R90S project, need advice on parts.

Discussion in 'Airheads' started by jhh, Mar 30, 2013.

  1. jhh

    jhh Guzzi Dork

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    So I've done the most financially irresponsible thing I could think of: I bought an R90S project bike. Actually, not so much a bike, but a truckload of boxes consisting of a '74 R90S, a '75 R90/6, and a complete '77 R80/7 parts bike. This is intended to be a near daily rider to replace my '85 R80 and not a show bike, so I'm not going to try and keep it 100% correct.

    Rear shocks: What brand? I know I have a lot of choices, right now I'm leaning towards the Ikons. I prefer a more sporty ride, and the streets here are horrible. The forks have Progressive springs. Are the Ikons my best bet for a decent mix of performance and durability, or should I look at Hagon/Progressive/etc?

    Frame decals: The PO destroyed the ones on the R90S frame when he tried to remove some surface corrosion, and I don't see them (the blue brake fluid warning label on the top tube, and the white US compliance/GVWR one on the lower right frame) in the Max parts fiche. Does anyone know where I can get a set of reproductions?

    Gaiters: Did the '74 R90S originally include these or not? I've seen pictures of them both with and without it.

    Electrical: The one thing I'm missing is a good alternator. I'm probably going to get a more powerful aftermarket one. Any thoughts on which brand to go with? I don't use heated gear, and I'm looking for reliability more than performance. Bonus points if it will still charge when that damned light bulb burns out.

    Oil cooler: Was this optional on the R90S? I've seen bikes both with an without it. Is it needed? I have both the cooler assembly and the block off plate, and I'm not sure whether I should add one more thing that can fail in favor of the lower temperatures. Thoughts?
    #1
  2. alister102

    alister102 Been here awhile

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    Works Performance on mine. They'll custom build them to your weight/ride style.
    #2
  3. chasbmw

    chasbmw Long timer

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    I use ikons on both my bikes.

    I don't think that you need an oil cooler, but I don't know we're you live.
    If you did fit an cooler, only fit it with a thermostat, you are more likely to do damage through running with too cool oil, than too hot.

    Gators were never standard on the S, standard on the 90/6.

    Good luck with the project.
    #3
  4. ontic

    ontic

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    Wasn't it shown by Rob Farmer and some infrared photos that the oil coolers self-regulate in a way and that the oil when not hot barely even flows through the cooler?
    I've got a cooler that is going on my G/S, no thermostat, but that will be a slightly hotted 1000cc engine that will be run in over 40C temps and often at slow speed/airflow.

    Gaitors look better to me, and make more sense, but then I'm not big on the 100% original thing.

    [​IMG]
    [​IMG]
    #4
  5. craydds

    craydds Long timer

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    Rear shocks - call Tom Cutter, http://rubberchickenracinggarage.com/ .
    Gaiters - not original on the R90S. I have 'em on my R90S for extra protection from dirt out here in the desert.
    Alternator - EnduraLast. Call John Rayski - http://www.euromotoelectrics.com/product-p/edl450-altkit.htm .
    Oil cooler - not original. Not needed. I put one on many years ago, took it off a few years later, been happy ever since.
    #5
  6. Plaka

    Plaka Brevis illi vita est

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    I use Koni Shocks--still. last forever, you can use the adjuster to compensate for wear, rebuildable. If the Ikons are still as good, get 'em.

    frame decals??? Just for show bikes. For riders, and especially performance bikes, peel them off to save weight.

    gaiter- appearance item. But they do provide protection to the fork tubes, which are greased or cosmolined under them.

    See what Euromotor electrics has in big alternators. Some integrate an ignition which is nice. Rick also has an inexpensive little kit that takes care of the burned out bulb problem..just a resistor and some wire. backs up the bulb.

    I run a cooler and no thermostat, high compression 100RS. Mostly it's for protection when traffic jamming at 15 miles an hour for extended periods. No lane splitting here.:cry Have a cover plate to put over it in the cold. if you use the thermostat you also need the depressed section in the header pipe to clear it. W/o the thermostat slightly longer lines are good but not an absolute necessity.
    #6
  7. craydds

    craydds Long timer

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    Rick Jones is with Motorrad Elektrik - http://www.motoelekt.com/charging.htm . He is very helpful.
    #7
  8. Plaka

    Plaka Brevis illi vita est

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    #8
  9. disston

    disston ShadeTreeExpert

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    A daily rider does not need stickers or decals.

    OEM was w/o gaiters. The addition of gaiters is more protection for the expensive fork tubes. I also think the Airhead forks look better with gaiters on them.

    Shocks are one of those "you get what you pay for" items. The Tom Cutter link is good source for good shocks.
    #9
  10. jackd

    jackd Long timer

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    I might be joining you in the 'most financially irresponsible' category in a very short time - got a line on a R90S project bike. I'm watching this thread with great interest.
    #10
  11. jhh

    jhh Guzzi Dork

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    Share some pictures! I''ll be making a real build thread once I get the frame back from the painters and get out of the planning / sorting things out of boxes phase.
    #11
  12. TheRoss

    TheRoss IBA# 522

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    I bought a barn find '74 R90S a couple of weeks ago. It has been a hell of a lot of fun so far. Today I am delivering the frame, tail frame, centerstand, battery box and triple tree plate to the powder coater!

    Once I get my pictures of the project uploaded I'll post a link.

    You'll have fun. And if you don't an R90S shouldn't be hard to sell.
    #12
  13. jackd

    jackd Long timer

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    I haven't pulled the trigger yet. A fellow at my place of employment approached me to offer a project bike in bits. Much is missing from what I can tell. I'm still trying to decide if I should pursue my original plan of putting a 'S' style fairing on a low mileage later model R100R or go with the project bike. What to do, what to do....
    #13
  14. chasbmw

    chasbmw Long timer

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    I'd always wanted an R90s, so I built one.

    [​IMG]
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  15. TINK

    TINK Been here awhile

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    See my build thread > http://www.advrider.com/forums/showthread.php?t=684054

    I went with Ikon shock and springs and am very pleased with the results.

    No gaiter = original R90S, with gaiters are an owner intalled option. I actually bought new gaiters and clamps for my PROJECT-S but in the end I went gaiter-less.

    Can't help on the electrical, my OEM charging system is working fine so far.

    Oil cooler is likely overkill, don't need it, save your money for this things.

    [​IMG]

    TINK

    #15
  16. jhh

    jhh Guzzi Dork

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    I've been following your build thread since some time in 2012, and it weighted heavily in my decision to start on this massive project of assembling a truck full of boxes into a running motorcycle. If mine turns out to be half as nice as yours, I'll be happy.

    Actually I'll be happy if it doesn't explode and kill me the instant I put fuel in it.
    #16
  17. Les_Garten

    Les_Garten Been here awhile

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    I'm Curious why you didn't just "S" your R80?

    Isn't it a Monoshock?
    #17