HP 101 Revisited
Since Ian Denison has had quite a bit of experience and published many articles on tire pressure, rolling resistance, etc., we take this opportunity to republish the article on High Pressure 101.
Like Alan before her, Nikki has had her share of putting wheels together and in particular, changing tires. She has provided her version of changing tires 101.
She starts out by stressing how much easier high pressure tires make life for everyday wheelchair users, but is quick to point out that you better make sure you have good rim tape or you will end up with flat tires (most HP flats occur from the inside due to the tube being compromised by one of the non-bevelled holes in the rim to accommodate spokes and push rims). Tubes are not PSI rated as tires, but when you get up over 55 PSI the vast majority of straight rubber liners to protect the tube from inside damage are not strong enough to do the job and the user is well advised to use the high pressure liners or rim tape on the market or simply put a couple wraps of electrical tape over the rubber liner to avoid issues.
1. Deflate the tube, then work one side of the tire off with three tire levers (use composite as per the black Kenda ones unless you are not concerned about marking your rims).
2. Remove the tube then pull the old tire off the rim.
3. Check the liner or rim tape and replace it if necessary as per the note above.
4. Check the sidewall of the new tire for directional placement and put half the tire on the rim opposite the push rim.
5. Put the stem of the tube in and place the tube inside the tire. (Some people like to put a little air in the tube at this point and others like to use a non-messy lubricant to ensure that the tube slides into the tire well and is less likely to be pinched in the final assembly).
6. Using your hands and starting with the tire near the valve, put the tire on the rim, massaging it all the way around making sure that the tube is not being pinched anywhere. The more massaging and positioning of the tire in the deepest part of the rim you do, the easier it will be to get the whole tire on the rim.
7. If you are not able to put the tire all the way on, we recommend the use of a tire bead jack for the final few inches of tire placement.
8. Inflate the tire to the PSI recommended on the sidewall of the tire (prior to confirming that the wheel is rated to that pressure) and inspect the tire for proper seating.
9. Completely deflate the tire and check around the rim to ensure that the tube is not seated anywhere underneath the bead of the tire and then reinflate the tire to the proper PSI and put the cap on top of the valve stem and you are good to go!
Tags: tips and tricks