Tuesday 24 May 2016

Cinq5 Shift:R versus Gebla Rohbox. A long term review.

It shouldn't be this hard. Really. You may recall my mention of my new bike some time ago. I had the frame custom made around my existing Rohloff hub purchased new in 1999. Since I'm a nerd, I keep detailed records of my cycling activities and I could calculate how far I've ridden it in the intervening 17 years. I could but I can't be bothered at the moment. Shifting a Rohloff on a bike with drop handlebars is not an easy problem to solve if you don't like grip shifters. This page details a myriad of ways to achieve it but the majority are the most awful and non ergonomic cludge ups I could imagine. The Rohloff was originally intended for mountain bike racing but the actual market where it excels appears to be loaded touring and expedition bikes. I think I'm unusual in that I still use mine on a mountain bike, albeit a slightly different one. I'm a roadie, always have been. There I've said it in public. With my long term back injury, I simply can't do anything too technical off road. Not because I'm technically unable but because I can't afford to come off. Where I live we have lots and lots of gravel roads and forestry tracks. Not always open year round due to fire risk but there are always really good off road rides to do. The off road stuff is actually better than the road riding with far more interesting routes and much bigger climbs. This is the reason for the new bike, it's my go anywhere bike. And since I ride the road a lot, I wanted a similar position to my road bike(s) but tweaked a little to handle off road.

Cinq5 Shift:R cable box shortly before I killed it.

You may recall that I was an early adopter of the Cinq5 Shift:R shifters for the Rohloff. I installed them and mentioned at the time that the jury was out on them. I really wanted to like them but I had reservations. In summary:

Good

  • Ability to shift one or two gears at a time
  • Lightweight
  • Beautifully made.
Bad

  • Tricky to setup so that you could both up shift and down shift 2 gears at a time
  • Fragile
  • Shifting from the center of the bars meant that you needed to be seated to shift. Not always the case off road.
  • The tiny ratchets often slipped and failed to engage and change gear.
  • Doesn't like being fully submerged. On my bike the cable box hangs down low and I often ride through fords and rivers that cover the box. This made the slippage worse until I could clean out the box when I got home. Towards the end, I often finished rides being unable to shift any gears.
  • The shift levers require high force to change gear. This despite my best efforts using high quality cable and sensible routing. I always grind cable ends square. I have a slightly dodgy left wrist that makes it harder to change gear on that side.
  • I used the 31.8mm diameter levers. To mount these required a handlebar with a wide central section of this diameter. My 'bars are 46cm Salsa Cowbells and even with these I wasn't able to mount both levers at the same angle as the cable outers would foul each other where they exited the levers. Not a big deal, but things like that irk me.
  • The design uses the inner cable the wrong way round, the nipple is at the cable box, which means that you can't use an alternative lever without modification.

Eventually one of the tiny pawls inside the cable box simply broke (the up shift pawl) and stranded me in a high gear. Fortunately, I wasn't too far from home and I could get back easily. As a recent convert to Strava, I can say with a high degree of accuracy that the Cinq5 system only lasted 1406 km. That's pretty poor. Since the levers were new, I contacted the dealer and eventually received a replacement cable box after a 2 month wait. The levers were unmarked and in as new condition.

Cinq5 Shift:R cable box shortly after I killed it.

In the meantime, I investigated alternatives since the bike had become my favourite and I'd miss riding it. The Gebla Rohbox looked like a valid alternative, so I ordered one from SJS cycles to try out. I've used SJS sporadically over the years to buy various, otherwise hard to get, parts. The Rohbox turned up 4 days after ordering (!) not bad when you consider that I live in the middle of nowhere and that it's about as far as you can get from Somerset before you start going back again.

The Rohbox was on the bike later that same day.

