700c Wheels to 26" Wheels

Amoto65

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Jul 2, 2017
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Hi folks, I was wondering if anyone had converted 700c wheels on a ebike to 26" wheels ? Would it have an effect on the speedo and output on a Bosch Activeline Plus Motor bearing in mind the magnet would still be in the same place as regarding the sensor? Cheers Steve.
 

sjpt

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Jun 8, 2018
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I don't think wheel size is user adjustable; a dealer might be able to do it for you. If not, the speedo would register wrong; and you'ld lose assistance at a slightly lower (real) speed. Rim brakes would be awkward, but disk brakes should be fine.
 
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andyh2

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Jan 8, 2008
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I was thinking about getting an Sduro 4, which has 27.5" x 2.4" tyres as standard, and I calculated it would take 700 wheels with up to 42mm tyres.
 
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Amoto65

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So if I used a deeper and wider tyre on a 26" wheel it would compensate the loss of diameter in wheel size.
 

scott gaza

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Oct 20, 2018
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Sure as long as they are not to wide as to foul at the sides! i have converted a bike in the past the other way tho 26"to 700c with good off road tyre's
 
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sjpt

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They'd have to be quite fat 26" tyres to take you up to typical 700c tyre diameter. You should have plenty of clearance for diameter, but might not have enough clearance for that sort of width.
 
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RobF

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Sep 22, 2012
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It's a fair jump from 700c to 26".

I would be concerned the assistance would stop at a too low real speed, unless you can derestrict the bike.

Also bear in mind the motor and pedals will be closer to the ground, and you will under gear the bike.

Fine for steady road and cycle path use, but the pedals might ground under hard cornering or on a mountain bike trail.

So if I used a deeper and wider tyre on a 26" wheel it would compensate the loss of diameter in wheel size.
A mate of mine changed a skinny tyred 700c to a podgy tyred 650b.

The circumferences were close to identical.
 

Sturmey

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Jan 26, 2018
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How about a 69er i.e 26 inch on rear and 700 with larger tyre (29) on front. Then transfer speed sensor (if possible, but might involve piecing extra wire length) to front wheel so there will be no speed error.

 
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Bikes4two

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Feb 21, 2020
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I suppose the obvious question to ask, is why are you wanting to convert from 700c to 26"?

What are you looking to gain?
 

RobF

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Sep 22, 2012
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Love the Activeline plus but not as keen on wheel size, does anyone do a Bosch motor with 26" wheels?
Riese and Muller may still do a couple of bikes with 26" wheels, but they are moving towards 650b.
 
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Martin56

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Feb 9, 2017
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I went from 700c to 650b with great success, I think 26" would bring the bottom bracket and pedals too close to the ground.