Bicycler wrote:The problem with mountain bikes and uk commuting is the inability to fit full mudguards (fenders). Wet weather and road salt can lead to corrosion problems. The solution unfortunately involves regular cleaning of your bike and components, especially the drivetrain. If you can find one then a single speed or Alfine/nexus hub geared mountain bike might be a better idea than having an exposed derailleur drivetrain.
Most mountain bikes built before about 2000 had mudguard eyes, hence why a secondhand one is better for the task. I absolutely agree that most modern ones are so over-specialised for off-road that they are much less useful for general purpose riding.
Oh, agreed. old rigid mountain bikes were often perfect commuting machines. Ugo51 did specify a hardtail though.
Bicycler, you're right, fenders would be more than useful...I'm really tempted by mountain bikes because it's what I've always had and because I would love to get the chance to do some off-road in the weekends.
Do you reckon it would be possible to fit fenders to a MB if I fit road-tyres?
If I was to take a 27.5 wheeler the diameter would be really close to that of a road bike (700mm, am I right?) and I could fit narrower tyres and fenders. Maybe I could have spare rims with offroad tyres for the weekend, to be used without fenders, of course
Clearance for mudguards* doesn't tend to be an issue for mountain bikes (they are built with lots of clearance for mud). The issue with modern mountain bikes is that they don't tend to have the correct frame fittings for full mudguards. You can fit mountain bike clip-on guards to all mountain bikes but they are not as good for road riding. They are designed to keep the worst of the mud from flying at you on the trails (and they do tend to be muddy in the UK!) rather than keeping the bike free of water, grime and road salt.
I wouldn't be put off using a mountain bike. They may not be ideal but many, many, people in the UK use mountain bikes for commuting (sometimes long travel full suspension models still with the knobbly off-road tyres
) All it means is that you have to take care with regular washing and bike maintenance or accept that you will be paying for the replacement of bits which have gone prematurely rusty. If you give your bike an annual service, wash it regularly and oil the chain you will be doing more than 90% of British commuters. Of course the best solution is two bikes; a cheap practical one for commuting and a fun bike for the weekends.
Wheel size: It is confusing how road bikers use the old French system of tyre sizing and mountain bikers use the old British (Imperial) system. Both are used for historical reasons rather than because they give a good measurement of tyre circumference. A road (700c) rim is exactly the same diameter as a 29er mountain bike rim. Obviously you can't put a very narrow tyre on a very wide rim or a wide tyre on a very narrow rim but at similar widths the tyres are interchangeable (29 x 1.5" = 700 x 37c). Some people do as you suggest and squeeze 700c/29" tyres into 650b/27.5" frames. This is only possible if you have disc brakes rather than rim brakes. It is not an ideal compromise and the only reason to do this is that there is a much larger choice of road tyres in 700c than 650b. For this reason I strongly advise you to choose a 26" or 29" bike. There are vastly more bikes available in either of these sizes than 27.5". Every bike shop will have a choice of wheels and tyres (road and mountain bike) in both of these sizes and they tend to be significantly cheaper. 27.5"/650b is only found on specialist mountain bikes and obsolete utility bikes so your local bike shop may well not have what you need or may have a very limited selection. A commuting slick 26x1.5 tyre will happily use the same rim as your weekend knobbly 26x2.0 mountain bike tyre, or you could have a spare set of wheels if you couldn't be bothered regularly changing tyres.*'fenders' are usually referred to as 'mudguards' in British English