In the last instalment, we heard the story of how I acquired and then adapted a pretty pink fork to fit my 1990s Specialized Rockhopper frame. I had some very clear goals when building this frame up. One - it would have to be a drop-bar bike. This was both dictated by the Holdsworth build I was acquiring components from and my preference for drop bars in general. Two - it would use a relatively cheap, simple and efficient 1x transmission. I never envisaged going especially fast on this bike and would probably be spending a lot of time off-road, so wanted to use a 34T chainring.
There are a few ways I had seen old mountain bikes converted to use drop handlebars. The easiest method was to, simply, fit the handlebars (whether as a quill fitting, or using an a-head stem and an adapter, which I had done) and use a simple friction gear shifter, fitted to the ends of the handlebars. Braking would be taken over by levers such as Tektro’s venerable RL340s. The advantage of this system is that friction shifters are super simple to use and can work with any gearing configuration. The disadvantage is that this takes away the most important part (I feel) of drop handlebar shifting - the ability to shift directly from the brake hoods using combination brake/gear shifters (or ‘brifters’ if you will).
I already had a pair of Shimano Tiagra 4600 10-speed shifters set aside for this build. Now, the rear derailleur transplanted from the Holdsworth was a 7-speed - a Shimano 200GS. So far as I could tell, this pairing was bizarre enough that no one had published anything about it. I was determined, however, to see if it might work.
My usual system for any such attempted hack is, usually, to try it out and see how it goes. My first attempt used the shifters and derailleurs mated to a 7-speed cassette. I suspected this might not work. In theory, across the seven cogs of my cassette, my shifters would force the derailleur to move ten times, so the probability of a shift coinciding with a cog was low. Sure enough, with some careful adjustment of the derailler’s limit screws, I was able to shift to the highest and lowest cog, but each shift in between was either completely missed or accompanied by much slipping and skipping chain. No good.
My second attempt used a 9-speed cassette. I suspected this might suffer very similarly to the previous example but, surprisingly, it worked! It wasn’t perfect - I felt that there was some very minor chain rub on certain cogs in the middle of the cassette, but it was fine overall. In an 11-34 configuration, I was able to shift smoothly from each cog to the other with no trouble. My hunch was that ten shifts across nine cogs reduced the margin of error sufficiently that each shift was more or less likely to land on a cog.
For my last attempt, I tried an 11-36 10-speed cassette that was originally on my Stayer, just to see if it would work. It didn't, but I don't think this is the end of my experiments - I have a Shimano 105 11-speed long cage derailleur knocking about somewhere that needs some TLC, which would work nicely with the larger range cassette I plan on fitting eventually. However, I was thoroughly pleased with this outcome and it was vindication of my philosophy going into this build - ‘try it out and make things work.’
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