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Discussion Starter · #1 ·
I was up at Whistler yesterday putting my 7point7 through it's paces. It took me a while to get used to the bike on the A-line jumps but after 3 runs I was hitting all the jumps with confidence. The bike rips, the forks could be a little plusher, but the back end for me was more than good enough, the only time I felt it was getting overwhelmed was doing Hornet into lower a-line at Mach 4, but then again what wouldn't have a hard time with those bumps, :eekster:

Anyway my only beef was with the tires/wheels.

Firstly the tires: now the theory behind tubless is running lower pressures as there's no tube to worry about pinching. This means that the sidewalls can be more supple too. Now the Highrollers fitted to the 7.7 as standard are good for riding the shore and grip great in that situation, however once the speed picks up they don't work so well.. the lack of stiff sidewall means that the tire rolls over more when giving it some stick in the corners. At more than one point yesterday I burped the tires pretty good and did it so bad one run that I had to stop to add pressure. I had to really up the pressure in the tire to stop it doing this and that kind of negates the advantage of tubeless. Are other UST tires better for this? Michelins? I'm a hard heavy rider and so I'm sure I give the tires a harder time, I like UST so far apart from this problem and don't want to have to resort to tubes again to get tires that have that stiffer sidewall... any suggestions?

Secondly the wheels, specifically the rims. The 823 rims are working out fine so far, but yesterday I lost spoke tension and found out that it's the screw-in spoke supports that were coming loose. Anyone else seen this? Looks like I'll be going at them with the locktite, but still, it's not a great scenario. Thankfully I was able to fix it on the hill and tweak the wheels true again.

Other than that a great day in Whistler with the bike inspiring me to rip it up. What more can you ask?
 

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Jon,

Are those tires UST? I'm assuming they are, like the ones that came on the bike. I believe Maxxis UST is somewhere between single ply and double ply, at least that's what i've "heard." This might explain the sidewall folding over.

You might want to try standard Maxxis 2 ply tires filled with at least two cups of Stans. This is what I normally use. (actually, 2 ply standard 2.7 in front, UST 2.5 in the rear since I do a lot of trail riding).They mount very easily, as long as the bead is clean. Some soap bubbles also assist in getting the bead to "pop."

As far as Michy goes, those 32s are GREAT tires. They're expensive, heavy, and the 2.8 MAY rub on that Sherman just a little bit. I felt the sidewall on that tire was much stiffer than the Maxxis. I use stans, but a little less, in the Michy's. I use a mich 24 (i think that's the model) 2.5 on the rear. Not so impressed with the tread, but there are ways to cut them for your dirt.

What pressure are you running?
I've "heard" that a lot of folks run too little pressure when using UST. Supposedly, the idea is that you can run just a little bit more pressure so the sidewall stays firm, but without the tube inside you still get the tread to conform to the surface and absorb little bumps and stuff. I run about 22 - 25 psi upfront and about 28 rear. I did notice the tires getting squirrly under 20 psi.

I LOVE UST!!!:thumbsup: Don't give up on it!!!

Oh and the wheels,
I haven't used any other UST wheels before. But, when mine were new, the nipples and the eyelets did work themselves lose a few times. This is supposed to be normal for new wheels. Haven't had a problem since.

Whistler... lucky you!
I should be up there next summer for part of my honeymoon.
 

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www.derbyrims.com
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First set of tubless for me

jon_boy said:
Firstly the tires: now the theory behind tubless is running lower pressures as there's no tube to worry about pinching. This means that the sidewalls can be more supple too. Now the Highrollers fitted to the 7.7 as standard are good for riding the shore and grip great in that situation, however once the speed picks up they don't work so well.. the lack of stiff sidewall means that the tire rolls over more when giving it some stick in the corners.
I have the same problem with my first tubeless set up of tire rollover in corners. Also I have to add air nearly each ride due to the bead burping air while riding or very slow leaking over night.

Looking for suggestions for a lighter weight good climbing and handling 2.2.5 - 2.4 size, with stiffer sidewalls for tubeless using lower pressures.

