Single ring chain device… Like Oli B’s…

There was a lot of excitement at Dalby……and not just the sort of excitement reserved for big weekends in remote forest with lots of secluded parking spots on offer!!!!

Oli Beck was riding a single ring set up and he had ridden it at Houffalise the week before. Now this needed some more investigation, when I caught up with him  it was a 36t front chainring running a 11t-34t rear cassette. Also there was  a new prototype chain device from MRP which was adapted from one of their excellent downhill devices. Mmmmmmmm  I thought. If they can do that then it should be pretty easy to do the same thing. A few hours later surfing the likely web sites and I had  found what I thought was the answer. DMR do a very nice and minimalist chain cage that looked like it might do the job and you can’t get much better than a Middleburn chainring. So a couple of clicks later I was waiting for a nice new 36t Middleburn hardcoat ring and a DMR Chain Cage to arrive. Unfortunately it didn’t all arrive until Thursday which meant that we had to fit it that night so that Ben could race in the Friday Night Summer Series the next night at Daventry. Of course it wasn’t that simple…. The mounting brackets did not fit onto the Seat Tube, so some serious re-engineering was required. It wasn’t possible to come up with the final solution that night so Ben and I agreed that he would run an experimental set up on Friday (this meant that there was only one mounting point on the seatstay and it needs two, so we both knew that if it went wrong it would mean the chain throwing off the ring and maybe causing all sorts of problems. I mackled it together as best as possible and we set off for the race looking to gather data for the final engineering solution.

Wow what a night! Not only did the device work but Ben went from the back of the 150 rider field to the front and was running in a battle with Adi Scott for 4th place. The device was working …. with a bit of noise and rattling, Ben and I knew we had to add some spacers here and there to make it work properly and the second mounting point was necessary for strength and stability, but, My God! it was working fine. On the last lap there was a steep, stinging climb to the finish and this is where the lack of ratios might hurt, but, despite dead legs Ben came out of the last corner and began the uphill sprint top the line with Adi trying to pass him. as they neared the line Ben rose out of the saddle and thrust ahead to take the win in the Juniors and 4th place overall. The new device had worked and the next day I bought some bits and pieces, engineered the mounting points to allow two brackets and added washers here and there to give a better chain clearance. The pictures show the final set up and in the bargain Ben has saved over half a pound in weight, most of it from rotating mass. Mission accomplished, now we have to see if it is rideable at Margam????

Ben

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