra sonic cleaner or homemade hot tank any time you want. The exhaust wrench too! Super happy that you got this thing, and that it "got you".
I'm going to try using the ultrasonic cleaner I have. I THINK it's big enough for one carb body. If it's not i'll use yours. I'll watch the enritcher. The vids I watched were so thorough that the guy ended up having to make a part 1 and 2, both in the 45 minute length range. learned all kinds of good stuff and then watched another decent one and learned how thorough the first one was.

I was so darn bored for so long and now that I've got the BMW, of course, I've got another project as well. Wouldn't you know it, the powers that be decided it's time to build a new front porch. Happy, happy, joy, joy. Day 1 was demo day and the first half of day two, this morning, had me using a rented jack hammer on a concrete step. Yeah, good times.
 
LOL funny how the Honey Do list gets additions the second you get a new project
Yeah, we've been putting it off for years for various reasons, guess we aren't putting it off any more. It's ok, I guess, Rocinante will take a whole bunch longer than the porch will.
 
"The gas tank smells like a combination of unicorn vomit and dragon piss."

VERY DESCRIPTIVE of That Odor that we all know so well. Something that also smells identical is California Tap-Water, which would explain a few things.
 
In my moaning and crying about how dirty the thing is I forgot to mention that the front spokes seem to have molded or something, it looks like they have a green tinge to them. @Hurco550 said he thought maybe that wouldn't clean up well and after a few minutes of rub and scrub it looks like he may be right. I could replace them and would also consider giving them a good cleaning in something caustic and then paint them black. In all honesty I'm not much of a traditionalist and don't care for spoke wheels. I'm not fond of cleaning the things. I'd much rather build the thing up w/ Lesters or BMW Snowflakes but since I haven't won the lottery and believe it would be best if I don't try bank robbery I guess I have to do something w/ the spokes. Does anybody out there have experience w/ the dreaded "green spoke disease?"

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After we picked it up we also noticed that the mufflers on it are different, one appears to be OEM and the other an aftermarket.

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And when I was cleaning the OEM on the right side it looks like maybe there's some rot out beginning. I don't know if this pix shows it well enough or not. Any opinions?

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And finally... here's a better shot of the aforementioned relay for the Fiam horns.

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STILL a gorgeous bike. Earned her patina. Painted spokes seem like they'd be easier to take care of? I'm sure if a person has to, they can true them later as needed....?
So I Googled "Metal Turning Green" and they're suggesting bronze or copper. (?) In my old days as a Kitchen Officer, I learned that if you rub on ketchup (or mustard? I forget) that it wipes the green right off, like nothing. Worth a try.
 
In my old days as a Kitchen Officer, I learned that if you rub on ketchup (or mustard? I forget) that it wipes the green right off, like nothing. Worth a try.
That's probably the vinegar in the ketchup, seems like I've heard that, or maybe it's the acid in the tomatoes? I'll try a few things and see what works, if anything. Knowing me, though, if the things don't clean up I'll take the wheel(s) down and clean/paint or replace the spokes. I'm not going to try and paint them with everything together.
 
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