I was the editor for a BSAOC newsletter for 5 years and this article came to me by a member, sounds like a lot of work but you can't beat the price, although I do like the angle grinder idea:
As time has passed I have found more and more difficulty starting my more challenging bikes. The onset of Gout and my general feebleness meant that my Goldie and Velo had not been started in years. This awful situation could not be allowed to continue so I began to research ways of starting big British singles without inducing heart failure.
My criteria was that it must be a one person operation, portable and be as cheap as possible(like me).I wanted to be able to start my bikes without having to round up a pit crew or bother anyone to help me.
The old staple of two rollers that you backed your car onto had been banned at most race tracks after a few spectacular runaways and would not be a one person operation anyway. I found some electric rollers in Australia but they were ultra expensive and the shipping more so, that disqualified them. Several places had gas powered ones but they were all heavy and expensive.
I finally found something on the web on an English forum, where a very talented guy had made some rollers for his racing sidecar outfit using a large car starter motor direct driving one roller with the other freewheeling. Not wishing to reinvent the wheel (or rollers) I decided to adapt his design to suit classic bikes. I was a bit concerned that the much smaller tire contact area of a skinny British bike tire compared to the very wide racing sidecar tire might not have sufficient grip to start a big British single. I decided to hedge my bets and leave nubs on the axles so that I could retrofit a coupling like a chain or belt between the two rollers if found necessary. As it turned out it was not needed but the nubs might come in useful later.
I went around to my buddy Bob Kee who has a yard full of interesting "stuff", he let me have a large Chevy starter motor. We then found a 4" diameter old prop shaft as a donor for the rollers and he let me have some pillow blocks and some 1" diameter steel for the axles. I thanked him for his generosity and headed home. I had some steel angle for the frame already and decided to make the device 18" by 12" big enough for the job in hand but still very portable.
I made the rollers by cutting 12" sections from the old prop shaft, it was corroded which pleased me as the lightly pitted surface was better for drive friction than a shiny one. I faced them square on my ancient lathe and turned the ends from 1/4" thick steel. I bored the ends to suit the axles and welded them together. I cut the Bendix housing off the starter motor, removed the Bendix and filed the cut surface flat. Then I cut about 1 ½" from the shaft and filed a flat on it . The drive axle was bored to suit the starter motor shaft and two holes were tapped for two 1/4" bolts to clamp onto the filed flat on the motor shaft. Grub screws would be better.
The frame was welded together and two mounting pillars were welded on to take the motor, I made the mounting bolt holes oversize to make sure there was plenty of room for adjustment. I drilled some 1/2" holes to fit the pillow blocks. When the Bendix and its housing was cut off it meant that the motor armature had only the rear bearing for support, the drive roller pillow block would support the front end in future use.
I assembled it and made sure everything revolved freely, I had to use some shim on the starter motor attachment lugs to true it up with the roller. I then cleaned it up and painted it. The next morning was going to be the test. Two leads for the battery were attached, also a foot switch to operate the solenoid. A Velocette Venom Clubman was chosen as the test article, this bike was a particularly evil one to start as I had yet to master the Choke/advance/kick start technique. It was placed onto the rollers and a tired battery was tried, no luck it barely turned it over. I got a nice new fresh battery which turned it over, but the rear wheel kept kicking sideways and jumping off.
This had not been a problem with the sidecar outfit as the two wheels left on the ground steadied it. I mounted two shopping cart wheels onto the frame and that stopped the sideways kick but still let the wheel freely revolve.
The bike was put back on and this time bingo, after pulling in the exhaust lifter and putting it in 2nd gear it chuffed over a few times and started! It was tried at least 10 times and started every time the only minor problem was getting it off the rollers, as if you tried to drive it off it just revolved the rollers faster. The aforementioned nubs I left on the axles might be used for some kind of brake to allow it to self launch. But that's something for the future. I made a wooden ramp to ease getting it on and off and raised wooden blocks to support my stubby little legs as the bike was about 4" higher when on the rollers
The whole thing cost about $30 due to my buddies’ generosity but even if you bought the components it shouldn't cost too much. The pillow blocks are expensive to buy new but a good scrounger could find used ones for much less. Just think, a couple of days tinkering for a lifetime of easily starting big singles, better than a coronary any day! .......
