Author Topic: Jim (a non-racer) and tubeless MTB tires  (Read 1645 times)

jim-ratliff

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Jim (a non-racer) and tubeless MTB tires
« on: May 30, 2012, 01:55:27 pm »

As many of you know, we beat this topic to death last year.  However, Lynn and I recently upgraded the wheels on our Mountain Bikes, which led to some playing around.  First of all, here's where I started.

1. My primary goals are avoiding dealing with flats (either pinch-flats or real-flats) with as little rotational inertia and rolling resistance as possible.
2. What the racers are riding and the pressures they are using has little relevance to me.  They are wanting to win races, I'm not wanting to fix flats in the middle of the poison ivy and mosquitoes, and I certainly don't generate enough power that i have trouble getting it to the ground.
2. I didn't want to deal with the hassle of Bushwacka's ghetto tubeless or with Stan's approach to making regular wheels tubeless.  No educated reason behind this other than the requirement for a "high-volume" air source to seat the tire, but it just didn't excite me.
3. I bought a slime tube last year and tested that on the front of my mtb. No flats last year, but I pinched it when we changed wheels this year and it didn't heal itself (and it was a small hole). Discarded Slime Tubes as a viable way of preventing flats.

So once we decided to buy wheels that happened to be Mavic UST compatible, I decided to play with tubeless. The two tires we are using are the Continental X-King RaceSport (me) and the Kenda Karma (Midwif). The Karma is a 460 gram tire with "very supple" sidewall that seems to work well for her.

All of the X-King's are tubeless compatible (meaning they have a tubeless bead) but only the UST model is truly tubeless. The Racesport and Supersonic have a lot of web traffic about how porous the sidewalls are, but that they seal quite nicely with Stan's.
  • X-King 2.2: 3 plies / total 84 tpi / 580 grams
  • X-King Racesport: 3 plies / total 180 tpi / Black Chili Compound  / 490 grams
  • X-King Supersonic: 3 plies / total 180 tpi / Black Chili Compound / 460 grams
  • X-King Protection: 4 plies / total 240 tpi / Black Chili Compound / 570 grams
  • X-King UST: 3 plies / total 330 tp / 780 grams
And then I realized that, even with tubeless, I was still going to need Stan's (or similar) in the tire to deal with punctures. And if that were the case, then why lug around the 290 gram difference between the UST version and the RaceSport version?  They would both need the Stan's anyway.

Test A. I mounted the front tire tubeless. I found that the CO2 cartridge inflator I carry for my road bike does a great job of inflating the tubeless tire. I stuck the tire in a sink full of water and was amazed (but not surprised) at the sidewall porosity -- I was surprised at how quickly the Stan's sealed everything up. The next morning I still had an inflated tire, I went for a 12 mile ride that evening and it worked fine. I lowered the air pressure some, but any difference in the ride characteristics was minimal. I pronounced that a successful test; tire + Stan's was 30 grams less than tire with tube and I felt that it would seal any punctures.

Test B. I did the same with the rear tire.  This was a little bit easier, because I was careful to only unseat the bead on one side (to get the tube out). After inserting the valve stem and pouring in the Stan's, I manually worked the loose bead closer to the rim.  I managed to inflate this one with just the hand pump (and immediately patted myself on the back).  Did the same routine with water in the sink, this tire didn't seal up quite as well.  Next morning it was flat -- the next evening I aired it back up and rode the neighborhood slowly figuring that was a good way to circulate the Stan's.  By the end of the ride it seemed good, and next morning it still had air in it.  WOW, I'm a genius.  Lynn's bike happened to still be down here, her tire is next.

Test C. I did the same with Lynn's front tire. Her tires are not UST anything. Did the same trick when I removed the tube of not loosening the bead on one side of the tire. Had to use the cartridge inflator for air volume, but the tire popped right into place and I inflated with the hand pump. Stuck the tire in the water. Her sidewall (on a tire that is now three years old) didn't leak air at all like mine -- however, her tire did have a lot of leaks around the bead. These didn't seal until after I rode the tire around some the next day.

Real World Test. This past weekend we went riding in the 14,000 acre Ten Mile River Boy Scout Camp. Started out on level asphalt getting to the camp, and rode a loop that ended up with us coming down a long hill on asphalt at 27 miles per hour. In between was lots two lane rock covered jeep trails that the hunters and Boy Scout maintenance trucks use.  I would still say that I really never felt much difference in the performance of the tires, except that we both found ourselves bombing down some sections at 18 miles per hour with enough control to pick which parts of the road we wanted to ride on (avoiding the mud and standing water in lots of sections of the trail). That may show a better level of control than before, in places where we have used the brakes to slow down in the past. (or maybe we are just getting more "one with the bike").


