Tire widths on an RS

Discussion in 'Airheads' started by headtube, Nov 18, 2012.

  1. headtube

    headtube 6 mesas de invierno!

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    This being my first RS (79) I have no idea what tire to fit on the rear. I'd like something sticky but not prone to wearing quickly. I would also like to fill out the back end a bit more then just the stock size tire. Can I go to a 120 without any swing-arm rub? Any suggestions are welcome. Thanks.
    #1
  2. ozmoses

    ozmoses Ride On

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    I've found widths to vary a bit by manufacturer. People do fit a 120, the one on my /7 rubbed slightly.

    Personally, I go 110 or preferably the 4.00.
    #2
  3. ME 109

    ME 109 Long timer

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    Plus one, for 110 or 4:00

    No need for a 120.
    The narrower the tyre, the more it pisses off sports bike riders.:D
    #3
  4. bikerfish

    bikerfish flyfishandride

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    yep, a 110 will fit just fine and do the job. some 120s will fit without rubbing, some will rub, just have to try em and see. I used to run 120s on the back of my airheads, but grew tired of struggling to get the wheel back on, so once I switched back to 110, I never looked back. bike handles just fine, and chances are you will never need more tire for street duty. if you were pushing out 90 hp, then I'd go bigger, but the stock 70hp(on a good day with the wind blowing just right and the proper humidity!) will be harnessed just fine with the 110 size tire.
    don't fall for the big back tire syndrome, just fit the proper tire and enjoy the ride.
    #4
  5. Prutser

    Prutser Long timer

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    The Bridgestone BT45 will rub in the 4.00 size !
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  6. ME 109

    ME 109 Long timer

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    Something strange going on there Pruster, I've never heard of a 4:00 in any brand rubbing?
    I've run BT45 without rubbing.
    #6
  7. Tosh Togo

    Tosh Togo Long timer

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    How wide are your wheels?... that will dictate tire choices. Bigger is NOT better; as already mentioned, going wider for "looks" is a good way to detune your bike's nice steering and response.


    :thumb :thumb

    Take a look at the the fitment charts for Michelin Pilot Activs. I've been using them on a similar bike; they handle very nicely dry or wet (but do NOT work in snow), are available in skinny sizes, and are about $180.00 a set.
    #7
  8. georgesgiralt

    georgesgiralt Been here awhile

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    Hello !
    There is a BMW service bulletin specifically warning against the use of larger tires on our bikes.
    If you put rubber with different sizes than planned by the factory, you will mis-align the wheels when the bike is angled from the vertical. And this is not good.... But it is your life.
    #8
  9. Byron1

    Byron1 Been here awhile

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    Hey, I also have a 79 RS.

    I had Avon Roadriders on for a while... 120s... really liked them. Good amount of grip and feedback (for an airhead :D)... could take right over to the edge riding 2up and good mileage too (got over 10k on the rear and have now done about 21k on the front!). Incidentally the 120 did rub on the inside of the rear fender but only if I completely bottomed out the suspension. Never had an issue with it rubbing on the swing arm / drive shaft.... but it was a bit of a pain to take off the wheel.

    The rear is now a Dunlop D404 on a 110. Its ok, good grip but not as great mileage as I had out of the Avon (done about 8k miles with this one and it is now toast). Mind you I have been using it on worse roads.

    Hope this helps.

    Byron
    #9
  10. Prutser

    Prutser Long timer

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    I did mount a lot of them. Some bikes did not have the rubbing but most of them did.
    For some that really wanted to use that tire I used a bigger spacer between the wheel and the FD.
    It was solved with 1 or 2 mm extra clearance.

    But most went back to an other brand in 4.00

    I still think the bridgestone is a good tire.
    #10
  11. Tosh Togo

    Tosh Togo Long timer

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    Please explain how that works... :ear
    #11
  12. Moonshiner

    Moonshiner aka "B-dog"

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    I've got a '77 RS. I've got a 120 Metzler ME880 on the rear, and it works great, no rubbing at all. I had it done at a shop, so I won't speak to how difficult it was to put back together. I currently have about 10K miles on my Metzlers, and they could go for awhile yet.
    #12
  13. headtube

    headtube 6 mesas de invierno!

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    Thanks for your input guys. I will probably go with the 110 rear.
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  14. Wirespokes

    Wirespokes Beemerholics Anonymous

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    I'd stay with the 110 as well. Steering suffers with the larger 120 - doesn't flick over as easy. More work turning. The 120 will work, but it's also a bitch clearing the final drive and swingarm on installation - often requiring deflating the tire and possibly even squishing it a little. You hardly can see the tire from the back anyway, so why bother? Frankly, I think that wide tire thing is a bit overdone - and in my opinion looks kinda stupid. Those harleys with monster wide tires ... come on!

    The Bridgestones have done well for me, but recently they jumped about 50% in price.
    #14
  15. Jon-Lars

    Jon-Lars Jon-Lars

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    Stock tire width works best for a stock bike. Putting on a wider tire for the sake of appearance is pointless.

    However, if you modify the engine to increase the horsepower, a wider tire works better to apply power to the road.

    Wider rims can be laced on with a greater offset in order to clear the swingarm. Installation may require removing the rear drive entirely.

    It works for me. I have a 130/80 on my R90S. Using an 18" front wheel helped with the turning.
    #15
  16. fosterb

    fosterb Adventurer

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    we need more details on the 90 pls! and pics!!
    #16
  17. Jon-Lars

    Jon-Lars Jon-Lars

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    [​IMG]
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  18. headtube

    headtube 6 mesas de invierno!

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    Hmm... what sort of clearance do you have on that 130? Didn't think it was possible.
    #18
  19. Jon-Lars

    Jon-Lars Jon-Lars

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    Buchanan built the wheels on this one, using shouldered Akront WM3-18 front and WM5-18 rear rims.

    The rear rim was laced offset 12mm. This provides clearance from the big-tube swingarm.

    Because the tires are wide, there is plenty of "patch alignment".


    [​IMG]
    #19
  20. fosterb

    fosterb Adventurer

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    you got a build report somewhere? need some more info on that scoot, she looks beautiful!
    #20