Does it make sense to have deep section wheels (let‘s say 45mm+ deep) with 40mm external width and roughly 32mm internal width, if I want to ride 38-40mm road tires? For example the Lightbicycle WG or the Nextie SGV (pics)? I usually only see this kind of rim widths on Gravel setups with 50mm+ tires. But I wanna know if it makes sense to run 40mm tires on those rims. Does anyone have experience with this?
It’s a straight forward Idea:
a) It makes sense to have rims and tires flush, so no bulb effect, meaning the tires sticking out on both sides. I guess this is maunly for aerodynamic and crosswind reasons, but also aestethically imo.
b) Road and Gravel rims these days are typically 23-25mm internal and roughly 32mm external. But tires on some events are going 35mm and more. I myself are running 40mm road tires (Pirelli P Zero) for ridibg a mix of paved and easy gravel roads. I would not want to go back.
so c) It would make sense to get a rim that is ~40mm external width too.
BUT: My very basic knowledge on how tires on wheels behave lead me to the intuition that there might be problems:
First, a 40mm tire designed for 23mm internal rims will blow up crazy (roughly 0.4mm per mm added to intended inner rim width, so in this case 43mm). This means one would have to choose a narrower tire, 35 or 36mm.
But these tires aren‘t designed for such wide internal widths. And: 1) the gap between tire width and internal rim width (here: 35-32=3mm) is smaller than with previous combinations (23mm tires on 17c rims or 25mm tires on 19c rims or 28mm on 21c rims -> always at least 6mm difference). 2) The difference in tire width and inner rim width is (now 3mm, then 6mm) relative to overall width would now also be much smaller.
Will this lead to major problems? Will the ture shape be weird? Will it be dangerous bc the tire separates from the rim easier? Other problems I can‘t imagine?
Thanks for any help and reports from your own experience.