Converting to Gravel Tires
 

My wife has a 2021 Domane SLR 7 with the Aeolus Pro 3V TLR wheel set. She wants to try a gravel ride before purchasing a true gravel bike. What is the widest gravel tire I can put on this bike with the current set-up? I was thinking 38 but am worried about possible frame damage with much mud. I'm confident a 35 will work, but for the ride she's doing (Southern AZ) a 38 would be better. TIA.

Gen 3 and Gen 4 SLR7 Domane frames are advertised by Trek as able to fit a tire with 38mm of actual width. There internet has a ton of pics of people using 40mm tires(not sure what the true widths are).

Trek's 38mm claim means they account for a few mm of clearance on each side of the tire too.
You mention a ride- is the specific single ride predicted to be muddy? If so, yeah thats a concern but an extra 3mm of room(35 vs 38mm tire) really doesnt do much for shedding mud and preventing buildup, at least in my experience.

I have an SL6 with GR1 35mm tires on the stock Paradigm 35 wheels. They measure 38mm. There is enough clearance for wider say 41mm tires but not for muddy conditions.

Do you really want to know the widest tire your bike can fit, or do you just want guesses from people on the internet? If the former, spend $10 and buy a caliper. Remove both wheels from the bike, and flip it upside down. Measure the following distances:

• Between the inside surfaces of the fork blades, about 350mm from the axle.
• Between the inside surfaces of the chainstays, at the same displacement
• Between the inside surfaces of the seatstays, at the same displacement

Take the smallest of those three values, and subtract:

• 10 mm for an OEM-ish level of clearance
• 5 mm if you are brave
• 2 mm if you absolutely do not care about abrading or even damaging the frame, and just want the biggest meats possible for one race or show, or something

The resulting number is the biggest tires that your frameset can fit.

Then you have to figure out how wide a particular tire will actually be, when mounted on your wheels. I have 25s that are wider than 28s from the same company.

I've run 40mm GR1 tires on Aeolus Pro 3V wheels on a Domane SL7 with no problems.

Top

Have you measured how wide they end up? The 3V rims are 25mm inside width like my Paradigm 25s.

And how much clearance remains with those tires in place.

Just saw the question. I had to go swap off the Aeolus Pro 51s. I used Allen wrenches to check clearance. Unless too wide. Hope this helps. The 37V wheels are also 25mm wide inside. You’re too far away from Virginia otherwise I’d loan ya the tires or wheels.

GR1 at 30 psi is 38.4 mm wide.
front Clearance Top >11.5 mm
Sides about 7.5 mm

https://cimg3.ibsrv.net/gimg/bikefor...82351d6e2.jpeg

Rear. Working.
GR1 at 41 psi 39.2 wide
Drive Side chain stay. 8 mm
Non Drive side chain stay 6 mm
seat stays way wider. 15.25 mm W/digital callipers. Equal both sides
top 19.6 mm

The non drive side chain stay clearance of 6 mm was just enough clearance for when I broke a drive side spoke a couple years ago. I soft pedaled to the car. Did not have a spoke wrench should it had rubbed.

https://cimg1.ibsrv.net/gimg/bikefor...a07883cea.jpeg
https://cimg2.ibsrv.net/gimg/bikefor...02b6cce82.jpeg

The GR1 tires worked well for the cyclocross race but I road beginner cat 5 first in the morning. So the course was not muddy except the single track. Masters +55 at the end of the day I’m glad I did not do. :D

I want a lightweight touring, gravel and cyclocross bike like a Journeyer or Checkpoint so I have more clearance for wider tires.