Quick test: how effectively will shorts reduce the road vibrations?

Shoud you buy an expensive shorts or just lower the air tire pressure?

I have already tested many different saddles and suspension seatposts. They can have a great influence on rear end comfort of the bike. But, at least in theory, there is one more thing that you can do to reduce the road vibrations. And this is buying good shorts with padded inserts. I think it is time to find out if good shorts can really make your ride more comfortable.

But let me start with a disclaimer: shorts are very personal thing and finding one that will fit you best is no easy task. I know this from the experience. That is why in this test I don’t want to focus on the fit and overall feeling of the shorts (especially on longer rides), but I just want to measure the comfort improvement. By comfort I mean the level of vibrations that I can measure at the level of lumbar spine (which is my standard procedure when measuring rear end comfort on the bike).

This is very simple test where I wanted to compare 3 scenarios:

1. Wearing only underwear and light sweatpants.
2. Wearing cheap shorts with padded inserts and light sweatpants. By cheap I mean 15 euro cheap.
3. Wearing very well-reviewed shorts from Assos (T.milleShorts_s7). This is not the top of the line product from Assos but still costs at least 100 euro.

As you may already noticed in each scenario, I used light sweatpants. This is because it is still winter in Poland and I have to take care of my health. But I think that the testing conditions are equal, and my sweatpants are really light so they should not interfere with the results that much.

According to Cervelo, shorts are rather important when comfort is considered so I started my tests with the 25 psi air pressure using Soma Cazadero 700x42c tires. I also used a very basic Accent saddle and a non-suspended and rather stiff (no setback) carbon seatpost from FSA.

And the results?

I think that for those who follow my site for quite some time there will be no surprise that there is very little difference between wearing shorts (no matter how expensive) and not wearing them at all, when you ride at the low air pressure of 25 psi and you are using very supple tires (like Soma Cazadero). To be exact, shorts with padded inserts (both cheap and expensive) can improve the comfort by 3-4% both on a fast gravel road and bumpy forest one. Not an increase that is worth 100 euro for sure! But how about the situation when the tires are inflated to 50 psi (which is far from the suppleness that you can enjoy when riding with 25 psi).

This time the difference between wearing and not wearing shorts was rather significant. Especially on bumpy forest route you can enjoy 10% more comfy ride. But again, there was no real difference between cheap and expensive shorts. On the fast gravel route, with high frequency vibrations cheap shorts were 4% more comfy that wearing just the underwear. But again, the expensive Assos were basically on the same level of comfort (OK, there were slightly more comfortable but to be honest, you really can’t subjectively feel that small difference). The only subjective difference for me was the feeling of being slightly higher on Assos shorts (due to theirs thicker padding) but this did not translated into any significant comfort improvement in real world.


So, what can I say?

I am surprised by those results. Especially by marginal to no difference at all between cheap and expensive shorts. Of course I only tested 2 shorts and for sure there are shorts with better comfort improving padding (compared to Assos T.milleShorts_s7 series) but I honestly thing that, unless you are very attached to riding with very high air pressure, there is no real benefits of buying expensive shorts versus a cheap one (in terms of reducing road vibrations). Just lower the air pressure and find the shorts that will fit you best.


Additional note: I bought the Assos T.milleShorts_s7 shorts to do this quick review but I will be using them as my primary shorts now so expect a long term review in spring. In that review I will talk about the sweat control and other important factors that makes shorts comfortable in everyday usage.