New Horizontal Disc Dropouts
Released: 13th February 2017
Published by: James Marr
At Bamboo Bicycle Club we continually try to improve what we can offer bike builders. With dropouts there are a range that exist on the market, but very few are compatible with bamboo and our build techniques.
So for the last 6 years we have been designing and manufacturing our own. In terms of design they are as complex as a bicycle to design, as there are so many considerations with regards size of sprocket, brake fitting, rack and mudguards fitting, diameter of bamboo tubing, hemp bonding etc.
Our initial designs were very functional and worked well but often weighed too much and lacked adaptability and space for the all important accessories which we as bike builders demand.
Over the years bike trends have also changed. One of the biggest impacts is the use of disc brakes. Dropout designs therefore become more complex as there are more and more requirements.
We have 4 standard dropouts designs and at Bamboo Bicycle Club we are trying to standardize the design further to not only simplify our stock but also give our builders the adaptability to be able to run a large variety of components should they choose to. After all what’s the point of building a custom frame if you can’t use the variety of components not forgetting those beautiful thru-axle pink hubs with a fixed sprocket and disc mount!
Our latest design focuses on a horizontal dropout with disc mounts. Our previous design incorporated disc mount on the outside of the dropout, which works very well, but when fitting racks and mudguards it can be restrictive as well as removing the re-wheel.
On our new dropout we have moved the disc mount to the non-drive side chain-stay. This is a simple enough thing to do, however the complexity is that the chain needs to be tensioned by moving the rear wheel back, therefore the brake also needs to move. In an area with limited room, it was a tricky to design work but we succeeded.
The main advantage of moving the disc brake is that there is now room to fit the rear rack and mudguards as well as keeping the disc brake tucked out of the way.
Our new slotted disc dropout will be compatible with the following rear hubs:
· Shimano Alfine 3/8/11 speed hubs
· Strumey Archer 2/3/5/8 hubs
· Sram i3/Automtrix
· Single speed Disc Hub (eg. Halo Supa)
We’ve added a Derailleur mount however we would recommend a vertical dropout. Our horizontal dropout will work but we would recommend a hex-head Axle as it holds in place.
You can of course fit a rack and mudguards. Our kit comes with all the fittings for the frame, and the dropouts come with a M5 standard threaded hole.