Can you imagine training for nearly a year for a ironman and finishing your swim only to find your bike in the transition area with a flat?
That is exactly what happened to quite a few triathletes at an ironman event a few years ago.
I heard a story from a customer about an ironman triathlon a few years ago. While the swim was going on many tires on bikes in the transition area were exploding because of the intense sun beating down on the tires and expanding the air inside. Every few minutes there was another loud blast. Boom, Boom. If you have never heard a high pressure road tire explode it sounds just like a shotgun blast.. Can you imagine the surreal setting of the transition area of 800 bikes?
The reason that they had this problem at all is because many of the riders likely pumped their tires to the maximum rating of the tire. Then when the air expanded and BOOM.
Tire pressure is often overlooked but critical aspect of how your bike handles. Higher tire pressures generally have lower rolling resistance and greater resistance to pinch flats.
So why not pump your tires to the max on every ride?
The higher pressure makes the bike feel fast but may actually be slowing you down!
If the tire is too hard it will have a tendency to vibrate and bounce which increases rolling resistance and makes for an uncomfortable ride.
Where as if the tire is too soft you will increase rolling resistance and greatly increase your chances of pinch flats.
The number on the sidewall of the tire is the maximum pressure
The manufacturer always prints the max psi on the sidewall of the tire. This is not a recommended pressure it is the maximum.
So how to you determine the ideal pressure?
There is no single simple answer because there are so many variables. Rider weight, riding style, road surface, tires, the list goes on. The best way is to do some testing in other words trial and error.
Here are some basic guidelines for pumping up
- Inflate your tires before every ride with your floor pump
- Smaller riders 120 and less should be between 90-110 psi
- Larger riders 170+ should be between 100-130psi
- Front tire should be around 5psi less than rear
- If the road or course is exceptionally smooth increase the pressure 10psi or more
- If the road is wet drop pressures 5-10 psi
- If you will be doing hard cornering or long descents drop pressure 5-10 psi
- Never inflate your tires over the manufactures maximum recommended tire pressure.
Thank you for this! Especially interesting is the recommendation for lower pressure in the front–never heard that before.
Me neither. I wonder if it’s because the rear wheel takes more force from your pedalling.@lamarshall
More weight and more side to side force. Your rear wheel has approx. 60 % of the weight so needs a little more pressure to have the same drop or tire flex. @DaveKrentz @lamarshall
Good to know! Thanks for the info. @BicycleLab @DaveKrentz @lamarshall
I am running Scwalbe Delta Cruisers 700x35c on a Linus Roadster 8 speed. I am 170 lbs. The PSI on the tires are 35-65. What would be ideal?
If you are doing mostly smooth road I would start with close to the max on the rear and slightly lower in the front. @h2odog
I am about 280lbs, I ride a Specialized CrossTrail on everything from dirt to asphalt. The Max PSI is 85lbs, this is what I fill the tires to, should it be less for me?
@Reasons2Ride I would just pup the tires to the max. You could try lowering slightly but you may get pinch flats. Do you get a lot of flats?
I recently bought a Kona Dr. Good with Continental City Ride tires, 32×622 and it reads 80 max. Woke up one morning and the tires were dead flat. Guessing you can’t let them sit too long or the bad roads have slowly knocked the air out. I’m 125lbs and again, ride very bad city roads.
thanks in advance!
I had my tire explode in the sun however it wasn’t over inflation but plastic rim tape that melted causing the tube to blow out into the spoke holes. I have since switched to fabric tape
Weird, melting rim tape. I do like most of the cloth tapes best.
My bike tire is 65 psi max. When I get to 40 psi, my floor pump begins to take a lot more effort to pump and it feels like I will pop the tire. Is this normal?
Terry
Yes, that’s normal. Some pumps are really difficult for smaller people. I strongly suggest you try a few different brands to find one that works for you. Hope this helps
How come my tire calls for 50-70 psi but when I begin putting the air in the tire I can barely squeeze any air in it beyond 40 psi. At 40 psi the tire feels maxed out? This is for a 700c schwinn. I feel like I’m not understanding something?
Its probably your pump. Try a different pump and see if that helps
Hi, I’ve been having issues with my front tire lately. I changed the inner tube 3 times but it keeps having holes within a few hours and without using the bike at all, just like that. I checked the rim and the tyre and there are no defects. The pressure recommended is 75psi, and I’ve pumped it up to 60/65 cause it did seem VERY VERY hard to pump it. The back tyre recommended pressure is 50psi. Am I doing something wrong?
Thanks
Hard to say but it could be the valve or there is something very small in the tire