Problem with inner tubes on FXR standard rims

**Damien_Toman** · 1st December 2010, 20:34

Recently on the track I've had problems when the front tyre heated up. It felt like my wheel was loose, was buckled, or was going flat. Every time when I checked it on returning to the pits, it seemed fine. I pumped it up a little harder and carried on.

Well, during the 2-hour race at Mt Wellington, the tyre went flat as Detlev, my team mate, was racing. He did very well staying on the bike as in the photos I could see that it was deflating over a 4-lap period.

I took the tyre off on Sunday and the front inner tube had been creased inside the tyre and it wore through on the crease, enough to puncture the tube. See photo - click on it to enlarge.

Click image for larger version.

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So, I'm now going tubeless. Anyone had any issues with Bridgestone GP125 YDC slicks on standard FXR150 rims without tubes?

Thanks

Damien

**hmurphy** · 1st December 2010, 20:40

I had a mate doing exactly that and it was completely fine! He just made a new tubeless valve for the rim. Good luck!

**Damien_Toman** · 1st December 2010, 20:53

Great. Thanks for the feedback. Can he still run fine at low pressures like 18 psi? Lower even if very cold or using wets? I'm looking forward to not having my recurring issues when the tyres heat up

.

Hope to see you at the TRRS or in 2011 at Kaitoke - awesome track.

**DMNTD:Me** · 1st December 2010, 20:58

Nice helmet there Damien...must've been a fine gentleman that sold you that sir!

**Henk** · 1st December 2010, 21:01

Tuna has been running standard rims tubeless no problems, we ran them as well on Michelles bike. Wets tend to run at 20 instead of 18 anyway.

**RDjase** · 1st December 2010, 21:11

I have got a slick and tube on the fxr front rim on Tylers bike. Its only done 1 meeting tho.
The original FXR tube was a horrible thing, oversized and had worn thru on the folds (wasnt leaking till I took the original front tyre off) The sizes on it are the same as the new replacment one but it is a much better fit

**Henk** · 1st December 2010, 21:17

Conventional wisdom with tubes and the two hour seems to be that you fit new ones before the event.
Tubeless is the way to go, if only because you don't need to be nearly as careful changing tyres.

**Dutchee** · 1st December 2010, 21:30

Originally Posted by Henk

Tuna has been running standard rims tubeless no problems, we ran them as well on Michelles bike. Wets tend to run at 20 instead of 18 anyway.

Something tells me you might want to check with him on that.

**Damien_Toman** · 1st December 2010, 21:33

Originally Posted by DMNTD

Nice helmet there Damien...must've been a fine gentleman that sold you that sir!

HaHa! Love the joker! I like the helmet too

.

**Damien_Toman** · 1st December 2010, 21:36

Originally Posted by RDjase

I have got a slick and tube on the fxr front rim on Tylers bike. Its only done 1 meeting tho.
The original FXR tube was a horrible thing, oversized and had worn thru on the folds (wasnt leaking till I took the original front tyre off) The sizes on it are the same as the new replacment one but it is a much better fit

Hi Jase. Yes the fit is probably the main issue. Anyway, if it all works without tubes I'll be very happy and I know the front end will feel better.

**Damien_Toman** · 1st December 2010, 21:44

Henk, I've seen you flying in the wet at the slippery Mt Wellington track on well-used wet tyres! Scary and very impressive (I think you were lapping me at the time - I was on slicks). I don't understand why you would run higher tyre pressures with wets - though I know, from watching you, that it works. Is it all about profile? I know that lower pressures help with temperature.

**marsheng** · 2nd December 2010, 07:17

The best way to do use a tube is to use an under size one. That way it expands like a balloon inside the tire and therefor no creases.

**kel** · 2nd December 2010, 08:51

Damien, where did you get the valves to convert to tubeless? I run wets with tubes on standard rims, problem is I cant get the front to bead up properly. Have replaced the tube, lubed the tyre lip, beaten it with a big hammer, inflated to 90psi (to chicken to go any higher) but still cant get it to take properly. More importantly when are you going to put up some more 2hr photos!

**F5 Dave** · 2nd December 2010, 10:42

Bah, skinny rims, tubes, it all comes back.

Been there done that.

There are different quality of tubes. Buy decent brand. Get small size as Marsheng says. Replace every year & before a 2 hr.

This is a kart track thing esp as we run ~18psi & the tyres flex alarmingly (which generates the heat they need at such slow speeds). Never decided whether talcum powder was a good thing or not.

But either way tubeless got rid of any issue. Decent size rims aids fitting. Slicks on Smaller rims is a compromise & a bugger to fit.

90 PSI is super dangerous. Don't. I won't go past 60. Inner tubes less.

Leave tyre in sun. Use tyre soap or similar to fit. Fit with valve removed for a big hit of pressure quick. If it doesn't bead take it down & try again after debeading. Sometimes leaving it up will get it to stretch or pop in overnight.

With tubes you need to get the tyre seated around the valve first, quite often it hangs up on the valve rubber reinforcing.

Bike shops may have fittings for smaller rim holes. Patch Rubber here in wgtn has lots of sizes, or at least used to.

**jasonu** · 2nd December 2010, 12:50

Originally Posted by Henk

Conventional wisdom with tubes and the two hour seems to be that you fit new ones before the event.
Tubeless is the way to go, if only because you don't need to be nearly as careful changing tyres.

Good advice. Last century a tube pucncture cost me and Darrin Gossamer a 2hr overall win on a 50.