1975 BMW R90/6 - Rocinante

Yep, I ordered mine at about an inch too short and ended up having to make a little standoff to get it to work. Tim ordered his right after mine with this correction.

Tim & Levi: (@Tim & @Hurco550)

Thanx for the info. I had just about decided to get the "short hose" that Matt sells and use it from the caliper up to the BMW connector higher up on the fork leg, then from there up to the MC w/ the BMW stock hose. Yes, that one is rubber rather than SS, but I figured it might be an easier part to source a replacement for if in an emergency and maybe some day down the road I could replace it w/ SS. EDIT: Got a replacement for the original, never did hear back from the other folks so forget 'em.

I kinna like the look of Matt's short hose set-up, a little more of a "buttoned up" look to my eye.


What was the cost of the Speigler hose, Tim? Matt's short hose is $40 and the long is $70.
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Of all the things that I would try to save on a bike that has been sitting as long as this one, O.G. brake lines would not be one of them. I looked for my order conf and couldnt find it from speigler, but IIRC they would be quick to send you a quote if you fill in the info that Tim gave you on their site.
Wrote to them. If their custom line is similar in price to their stock replacement R90 line they are pretty competitive. EDIT: 20 Dec 23 Have written to them TWICE now and no answer! :mad:

Yeah, I was thinking about the age of the line I have. I did a very thorough inspection of it while cleaning and was surprised at the condition it is in. BUT, even if it's been replaced sometime in the last fifty years it still would be over thirty years old so, you're right, that's something I don't wanna take chances with.
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I found the only single left caliper on eBay AND at a very good price, shipped from Italy. So Plan A is off and Plan B is on.
Hope I don't have to develop a Plan C. Just discovered the caliper is being shipped from Bucharest. Hope it isn't a boondoggle!

EDIT 15 Dec 23: Just got word that it's now in The Hague so perhaps it's really on the way. Budapest to Bucharest to The Hague since the 12th, might even arrive before the projected 26 Dec date. Who knows how long it'll take to get through US Customs though.

EDIT 20 Dec 23: The tracking now says it's left the Netherlands so it's either on a ship or an airplane; hoping for good North Atlantic weather. I'm wondering about used MC parts, especially parts from high end bikes, coming out of Budapest. To me it brings to mind images of containers full of stolen cars and motorcycles shipped from various places to Eastern Europe where they are stripped and parts put up for sale.

EDIT 24 Dec 23: I got a msg saying it's in the US. USPS says that tracking number is in Chicago

EDIT 30 Dec 23: Now somewhere between Chicago & Cleveland.

EDIT 2 Jan 24: It arrived and is in very nice condition. Sometimes things all work out.
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Nice weather today and I got to spend a pleasant afternoon. I got the left cylinder buttoned up and torqued and valves adjusted. I couldn't resist and decided to clean up the rear wheel and put it in place. I probably should have cleaned up the drive housing first, but i'll get that done as I work my way around the thing. I like the Lester on there, it looks pretty good to this "don't like cleaning spokes" guy.

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I got the right cylinder off and it looked pretty good, at least it didn't have old gasoline goo in it, but there was an old spider's nest! One of the valves must have been open, but would the spider have come in through the intake or exhaust?

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A couple more hours spent before Mrs Ridesolo needed some help in the house, and my feet were cold anyway.

I got the right cylinder buttoned back up and the valves adjusted. Yep, there are many things that are easy to do on an airhead. While I can disassemble, repair, and reassemble things successfully, I usually don't think of myself as much of an auto or cycle mechanic. Oil change? Sure. Brake pads? Yup. Replace a starter? Sure, as long as it's not on a Tundra, I'll NEVER do that again! But the airhead isn't all that difficult to wrench on and there's lots of help available online and in print.
If you have an interest in one of these and find a decent deal, jump in with both feet! (Yeah, some of the parts are a little more pricey; @Hurco550 calls it "The BMW Tax."


Slowly getting more of the dirt, oil and rust off of things as well. This foot peg mount was as bad as the one on the other side.


The R90X Designs kit for the front brake was ordered today. I have the disc, the caliper is on the way, and now the kit is as well so the thing is going to have something closer to modern bakes: four piston radial caliper and a 320mm floating disc.
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Spent some time scrubbing away at chrome for a while just to do something different. It cleaned up pretty well but there are some spots where the chrome is gone. If I were doing a complete restoration I guess a re-chrome would be in order but leaving it as-is will fit w/ the survivor theme. Spoze I could paint or powder coat but leaving it as is stays w/ the plan to make a good survivor.





