Kris Holm 20 inch trials cycle 2008

I am getting constant flat tires on my Kris Holm 20 inch trials. Has anyone else had problems? Any suggestions?

could you explain a litte more? like, how many flats have you gotten, and from what, and what psi you run your tire at.

ive gotten a few flats on mine, off drops where I landed badly, but only a few. If you get them just from riding, or just from pumping up your tire, there is probably something wrong.

I never had a flat yet since last fall. next time you change your tube, look inside the rim if there’s any metal piece going out of the sidewalls of the rim. I had 3 flats in the same day because of that on my old b*ke, if so, just sand it.

and +1 for what gohabsgo333 said.

I average a flat every couple of weeks under different circumstances. The last one happened right after it was fixed without doing much of anything. I reduce the psi some from the recommended.

Probably one of two things:

  1. Pinch flats. If you feel your rim hitting the ground, ever, this could be the cause.

  2. Something sharp in there that isn’t getting removed when the flats are fixed. Could be something sharp on the inside of the tire, or possibly a sharp edge inside the rim.

can anything be done about pinch flats?


One way to make pinch flats more scarce is to keep your tire at a higher psi. Try not to land on hard edges or at awkward angles.

Getting a 15" motorcross tube will help your problem. I can’t really comment on its integrity based on first hand attestation, but there are plenty of people on these forums that swear by them.

Use 22psi. Don’t use less. You are probably getting pinch flats.


just get a motorcycle tube… 15" by 2.75, a little bigger or smaller won’t hurt, but a little smaller is probably better.

I would use even more then that. I used to have my PSI that low and now I have mine usually 35-40 PSI because I started flat spotting my rim.

location, location, location

By the time you have had 3 flats, you may notice the location. Pinch flats are always on the same part of the tire you hop and land on, and are sometimes called snake bite, because of the paired cuts caused by each rim side bottoming.

If the hole is consistently happening on a different part of the rim, check extra careful this time with a soft cloth all around the inside to see if it snags on an invisible needle tip of some nasty shard.

Lastly, are you sure that you don’t just suck at handling tire irons ? Calling the pot black, I will admit to cursing the tube and being mystified in my youth when a newly repaired tire would just pop. Truth was I needed to be more careful not to pinch the tube with the iron while wrestling the tire on. Maybe you are better than that, but it is worth mentioning as a common fault.:slight_smile:

Gained a bit of weight, huh?:stuck_out_tongue:

I really depends on the weight of the rider when it comes to psi. But since people love to have exact numbers, Corbin generously supplied.

Yah it was a really hard task for me to gain those 15-20 pounds!

I still got them when I weighed around 135, but gaining weight and progressing has caused them to occur more often (not to mention I was using 20" bicycle tubes!). biggest is right though weight is a factor. If you weigh around 135 i would reccomend you raise your tire pressure to at least 30.

I think its the size of the tire tube that you are using. I would use a 20" x 2.75" or maybe a motorcycle tire, never tried it but it sounds like a good idea. It might not be PSI though, mine is at somewhere between 10 and 13 PSI and I have no problems (only for flatland). Check the inside of your rim and the inside of your tire looking for any sharp edges or what not.

I just got a KH20 Flatland and am getting constant flats. The first flat happened a few days after I got it. I thought it was a fluke, so I just threw out the tube got a new one and put the new one on. The second time, I inspected the tube and lined it up to the rim. I noticed the plastic rim protector had a small hole in it. I removed the cover and found a very sharp piece of metal sticking through. I used a pliers to push it back under the rim and thought I had fixed it. Then I got another flat last night, lined it up again and found it was in a different place. It was still facing the bottom side of the rim, but it was a much bigger hole. In fact it was a decent sized slice, instead of a hole.

I inspected the rim at that location and found nothing. It was not a double hole. Does anybody have any idea what that could have been? Too harsh with the tire levers?

So it turns out that I was pumping the tire to the min recommended PSI stated on the tire wall (85 PSI), which apparently is way more pressure than needed for a uni and apparently was causing the flats.

It was recommended to me that I run the Flatland tire to 25-35 PSI. Does that sound right?

I just reduced to about 35 PSI, and while turning is harder, the tricks I was working on (side mount, walking the wheel, jumping, riding with the saddle out in front) are now much, much easier.