26" to 700c/650b conversion, pros and cons?

[originsoundd]

Have seen a decent amount of builds where people swap 26" wheels for larger ones and even vice versa. What's the process involved in doing this and what do you gain/lose by doing it?

 

[bikeworkshop]

If you increase the wheel size, you get a smoother roll.
If you raise the bb height by going larger overall diameter, you get a less balanced ride.
Small wheels are stronger and more flickable.

These 3 wheel sizes overlap in maximum tyre diameter, and a bicycle geometry is based around that size.

So a huge 26 is close to a sk6iny 27.5,
and a huge 27.5 is close to a skinny 700

The reality is you're better off getting a frame designed around what you want to do - tyre width is dependent on application, and frame clearance needs to match.

I'd say it's a bit like those horizontal dropouts (for hub gear or ss) with a derailleur hanger.
Why?

It's generally best to make your mind up first.
I've got 3 bikes i regularly use, they could overlap in application, but wouldn't be so good.

One frame rarely makes 2 good different bikes, and frames aren't expensive anyway, so just get the right one, and if it isn't right, change it, or have both!

If course if you like playing around with the setup of a single frame, it offers lots of opportunities, so away you go

 

[bikeworkshop]

The adoptionof disc brakes really made this possible.
Prior to that, the brake mount largely fixed the rim position.

 

[dirttorpedo]

As noted above, you basically give up tire width for an increase in wheel size and bigger wheels roll over obstacles better. I've tended towards the opposite - dropping down a wheel size to get fatter rubber and the increase in general comfort on dirt or poor roads you can achieve. I only do this on disc brake bikes where this is very simple.

 

[Tayside]

Yup, as said,if you are working with a disc frame it's only the tyre widths that can mess things up.
I built up a commuter for one of my kids from an old Orange P7 frame (26er) .
It took 700c wheels with 33mm wide tyres. With 650b it could have managed 40s.
It did help that there was some adjustment at the drop outs.

 

[Tootyred]

You also need to consider what your doing to the frames trail figure by adding bigger wheels too.

 

[Retrorockit]

Look at the 26" tire options at Rene Herse. You might not gain anything by doing that.

 

[slimjoe]

Early 90’s Fat Chance Yo Eddy with disc brakes and 650 wheels and 47mm tyres. Best handling retro bike I’ve owned. It actually feels like it was designed to be this way.

 

[wynne]

Ventana 26er with 650b wheels and 47mm tyres. Love it - and going to bigger wheel size has given me more ground clearance so fewer pedal strikes. It was clearly never designed to be like this. Also got and EBB and a mech hanger @bikeworkshop
Why does so much wrongness feel so right??!!
I say go for it. 650b is less popular than it was but I really like for what it is - rolls better than 26, livelier than 29.

 

[madjh]

26" and tires around 2.2" are equivalent to 27.5" and tire 40mm. That said, little chage, they are stil reactive, and agile. I like 27.5 more than 29" and I have recently do with my S works as I have crack problems in my Cobalt wheel set so I have no found a decent 26" wheel set but plenty in 27.5. The only problem was that the SID Team was not suitable for this diameter so I bought one Fox 32 SC with a very nice discount in RCZ.

From this:

And seven of this

To this. This frame takes 27.5 and 1.9" - 2.0" with no problem. I haven´t tried 2.1 but there is room. Not all frames can, but this do well.