It's difficult to get good pix of shiny stuff so I think it's safe to say it's better than the picture shows but not nearly good-as-new.

I sat there contemplating the seat itself and wished I had more skills and experience in fabrication. Guess I should say I'd like to have ANY skills and experience in fabrication! I've been thinking right along that I'd like to fit this w/ a solo seat. The things are available for a price and it wouldn't break the budget to just buy one but I'm not really fond of the shape of the Police Seat. If that's what I end up with that's what it'll be. What I'd like to have, though, is something along the shape, size, and profile of the original seat, just shorter. I guess there's be some way to get another original, remove the cover and foam, cut and reshape the pan into the right shape, re-sculpt the foam into shape, and then have an upholsterer make a new cover. AND THEN, if I'm lucky, it might even look good. Oh well...



Just downloaded this screen editor and my lack of experience shows, but the idea would be to remove what's between the two lines and then mate it all back together in some form of cohesiveness.

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Fortunately daylight and a new day bring a bit of clarity to thought. No, I won't be carving up the original seat. I'd consider surgery on a tired and beat up OE or replace this one w/ a nicer one if I acquire one. At this point I wouldn't even replace the upholstery on this one but I think i saw a replacement for the trim strip that goes around the bottom. It's too bad, this one is fairly acceptable except for one spot at the back that's pretty much destroyed. BUT at over $120 for a replacement? Nope!
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The parts from R90X for the big brake conversion arrived today. It all looks pretty good and complete.


As of now the caliper is still tied up in Customs at Chicago O'Hare Airport. No hurry at this time anyway, I need to pull the forks apart, replace the oil, and put in the Progressive springs. I'll check to see if they need a rebuild kit while I've got things opened up.
Oh yeah... and added a couple of sturdy eyes to the back of the work table to get the front wheel up for fork work.


I'll eventually have to get it off the center stand so I can pull the oil pan to replace that gasket but I guess I'll get there when i get there.
The inevitable happened and I found something way too tight and stubborn. The cover/cap/nut thing that holds the swivel caliper pin in place took some heat from the shop heat gun and a very long breaker bar.


And what I found didn't make me happy; somebody had obviously abused the thing, probably used the wrong kind of wrench and then tightened it way too much. In addition the brake pads were very unevenly worn which tells me the caliper hadn't been properly adjusted to be centered the last time pads were changed and the pinch bolts for the front axle were way too tight as well. Probably whoever last changed the tire and brake pads didn't have a torque wrench. Hope I don't run into too much more of this!


I may have to replace that, but I'll try to dress it up w/ a file first. $22.95 from B2V so it's not as bad as I expected it to be.

Since I was taking off the front wheel I couldn't resist messing w/ the new wheel, R90X parts, and the big disc. I've got more cleaning to do so things are just stuck on there and not torqued.

Disc adapter:


And disc:


The thing ought to stop a bit easier and faster.
Not much done in the last couple of days, other obligations took away from shop time. However, the new brake caliper arrived and appears to be in excellent condition. The brake pads were close to being "like new," and are OEM Brembos (dated 2013) but I'm sure there's enough brake fluid on them to make them trash anyway. They are small, though, so I thought I'd clean them up as much as possible and stash them in w/ the tool kit to have handy in an emergency. There is a new set of carbon ceramic pads on the way. The new banjo bolt/bleeder combo is strange to me but ought to work as advertised.



This four-pot caliper has four separate brake pads rather than two so you don't have to remove the caliper to change pads. Pull out the two black pins, remove the spring keepers, and you top load 'em like slices of bread in and out of a toaster.

I'm not going to do the required surgery for the mount on the fork slider until I pull the forks to change the oil and put in the Progressive springs. BUT that's coming soon.
More cleaning today, endless cleaning, it seems like. If I could go back and do it over I'd spend at least five times longer w/ the high pressure spray I put it through at the car wash back in June '22. Oh well...

I got the new brake pads in today so I thought I'd demonstrate the pads going into the "toaster" just for fun. The first shot you can see the top set in place and the bottom pair next to the pin and spring clip.


Pretty neat arrangement, well-engineered.

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