Gyfte

I have a question.

I have had my Canyon Grail SL CF8.0 for a year and a half now.
It currently has stock wheels (DT Swiss G1800-700c).
According to Canyon the maximum tyre clearance is 42mm.
I would like to buy a second set of wheels.

Now I have 2 options.
I buy a new 650b set and put gravel tyres on it. I don't know if that will work on my bike, and what width tyres I could fit then.
I keep my current set (G1800) and put road tyres on it.

or

I buy a new set of road wheels and put gravel tyres on the current set.

suggestions? tips?

mstateglfr 

I read canyon said 650b doesn't work for that bike. The exception being in the smallest couple of sizes where they used 650b and the same tire width max as 700c.

Your question seems to be 'should I get a wider tire or narrower tire' and only you know what you want/need in that aspect.

But if what I remember is correct, your question is moot due to design clearance and you only have 1 choice- 700c. So get some and put road tires on one wheelset and gravel tires on the other.
...or save a ton of money and just buy some fast rolling wide gravel tires which will work great on both pavement and gravel.

Gyfte

I don't know what could go wrong with putting on 650B wheels.
The intention is to put thicker tyres on them.
So the diameter will not be much different from 700c wheels.
or am i missing something

mstateglfr 

This is all just from what ive read in the past- the Grail CF was not designed to handle a wider 650b tire than what the 700c max is. And the smallest 2 sizes have 650b wheels, but the tires are not wider than the 700c tires.
Email Canyon too, if you want. Or just measure the distance and account for 5-6mm on each side.

msu2001la

With the Grail, it's not that you can't run 650b, it's that there's no advantage to running 650b. You can, but you'll still be limited to the same tire size as what would fit on 700c. (42mm)

This is usually a result of the shape of the chain stays - some bikes don't have stays that immediately flare out (or may even slightly narrow in an hourglass shape), so the clearance doesn't change between 700c and 650b.

Gyfte

ok thanks, i get it now

chas58

This. Your chainstays are relatively parallel around the BB, so if you can fit a 42mm 700c you are also limited to a 42mm 650b.

You can put a chunker tire on that front fork though. I was gonna go 40mm 700c rear, and 54mm 650b front to give myself more flotation and steering stability in sketchy conditions and keep the tire diameter the same. To test this out, I put a 54x700 on the front and liked it so much I ordered a 700c instead of a 650b for the front. Advantages: one wheel size, better rollover characteristics, and the big thing - additional stability from increasing the trail by ~10mm. 54x700 is a tight fit, so I use 50mmx700c front, 40x700c rear. Works great (and IMHO, I really see no need / advantage to going wide in the rear - that seat post is so cushy).