Currently on my first set of tubeless, I'm using Stan's with a non-UST tire (new version Hutchison Python 2.3) on Mavic UST (3.1x) rims. I definitely won't get these tires again, they grip pretty well with a very low rolling resistant softer tread with square profile, but suddenly loose traction when leaned on, and wallow sideways if the air pressure isn't pretty high. I like the more predictable drifting rounder profile tubed tires I used before, Mutanoraptor 2.4.

But the Mutanos are too tight to mount on UST rims with less than 60+ pounds of pressure using tubes (almost impossible to lever onto WTB's own brand rims too!).

- ray
 

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Discussion Starter · #4 ·
Solar, yes they are UST, the standard fitment on the 7.7 05 model.

So am I right in understanding what you wrote... I can mount a standard Highroller, with the downhill sidewall to my 823 UST rim, fill it with some Stans sealant (which I already have) and just pump it up to pressure? If so that's great. I was running an experiment with my rear tire with 3 cups of Stans in and none in the front... my obvious conclusion from that was to put Stans in the front and see if that works.

I think I had the pressures quite high, certainly higher than I ran last year with a traditional setup. I had around 35psi front and rear to start, it's the back tire that gets the brunt of the abuse, especially when drifting slightly into bermed corners.

I have an Intense 909 tire in my workshop that I could give a try, either that or get another set of wheels for 'Whistler abuse' and put some stiffer side-walled tires on those.
 

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Yeah, try the standard Maxxis DH tyres with stans.
You don't need rim strips or anything else.

If you have trouble getting them to pop on the bead, put some soap bubbles on the bead and try putting the wheel on a more horizontal axis rather than straight up and down.
Also, be sure the stans coats the entire inside of the tire before pumping.
I use a floor pump, but I'm sure a compressor will make it even easier.
I usually air em up to about 50 psi and shake the wheel around so the stans spreads evenly. Use the soap bubble to find leaks and rotate the tire so the stans coats that area.
That's it!

I hope it works for ya.
 

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Just another FOCer
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Yep, happened to me on my rear wheel. Sweet wheelset, too bad they are factory built. My LBS also recommended loctite.

I second the use of Stans, even with UST tires on the 823s. I've never had a burp running Maxxis UST or Michelin UST tires.

Have fun, we are all jealous of you,

Winston

jon_boy said:
Secondly the wheels, specifically the rims. The 823 rims are working out fine so far, but yesterday I lost spoke tension and found out that it's the screw-in spoke supports that were coming loose. Anyone else seen this?
 

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M070R-M0U7H FR3NCHI3
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Oh man…UST is a touchy subject for me too.

My first beef with UST was rims. When I first adopted Tubeless on my DH bike two years ago I was constantly flat spotting those D3.1 rims. In less than two months I went through 4 rear rims. As you know Mavic UST wheel are pretty tedious to build – so that right there was enough to make me switch back to tubes.

Last year I decided to give UST another try! Well just like JB I keep on burping my rear tire – and just to be clear, I was running a UST rim and UST tires (e.g. Michies). I got tired of getting Stan’s sealant on my rotors and having to check my rear tire after every run. So back to Tubes I went.

About mounting non UST tires on UST rims…well last year I had a fiend come over and tried mounting a non UST maxxis tire on his Mavic UST rim. We used stans and my air compressor.

Well guess what...While trying to get the bead to seal, I had the tire blow off the rim right in my face - I thought for sure I had lost my finger, right eye and ears!! holy crap!!! Stan's all over my face/garage and the rim literally flew to the back the garage while the tire flew outside. Even an hour after I was still dizzy.... My right eye hurt for days...it got a powerful spray of Stan's when it blew. It scared the livin' sh|t out of me!! I'm surprised the neighbors didn't call 911 from the noise it echoed through the neighborhood!!

Needless to say I didn't feel like trying to mount it again after that...

SO…last week I decided to take the 819 UST wheelset off my 5-Spot (which I ran with tubes BTW) and mount those on my MkIII. I also decided to mount some UST tires just to try out – thinking “ hey, it’s a trail bike so I shouldn’t have issues with burping”. Well think again! On my first ride I burped my rear tire coming down this fast rocky section. I was pretty pissed at that point. Then my riding bros start telling me “dude that’s because you don’t run enough air in your rear tire!” Heck, I had like 32 psi’s in there (in a 2.3 tire)! what is the point of running tubeless if I can run somewhat of a low pressure – and I don’t consider > 30psi low.

