Keeping the disc brake while adding a large driven sprocket on the rear

Discussion in 'Motorized Bicycle General Discussion' started by Nehmo, Feb 24, 2013.

  1. Nehmo

    Nehmo Member

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    I realize there are a few options and some are advertised on the sides of this forum, but what's the general prevailing wisdom?
    Let's say you want to place a large chain sprocket on the left of the rear wheel but you want to retain the disc brake so the brake and sprocket can't interfere. What's a reasonable method and which parts should be employed?

    And there are really two categories of rear driven sprockets, the freewheel ones and the fixed ones. E-bikes often use a freewheel, but ICE-bikes usually are fixed.
     
  2. WightBoy

    WightBoy New Member

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    Top Hat adapter seems to be the best for this application. Link on the left right below VeniceMotorBikes
     
  3. Nehmo

    Nehmo Member

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    Have you used one?
     
  4. Dave31

    Dave31 Moderator
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    I'm using the top hat adapter. But after doing all the cutting and grinding to make it work; I realized if I had just made or bought a solid sprocket I could have just bolted it directly to my wheel eliminating the top hat adapter and giving me the extra space I really wanted to run bigger disc.
     

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    #4 Dave31, Feb 28, 2013
    Last edited: Feb 28, 2013
  5. WightBoy

    WightBoy New Member

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    I have not, just the only thing I have seen for that application.
    Are you saying bolting the sprocket to the disc mounts?
     
  6. Dave31

    Dave31 Moderator
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    Yes, thats all the top hat adapter does for you. If you had a solid sprocket all you would have to do is drill out your center hole, your mounting holes and make a few collars to give a little space between the disc and sprocket for the chain.

    This is how I would have done it if I had known. I can get sprockets way cheaper then the top hat adapter. But since I had already purchased the top hat adapter I figured I'd better make it work.

    I'm running a 36t sprocket and 160mm rotor. the plan was for a 210mm rotor but the top hat adapter pushes my rotor too far out to where it hits the chain stay. So i had to go with a 160mm rotor instead.
     
  7. Desert Rat

    Desert Rat New Member

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    I have this rear axle brake setup
    http://www.bicycle-engines.com/Freewheel-Sprocket-and-HD-Axle-Kit-w-Brake.html
    but it occurs to me that it wouldn't be hard to adapt it to accommodate a disk brake, personally I like the band brake.
    but boy do you have to spread the frame:)
    http://motorbicycling.com/showthread.php?t=43709
     
  8. Nehmo

    Nehmo Member

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    What's your source for solid sprockets?
     
  9. Dave31

    Dave31 Moderator
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    My buddy makes them for me at his machine shop, usually just a 6 pack if he has material on hand. If not then i would cover that as well.
     
  10. Nehmo

    Nehmo Member

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    What happens if your machinist first scarfs down the beverage, then mistakenly cuts off his hand while making your sprockets? Then how would you feel? Really. If he were that impaired, he might have made a mistake in the sprocket fabrication.
     
  11. Dave31

    Dave31 Moderator
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    If he cuts his hand off thats on him. How would I feel about? I would not like it but not my problem. And if he messes up my sprocket, Id take it back and tell him to make me another one or fix it.

    Not everyone who drinks is a irresponsible baboon cutting there hands off. If he drinks during working hours, thats his choice.
     
  12. Andyinchville1

    Andyinchville1 Manufacturer/Dealer

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    HI,

    Just curious but how would a solid sprocket help?.....Were you thinking of a "sprotor" (combo sprocket / rotor) with the solid sprocket being directly bolted to the disc hub mount ?

    Andrew
     
    #12 Andyinchville1, Feb 28, 2013
    Last edited: Feb 28, 2013
  13. Dave31

    Dave31 Moderator
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    Without using the kit provide sprocket, i would not need the top hat adapter. Just mount it directly to my wheel. Thats all my top hat adapter is doing, allowing me to mount my kit sprocket.

    I can very easily drill out the center of a solid sprocket, and drill out the mounting holes for the disc wheel and make my own spacing the way i want to better line up everything.

    If can get my buddy to make me what i need in town and a lot cheaper I would rather go that route next time.

    Dont' get me wrong the top hat adapter is great but there really wasn't much left of it after i got it to fit. Plus, it did not allow me to run the size rotor I really wanted. If i tried, I was afraid I would compromise the top hat adapter. Wasn't very much material left just to get a 160mm rotor on there. I had to do a lot of shaving just to get the rotor to clear my chain stay.

    Who knows? The next one i do the top hat adapter may work perfectly? I've only tried it my hardrock.
     

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