"Top Hat" Sprocket Adapter



Hi All,

In a previous thread I showed you the prototype hub adapter version #1....This hub adapter allows one to mount a 9 hole sprocket (with enlarged center hole (if ordering from us for adapter use we will make the required center hole change at no additional cost) to the adapter which then bolts to the 6 hole disc mount....This gives the user a precise way to mount and it backspaces the sprocket on the hub for better fit and chain line angle. The version #1 hub adapter ,however, does not allow one to use the disc brake on a disc brake equipped hub. This mount weighs in at a light 3.9 ounces (way less than the factory mounts).

NOW I have made the "Top Hat" sprocket adapter which is not only super light (a feathery 2.1 ounces) BUT also allows you to use a disc brake if you so choose! All the advantages of the standard version #1 sprocket hub adapter PLUS super light weight and the ability to retain use of the disc brake system if so equipped.

Because of the vast number of frame / wheel / and disc brake combinations
I will probably have to offer a "base" sized adapter (which is designed to fit many situations) and offer custom made spacer blocks in 1/16 , 1/8 , and possibly 1/4 inch sizes to adjust everything for that PERFECT fit (well maybe to within at least 1/16 of an inch or so) on YOUR specific bike.....

Stay tuned for pricing and availability.....they are just around the corner!

All pieces are made from the same great aerospace grade 7075 T651 aluminum we make our sprockets from....I have been researching Titanium nuts and bolts but will at first make these adapters available for use with your own nuts and bolts.

I have attached some pics showing the 2 different versions our our soon to be released adapters.....) (In the green picture on the left is the Version #! hub adapter, and on the right is our "Top Hat" adapter.


PS - Finally.... Performance Ware that is Fun to Wear! ;-)
Help me name our Model....


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Hi All,

Top Hat Sprocket Adapters are now available....See eBay for sales.


I just got my top hat adapter adapter installed and will definitely use one on any motor bike I build. It took a little work to get my stock sprocket to slide over the disc tabs on the wheel, but once it was on it worked beautifully. Spokes just arn't meant to take the kind of strain the stock clamp on mounts give them. Great product!
clearance issues between sprocket / disc rotor using top hat?

Just wondering has anyone had clearance issues between sprocket & disc rotor using the top hat adapter? With std 6" rotor my disc caliper hits the sprocket. I used the 1/4" offset with 34t sprocket, looks like I solved my issue by going to a larger (8" rotor) but it seems like I am limited as to going to a larger sprocket. I am very satisfied with products ordered & the customer service I have gotten from them. Just looking for any other solutions. Building my 1st motored.Thanks..
HI Spitball,

Depending on the disc caliper you are using (there are some "wide" ones and some "narrower" ones (if yours is "wide" you may be able to find a "narrower" caliper at a bike shop that will make it work for you...or at least make it easier to work depending ion your particular install)....you can get additional clearance between the sprocket and the disc rotor by reusing the factory metal spacers (the moon shaped pieces...If your kit uses the HD 9 hole mounts)...Install them between the Top Hat and the sprocket...That should net you about an additional 1/8"....(a less "elegant" approach would be to use washers in place of or in addition to the moons shaped pieces)...

Another method some people use is to gain clearance is to space the rotor further out
using washers....Of course going too far this way may require some filing of the caliper mounts (NOT on the frame tho if you can help it....In case you make a mistake filing it is easier to replace the caliper mount than it is to fix the "lugs" on the frame)...Sometimes a
custom fabbed caliper mount on the opposite side of the "normal" mounting side may help also.

The other method you mentioned is to simply use a larger rotor....Of course that method requires either additional mounts be welded to the frame or a custom adapter plate be made to move the caliper up the rear stays using the factory frame mounts.

Hope this helps you...

Have a Happy Holidays!

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