After reading a thousand threads here on Reddit, have you thought about trying 45c tires on the rear of your Canyon Grail? Well, don’t do it. It’s not worth the trouble.
After owning a Grail with 40s, I decided to give it another shot with my new one, trying out the Continental Terra Speed 45c tires, which have fairly low side knobs.
I installed a fairly thick protective film to shield the frame from rubbing and rode about 100 km of mixed gravel terrain to test it with two sets of wheels.
- 25km on Stock DT Swiss GRC 1400 50mm (hooked 24mm IW): 44.5mm measured width and extremely limited clearance. The tire hits the chainstay every time you sprint or hit a pothole.
- 80km on Ryet X wheelset (hooked 25 IW): 44.9mm measured width. There’s simpy no room. They touched the frame basically all time and ruined most of the film. I couldn’t even hit a single off-road puddle without mud scraping onto the film. No way to stand up on the pedals or sprint. They might only be suitable for bike path riders with <400 watt peak
Here are a few photos of my Grails.
My solution?
I went back to the rear 40c with CampaBros Stage 3 inserts, so I could lower the pressure by 0.2/0.3 bar without damaging the rim or causing the tire to bulge.
The result is a 41 mm measured tire with just 0.1 bar more pressure: Plenty of clearance for any conditions and no difference in terms of comfort. I realized there’s no point in risking your frame if these are the actual differences.
Don't wreck your dream frame, guys! Put a 47mm front tire instead and let off some steam there.
by sionett
4 Comments
Good to know, I have the 1st gen and every time I get new tires I’m tempted to push it with 45s. This will help quench that for a while.
How did the front fit?
Hello mud, goodbye paint 😄
n dry conditions, the 45s are great. I ran Schwalbe G-One RS 45s at Unbound Gravel this year, but in hindsight it was a terrible choice. As soon as you hit any mud, clearance becomes a major issue. If there are stones mixed into the mud, the frame starts grinding almost immediately.
I previously ran 40s for a year and, honestly, I noticed very little difference in comfort when moving up to 45s. The extra width wasn’t worth the loss in mud clearance and risk of damage.
I added a layer of masking tape and then Gorilla Tape over the top. The smooth masking tape layer protected the paint from the adhesive, while the Gorilla Tape took the abrasion and protected the frame underneath.
The tape surface itself was badly scored and scraped, but there was zero damage to the frame.
Cool! Always good to read some real world tests.
The problem I think, is that very often stated tyre width just isn’t reliable.
The width of the wheel rim will affect the width and depth of many tires. And some tires seem to simply be wider/thinner than advertised.
I just set my grail up tubeless and measured the actual tire clearance while I had the wheels of.
I got 61mm at the front fork and 52mm at the rear down by the chain at the narrowest point.
Most people seem to say ”2-3mm on each side is enough, unless it’s muddy and rocky”
So I’ve been going crazy thinking about 42s, 45s, maybe even a 50 in the front and 45 in the back?
I don’t know lol I’m just rambling here.
I bought the grail, happy with 42s, then I saw al these comments about squeezing in 50’s and it got my hopes it.
I’m gonna try and find a nice set of thicker 40’s, or 42s, because then the stock mud guards will fit.
Or maybe go 50/42 and skip the mudguards haha.
We’ll see when the stock tires are worn out 😂