Anyway…I’m done with tubeless for any back tire. But I’ll admit that I don’t mind it on the front. I’ve never had any issues with any front UST setup!

I also like to change/test tires quite often. For me that’s another downside to tubeless – changing tires is a messy job!

Okay enough ranting ;o) time to run to a meeting…cheers!!

- Luc
 

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Damn Luc, that's one crazy story. Makes me glad I don't have a compressor!

I guess I'm pretty fortunate w/ my UST experience!
Of course, the maxxis, michies, and 823s are the limits of my experience.

I can only think of three times that the tires have burped air: front tire twice, rear once.
The front tires burped by catching some edges in a rock garden
Rear tyre burped from a sideways landing...

This leads me to the following possible conclusions:
1. I'm one hella smooth of a rider (sure:rolleyes: )
2. I'm not riding hard enough (maybe)
3. I'm just one lucky mofo (most likely)

If a UST tire blew off the rim and into my face, or was constantly burping I'd be skeptical too.
 

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I look at it this way... I'm sitting here reading that even with what amounts to the most expensive UST rims and best possible combination of products money can buy, and you STILL might have on and off issues with tubeless, I'm COMPLETELY sold on staying with tubes.

I'm running my ghetto WTB Dual Duty rims with Maxxis downhill tubes and 2.5" or 2.7" 2ply Maxxis tires. This past weekend at a downhill race here in the east race day saw 6 inches of rain fall on the couse which turned into a swamp, a river, and a rocky mess. I surived a couple practice runs at a nice intermediate pace with....wait for it....12psi in my tires.

The tires were so soft that when I got to the bottom people thought I had flatted. When I stood over the bike and pushed on the tire with my palm I could squish it enough to touch rim with my hand. Now I'm not saying this combo was great for handing or longevity of wheel/tube/tire but hey it didn't pinch flat and I'm 240 pounds of unsmooth rider.

Next time while I'm on the lift with my bike I won't get bored and let more air out thinking the tire feels hard. ;-)
 

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I'm still running my stock High Roller UST 2.7 on the front of my 7point without a tube. I'm on my 3rd rear tire and I've since gone to a tube. Last year at Whistler I destroyed both of my 823 rims. I was running mid-20's for PSI on both wheels and I forgot to check my spoke tension after every run. I still cannot get those stupid nipples to stay tight. Loctight helps for a little bit, but it doesn't take long before you have to tension some spokes. I talked with a few shops at Whistler that claimed they saw those tubless-nipples come loose all the time. I would have to tighten nipples between almost every run. Granted, I wasn't puting the wheel in a truing stand and kranking down on them, but I would still have to go through them constantly to keep them from falling apart. I had plans to run my new rear tire tubless on my 729 rim w/stan's rim strip, but I ended up getting a Kenda Nevegal. I've tried in the past to get those tubless. They leak from the sidewalls. Anyway, even running more PSI with tubless, I think you still get better traction than with tubes--to a point of course.
 

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Discussion Starter · #11 ·
So there's good and bad experiences (and Luc's sound pretty bad). I'm not going to give up hope just yet, I'll stick some Stans in the front tire and so how it is at Whistler next time.
To be honest they've not been too bad when riding the north shore in Vancouver, depends on the trails being ridden. The lower speeds might have something to do with it. The thing is that when you ride that bike at Whistler and open it up (as it begs to be) the UST system doesn't really hold up. You want to pin it through rocky sections where you might glance off a rock or two, you want to drift the rear into the berm, it's how the riding is there. I'm just thinking that with a stiffer sidewall there will be less 'burping' going on and that'll only help the situation, thus I will give a standard tire on the UST combo a try, I will not use an air compressor to pressurise it though!
The question I have is are the pro's using UST extensively? I can't see them risking having a tire loose pressure like that over a race run, so if they are using UST rims/tires what's the trick that they are employing to make it work?
 

