Well I tried and failed to create a good handle for my Radial 36er from a Profile Aerobar. (See this thread for pics). It worked great except it was too wide under the seat and I found no way to arrange it to NOT chafe my thighs while pedalling.
So I tried something quite like the pure John Childs approach, with a stoker stem. The problem I have is since I’m only 5’6" tall, my seat is set low and the stokers I’d seen have too much angle (One was 37 degrees and one was 45 degrees) and the “boom” part didn’t clear the front of the seat.
Then I found a cool one with only 25 degree rise here, but there’s no picture. Here’s a picture of the stoker I used at another store which carries it.
This stoker accepts a plain 22mm quill type bike stem, so no welding. To that I attached a cut-down piece of handlebar and MTB climbing pegs.
I may need another stem w/less rise, but we’re getting close here. I rode a mile to test and it seemed just a tad high, but pretty comfy.
Well, I need the part of the handle that holds on the cover, but I guess I could remove the gripper part. I guess because so far I haven’t actually destroyed anything and could still make it the way it was.
The stoker stem was about $60 shipped, which is by far the most expensive part. The quill stem could have been cheaper if I was patient and got a used one off eBay, but I paid my (very supportive) LBS guy $25 for it. The used handlebar and pegs came out of his used parts bin and were $5 together. Oh and $1 for the pair of rubber end plugs. So about $90. Jeesh, that seems like alot.
I guess this particular stoker comes without a boom and specificly calls for the use of a quill-type stem. Not even any shims in the system.
so, if i have this straight;
the “Stoker” is the piece that holds the rear handlebar of a tandem? And somehow that oldschool threaded stem fits inside perfectly? It clamps on the frame, do you think it would be the right size for a 27.2 post?
Maybe cutting the handle part off the front bump, will allow you to put it at the perfect height?
The place I bought the stoker, Airbomb, has two sizes -
Problem Solvers Adj Stoker 100-230mm115° f/26.4-27.2mm
Problem Solvers Adj Stoker 100-230mm115° f/29.4-30.2mm
(BTW - the 115 degrees noted in the product desc. measures from the vertical, so it tilts up 25 degrees from the horizontal.)
I couldn’t put one on my seatpost because my seat is way too low, so the stoker (I got the larger size) clamps onto my Radial frame. That is the smallest diameter it will clamp to. In fact I slipped in a piece of fine sandpaper to get it to hold better. The Radial’s OD of the frame is probably 29mm or so.
If you got the smaller size, and there’s enough room under your seat to have a 25 degree rising bar under there, you’re golden.
It’s not so bad compared to the alternatives… a GB4 handle is $45 and those aren’t available anymore. A v-grip handle is $110 from Scott Wallis, but it’s hard to even get a response from him. Both of those would require a CF base if you can find them and don’t want to snap your seat in half, which is another $80-$170. Plus on yours you can adjust the angle of the handles or set it further out if you wanted.