Stans tubeless conversion & pressure

mikeyj28

Hi

I have got a 26" front wheel with dt Swiss xr400 rims and a 2.25 Nobby nic. The front wheel has been converted to tubeless with Stans kit. What is the ideal pressure I should have in the front? I'm on a giant anthem and weigh 12 stone 3 lbs and don't do big jumps etc.
Also, does using C02 in the tyre cause the life of the sealant to shorten?

Thanks.

Chunkers1980

No idea about co2, but must mention in the kit instructions if it does.

Pressure is trial and error. I'd start at 30 psi working down and learn what works best for you in certain conditions

BG2000

mikeyj28 wrote:

Hi

I have got a 26" front wheel with dt Swiss xr400 rims and a 2.25 Nobby nic. The front wheel has been converted to tubeless with Stans kit. What is the ideal pressure I should have in the front? I'm on a giant anthem and weigh 12 stone 3 lbs and don't do big jumps etc.
Also, does using C02 in the tyre cause the life of the sealant to shorten?

Thanks.

The sealant is just rubbery particles suspended in water - once the tyre seals, the sealant dries out and leave a solid bond - no gas or anything will change that. Only physically breaking that seal will remove it.

As long as you keep your tyres well inflated, the tyre bead will stay sealed to the rim, potentially for years - that's the only thing you need to worry about. If you're not having to pump your tyres up regularly, i.e. a similar interval to running tubes, you know the seal is OK and can be left alone.

It is advisable to top-up the sealant inside the tyre every 6 months or so, although to be honest, on one of my bikes (a nice Giant like yours) I've had the same sealant inside for almost 2 years (Stans conversion too) without any maintenance needed. You need a bit sloshing around to help fill holes from thorns etc.. or just in case the tyre bead pops out of place and needs resealing. The latter should only happen if you run the tyre pressure too low and go round a corner fast, i.e. the tyre gets pulled sideways. So to sort of answer your last questions, you need to make sure you have at least enough pressure to avoid the tyre getting rolled sideways too much. You also need enough pressure to avoid the tyre 'bottoming out' when you hit rocks etc.. Even though there's no inner tube to get a pinch-flat, you can still get a similar hole in the tyre sidewall if you bottom out hitting a square edged rock. So it's a compromise between comfort and traction (low pressure) and avoiding damage to your tyre and rim (high pressure).

As mentioned already, 30psi always seems about right, especially for your 2.2 tyres. Too low a pressure is more risky at the front as a 'floppy tyre' can compromise steering, so safer to aim for a higher pressure.

Thewaylander

Run at about 22psi up front on my 2.3" and its fine.

Just go to 40 when sealsing do all the spinning, shaking and all then leave it for a night, then drop it to the desired pressure and go.

MGDriver

It sounds like you're running a simlar set-up to me; Stans Flow EX rims with 2.25 Nobby Nics, I've gone tubeless and I'm currently running 28psi in the front and rear. I started at 32psi and found I was struggling for grip when the trail was wet, I dropped to 28 and it feels much better, I'm going to try 26 on the front for the next ride and see if that is better again. I also reduced the rebound on the Forks and this seemed to help a little with the grip in the wet (placebo effect maybe?)