Plus-size riders, those who aren’t afraid to pack a heavy load in their rack, and city commuters who give their friends rides on their bikes: Have you ever wondered if bicycle tires sport a weight limit?
All bicycle tires have a weight limit. This limit is anywhere from 110 lbs (50 lbs) to 175 lbs (75 kg) per tire, with narrow tires able to carry less and wide tires able to carry more.
However, the actual load capacity of your bike is determined not only by the tires, but also by the wheel size, number of spokes, weight distribution, and a number of other factors we will discuss in a moment.
Bike Tires’ Weight Limit
As a general rule of thumb, your tires’ weight limit is determined by the maximum tire pressure that their carcasses can support. In other words, tires you inflate to a higher PSI can generally haul more than those you inflate to a lower PSI.
If you get a lot of flats and you see your friends going for months without problems, you may think that the root cause is in your weight. But, nine times out of ten, it’s really in your bike maintenance habits.
If you’re the type of rider who frequently gets pinch flats, you’re probably underinflating your tires and/or not topping them up with air every 1-2 weeks. (Bike tires lose air from sitting, even if they’re brand new.)
Pump It Up a Notch
Another thing you need to know as a bike owner is that, depending on how much you way, you may want to consider slightly overinflating your tires.
The heavier you are, says René Herse, the higher the pressure at which you should keep your tires. The manufacturer has a useful tire pressure calculator on its website that recommends the right PSI based on the tire width and combined weight of the bike and rider.
This is also backed by Lee McCormack and Joe Lindsey of Bicycling, who say that the more you weigh, the higher your tire pressure should be. If a rider who weighs 165 lbs (75 kg) pumps their tires to 100 PSI, they add, a 200 lbs (90 kg) rider should do so to 120 PSI, and so on.
Tip: Although much of a bike’s design is intended to distribute the weight of the rider evenly, for obvious reasons, the rear tire carries most of your weight than the front one does. So keep yours it slightly more inflated.
Narrow vs. Wide Tires
The golden rule is that narrow tires are able to carry less weight because, all other things equal, they inflate to a higher pressure than wide tires do.
For example, the maximum inflation pressure of 38-mm tires manufactured by René Herse Cycles is 75 PSI. At this pressure, the tires are able to support about 330 lbs (150 kg) of weight, while 26-mm tires at 105 PSI can support up to 240 lbs (110 kg).
You will rarely find a good-quality tire for a tandem that’s narrower than 30 mm. That has to do not only with the double-weight that needs to be supported but also with the pressure that is required.
If you are a large rider as I am (on good months, I weigh 200 lbs/90 kg) and you decide to go for narrow tires, they would require very high pressure in order to not get pinch flats all of the time.
Tip: Get yourself a good pair of tires, inflate them slightly more than recommended, and don’t forget to top them up every time you ride. (Racers sometimes go as high as 150-160 PSI.)
The Rims Matter, Too
When picking the right type of tires for your weight, you shouldn’t forget about the strength of the rims as well. High-performing racing bikes, for example, are not designed for thick riders, so the type of the tires wouldn’t really matter in such a case.
The good news is that the absolute majority of bikes are capable of supporting riders that weigh up to 200 lbs (90 kg) and most will be able to support 300 lbs (135 kg).
Tip: Go for rims with more spokes. Spokes connect the hub to the rim and support the weight of the rider. A high-quality saddle can also help to spread the pressure of that weight more evenly.
Do Weight Limits Matter?
The weight limit provided by the manufacturer is not the tire’s failure point. The chances are high that nothing will happen if you load a few extra pounds on your two-wheeled friend.
However, riding the bike at peak weight capacity increases the general wear and tear of the components. It also becomes a lot easier for the bike to get damaged—not only the actual tires, but also the spokes, the rim, and even the brake pads might suffer.
Even though it’s not quite an exact science as there are way too many factors to consider, you should definitely take the weight limits into consideration when choosing the tires and the bike.
The right tires will simply make your whole bike-riding experience a lot safer and more pleasant, and that’s exactly what you’re going for, right?