I have been making myself a handlebar extension for my new Coker. I wanted something modular so I could adjust things to make it fit right and also add and change things for different riding. I got a lot of inspiration from the handlebar setup in Will’s gallery.
Pictures of my JC Coker Handle are in my Miscellaneous Stuff gallery
The handlebar is mounted to the frame using part of an adjustable stoker stem for a tandem bicycle. I got the stoker stem off eBay for around $30, but you can also get them from a place like aebike for about $48.
The boom is a 400 mm x 28.6 mm Rockwerks seatpost. I cut the seat guts off with a hacksaw.
The stem is a MTB stem with about a 25 degree rise.
I got some used MTB bar ends and mounted them on a straight piece of 22.2 mm handlebar with a 25.4 mm shim. The Coda bar ends have a weird bend in them that makes them more comfortable than regular bar ends for this riding position. I had to cut the bar ends down to get them to fit the way I wanted.
The 400 mm long boom was not quite long enough so I grafted on an extension. The extension is a piece of 25.4 mm chromoly seatpost that I had laying around. It is held in place using a big double bolt BMX clamp similar to the Primo Viking. I used an XS clamp but you can’t get those any more. The clamp is designed to fit a 28.6 mm (1 1/8") seat tube and 25.5 mm (1") seat post. Half the clamp grips the seat tube and half the clamp grips the seat post.
On the extension I have mounted my computer and a bell. The computer is mounted on a stubby extension designed so you can mount a computer on aero bars. A bike shop that knows about bikes for triathletes would know about these little computer mounts.
At the end of the extension I have a “T” shaped bar to protect the computer in the event that the unicycle hits the ground after a UPD. It is a
Minoura Space Grip. aebike has them. I haven’t crashed with it yet so I don’t know how it will hold up after a UPD. It is part plastic so it may not survive. I have some ideas for a different way to protect the computer without using the Space Grip as a crash bumper. I’ll have to play around and see what works. The JC Coker Handle is still in the Beta stage and this is one of the reasons why.
The boom required some shims to get it to fit in the stoker stem holder. The stoker stem was designed to fit something close to 30 mm and the boom is only 28.6 mm. I consumed several cans of Coca-Cola and used the empty cans as shim material. I think it is possible to get a 28.6 mm to 29.8 mm shim. I’ll give that shim a try when I can get it.
The stoker stem is designed to fit a 29.8 mm seat post. My frame is only about 28.6mm in diameter where the stoker stem is mounted so this area also required the use of some shimming material. Fortunately the tandem folks make a 28.6 mm to 29.8 mm shim for mounting a stoker stem on smaller seat posts. Now I need to get two of those fancy tandem stoker stem shims.
Overall, I like the JC Coker Handle. It’s a modular setup which allows me to move the handlebar pieces to get it to fit right. I can also add new things like maybe an aero bar instead of the bar ends. Lots of possibilities. Most of the JC Coker Handle is aluminum which keeps it fairly light.
I need to figure out a better way to protect the computer without using the Minoura Space Grip as a bumper, and I’d also like to mount a water bottle somewhere. I could mount it out front like Nathan has, or I could figure out a way to mount a single water bottle under my seat. The JC Coker Handle revision Beta 3 will be out once I get these details figured out.
