Fixed Geared Bikes

ColinJ

Puzzle game developer
Really? A 14 geared rear hub! I Had no idea you could get such a multi-speed hub like that. With so many gears, I’m wondering why they don’t use them for racing. I’m curious on that one. Perhaps it’s because they don’t shift as fast on the fly.
@Littgull has Rohloffs on 2 of his bikes. I am often caught out by him sneaking a gear change in when he is riding in front of me. He either speeds up or slows down for no apparent reason, but it is because I hadn't noticed him changing gear! He can also change gear when stationary, which is very handy for standing starts on steep climbs.

There is a good review of the Rohloff HERE.

Disadvantages? Increased weight (probably not quite as much as people think though because the bike has a lot fewer parts fitted). Cost - they are very expensive, about £1,000 ($1,400-1,500?) but again - you save money on not having to buy other parts. Probably very slightly less efficient than a perfectly maintained derailleur gear system, but probably on a par with a worn/mucky one.

So, one can make adjustments to the actual fixed gear hub? This is quite interesting. If that is so, can you simply stop at the side of the road to do that? I can see this as a great way to train, and improve fitness, like you mentioned.
There is only one cog at the back and you can choose how many teeth there are the one fitted. If it has lots of teeth then you will have a low gear ratio which makes it much easier for going uphill, but a nightmare for going downhill! (You basically can't pedal fast enough and you don't have the option of freewheeling.) If you put a small cog on it would be fine for the flat and much better for going downhill but then you would really struggle on climbs. Inevitably, you would probably choose a compromise, somewhere in between the 2 extremes.

You could change the cog at the roadside but nobody in their right mind would do that except for extremely long climbs or descents. You'd have to take the wheel off and use tools on the hub to get the cog off, slide another one on then reassemble everything - a right pain!

I built myself a singlespeed bike but it has a freehub so I avoid the spinning out on descents issue by simply freewheeling downhill. It is fun to ride but I have a 52/19 gear ratio on it which is too hard for tough climbs so I generally avoid anything steeper than 8%. I can do short stretches of 10-12% but they fry my legs so I don't like to encounter too many of them. It is a great gear ratio for 16-20 mph. I can pedal to about 25 mph but my legs are then doing about 120 rpm, which is a higher cadence than I am comfortable with.
 
So, one can make adjustments to the actual fixed gear hub? This is quite interesting. If that is so, can you simply stop at the side of the road to do that? I can see this as a great way to train, and improve fitness, like you mentioned.
many fixed gear hubs have a cog each side, so you can flip the wheel giving a different ratio if you are knackered. Or one side could be a freewheel. It’s not something to casually do on the way to work though.
 

Ian H

I am an ancient randonneur, & I stop often for tea
Location
East Devon
On the fixed wheel bike you have a single cog on the back wheel, in the UK these do not usually have a freewheel on it, but logically there is no reason not to other than it breaks the ethos of a 'Fixxie' You would choose your single gear when building the bike to suit your needs, you could then change this at a later date but it's a stripdown & rebuild, not whilst riding scenerio.
If it has a freewheel, it isn't a fixed-wheel. Two different things.
 
OP
Rockn Robin

Rockn Robin

Senior Member
Location
Arizona
Heavy and inefficient. The last thing a racer wants is to waste precious watts in an inefficient drive train. Just as the last thing a heavy duty utility cyclist or a tourer in the middle of nowhere wants is the headache of repeated maintenance and component wear/failure on a fancy derailleur setup.
I’ve watched a few documentary videos of people cycling around the world, and spending time either maintaining or replacing their derailleurs. I can see where that 14 speed hub would be the right choice for touring.
 

Phaeton

Grumpy Old Barstool
Location
Oop North (ish)
I’ve watched a few documentary videos of people cycling around the world, and spending time either maintaining or replacing their derailleurs. I can see where that 14 speed hub would be the right choice for touring.
Each to their own, I personally think 'Fixies' are pointless, but some people like then, they seem themselves a strange sense of kudos, but then again I'm an old overweight middle aged no nothing who hasn't the fitness to ride one very far.
 

simongt

Über Member
Location
Norwich
On the subject of fixies, saw another one yesterday with no brakes at all. The rider must have a incomprehensible faith in his own ability to stop in an emergency.
Hmm.
 

simongt

Über Member
Location
Norwich
Indeed.It's ALMOST worth stepping out in front of him so you can sue the a**e of him for riding an illegal bike on Mrs Windsor's highway - ! :rofl:
 

normgow

Veteran
Location
Germany
many fixed gear hubs have a cog each side, so you can flip the wheel giving a different ratio if you are knackered. Or one side could be a freewheel. It’s not something to casually do on the way to work though.
Many years ago it was almost standard practice in winter to ride what we at the time called a fixed wheel. In Essex anyway it was, I don't suppose this would have been true if you lived in the Peak district or the Yorkshire Dales. A favorite hub was a DF or double fixed where as you say sprockets of different sizes could be fitted for example a 17 and a 19. These hubs normally were not fitted with a quick release axle but with practice it wasn't difficult to stop, flip the wheel and thread the chain back on using a ring spanner so your fingers didn't get dirty.
The wisdom at the time was that riding a fixed gear in winter helped the budding roadman to develop a smooth pedaling style or souplesse.
 
OP
Rockn Robin

Rockn Robin

Senior Member
Location
Arizona
Heavy and inefficient. The last thing a racer wants is to waste precious watts in an inefficient drive train. Just as the last thing a heavy duty utility cyclist or a tourer in the middle of nowhere wants is the headache of repeated maintenance and component wear/failure on a fancy derailleur setup.
That’s interesting. I would assume that you could chose the hub with gears that suits your riding style and need.
If it has a freewheel, it isn't a fixed-wheel. Two different things.
Many years ago it was almost standard practice in winter to ride what we at the time called a fixed wheel. In Essex anyway it was, I don't suppose this would have been true if you lived in the Peak district or the Yorkshire Dales. A favorite hub was a DF or double fixed where as you say sprockets of different sizes could be fitted for example a 17 and a 19. These hubs normally were not fitted with a quick release axle but with practice it wasn't difficult to stop, flip the wheel and thread the chain back on using a ring spanner so your fingers didn't get dirty.
The wisdom at the time was that riding a fixed gear in winter helped the budding roadman to develop a smooth pedaling style or souplesse.
Goodness, that's a bit of a bother. What about putting a double sprocket derailleur crank assembly? Would that not achieve similar results, therefore not having to fiddle with the back wheel?
 

Ian H

I am an ancient randonneur, & I stop often for tea
Location
East Devon
Goodness, that's a bit of a bother. What about putting a double sprocket derailleur crank assembly? Would that not achieve similar results, therefore not having to fiddle with the back wheel?
No sprung tensioner will work with fixed. Any reverse pressure on the pedals will cause a slack chain and probably unship it as well.

But you wouldn't usually change your gearing during a ride.
 
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