Add a Disc Brake to ANY wheel.....

Discussion in 'Spare Parts, Tools & Product Developement' started by andyinchville1, Aug 7, 2011.

  1. andyinchville1

    andyinchville1 New Member

    HI All,

    I had a fella call me the other day and inquire about adding a disc brake to his non disc brake bicycle using (of all things) the Top Hat Sprocket Adapter.

    Wow, I had no idea what he was even talking about since I always stressed the need to START WITH a disc brake hub when using a Top Hat Sprocket Adapter.

    Anyways, I had never thought about INTENTIONALLY starting with a NON disc brake hub and working "backwards" since the Top Hat was specifically designed to use a disc brake hub to better mount a sprocket while still retaining the use of a disc brake NOT the other way around.....I guess I was not thinking "out of the box " enough! ;-0

    His concept was to take a Top Hat Sprocket adapter (Probably have to use the 1/4" offset version to be able to have clearance for the mounting hardware to be able to nut and bolt a rotor the Top Hat itself) , mount a disc rotor to it, and the use a factory "rag joint" to mount the Top Hat assembly to the wheel.....Instant home made disc brake hub!?!

    I though "wow that could work" BUT the reason for NOT using the factory rag joint in the first place was because of potential misalignment issues and run out. However, in thinking more about it, I have used plenty of rim brakes on less than perfectly trued wheels throughout the years without problems / issues.....

    Another concern I had was that braking could put more stress on the spokes than an engine accelerating the bike??....I mean in theory, good brakes (disc, rim, or coaster brakes for that matter) can usually lock a tire at will BUT a good Chinese engine or even Morini cannot break a tire loose on dry smooth gravel free pavement.

    I tried to convince him to use a disc brake hub for a proper disc brake conversion BUT on the other hand I was intrigued at the possibility of converting ANY wheel to disc brake use....What do you think?

    Also, another possible issue was cost....A person would have to buy a Disc brake assembly (caliper, rotor, and possibly even a new brake lever and brake cables unless the old parts from a previous caliper brake can be reused...(there is a company I found that sells new clamp on disc calipers and rotors for $38 but finding a used set up and modifying or shopping around can possibly save some $$), as well as buying the Top Hat itself....(His reply was that he lived in CA and that he knew many sources of cheap used bike parts so that was not an issue).

    Then too, a way would have be found to mount the disc brake caliper to the fork or frame of the bike itself (this potential problem may be solved with the kit I found so it may be a moot point but most motorized bikers are pretty handy and can probably cobble up a mount of some sort if need be)......

    I suppose almost anything is doable.....what do you think?


  2. buzbikebklyn1

    buzbikebklyn1 New Member

    Wow, that's what I call going the LONG was around!
    Yes, any thing is possible, but unless your going for a specific "look" why would you want to?
    My biggest problem with upgrading non disc bikes has always been adapting non disc forks and frames for the caliper mounts and then getting the spacing right for proper alignment.
    (its nice to collect different thickness wheel spacers for this reason)
    The Avid BB7 Cup-n-Cone, disc caliper adjustment system is easy to adapt to almost any home built set up and cures many alignment ills.
    I always knew I would just use disc hub wheels, the potential for run out/alignment difficulties is pretty high with that proposed set up.
    Why buy trouble?
    If one was FORCED to try that kind of set up, id go with the Manic Mechanic billet rear sprocket mount, that bolts to the hub body itself, and then the 1/4 KingsGears Top Hat adapter/disc rotor and then finally the sprocket its self.
    Do you see what im getting at here?
    You dont need all those extra parts ($), the extra rotating weight (bad for performance) and the possibility of excess rotor/sprocket run out (could cause a catastrophic brake failure)
    Dont you think it would be much better if you just start with disc hubs to begin with?
    It would be alot cheaper and easier to just go get disc hubs/wheels.
    One last thing, I've seen to many rag joint failures, they never stay true and they put undue stress on the spokes, spokes were not designed to take that kind of torsional force, the hub body was.
    I wouldn't use one if you paid me to
    Just my 2 cents worth.
    Last edited: Aug 10, 2011
  3. andyinchville1

    andyinchville1 New Member


    I looked at the post....I like the way the mount for the disc brake was done....Very innovative....Of course I would have loved to see if a Top Hat would have worked! ;-)

  4. buzbikebklyn1

    buzbikebklyn1 New Member

    Converting a non disc wheel to disc is kind of counter productive since its easier and cheaper to buy a set of disc wheels.
    Why waste time and money on something that can be bought cheaper?
    My problem is i have several good old non disc forks and frames that need disc brake mounts... the rears are easy, its the forks that are difficult to convert.
    Any one have a line on front end disc brake brackets?
  5. 5-7HEAVEN

    5-7HEAVEN Active Member

    How do you mount disc brake brackets on the rear of an aluminum frame?

    Like you said, rear disc wheels are the easy part.
  6. Goat Herder

    Goat Herder Member

    On a good steel frame you assemble the whole brake just as if the mount is already welded. I am kinda scared of Aluminum my self. A good tig welder and perhaps re oven baking the frame could get a nice temper assured, going? Unfortunately there are some department store bike frames that even their steel is a little Questionable. .

    Get the disk caliper exactly where it should be very important. Use a cable tie at the hand caliper '' hand brake'' to hold the disk caliper that was previously attentively put in the right respective placement. With that hand caliper at the handle bars stiffly engaged that disk caliper on the brake rotor is not gonna budge! Have the bike sitting very still as well lol.

    At this point construct your mounting bracket and spot weld it in place. Remove the cable tie etc get the disk caliper out of the way and do a professional weld!. Done!

    Do not weld a Disk caliper mount that pulls from a frame put it where it pushes into the frame or fork when hand brake is engaged.

    Most brake hardware comess with slight adjustment built in. Have all this in a neutral position before welding!
    Last edited: Aug 30, 2011
  7. pucksterpete

    pucksterpete Member

  8. Cavi Mike

    Cavi Mike Member

    The easy way for the front is just to get new forks. I really like ^that^ brake therapy kit for the rear, that's exactly what some rear-brakes look like on real motorbikes.
  9. wheelbender6

    wheelbender6 Well-Known Member

    You can find A2Z adaptors on EBay that allow you to bolt a disk caliper to your frame. I use one on my Diamondback.
    Last edited: Nov 27, 2011
  10. kgyrobotron

    kgyrobotron Member

    Razor scooter has disc brake adaptors that screw on to free wheels...sooo take rear remove sprocket and screw on your db adpt and front disc brake wheel. You have to use there rotors(bolt pattern is dif.
  11. kgyrobotron

    kgyrobotron Member

    To myself...scratch this idea...was given a razor elec. MX and it had screw on rotor adt...but when I got to the work bench i quickly seen the err of my thunking... i concur with all those who say...just buy or build a wheel/disc set-up...