dhdallas

I am planning on using a used Softride Norwester road bike for gravel riding. My rims state a recommended width of 32mm but measure 19mm inside. How wide can I actually go provided the chain stays are wide enough. I did a search on this forum and I did find one post where a guy said you can pretty much fit any width tire on a road rim and that he even put 2.1 inch MTB tires on a road rim. That seems a bit excessive but I was hoping to go up to 45mm. Yes or no?

DeadGrandpa

Rene Herse says that conventional rim/tire width standards are not carved in stone.
https://www.renehersecycles.com/myth...eed-wide-rims/

I think I can go to 55mm on 19mm internal width rims. You didn't mention how wide your rims are, but I am guessing 45mm tires will be fine for you, as long as you clear the chain stays. Decrease your tire pressure to something reasonable and comfortable.

Kontact 

We used to run 2" MTB tires on road width rims.

mstateglfr 

what is your rim width?

theblackbullet

I've run Panaracer Gravelking slick in a 700x38 and Gravelking SK in 700x43 on a DT Swiss R460 rim (18mm internal) and had no issues whatsoever.

mwandaw

It's a long read, but the Bicycle Rolling Resistance website concluded various rim widths had only a very minor effect on rolling resistance. They did not compare handling or other factors.

https://www.bicyclerollingresistance...rim-width-test

dhdallas

I should have included this. 19mm

t2p

not sure if this helps (road and off road can be different)

the rims on this bike have 22 mm external width

pictured above - the rims are fitted with 1” tires - but 1.9 (48 mm) and 2.1 (53 mm) tires were used the majority of the time on this wheelset

dhdallas

Thank you!

Steve B.

This. At 35 psi, with hard cornering. They never came off

Russ Roth

Actually narrower than modern road rims. I've got a NOS set of mavic 220 rims, sadly not rainbow anodized, and they are narrow enough to fit between the hooks of my daughter's Mavic CXP pro carbon rims. I remember running 26x1.95 panaracer fire XC pros on sets of those rims. Another good one is the velocity dyad which used to be the aerohead and is 18.6mm internal and is no longer considered a MTB rim but a touring and road rim but I would fit them with 26x2.1 tires BITD and today is probably a bit narrow for a road rim. All my recent road wheelsets are 19mm internal between the Mavic CXP Pro, Velocity Aileron, and even the Pub rims I built into her track rims.

dhdallas

Thanks.

Clipped_in

Wasn't rollover of the tire problematic with regard to steering and feel while cornering?

Steve B.

Nope, the tires never felt squirmy. In the 90’s they were using narrow rims to save weight, similar widths to road rims. The tires were pretty much the same width as today, my Smoke and Dart tires were. 2.25’s. We ran 35 psi as we were using tubes. The tires were designed for this setup and worked perfectly.

t2p

Smoke and Dart - there ya go !

Noonievut

A question in relation to this topic (apology for hijacking).

Are there specific rim types where exceeding the recommended max tire size is a bad idea? I have Dura-Ace C24 wheels, 15mm internal width and recommend max tire is 28mm. I would like to go to 30, maybe even 32mm. Risky?

Dura-Ace C24

RH Clark

I've experimented a bit. You just need to try it and see how it works but take it easy at first. At a certain point wider tires on narrow rims can feel wiggly, if that is a term. The stiffer the tire the wider you can get away with. Stiffness of the bike, and rims comes into play as well as how heavy the load is and how aggressive the cyclist is. You just have to try it and see how it works.

A wiggly dangerous feeling tire for me might feel like smooth butter to my much slower and much less aggressive riding wife.

blacknbluebikes 

My constraint is the crown of the fork, not the chain stays.

scubaman

I’ve ridden 1000s of miles on pavement and gravel on René Herse 26” x 2.3” tires using ~19mm internal width rims. I’ve run them with tubes, and now mainly tubeless. All works and rides great.

Ride what you’ve got, as long as it’s plausibly safe!

Camilo

FWIW, and not to be taken as gospel....

I've run 35-37mm "gravel" tires on a few different conventional (~13 or so mm internal) 700c road rims, rims that were kind of the standard width common before the popularity of "wide" road rims. No issues at all. I also used them on Velocity A23 rims (20mm internal). No difference in the performance that I could feel, although they did plump up a couple mm in general.

50PlusCycling

According to Mavic, 19mm is sufficient for wide road tires, and gravel tires. I found that I was able to mount 700x45mm Gravel King tires on 19mm wheels. I once managed to put wide tires on 14mm wheels, though it took some doing.

Leisesturm

Exactly. Why did it take 18 posts to get to this? If it's a true 'road bike', I doubt much bigger than 28mm would fit under the fork crown or brake bridge. If it is some kind of hybrid the o.p. is calling a 'road bike', then possibly 32mm to ~40mm and the rim width would absolutely be irrelevant. I've run tires as small as 28mm and over 55mm on the same rim because the bike could handle it. The rims went along with whatever the bike said was ok. What keeps tires on the rim isn't how wide the rim is, it is using the correct minimum psi for the size of the tire.
Edit: Googled the bike. 700x32mm OEM. In no way whatsoever would I expect to fit 45mm in that frame. Source.

rm -rf

38mm tires worked great on my 20.5mm internal rims. The bike was designed for 40mm or so tires.

An example of your proposed Softride Norwester. (nice bike!)
I'm guessing that you possibly might fit 28-30mm tires. With rim brakes, there's no room for 38mm or 45mm. (perhaps "long reach" specialty brakes might work, but the frame probably won't fit the big tires anyway.)

My old road bike that was designed for 23mm tires had a tight fit under the front fork with 25mm tires. That was fine in good weather, but I rode over some damp sandy residue on the road, and the grit sticking to the tire did a buzzy "zing" sound under the fork. Scratches in the paint there too. So you want at a minimum 3mm clearance, but 5mm or more would work much better.