Help - bike with 650a wheels

[BSOh]

Hi all

Being so short, I ride a junior cx bike which has 650a wheels (currently with 37mm Schwalbe delta cruisers - one of the limited selection I can get for this size wheel). This wheel-size I think is not common (same as the old English 3 speed?).

My first question is mudguards - does anyone know if there will be a problem fitting the nearest to size mudguards, for example 650b (650b as I understand it is 6mm smaller diameter - 584mm vs 590mm).

My second question is wheels - Could I put a more popular wheel-size on? Presumably brakes would be a problem? (This is probably hypothetical as the bike is not worth spending that much on).

My third question is brakes - the bike has Kore canti brakes. They squeak like mad, and there's awful judder when wet. They don't fill me with confidence. I have read loads of remedies online - that some people swap to mini v's, long drop's etc but I'm not sure whether a) its worth it and it will make a difference or b) I can do it on my bike (fyi it has junior specific 9 speed Microshift sti shifters). Others say decent pads make all the difference. Any opinions on the best solution?

Any advice you can offer will be much appreciated
TIA
BSOh

 

[mjr]

You're right about it being the old English roadster size, where it's more often called 26x1⅜". New bikes are still made with it, such as some from Bobbin.

Guards - can you hold them up and see? Should be OK but it depends what clearance they were designed for.

Wheel size: It's far enough different to the most common sizes (622 and 559) that I doubt fitting either would work. If it's got beefy forks and loads of clearance, hub braked 622s might be an option but I doubt it and you'd probably have tons of toe overlap. Apart from restricted tyre and rim choices, 590s aren't bad IMO.

If your levers are designed for cantibrakes ththen Ithink mini V have the same pull and will work. Squeak and judder might be a pad problem, probably alignment, so try adjustment first. Guides on Sheldon brown and park tool websites.

 

[BSOh]

You're right about it being the old English roadster size, where it's more often called 26x1⅜". New bikes are still made with it, such as some from Bobbin.

Guards - can you hold them up and see? Should be OK but it depends what clearance they were designed for.

Wheel size: It's far enough different to the most common sizes (622 and 559) that I doubt fitting either would work. If it's got beefy forks and loads of clearance, hub braked 622s might be an option but I doubt it and you'd probably have tons of toe overlap. Apart from restricted tyre and rim choices, 590s aren't bad IMO.

If your levers are designed for cantibrakes ththen Ithink mini V have the same pull and will work. Squeak and judder might be a pad problem, probably alignment, so try adjustment first. Guides on Sheldon brown and park tool websites.

Thats really useful, thanks mjr.

 

[andrew_s]

If you can, I'd recommend switching to 650B (iso 584 mm), also known as 27.5".
This size is now common on new bikes, having largely replace 26"/559 on cyclist-level mountain bikes, though you may have to internet order rather than LBS for road tyres rather than nobblies.

Whether this will work will depend on your brakes. Can you move the blocks down towards the axle by 3 mm?

 

[BSOh]

If you can, I'd recommend switching to 650B (iso 584 mm), also known as 27.5".
This size is now common on new bikes, having largely replace 26"/559 on cyclist-level mountain bikes, though you may have to internet order rather than LBS for road tyres rather than nobblies.

Whether this will work will depend on your brakes. Can you move the blocks down towards the axle by 3 mm?

Thanks, I think they probably will, yes. I suppose I just need to decide whether new brakes are in order first now. Thanks for your help Andrew much obliged

 

[andrew_s]

Brakes will depend on the length of the up/down adjustment slot more than the type of brake.
If you can't quite, or can only just, get the blocks low enough, it may be worth using a file to make the slots longer, provided there's enough metal. If the block overhangs the top of the rim, it will go through the side of the tyre quickly, once it's worn down enough to touch.