Tires blowing off Stan's Alpha 340 rims

[Tizzen]

Here are my two experiences with the tyres blowing off the stans 340:
First time happenned coming down Mt Buffalo, where speeds of around 75 km/h are not exceptional.
On a straight flat section ( speed around 40 km/h) the front blew off, resulting in a spill, slide and roll. Lost some skin, could have been worse.
This was on their first version of the rim, 28 hole, veloplugs with a single layer of thin tape, conti attack with conti light tubes at about 120 psi. The tyre was not new, maybe 500 km on it.
Second time I had just installed a brand new ultremo tubeless on a new version stans 340. Two layers of stans tape and sealant ( everything strictly according to stans instructions ) but pumped to 120 psi, without having ridden it, the tyre blew with a loud bang but stayed on the rim and lost about half the pressure. The bead was easily popped back on the rim but must have stretched because it happened again with the same tyre @ 110psi whilst riding. Again about have the air was lost, a slight wobble, pushed the tyre back on the rim and limped home.
This tyre was changed for a new ultremo tubeless and sealant and the pressure dropped to 100 psi and I have since done more than 500 km on this pair without any issues . I actually like the feel of the tubeless tyres and would like to keep riding them. I think the pressures over 100 psi were to blame together with somehow stretched beads.
I guess I will keep riding them , tubeless under 100 psi.

[PSM]

Do you guy's know how to install a tyre properly?

[tinozee]

I suppose Stan's is pushing it saying any old clincher tires will work well with their rims. Maybe the thread should be a bout that, and not a blanket statement that "tires blow off stan's 340 rims"

And I still don't get why anyone would buy a tubeless rim to run clinchers and tubes. I've got 3 pair stan's road wheels and 2 mtb pair and have put lots of miles (10K+) on them with zero blow offs. I also ride Reynolds 46 clinchers and zipp tubulars and have used pretty much every tire under the sun in all 3 types of rim racing for over 20 years. I have raced over 20 crits on stans wheels, and on nasty roads in Europe, and they simply don't blow off with tubeless tires and they NEVER flat in my experience. If you want to try these wheels, just get hutch tubeless tires and I will put money on it that they will not blow off. The ride is amazing too.

[PSM]

And I still don't get why anyone would buy a tubeless rim to run clinchers and tubes.

Because these are light weight rims.

[WMW]

And I still don't get why anyone would buy a tubeless rim to run clinchers and tubes.

You may not have noticed, but most clincher rims these days are made with a channel to make tubeless mounting easier. None of them prohibit the use of tubes.

[brian51574]

I had two blow-outs (loud, very loud) on my Zipp 404 with 2 different brands of Tires (Ultremo ZX 25 and Evo Corsa 3). It took a while but I finally figured out that tire pressure was the cause.

I recommend you check your tire pressure with a secondary pressure monitor. I discovered that my floor pump was off by 15PSI. So when I thought I was pumping to 120, I was actually filling the tubes with 135PSI. On both blow-out occasions, the incidents occurred on summer humid days and at high speed. It is logical to assume that heat will cause an increase in tire pressure. Both the Schwalbe Ultremo and the Vitorias have extremely high thread and soft rides. Also, 135-150PSI is way over the maximum PSI amount. Hence - BOOM!

This never happened, luckily with the GP4000s because the compound is a bit harder. As a result, I am only using 4000s and Continental Attack/Force and double checking my PSI and inflating to 110.

I hope this helps.

[tinozee]

WMW - I do notice the center channel and I have setup all kinds of wheels tubeless and ghetto tubeless. It's not rocket science at all. I just have a big roll of stan's rim tape and a compressor, and can setup pretty much any wheel tubeless, mtb, cx or road.

This thread is about Stan's 340 tubeless rims though! I'm just sayin, stan's tubeless rims with hutch tubeless tires work *f##k* awesome, and it shouldn't be confused with using clinchers and tubes on them (eww).

[njspanasonic]

I wanted to add my personal experience regarding these rims. I have been running them with tubes and Conti GP 4000s, Vittoria Open Corsas, Shwalbe Ultremo for the past 2 seasons, no problems with tires coming off the rims whatsoever. I had the first edition Alpha 340s which I crashed a few times racing and small cracks developed around the nipples from the uneven tension. Stan's warrantied those and version 2.0 has been flawless besides the somewhat sloppy rim weld that i simply sanded down a bit. Just set them up with IRC Formula Pro Light and dropped about 150g. Using 1oz of sealant per tire. This is my favorite setup yet ! Dropped the pressure 10psi per tire, smooths out the ride with great handling and fast rolling feel. Running 90 psi front, 95 psi rear. Just did a race where I slammed a few potholes harder than I ever have before, a guaranteed pinch flat if running tubes, NO issues with the tires or rims from the impact which I was seriously impressed by. I can't wait for more tubeless options from the big names, I'm sold.

[LouisN]

Installed with Veloplugs, Veloflex Corsas 20 mm (on older version rims) and didn't experience anythig wrong in two years...

Louis

[WMW]

Just set them up with IRC Formula Pro Light and dropped about 150g. Using 1oz of sealant per tire. ... Just did a race where I slammed a few potholes harder than I ever have before, a guaranteed pinch flat if running tubes.

Off topic, but I couldn't resist. Those are very expensive and fairly light for tubeless... but they are still ~250g per tire, right? Plus 30g for sealant makes it 280g. I run tires that weigh between 150g and 210g with latex tubes that are between 50g and 70g. So even worst case, no heavier.

Latex tubes are very resistant to pinch flats too... never had one in at least 40k miles of riding them. Hit a pothole once that dented both rims but the tubes were fine.

Back on topic, many people have experienced no problems with tire retention both with tubes and without. Unfortunately, some have experienced tires blowing off with either setup, and it seems to be more than usual.

[thprice]

I have ridden stan's alpha for a few years now, no blowouts have been experienced.
340 series 1 on the front, veloplugs, 23mm Conti 4000s at 90 psi
I'm a little harsh on rear wheels so after cracking the spoke holes on the original 340 rear rim, went to a 400 series on the rear, veloplugs, 25mm Conti 4000s at 90 psi

[bikerjulio]

My OP on these is 2 1/2 years old now. 1st gen. http://weightweenies.starbike.com/forum/viewtopic.php?f=3&t=97281

Still riding them with the PR3's and really no problems at all. I run around 75# F and 90# rear. My only complaint was the joint quality which I can still feel on braking.

[tinozee]

Still have three sets of wheels with 340 rims. They are all used for rain riding and holding up fine. But I use tubeless tires with a carbon bead with them, so there will never be a blow off or any worry about one. Gee.

[kulivontot]

I think the lessons here are:
Pump less than 100PSI
Use tubeless if possible, preferably Hutchinson
Potentially watch out for schwalbe and gp4000's
Definitely use Stan's yellow tape, 2 layers

[phazon]

I'm running Bontrager R3 TLRs - no problem so far in a couple of thousand km. I would second the braking feel, the actual braking is great, but definitely not the smoothest

Otherwise excellent wheels