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derby said:
I have the same problem with my first tubeless set up of tire rollover in corners. Also I have to add air nearly each ride due to the bead burping air while riding or very slow leaking over night.

Looking for suggestions for a lighter weight good climbing and handling 2.2.5 - 2.4 size, with stiffer sidewalls for tubeless using lower pressures.

Currently on my first set of tubeless, I'm using Stan's with a non-UST tire (new version Hutchison Python 2.3) on Mavic UST (3.1x) rims. I definitely won't get these tires again, they grip pretty well with a very low rolling resistant softer tread with square profile, but suddenly loose traction when leaned on, and wallow sideways if the air pressure isn't pretty high. I like the more predictable drifting rounder profile tubed tires I used before, Mutanoraptor 2.4.

But the Mutanos are too tight to mount on UST rims with less than 60+ pounds of pressure using tubes (almost impossible to lever onto WTB's own brand rims too!).

- ray
My question isn't on the tubeless tires but in regard to the Cinder tires that came on the MKIII expert. They perform well for all mountain trail riding but while XC in a sharp flat turn was left sliding in the dirt. The Cinder 2.25 square type profile seem squirrelly once you get to far on the edge in flat hard pack with loose top layer. Had been running Continental gravity and verticals on previous MB nothing great but never left me sliding in the XC turns. I do like the Cinders better for the grip on the mountain though. Keeping in mind mountain trail is the main reason for the ride and XC to get there and back. Any tire suggestions?
 

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Discussion Starter · #14 ·
I'm still running the stock ones but I put stans in the front tyre and re-seated them. I've ridden the shore a few times now and haven't had to top the air up as much as I was before. I've yet to ride at Whistler again and see how the stans helps with the air loss there, however it won't change the fact that the tyre just isn't as stiff as I would like. We'll see what happens.
I've been too busy building a new bike and upgrading the 7-point to think about the tyres much.
My upgrades won't touch Auk's but they'll improve the overall 7point experience. :)
 

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Discussion Starter · #16 ·
Yes, upgrades, brakes and fork for now and yes, still single crown.

Okay here's a question I'm toying with... I don't mind the current cranks but the BB is worn and needs new bearings. The usual ISIS story. I'm thinking of cutting my losses and going with the saints. I have a set on another bike and like the ease of installation and they are sturdy as hell and IMO look good. Do I pick up a set of Saints for the 7point? I know Auk has some, anyone else?
Is it a pain to set the DRS up with the outboard bearings?

Jon.
 

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I don't think I ever mentioned that my 06 7.3 came with a Truvativ Howitzer Team BB. The spec said the lower end XR model but hey I'm not complaining if they gave me incorrect parts and they were in fact better!

That said, I'm a big fan of these external BB's now that I've thrashed bikes with both ISIS and external. And the cranks couldn't be any easier to install, just put the BB in the bike and put each crank on with the single crank bolt in the center like the old ISIS. Good stuff.
 

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jon_boy said:
I

Firstly the tires: now the theory behind tubless is running lower pressures as there's no tube to worry about pinching. This means that the sidewalls can be more supple too. Now the Highrollers fitted to the 7.7 as standard are good for riding the shore and grip great in that situation, however once the speed picks up they don't work so well..
here is your problem......................

high speeds you need more air.......if you go slow in tech section then lower your air (I never drop the air for more traction.....lowest I run is 22 in the front and back the same........but usually run 28 to 32psi on everything...front tire
 

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M070R-M0U7H FR3NCHI3
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SHIVER ME TIMBERS said:
here is your problem......................

high speeds you need more air.......if you go slow in tech section then lower your air (I never drop the air for more traction.....lowest I run is 22 in the front and back the same........but usually run 28 to 32psi on everything...front tire
but you would be amazed that some people even consider 30psi low....:confused:

I run pretty much the same psi for all my bikes...between 26-28 for the front and between 30-32 for the back and even with that amount I was burping the back tire.

Recently when I tried it on my XC bike and burped the back tire my bro was like "dude you don't run enough air in your back tie - you got to run at least 35-40" Maybe it's just me, but 40psi's just doesn't feel right…
 
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