1974 BMW R90 /6 Rebuild & Modifications

Discussion in 'Airheads' started by fadingfastsd, Oct 30, 2010.

  1. wirewrkr

    wirewrkr the thread-killer

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    You're not really gonna run that negative cable in the previous picture are you??
    Please say it ain't so.

    Oh and by the by, wouldn't that nattery have better clearance if you put the proper rubber mounts in on the top mounts?
    That looks pretty sketchy from here.
  2. fadingfastsd

    fadingfastsd Been here awhile

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    None of those pictures above are finalized wiring for the battery...I thought it was obvious that nothing is hooked up and the terminals are all taped up !?

    That is the exact ground cable I'm using on the bike, although in that picture its not in its final configuration at all.

    Where do you see a problem with the cable itself? (like I said ignore routing in that picture)

    I'll take some pictures of the final setup which has over 150 miles on it so far, I'm really not worried about it's reliability.
  3. fadingfastsd

    fadingfastsd Been here awhile

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    Oh and as far as the upper rubber mounts on the battery tray...they were shot on this bike. The whole battery tray was trashed, and the upper rubber mounts were rotted and warped badly. They were not reusable whatsoever.

    Since i'm on an extreme budget with this bike at the moment, they were scrapped and I hardmounted the battery for now.
    This is all up for change when I have money to go through the bike and repair/replace as needed.

    But for now, after 150 miles or so on this setup, the battery is absolutely rock solid. There has been no wear of the battery case rubbing on the air filter housing. It's held in place too tight, just isn't moving to rub.

    I'm not too worried about it...having too much fun riding the bike to go nuts over perfecting my battery tray :D
  4. wirewrkr

    wirewrkr the thread-killer

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    the rubber mounts also act as a spacer for the tray, pulling it backwards, so that battery doesn't lay right against the air filter housing as yours is.
  5. Ben Carufel

    Ben Carufel Boxer Addict

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    Cool project, Evan. Did I see your bike parked in front of True North/Urban Solace on 30th just South of University last week?
  6. melville

    melville Long timer

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    If you are on a budget, consider using VW Rabbit radiator mounts for mounting the battery tray. They're about the same thickness, have a 6mm stud on each end, and they don't cost $13/ea like the Genuine BMW part. Even though our flat twins are smooth running, BMW still felt it necessary to rubber mount the battery for best service--I'd try to keep that up.
  7. fadingfastsd

    fadingfastsd Been here awhile

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    Hey Ben, last wednesday (not this week, last week) I was at a bike meetup at Tower Bar right on University. I was parked in the lot right behind Tower Bar.

    Is that what you mean?
  8. fadingfastsd

    fadingfastsd Been here awhile

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    And it was a $40 battery, not the end of the world if it quits due to vibration. So far so good. I'll keep an eye on it, but I'm not worried. She's staying solid mounted as is until I see damage to the battery case start occurring.
  9. fishkens

    fishkens Long timer

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    Being that you're on a budget, that doesn't seem like the most economical approach. But keep on workin' and ridin'.
  10. fadingfastsd

    fadingfastsd Been here awhile

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    I guess my point was that by the time the battery does possibly fail from it's solid mounting, I will not be broke anymore and can completely redo the battery tray and mounting system.
  11. fishkens

    fishkens Long timer

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    Fair enough. It'd be nice if we always had all money to spend as much as we wanted on bikes (and cars, boats, etc.) all the time, eh?
  12. Ben Carufel

    Ben Carufel Boxer Addict

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    Nah, there was a blue R75 out in front of Bar Pink/True North that day. I did a triple take, 'cause my roommate has a blue R75 but no license yet, so I at first thought I was gonna get to give him hell about riding with no license ;).
  13. fadingfastsd

    fadingfastsd Been here awhile

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    haha cool. Nope that wasn't me then. I'm out riding alot, I usually ride my blue R90 every day for errands and stuff.
    Can't miss it...I'm probly the only Monza blue beat up R90 with a tractor seat and luggage rack on the back.

    If you see me around, stop me! I live in Bay Park/Clairemont area, but I'm all over town from Northpark area up to Miramar on any given day.

    On a side note, thanks so much to everybody for the help and tips with the bike.
    She's running absolutely great.

    I took it on a 200 mile ride last Sunday. Just rode my ass off all day. The bike didn't skip a beat, ran like a top all day.
  14. wirewrkr

    wirewrkr the thread-killer

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    next time ya feel like it, ride out to Joshua tree, I'll custom make a negative cable to fit.
    NC
  15. fadingfastsd

    fadingfastsd Been here awhile

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    I'd love to take a ride out to Joshua tree.
    And I'll take you up on the custom cable :)
    My Napa special Autozone cables aren't a perfect fit for old BMW's apparently...
    I'm planning a ride for the first week of January if you'll be around.
  16. wirewrkr

    wirewrkr the thread-killer

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  17. bmwseeker

    bmwseeker n00b

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    Do you have this bike, if you do I would like to talk to you about some parts. email me at barryorliz@yahoo.com or call me at 770 595 8695
    Thanks
    Barry Stephens
  18. ppakyz

    ppakyz n00b

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    Nice Project!
    I'm in the middle of restoring my 76 R90/6 too. I'm stripping her all the way to the frame for a powder coat. Mine came with an original full Daytona fairing with lowers and beautiful matching Wixom side cases and trunk. Do you know what these are worth? I'm more interested in the single seat you had and the Krauser side cases. Interested in a trade of sorts if your still working on it.
    Thanks,
    ppakyz@gmail.com
  19. Ben Carufel

    Ben Carufel Boxer Addict

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    I saw his bike on Craigslist a while back, so I'm not sure he still has it.
  20. BowtieProf

    BowtieProf n00b

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    I was searching ADV today for different battery modifications and found my bike! I bought this bike a couple of years ago. I don't get to ride it as much as I would like (I have four kids), but it still goes like crazy. I bought some Hella bar end lights for when I get the right set of bars on it. I'll keep adding to the thread as I make changes.