CONCLUSION: After the ride and then sitting two days, my tires were way down on pressure, but I'm ok with pumping them up before each ride (we have to do that for the road bikes anyway). The sink full of water seems to confirm my guess that the flexing of the sidewalls (especially over the really rocky trail) resulted in some really slow sidewall leakage when the tire was just sitting (no sealant being spread around). 
I'm pretty pleased with the results thus far. In fact, I'm planning on ditching the air pump that I carry on my bike -- but I might add a CO2 inflator to my back pack.


CONCLUSION 2: I think there may be building acceptance of tires that are tubeless ready but that rely on the sealant to truly hold air. I've seen that in Continental and WTB and Svend was mentioning the new SCT (Sealant Compatible Tubeless) categorization for Kenda tires.



« Last Edit: May 30, 2012, 03:34:02 pm by jim-ratliff »
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bushwacka

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #1 on: May 30, 2012, 07:34:01 pm »
the real reason to run tubeless are these.

more supple easily more controllable ride that roll faster and has more grip. You do not have to be a racer to like that. I would mount them on any bike that is never going to be raced I am not good enough to ride on a tubed tire.

with that said you will start to notice a difference riding rougher terrain and you have more grip.....but most people have gotten so use to the shitty grip of tubed tire setups that it can take some time to take advantage of the new grip that there but unuseable untill you take advantage of it....and you need a lower pressure than a tubed tire to make the difference.

also IMO overall weight is pretty meaning less. If lighter was faster we would all be running fully rigid fixied gears with no brakes and cross tires.

jim-ratliff

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #2 on: May 31, 2012, 07:15:07 am »
also IMO overall weight is pretty meaning less. If lighter was faster we would all be running fully rigid fixied gears with no brakes and cross tires.
If lighter isn't faster, then why do racers use bikes made of aluminum, titanium, or carbon.
Obviously, the weight "penalty" associated with multiple gears and with being able to stop pays for itself in other areas of performance. But that doesn't make weight meaningless, and people still pay to have those components as "weight effective" as possible.
I will say from first hand experience that lighter makes it easier for me to pedal up the hill.


And, IMHO, not wanting to have to deal with flats on the ride is a very valid reason for riding tubeless.  Your reasons may differ, obviously, but that doesn't make your reasons the only "real reasons".   8)
« Last Edit: May 31, 2012, 09:31:15 am by jim-ratliff »
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Svend

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #3 on: May 31, 2012, 05:20:28 pm »
Jim,

I'm just curious -- have you ever actually had a flat on your mtn. bike? That is, in your antediluvian pre-tubeless days?  ;)  The reason I'm asking, is that you seem very concerned with flats and not having to fix them, hence one of the two main reasons for going tubeless.  I have been mtn. biking since 1989, very actively for the first 10 years, now back at it again after a hiatus.  Nevertheless, I have had hundreds of days out in the woods, and have only ever had two flats, and that was about 12 years ago on my old rigid bike with cheap tires.  It was caused by a hole in the sidewall of the tire from the rubbing of an out of alignment brake lever, but not by a pinch flat.  I presently run my tires at 35 to 40 psi, which is not super hard, and hit all manner of obstacles with nary a pinch flat in sight.  And I'm about 50 lbs heavier than you! FWIW, no one else in our family of riders has ever had a pinch flat.  Never....   And their tires are down around 30 to 35 psi, being that much lighter than I am.

What I'm trying to say, is that your fear of pinch flats might be a bit overblown.  In other words, don't worry so much, and just go riding.  I'm sure that as long as you keep your tires (with tubes) above, say, 35 psi, you will be fine.  And I hear what Josh is saying about grip and suppleness, but unless you are on some really rooted, rocky trails, you will not have any issues with grip on firm hardpack.  Besides, you've got a nice light full suspension bike to absorb the bumps and give you a supple ride, and high quality tires which I'm sure will give you good grip with or without tubes.


jim-ratliff

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #4 on: May 31, 2012, 07:24:38 pm »



Yeah, I did have apinch flat last year. Fortunately, Lynn and I were riding together and she rode back and got the car while i walked the bike out to the road.  But that was before I started carrying a spare tube and bought a pump.


