Fat Tire Swap and Flat Repair.
These new fat tire bikes are something special. Many have been enjoying the fun they have to offer, and even more dream about someday owning and riding one. The bigger tires they use require a little more effort when changing them and repairing flats. It isn’t that much harder than a regular bike, but it does seem to change a task into a chore. Here’s what I found during a recent tire swap.
I have been riding a Pedego Trail Tracker since it was introduced back in February. With all the miles I’ve posted it’s cool that I have yet to experience a flat tire. Still, when Don at Pedego asked me if I’d like to try the new tires that are speced on all their fat tire bikes now, I jumped at the chance. Although this is an electric-assist fat tire bike the procedure for the change is the same. The only difference is the one extra wire connection for the rear hub motor.
The bike came with Innova 26 X 4.0 sand and snow tires. They seemed to work fine, have the coolest spider tread pattern and made a interesting singing sound as they slap the pavement during a ride. I had heard from a few that they are more susceptible to puncture flats due to a inner carcass liner that isn’t tough enough. They found out the hard way during some back woods and trail riding.
These new Vee Rubber tires (Mission) have a tighter woven inner belt that will repel attacks from trail debris and thorns. They have a more aggressive tread pattern that is sure to make for easier going in sand and snow. So far I can’t tell any difference in the basic handling, but plenty more riding will help tell the tale there. They still sing, but in a different tone and not quite as loud. And I could tell that they weigh just the slightest amount more.
The Innova tire says on the sidewall to inflate to 30 psi (too much, believe me). Also there is no directional requirement. I found that around 16 to 20 psi worked good on the street, and you can go as low as 10 psi in the soft stuff. These new Vee Rubber tires suggest 8 to 22 psi. So far I am running about 16 and it feels fine. Plus the Vee Rubber tires need to be mounted so they rotate in the correct direction for best results. Keep an eye on that during installation.
Normally when I do a tire repair or swap I use my bike stand. This Trail Tracker beckoned me in a different direction. Like days of old I held the rear brake and pulled the bike over backwards until it was upside-down on the garage floor. I placed a rag under the saddle and a couple 2 x 4s with rags under the grips. I could have lifted it on the stand I guess, but this way seemed better today. It is heavier and longer than the non-powered fat tire bikes I have ridden.
When you are taking your rims off the bike it is generally best to do one at a time. You might want to do both so you can deal with the tire change on both at the same time. That’s up to you, but I did the front first. Most fat tire bikes have disc brakes, but I have seen a few with rim brakes that might need to be loosened to get the rims on and off the bike. Make sure when you are all done that the brakes line-up correctly and are adjusted well.
Just like the brakes, on the rear you will need to deal with the chain and gears. If everything goes back together like it came apart then all this will line-up fine, but make sure to check it all closely and make the needed adjustments before the test ride when you are done. If things are way out of line, then recheck your work for where you went wrong and set it right. On the whole, it is just like any other bike except the parts are larger and heavier.
With the wheel off the bike, you can use a small tool (screwdriver?) to let the air from the tire, or you can remove the valve stem insert with the correct tool. The tire will come off with tire levers, but it takes a little more time and finesse to get things to happen. On regular tires you push the bead into the rim opposite the side you are tire levering. On these you do the same, but there is not as much movement of the tire due to the wide flat rim inner contour.
Take your time and it will happen. You will find that the tube gets very small (cross-section) when fully deflated. Make sure to partially refill it before the installation so it will not get twisted inside the tire during inflation. Also pay careful attention to the rubber rim strip. Instead of being narrow and hard to push out of place, it is quite wide and the tire’s beading surface can push it out of place easily as you work the tire into place.
Once the tire and tube are back in place you will notice the tire beading surface of the tire is nowhere near the bead area on the rim. That works well as you can make sure your rim strip and the tube are in right before you start adding air. On many bike tires I’ve worked with the bead will not line up with the rim at first inflation. You want this so the tire will turn true on the rim. On these fat tires that was not a problem. The wide flat inner contour of the rim allowed the bead to find its spot on the first try.
Still, I always deflate the tube a couple times during this process to make sure the tube isn’t twisted inside the tire. At this point check to see that the valve stem is lined up with its hole and not crooked. Once the tire is inflated to spec, rotate it to check that the bead is sitting true on the rim (and you’ve got the directional arrow on the sidewall to match up with the rotation when you ride). On most bikes you can do this in your hands, but on this bike I found it easier to remount it in the bike to do the spin check.
If you are doing this all because of a flat, then of course the hole will need to be patched, or the tube will need to be replaced. Putting in a new tube is not a bad way to go, as patch kits can be hit or miss sometimes. On most of my bikes I use thorn-resistant tubes and Slime sealant, but I don’t think this is a option on a fat tire bike. Maybe it is, but that will sure add a lot of weight to your bike if you do. I do like the flat protection of the thicker tubes.
So by now your new tires are on and they hold air. Of course you have retightened all the fasteners and checked the brakes and gears. Make sure you have the wheels centered in the frame and fork. On some fat tire bikes the chain will rub the wider tire and they purposely cant the wheel in the frame to prevent that. Check that out before you remove the tires to see if it is an issue.
Last step is to hop on and enjoy your handy work with a fun bike ride. You might consider a couple laps around the block and a recheck of your work before you hit the trail. All this can be done on the road if you have the proper tools on-hand. I prefer to do it in my workshop, but sometimes you have no choice. So always keep a spare tube, a patch kit, a pump or inflator (you need a big capacity one for fat tires) and all the tools you might need if you are in the backwoods.
I like fat, Turbo Bob.
“No hour of life is lost that is spent in the saddle”.—Winston Churchill, politician.