New to Airhead

Discussion in 'Airheads' started by ninepeaks9, Nov 13, 2012.

  1. craydds

    craydds Long timer

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    My mistake. I thought that was your work. Well, thanks for the link. I bookmarked it; could use that on my '74 R90/6.
    #21
  2. ninepeaks9

    ninepeaks9 Been here awhile

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    I'm finding out that Magura's brake fluid reservoir gets in the way of the handlebar control housing, expecially the brake light cable housing that sticks out further on my R100/7. I thought about rotating it just enough but then it would be hard to use the turn signal control. Need to find some other lever/MC that would give me the clearance. More product search required but the basic idea would still work. :clap
    #22
  3. craydds

    craydds Long timer

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    #23
  4. craydds

    craydds Long timer

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    JonnyCash has a thread that may help - http://www.advrider.com/forums/showthread.php?t=742109 .
    #24
  5. ninepeaks9

    ninepeaks9 Been here awhile

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    Thanks for the alternate source, but handlebar control housing on R100/7 is so huge that it gets in the way of MC reservoir on most of the lever/MC I see offered. I may have to go the route of piss cup type reservoir with hose attachment to get it out of the way.
    #25
  6. Wirespokes

    Wirespokes Beemerholics Anonymous

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    You can find a bar-mounted master used from an 81-84 airhead. Problem there is they pull one cable that goes to a splitter.

    The 79 and 80 R65 had dual pull throttles, and so did the airheads after '85. The G/S and R100R used a different style perch and your switches won't mount to them.

    Cheapest and first step for whimpy Ate brakes (or any calipers) is to open it up and clean it out. Clean the whole system and fill with fresh brake fluid. Old fluid doesn't work anywhere near as well as fresh stuff.

    More than anything, having the proper size master to caliper, will make the most difference. Your 14mm under tank master is the ideal set up for dual discs. The stock 16 or 17mm master was waay too large for duals, but the 14mm works great!

    For the bar mount master I like 13mm. The 14mm works well too.
    #26
  7. ninepeaks9

    ninepeaks9 Been here awhile

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    Basically, I'm looking for a 13mm bar mounted master for single disk/ATE front that I have. Not sure what the piston bore size is on those but sounds like the bar mounted MC from 81-84 Airhead along with their control housing could be a painless swap with mine on R100/7?
    #27
  8. disston

    disston ShadeTreeExpert

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    The calipers are in two sizes. Either 38 or 40 millimeter. The single disk system should have a 38mm caliper and the twin disk system should have a pair of 40mm calipers. I believe this is true for all years that had Ate calipers, but I can't swear to it.

    Over the years things do get switched around so what you find may not be what BMW put on your bike originally.

    There is one method to tell which calipers you have and although I've been told it's not 100% correct I think it is close to 100% correct. The 40mm calipers have a 40 stamped on the exposed body of the caliper. The 38mm calipers are not stamped.

    If it is mechanical advantage that you are after and using the smaller MC works then it would seem that putting a 40mm caliper on in place of a 38mm one would also add some advantage. Nobody seems to ever consider this.

    There is a page that gives the ratios of the different set ups you may consider, I think this was reported here earlier in this thread. Maybe it lists what gains are achieved by using the larger caliper?
    #28
  9. ninepeaks9

    ninepeaks9 Been here awhile

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    Many ways to fry a fish...

    I think given the various limitations that my stock setup presents for a handlebar mounted MC mod, I'm thinking double disk setup might be a cleaner way. Of course that requires more expense and effort. For starters, I'll need right side fork leg with another ATE caliper & rotor. Man, the cost is mounting....
    #29
  10. disston

    disston ShadeTreeExpert

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    And so we arrive again at the old converting a single disk Ate to a dual disk Ate system conundrum. Parts are getting rare is already an old adage. They can be expensive, yes. This particular conversion though is most popular with Americans and you may be able to find the needed parts on Ebay. uk or other European site. Just check to see the seller will ship to the USA.

    There is another way to solve the problem also. All the parts are pretty standard. The calipers don't care which side they are on and the rotors feel the same way. The one part that is particular is the right side slider. You need a right side slider that holds the caliper. It seems it would be difficult to make this part from a non-caliper slider but there is another way, make a right side slider from a left side slider. The process was discussed in this thread, below;

    http://www.advrider.com/forums/showthread.php?t=738951
    #30
  11. ninepeaks9

    ninepeaks9 Been here awhile

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    I had thought about that too. However, I may have a solution going back to handlebar mounted MC setup. I think I'll explore rotating the handlebar control housing away from the rider, which will result in stock lever hanging downward. Once I have the Magura MC installed, I can just unbolt the lever off. If that works, I don't have to hack off part of the control housing the stock brake lever is attached to, which would be a shame to destroy. I think I can still use turn signal control okay. I'll try and see if it will work tonight...
    #31