Hey Lee, just use the tube that fits your rims. Those little grommets and adapters actually can cause pinching especially if your rims have a "v" in them.

That's weird. I've used presta exclusively for about 15 years and never had a leaky stem. Are these budget tubes or something?

I guess all my rims have been drilled for presta, so maybe it's the grommet that's causing problems. I usually keep the nut on the stem cinched down pretty tight, and maybe yours are moving around when you ride and causing problems. :scratch:

I believe the last two were seamless Continental tubes.

:lol

Same here. Been using them forever and haven't had any issues with them at all.





Castor - what does your buddy do when he gets a flat on the trail? Expects others to fill up his tires for him? I stopped to help a couple cute girls air up their tires on the trail this weekend, so there is another upside to carrying your own pump that fits :boobs:

I've found that presta valves are more durable when mountain biking and I find that it's easier to fill the tube with presta valves.

Some people have told me there is "weight savings" when using the presta valves but I would think that's negligible.

Not amount of time, but amount of force necessary. With Schraeder, the valve spring is stiffer.

So far neither of us have had a flat on the trail...but thankfully the trail we typically ride is a greenway around a lake with LOTS of riders...so SOMEBODY will have one (I hope :tremble: ) otherwise....he'll be sitting there while I ride 7 miles back to the truck

Oh, so you don't have a pump either? lol

I won't leave the garage without tools, extra tubes, and a pump. I've had flat tires riding a paved bike path. They can happen anywhere, ya know.

That's retarded... buy the $1 adapter and carry it with you every time you bike...

Me too... never any issue. As I think udman said, you're rims probably aren't designed for presta valves.