Monday, October 4, 2010
Drive Line Improvements.
I got the Sram 3x9 drivetrain installed, and then tried to attach it to the mid drive. No joy. The mid drive cogs are too wide for a narrow 9 speed chain. So I disassembled a wheel in the garage that had a 7 speed cluster on it. The slot was still to narrow to go on with a quick release, so I had to hack up a quick release and get some washers to make this whole thing fit in the really tiny access compartment. I bought a surley chain tensioner but now I can't adjust it, so I'll have to make a tool so that I can reach in there and tension the chain. Now if you look closely, you'll see that the chain tube is protecting the electrical wiring, but the chain actually has to go AROUND THE WIRING. This can't be efficient. I want to find a way to run the chain without tubes. Maybe that idea about hacking all the bits of automotive grade electronics from the velomobile is a good idea....
The freewheel (yes it was a freewheel) is a 7 speed. This will allow me to adjust the gear ratios once I get everything running and depending on the planned terrain. Since you can't mash on the pedals in this velo, I'm going to need a way to get really low gearing for some of the hills around San Diego.