Last year the Efneo GTRO3 speed crankset came out see http://www.spindlesbikes.co.uk/gtro-3-speed-crankset/ and I started thinking about updating by old Orbit touring ‘day bike’, that had some tired old STI 105 9×3 speed shifters, into a hub geared urban ‘do anything’ bike. What if I used the GTRO Crankset with an Alfine 8 speed to get 24 speed where every gear would be usable and a thick 1/8″ chain could be used. It was also an opportunity to really test the GTRO Crankset as its still an unknown quantity in terms of reliability and durability so last April I converted to hub gears.
The first problem was the that the type of shifters available were either rapid fire or grip shift. I toyed with the idea of separable drops but looking at the forums the consensus of opinion was that they move and creek too much. Then a chance meeting with a bike trekker from Bath put me onto using Jones H-bars and I re alised that the drop handlebars had to go. The build then became very straight forward with the only issue being the availability of Alfine grip shifters since Shimano has recently changed the cabling on the latest Hubs so that the shifting is the reverse of what it was. I could only get an old shifter so top speed was ‘1’ and bottom gear was ‘8’. The old Orbit had vertical dropouts so an Alfine chain tensioner was deployed. I treated myself to a new Carradice saddle bag, new front rack, that was very heavy and new mudguards.
The first thing I noticed was the speed at which gears can be changed. It’s almost instant compared to derailleur gears and gears can be changed when stationary. I found myself changing gears more often constantly tuning the cadence for the gradient. I can see why hub gears are the best solution for commuter bikes.
The next observation was the affect of the wide Jones handlebars on oncoming traffic. The width coupled with the front rack made me appear bigger and I was being given a bit more room.
The bike comes into its own when pulling heavy loads which I do all the time. It can be a pain changing derailleur gears on an incline with 40kg on the back, but with hub gears its a doddle.
So how are the GTRO gears? so far they have behaved perfectly, The Alfine has missed a gear occasionally but that may be my changing technique. The GTROs have been flawless in their operation and have provided a comprehensive range given its the equivalent of a 28/40/50 chainset. I’m still experimenting with different sized rear sprockets having started with 24 tooth, then gone down to 17, I think 20 would be ‘plenty’.
The GTRO can certainly cope with heavy loads, however I do detect slight efficiency losses in the high gear compared to 1 to 1. I have not tried to replace a cable yet as the cable is embedded in the gear shell. That would be for a future occasion. I think the guys in Poland, where GTRO originated, are working hard to get the price down and find a distributor. I will be keeping this configuration for the foreseeable future.