How much difference does a wider tire make to the load you can carry on your touring bike? And will a wider tire make for a softer, more shock-free ride?
Framebuilder Marten Gerritsen, who runs his own bike building workshop M-gineering in Holland, answers this question for us.
Marten distributes bike parts, builds bike frames in fillet brazed steel and teaches bike maintenance courses to touring cyclists.
The Question: “Is there any load capacity advantage if a rear wheel is fitted with a 2″ tyre, instead of a 1.75″ tyre? Would a larger tyre absorb more of the shock loads?”
The Answer: “Load rating of a tyre is proportional to its width. Taking a look at the popular (and now discontinued) Schwalbe Marathon touring tyre, the rating would change from 125kg to 140kg for your example at max pressure. For a given combination of rider and luggage you can run the bigger tyre at a lower pressure for indeed a more comfy ride.
Note that a wider tyre is taller by about the same amount, so it might not clear the mudguards or fork crown. Also with a wide tyre it is very important not to overinflate, as the stresses bending the rim open might be higher than the rim might stand. This is especially true if the rim is very light or worn away on the braketracks.” -Marten of M-gineering
Thanks to Marten of M-gineering for answering the question. Get in touch to submit a question of your own to Ask A Mechanic.