CAAD 4, 26 to 650b

[Brain]

Hi, new member here. Hoping to find out if a CAAD 4 26inch wheeled frame can fit 650b wheels and if so:
What size tyres maximum
Any tips from others who have done this?

I have just inherited this and looking to put it into service as a gravel adventure/distance bike for up to 160km a day. Reckon pushing it out to 650b (27.5) will assist if I can get a larger diameter with the right tyres.
Thanks,
Brain

 

[black lightning 1987]

I haven't tried it but I'm guessing it will work with narrow tires. This discussion might prove helpful:

https://forums.thepaceline.net/showthread.php?t=245242&highlight=MTB+650B

What is the goal? The larger diameter wheels will roll over the rough stuff easier but you will have to live with the trade-offs - narrower tires and most likely higher pressure, not to mention the expense. My take would be to stick with 26" and optimize the tires and gearing for the riding you have in mind.

 

[Brain]

Thanks and really good questions/points you make. Goal is to use this as mixed terrain go everywhere longer distance bike, not as a pure mtb. Rolling efficiency will be key, I have found a book wheel / Tyre size calculator to estimate the rolling circumference of the various wheel and Tyre combination so reckon I will start there and then see if I can borrow some wheels to test for fitment and clearance. Thanks again, will post any pictures if I go ahead with it.

 

[Brian]

I would say no. There is a list here:

https://vintagecannondale.com/info/29and650b/

I would say all of the hard tails would not take a 27.5 rim+ tire.

but, It might be cool to run fat 26". I don't know how wide of a tire that frame can take.

 

[black lightning 1987]

Best to proceed with caution. I would try to borrow a wheel with a tire mounted for a test fit before buying parts that may not fit.

 

[roKWiz]

To be honest why not use it as it is. A great hardtail mountain bike.
If you want to use it on road build (or buy) a set of 26in road wheels for it.
One of my Super V's has a set of road wheels using SACH's hubs, campag rims and Specialised Turbo S road tyres 23mm from memory.
It as good as larger diameter wheels anyway IMO.

 

[Tc68]

I’ve done it & works fine!

 

[Tc68]

I run 700c on mine!