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Tubeless conversion
NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.
Considering converting to tubeless, but have a few questions.
I dont think my rims are tubeless rims, dose it matter? And what kinda pressures can i expect to run?
Thanks for the help.
Jono
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No, doesn't matter. You can use non-tubeless rims with rim strips. If they're pinned rims, you need the full Stan's rubber strip for them to seal properly. If they're welded you can get away with the Stans tape, and a special valve (I think).
Another option is the Bontrager teflon rim strip - sort of mimics a UST rim profile and seals up brilliantly.
With tubeless you can realistically run pressures 5-10psi lower than with tubed rubber, although how much lower will depend on the individual tyre. I wouldn't go below 25psi. With non-UST tyres converted to tubeless there is an increased risk of blowing them off the rim at lower pressures, so you do that at your own risk. For non-tubeless rubber run tubeless I'd put a lower limit of 30psi depending on how much you weigh. The upside from using kevlar-belted regular tyres is they're significantly lighter than UST tyres.
I use UST rims and Stan's sealant with UST tyres: Nobby Nic 2.25 on the front at 25psi and Racing Ralph 2.1 on the back at 27-30psi depending on the track.
By the way, many thanks to the guys in the earlier tyre thread: your comments on pressures helped a lot. I'd never have considered going as low as 25 on the front, but it works great with the NN 2.25. The front feels really planted now - big change from what they were like at 30psi.
plus you'll need a floor pump as a minimum and a lot of effort in a short burst to get them to air up, but more likely you'll have to take it to a shop and get them to use a compressor (it's much easier and get's a cleaner seat on the rim).
Forgot about that bit. Yes, I use a compressor - a $99 Super Cheap Auto job. Prior to gettng that I have successfully used a service station compressor, but it took quite a few tries. Others, using UST tyres on UST rims, claim to have done it successfully with a floor pump... I have no idea how!
using UST tires too. Have to say it involves furious pumping initially and also for the tire to be seated evenly around the rim. Especially around the valve, which sounds obvious but even a mm gap and it won't go up.
Didn't know you could get a compressor that cheap Hawkeye - will definitely invest in one.
for the air compressor?
I have used my floor pump to get my tyres to seal with Fat Alberts on DT X1800 rims. so it is doable!
With no real extra effort than pumping up a tyre normally, I had no issues with Maxxis UST (Ignitor/Larsen) on non-UST Mavic rims. I did use a Stan's kit though but will have a go at a ghetto next time. Was actually surprised at how easy it was. No problems 6 months later and no flats.
Ghetto = Stans?
Or have I got that all wrong?
... a coupla wraps of black insulation tape or fibreglass strapping tape around inside of rim to cover spoke holes, and a Schwalbe 20" BMX tube (removable valve core) stretched around and sliced up the middle to substitute for the Stans rim strip.
If you want you can also go DIY for the goop - using latex, ammonia window cleaner and Slime - if you're really committed to DIY as your life philosphy.
Yes, you need an adapter for Presta valves - about two bucks at your LBS. Warning! Get the short ones so the pin in the centre of the Schrader pump head depresses the stem in the Presta valve when you apply it, otherwise you won't get any air in.
I have had no issues with UST tyres on UST rims using a floor pump.
However, I have not yet managed to get Maxis crossmark 'exceptions' on with the floor pump - and I do keep dreaming about the weight saving!!!! I think I need to get a compressor for that. Hum extra kit - never a bad thing.
hawkeye - what power compressor, and can you get the compressor to run off the car?
I had Maxis Crossmark Exceptions but with tubes. They have really thin sidewalls (which is why they are so light) so not sure how they would go tubeless unless it was just for a bike dedicated for races or somewhere without rocks (forget places like the Dam or Red Hill). I had enough issues with tearing sidewalls as it was and there's no way that the latexy goop inside a tubeless tyre would have sealed the tears.
240V compressor with a decent sized tank. 1/2 or 1 horsepower maybe? Need to check. A 12V car battery unit won't do the job: to get enough flow to pop the beads on for any tyre I've found I need about 80psi in a decent-sized tank. From memory the tank is about 70-80cm long.
Can do less pressure with UST, but if doing ghetto you need more air throughput to compensate for the looser bead. Trying to pop tyres like Crossmark eXCeptions, 60psi (max available at the servo) was very very marginal and needed bucketloads of soapy water to help seal the bead in the groove. With the home compressor, still needed detergent but it was a lot more straightforward.
With UST on UST rims, no detergent necessary. Just need to make sure the bead has no gaps around both sides of the circumference and up it goes.