I have a regular single speed pedal brake bike with 28 inch wheels. I would like to switch it over to 26 inch wheels. Would this cause any problems, or can I just easily change them over?
It can sometimes be done, but usually you will run into problems.
Brake compatibility: Rim brakes do not reach the rim in its new position. Disc, drum and coaster brakes are not affected.
Pedal clearance: Pedals will now be closer to ground and will hit the ground if you are not careful when turning.
Steering will be different because the geometry changes.
Gearing will be lower because smaller wheel circumference.
If you are doing this so that you can have wider tires, they do not necessarily fit into your frame.
If you are doing this to have a smaller bike, it does not work. You still have the same size frame, just closer to ground.
As already said, and my addition, things that that won't fit or cause problems:
- brakes - if caliper type or cantilevers - won't fit. Roller brakes are wheel-dependent, disc brakes are partly wheel-dependent
- bottom bracket will find itself one inch (about 2.5 cm) closer to the ground - either you will experience pedal strike or you should replace the cranks with 25mm shorter versions (if you have 172.5 you can replace those with 170, if you have the shorter already, the 167.5 are to be found however are not popular)
- mudguards (fenders in the US) will need replacing to keep the looks of the bike consistent, however fixing smaller mudguards causes problems as the bridge are further away.
If you are not put off by those issues - good luck!