But I also will admit that much of this is just me deciding to play with tubeless.
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bushwacka

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #5 on: May 31, 2012, 07:54:24 pm »
Jim,

I'm just curious -- have you ever actually had a flat on your mtn. bike? That is, in your antediluvian pre-tubeless days?  ;)  The reason I'm asking, is that you seem very concerned with flats and not having to fix them, hence one of the two main reasons for going tubeless.  I have been mtn. biking since 1989, very actively for the first 10 years, now back at it again after a hiatus.  Nevertheless, I have had hundreds of days out in the woods, and have only ever had two flats, and that was about 12 years ago on my old rigid bike with cheap tires.  It was caused by a hole in the sidewall of the tire from the rubbing of an out of alignment brake lever, but not by a pinch flat.  I presently run my tires at 35 to 40 psi, which is not super hard, and hit all manner of obstacles with nary a pinch flat in sight.  And I'm about 50 lbs heavier than you! FWIW, no one else in our family of riders has ever had a pinch flat.  Never....   And their tires are down around 30 to 35 psi, being that much lighter than I am.

What I'm trying to say, is that your fear of pinch flats might be a bit overblown.  In other words, don't worry so much, and just go riding.  I'm sure that as long as you keep your tires (with tubes) above, say, 35 psi, you will be fine.  And I hear what Josh is saying about grip and suppleness, but unless you are on some really rooted, rocky trails, you will not have any issues with grip on firm hardpack.  Besides, you've got a nice light full suspension bike to absorb the bumps and give you a supple ride, and high quality tires which I'm sure will give you good grip with or without tubes.

I would argue 35 psi is too high for anyone riding XC I run as low as some high teen sometimes on a full suspension bikes. The deal is most people do not the benefit because well they have never tried it.  Ignorance is bliss. Even on smoothest trails ever the gains in rolling restiance and grip are worth it, it makes it easier to ride faster or much easier to ride at the same speeds your riding at pre tubeless.  Off course you would never get a flat running a tubed tire near 40 psi, but that a lame comparo because 40 psi sucks. I am not good enough to ride 40 psi on any trail.

Gerry Pflug recently rode a 2.4 ardent(a 1000 gram tire plus sealant) at 14 psi in 78 mile mountain bike race to single speed win. I am sure he beat tons of people who had weight weenied out tire setups that actually rolled slowed and gripped less.




Svend

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #6 on: May 31, 2012, 08:31:43 pm »
Josh, I totally understand what you are saying, and I am not disagreeing with you.  But the point I was trying to make to Jim, was that worrying about pinch flats should not be a reason to go tubeless.  Unless you are riding across sharp rocks, or jumping off 10 ft. drops, or hitting gnarly roots at warp speed, pinch flats are just not an issue.  I have not ridden the trails in Virginia where Jim rides....maybe he rides in some way gnarlier stuff than I do.

OTOH, if Jim wants to go tubeless, then do it for the performance benefits that you are talking about.  It sounds like the process is easy with the new UST wheels that he has.  If it improves the ride, then by all means go for it. 

One of these days, when I wear out my present Slant Six tires (which are not sealant friendly, according to Kenda), I will get some UST or sealant-compatible tires and try tubeless too, as my rims are tubeless ready.  In the meantime, if, as you say, ignorance is bliss, then I must be very ignorant, because I am having a great time on my bike this year.  That machine is just humming a sweet tune lately, and I am having no trouble navigating the single track in our local woods. 

BTW, I just put a new flat, wider handlebar on the Paragon and had my first ride with it tonight.  Great improvement in handling.  I can really grab the bike by the scruff now and make it do anything I want.  Between that and the new tires I put on last autumn, I've finally got it handling like an agile 26er.  Love it!

« Last Edit: May 31, 2012, 08:48:22 pm by Svend »

Svend

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #7 on: June 01, 2012, 07:36:40 am »
Jim, do post back here once you have more time on the trails, and let us know if you notice much difference in performance.  You being a critical and objective thinker makes your opinion of great interest to me.

Did you get much time on the trails this spring prior to going tubeless? Do you think you can do a good before-after comparison, based on recent rides?