In summary:

Good

  • Very simple mechanism made from robust parts
  • Uses the inner cables the right way round. ie the nipple at the lever. This means you can use pretty much any pair of levers to change gear.
  • The maker isn't a faceless organisation but is a bike maker from Germany called Georg. I'm an early adopter of his design and my unit shipped with springs that enabled it to shift two gears at a time. These didn't work well and Georg contacted me and sent out replacement springs and two new shift cables at his cost. These transformed the feel of the unit and the single gear change now has a nice feel to it. Georg is a really good guy and is happy to stand behind his product.
  • When used with ergo levers or similar, the handlebars are very clean.
  • Very easy to set up.
  • Although not sealed, the simple, robust construction is impervious to frequent river dunkings. I opened the box after having completed the same mileage on the Rohbox as on the Cinq5 system before it broke. There appears to be zero wear on the component parts.
  • I'm tending to change gear more often with the controls at my fingertips.
Bad

  • Can only shift one gear at a time. 
  • Relatively heavy compared to the Cinq5 cable box. If heavy means robust then I'm not complaining too loudly.
  • Larger than either the Cinq5 or the original Rohloff cable box.


Initially, I set up a hybrid system using the Cinq5 levers and the Rohbox. This set up worked pretty well but still had the issues with poor ergonomics for gear changes when standing and due to my left wrist issue. I used the bike like this for a few months until I found a set of second generation Campagnolo Record Ergolevers with aluminium levers. They were only made for a couple of years in the late 90s and are much sought after. I'm pretty much allergic to carbon fibre on my bikes, I can't really explain why either, just one of those things. I've rebuilt lots of Ergolevers over the years so I know my way around them pretty well and have a draw full of spare parts. I knew that I could use the levers pretty much as is and they would work but could be better if I modified them internally. I wanted to remove everything on the thumb, downshift side of each lever. I also wanted to lock the up shift lever firmly to the cable pull. The up shift lever has a pawl that locks into a ratchet depending on which of the gears you are in, it requires a few degrees of motion before it engages and I wanted to remove this motion to improve cable pull and the feel of the gear shift. The part I made simply replaces the front ratchet and is shaped very carefully to lock the lever to the pivot. With the thumb shifter mechanism completely removed, I simply needed to make a distance spacer and use a shorter bolt.
The modifications shaved a fair bit of weight from the units.

I'd already decided to ditch the auxiliary brake levers. I seldom used them and with the
Cinq5 gear shifters going at the same time it meant my bars would become much cleaner. 

The Cinq5 system used standard gear cable with the wires running length ways. Since the Rohloff does all its indexing in the hub this is unnecessary and I decided to try using brake cable outer as it is more flexible and may lessen the force required on the cable. I can feel a slight sponginess in the system as the cable compresses but combined with the longer shift levers on the Ergolevers, the force required to change gear is reduced. I can also change gear with my hands either on the hoods or in the drops. Finally, I can now change gear when out of the saddle...

This is the best gear change I've had yet on the bike, It's not perfect and it still has some shortcomings that at present I can live with.

  • I do miss the ability to shift multiple gears at once that the grip shifter afforded. Terrain can change quickly off road and I need to be vigilant. If I pause pedalling pressure momentarily, I can rapidly shift multiple gears by pumping the ergo lever, this works well.
  • I miss the ability to see which gear I'm in. In practical terms this means that the 7/8 8/7 change can occasionally catch me out again even after owning the hub for 17 years. It also means that I can try for a lower or higher gear and discover that I'm already in it.
  • The force required to change gear varies across the range, not all gears require the same input from the shifter. In certain gears, I can't recall which ones, this means that it is occasionally possible to shift two gears instead of the single shift that you wanted. I need to stress that this is an unusual occurrence though.
  • Errr, that's it.

I have no connection to either Cinq5 or Gebla and I paid full retail prices for both units with my own money. I have since sold the brand new, warranty replacement unit from Cinq5. It was a nice try, but simply not up to the kind of riding I like to do.


In other news, I've finally started work on my 1906 Royal Enfield that I broke the last time I rode it. The handlebars are the first part to get my attention, More later.