The Un-Belt Drive…

10 05 2011

Hebie Chainglider...

The belt drive is the bicycle industry’s latest darling. I can’t blame anyone for that. They look slick and they are so high tech it catches everyone’s attention. The cycling press needs fuel and anything new that can be sold is fodder for that appetite. I haven’t seen a belt drive on a bike yet in the wild. I think they’ll eventually reach the same people that will spend $1.5K on a Rohloff – which is to say a few folks, but not that many. The hold up in my opinion will be the cost and the specialized frame that’s required. Unless you sell a ton of a particular component the cost can’t be reduced beyond a certain point. This is why you can get a car tire for less than the cost of a decent bike tire. It’s why a mid-grade derailleur drivetrain will always cost so little compared to any IGH setup. And it’s why a belt drive will always command a premium over a chain drive – all other things being equal.

The main advantages advanced for the belt drive are:

  • clean
  • low maintenance
  • silent
The main disadvantages most people agree on are:
  • high cost
  • requires special frame
  • requires precise chainline alignment
  • requires precise tension and fairly high tension
There have been some folks who had problems with their belt drives in snowy winter conditions like Doug from MN who went back to his chain drive setup for the winter. I’m not clear on what the service life of a belt and the associated cogs are yet, but I am willing to give them the benefit of the doubt. Even if there are some issues initially the belt manufacturers will do their best to resolve them over the next few generations of products.

SRAM 8spd chain on my Pugsley...

My Pugsley sees the worst riding conditions of any of my bikes:

  • beach sand
  • salt water
  • corrosive playa dust at burning man
  • road salt & sand in Canadian winter
  • slush
  • desert sand/dust
So far my $16 SRAM 8spd chain has held up for years with no maintenance beyond 3 or 4 lubrications and adjusting the tension 2 or 3 times. It’s silent in operation. It doesn’t requires any expensive modifications to the frame. When I do need to replace the chain it will cost another $16 and last a bunch more years. The only real downside is the chain isn’t clean to the touch. However, neither is the bike [most of the time] I get around this problem by simply not touching the chain. Like most cyclists I find that  it’s not very hard to keep one’s clothes clean while riding with minimal effort. The other thing to think about is the belt and front cog will be exposed to all the crap your wheels and tires will be exposed to. So in many areas that means they’ll get dirty even if it’s not from chain lube and you won’t want to wear light coloured pants with an unprotected belt.

Norco Corsa ST...

Now you might ask “….wouldn’t it be great if they made something that would let you run a low cost easy to work with chain, but kept your clothes clean?…” Happily they do. In the photo at the top of this post you see a Hebie Chainglider which seals your chain away from dirt and your clothes. A fully enclosed chain is essentially maintenance free – just ride the bike. If you wanted the clean clothes part without sealing off your chain completely you can get a partial chain guard like you see in the photo above. This doesn’t keep the chain perfectly clean, but it does keep you clean and frankly a chain on an IGH will keep turning around for a very very long time before it needs any attention. The nice thing with a partial chain guard is it can be used with a rear derailleur for a very low cost drivetrain.

Chain guard and derailleur...

So is there a slam dunk reason to buy a belt drive bike? For most people I would say no. If you want low maintenance just get an IGH and you are good. If you want to stay clean add a chaincase or chain guard to your ride. A couple applications where I can see the benefit of a belt drive over a chain would be for folks that travel with their bikes that pack/unpack their rides frequently and folding bikes that don’t put the chain on the inside of the fold.

Ultimately I think the lack of market penetration from belt drives won’t be because they aren’t great. It will be because chains just work so well for the cost that they are nearly impossible to displace.