I kinda like the look of dual ATE's, just want a more traditional look for the bodywork. A return to the '74 R90/6 I rode when I was 21. Guess I am become one of those old guy nostalgic vintage farts.
One time, I saw one on ebay goin' for like $20. It ended at like 7pm that night. At about 7:05, I checked, and it sold... for $20.
It's a simple story... After the introduction of the R-90 and the 90S there were reports of the small 10mm flywheel bolts that had been carried over from the R45/50/60/75 models shearing and creating quite a mess. The problem disappeared after the factory discontinued using the small bolts and went with larger fasteners. I've never owned an R90 with 10mm bolts and while I'd sure want to know if a prospective bike had em, they wouldn't be a total deal breaker. I'd just have to consider how I was going to use the bike. Some folks say that there were only a handful of R-90s issued with the 10mm fasteners but if thats true, how come it appears as if there are so many of em around?
Yeah, I ain't gonna worry too much about that one. On another note... dropped in on a buddy this evening who has a 13mm perch mounted master cylinder and braided line on his '78 R100/7 (single ATE). Either his brake needed bleeding or I might be eating a little crow re. a 12mm M/C and twin ATE's. Whatever it takes, baby. Whatever it takes.
There were two versions of the 10mm bolts. 1970-1973 used short ones, 1974-late 1975 used a longer one. In late 75 they changed the crank to 11mm bolts. I've seen the 11mm bolts fail also. If the 10s were so bad they would have had a lot more failures. I believe the reason that BMW went to the 11mm bolts is not because of inherent failure of the 10s, but because they were getting ready to launch the new engine (1000cc) in 76 and redesigned a lot of things, some that were not necessary. (rubber diode mounts comes to mind) They anticipated alot of things with the 1000 engine that were non issues. (Smaller diameter alternator rotors because of crank flex also comes to mind) the sky continues to fall. small minds think alike.( it's easier)
Thanks for the info, I'm just about ready to pull the flywheel on a 5/74(mfg. date) R90/6 to replace rear main, etc. I'll let y'all know what I find...
Thanks Max. I stand corrected. Don't know what I wuz thinkin. But I still stand pat on the rest of the statement.
Nice, I need to get mine back to a proper Monza Blue. Will probably end up painting myself though, I've never been happy with other peoples work. Had a chance to check out Dave Percival's collection up in Maine once. Talk about pre /7 BMW heaven!
Spent a bit of time this afternoon messing around with the R90/6. Upon closer examination it appears to be in a fairly clean, reasonably oil-tight state. It's a proper R90S seat cowl, as evidenced by the mounting holes on the trailing edge from the original R90S luggage rack. It's since been replaced by the R100S luggage rack pictured. The 90S fender's going to need a bit of bondo, too, to fill the holes drilled for the lower /6 fender brace, which isn't featured on an R90S. (note how clean and tidy the wheel is). Tank and fairing are in decent shape and include a functioning clock and voltmeter.
As mentioned previously, I'd no plans to do a frame up restoration on this bike, just a bit of a tidy up with an eye towards sound mechanicals and presentable cosmetics. The Good: Came with a box of parts including a new clutch cable, a fresh pair of authentic /6 exhaust gland nuts, a centre stand spring, three side covers... and a chain saw tool. There were a set of Konis lurking under the Krauser saddle bags. Nearly new rear tire. Brand new Yuasa battery. Clean mufflers with good metal and chrome finish. A bit of surface rust in the end caps, but I'm pretty sure that'll clean up just fine. btw, these were good aftermarket mufflers in their day. I bought a set new in the '80's and ran them on a '77 R100RS. They're sturdier than stock with heavier guage material forming the outer shell. These pieces have held up well. They sound good, too. Nicely motorcyley, without being obnoxious. Nice clean headpipes. But those engine guards have to go. A set of those things nearly killed me on the Blue Ridge Parkway years ago. I left them in a campground on the Angeles Crest Highway a week or so later. A look under the tank reveals more good news with a pair of brand new ignition coils. And new plug wires with original style caps. Battery tray looks reasonably decent, though I think a blast and respray are in the cards. Engine ledge under the transmission looks to be clean and oil-free. From this we can ass-u-me the rear main and trans input seals are good. Haven't taken the rear wheel off yet, but the lash doesn't appear excessive. Hopeful to find good splines. 34/11 final's okay, but I've got a line on a decent 33/11, which I prefer on a 900. Would also like to find a post '81 swingarm with the larger/stiffer tube and a rubber dampened driveshaft. The dampened driveshafts allow the final drive splines to last a long, long time. A Brown sidestand is a nice thing to find. They offer more confidence in a parking lot than the stock piece. The Bad: Really splitting hairs here to find anything negative about this bike, but the sub-frames a bit natty. Though the Krauser bag mounts are in terrific condition. Not to worry, the airheads parts trust has bequeathed a freshly powder coated /6 subframe. Thanks, Richard and Bino. The worst top clamp in recent memory? Though it looks reasonably tidy and unmolested. A CC Products billet triple clamp is on the way. Thanks, Robert (aka wirewrkr) at San Jose BMW. There really isn't much in the way of "Bad" with this sweet find, and there's really no "Ugly", whatsoever. Guess I landed in a big old bucket of honey with this honey. The bodywork's stripped off and ready for delivery. The engine guards are in fine shape and open to a new home. Trade for a post '81 swingarm? Meantime the bike sits waiting for my next spell of free time. When I might just tear the top end off to clean things up and see what's in there? G'night, girls. Sweet dreams... You talk to your bikes, too, right?
I gotta know why those engine guards are bad news. I have a set close to those on my /5 and I don't really like the looks of them, but I never considered them dangerous.
Nearly forgot. There was a little "Ugly". But in light of the rest of the bike it's hardly worth mentioning...