Svend

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #8 on: June 01, 2012, 07:55:49 am »
Jim -- one more comment:  Josh has a point about not going overboard on the lighter-is-better thing.  You may end up spending a lot of time and money lightening your ride, but then end up making the bike too fragile to handle rough terrain or more aggressive riding.  Lighter components sometimes means easily broken.  I have seen guys carrying their super-light race rigs out of the park with a wheel folded like a pretzel, or some other component snapped right off.  There is usually blood involved, too.  :P

I know you and Lynn come from a long background of road riding, and may feel that light weight is paramount, but trying to get your mtn. bikes down near the weight of your road bike may be unwise.  IMO, it's better to try to find that balance between durability and strength, which gives you confidence that the bike can take a bashing and still keep the rider intact, and lighter weight for an easier pedaling effort.  It's no fun having to carry or push your bike through a rock garden because you're afraid of blowing a sidewall or denting a rim, all while wearing hard-soled bike shoes.  Tougher tires and other components may be a bit heavier, but you will have more freedom to have fun and not fear the rocks.  Besides, blasting through a rock garden on a full suss bike is a hoot.  Just don't fall!  :o

Hope you get out in the woods this weekend.  It's supposed to rain here until Monday (figures  ::)) so unless there's a break in the weather, I'll be riding in my daydreams.
« Last Edit: June 01, 2012, 08:01:08 am by Svend »

Svend

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #9 on: June 01, 2012, 09:03:59 am »
Jim, here is a video that shows a neat way of mounting a tubeless tire without a compressor.  Sounds like your method is working well for you, but perhaps the little trick shown here will make it even easier.

http://www.mountainflyermagazine.com/view.php/macky-franklin-blog-tubeless-setup-without-a-compressor.html


jim-ratliff

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #10 on: June 01, 2012, 11:17:38 am »



Svend:  Thanks.  I was doing something similar with my fingers, just pushing the tire out to the edge of the wheel.  Never thought of using a tire lever to pull the tire out to the edge.  Good idea.  Thanks for posting.
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bushwacka

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #11 on: June 02, 2012, 06:26:54 pm »
it weird that i show up to races/rides better equiped than the giant team techs.

http://www.amazon.com/Shinn-Fu-Co-W1010A-10GAL/dp/B000LNUFRO

with this guy I can seat and tire that is going to seat. Best way to change tires quickly at an endurance lap race.

jim-ratliff

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #12 on: June 02, 2012, 08:38:15 pm »
That is a very good idea.  I had been thinkimg tank with compressor, but the tank is all you need. Thanks.
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Svend

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #13 on: June 02, 2012, 08:51:19 pm »
Cool! That is something Jim could strap to his back to take on a trail ride.  8)  He did say he'd ditched his hand pump, didn't he? And if he needs a boost up a long hill, just point the valve rearward, and open 'er up.

Hey Josh...question for you:  is it OK to run tubeless on the front, but tubed on the rear? Or will that invoke some weird handling quirks? I want to put a wider tire on the front for better float through some of the many sand and gravel patches that we have here.  If I don't hit those at a fast clip, I'm sunk....literally.  I want to keep the existing Slant Six on the rear, but Kenda does not recommend sealant for that version (last year's), so can't go tubeless on the rear. 

For a new front tire, as the Slant Six is working extremely well for me in our smooth hardpack terrain, and the new versions are now sealant-compatible, a 2.2 version of this tire is my first choice.  Or a 2.2 in. Ignitor or Saguaro....we'll see.  But since I will be pulling the non-sealant-compatible Slant Six off the front, I have an opportunity to try tubeless as replacement and see how it works.  Just concerned that staying with a tubed tire on the back will not work well.  Let me know what you think....  Thanks.

« Last Edit: June 02, 2012, 08:57:29 pm by Svend »

Liam

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Re: Jim (a non-racer) and tubeless MTB tires
« Reply #14 on: June 03, 2012, 11:30:42 am »
The only real down side to very low pressures is excessive rim damage over long time use in rough areas.   Since I started riding tubeless several years ago, I've noticed lot more scuffing around the surface of my rims.  That said, I haven't had any truly significant damage.

35psi is way too high for mountain riding these days.  Depending on the tire and rim I find 25-28psi to be just about perfect...that was even with a tubes.  A little lower in really slick technical trails and Much lower in sand or snow.

I have run combo's of tubed on rear and tubeless on front (and vice versa) which was usually the after effect of a stan's blow out on one tire or the other that I on-trail fixed by popping tube in and continued to ride that way for a few weeks or until the tire went out.

I never noticed any counter acting effects of riding with one tired tubed and the other tubeless.

Kenda- all kenda's ride a lot better in a stan's set up ( I think the Nevegal with tubes is one of the worst tires ever made, but I really like it tubeless).