[PoKev]

Let me preface this thread by mentioning that yes it could have been placed on the Wheels & Tires board, however, I feel the discussion here amongst my Turner brethren will be more engaging, enlightening and at times very wity .

I'm sitting here at the new computer listening to some jazz and thinking about the last few rides. I recently put my other set of wheels on with the smaller high volume tires and lowered the pressure to 28psi (UST) and rode a couple of my favorite loops. The front tire tracked solidly as I expected, the surprise was how well the rear dug in and gripped whether cornering or climbing. Most climbs here consist of loose rock and/or roots and I've dealt with 2.25 - 2.4 tires breaking away (maybe in part due to my riding style) and then hooking up again, usually run at 30 - 31 psi. I ran a 2.0 Python on the rear and noticed no more slippage than normal and in a few sections there was nothing but traction.

Mind you, this is not scientific in nature, just a discussion of whether a big tire is necessary for most riding. Around here it's mainly tight Midwestern singletrack so we don't face many high speed sweeping curves that may be covered with sand/gravel. We also don't encounter many jumps/drops, so the extra absorbtion that a large tire would provide is not always needed. The weight difference/roling resistance is not noticed much until there's an extended climb.

Is it the psychological confidence gained from looking at a large tire that makes me want to continue the search? Or, will my 5 Spot be happy with the current Roll-X/Python (f/r) combo.........................BTW I just received a Spider 2.1 UST and am waiting on a Blue Groove 2.1 UST to run on the other set of wheels.

Large tires, smaller tires.................is it the tire size or the pressure? I'm running UST so I can go into the upper 20's with no adverse effects (I weigh ~185). Whaddya think???????????

Peace............

Kevin

 

[Jm.]

That's nice, but if I run my tire pressure that low I dent my rims, which tend to be pretty expensive. That's one area where I see no benefit to UST/tubless. Lower the pressure=dent the rims, at least for me.

 

[PoKev]

That's nice, but if I run my tire pressure that low I dent my rims, which tend to be pretty expensive. That's one area where I see no benefit to UST/tubless. Lower the pressure=dent the rims, at least for me.

What pressure do you run? And do you find large tires or small to be more effective.

 

[Jm.]

What pressure do you run? And do you find large tires or small to be more effective.

at least 40, sometimes a good bit more, most times no less. Anything in the lower 30s is risking a dent, and anything lower usually means a dent.

I don't find "huge" tires to be extremely effective. I have a lot of friends that swear by 2.5s and other large tires for all around riding. I stick to a 2.2-2.3 up front, and a 2.0-2.3 in the rear. This may sound large, but I'll do pretty crazy downhills and uphills on the same tire, and I generally don't change it. So I consider my tire size to be fairly "middle of the road" for trail riding.

I find that skills really make up the difference, and when you can get by with skinnier tires because your cornering and handling skills are better, you can go faster due to lower rolling resistance. Not a huge effect, but I've also experienced some extreme effects when looking at bit 2.7-3.0 tires compared to something smaller.

I find "traction" to be a sum of many elements. Tread compound/tread design is a pretty important element for me. Some tires, like the old Kujo and WTB Motoraptor, are just crap in their larger sizes. They have a hard compound and wash out easy. Even though they are large and may feel somewhat "sure footed" at times, they break loose easy and are hard to corner/ride agressively on. On some smaller tires like a WTB weirwolf in 2.1-2.3 or my intense 2.25, a generally softer compound and more effective tread pattern allows much better cornering and traction. This is where skills and other elements come together. A smaller tire that hooks up decently around 2.0" wide can rail around turns if the surface is niced and packed and the rider is willing to ride it in that way. That is how a smaller tire can be a lot faster.

I find that larger tires are better for stability, and some people seem to need a more "stable" ride, but smaller tires are usually faster. Which one will let you go the fastest through a turn? A big combination of skill, conditions, and tire properties determine that IMO.

Lowering tire pressure increases traction to a point, and at that point it starts to decrease as the tire seems to flatten out on the gound and slip. The achilles heel IMO is that when you decrease your pressure to try and rail turns and such faster, you are probably riding pretty agressively and lowering that tire pressure could incide damage to your rims if you ride rough terrain. I only recommend using tire pressure in the 30s for much lighter riders and women, but even then I am carefull about it. My buddy use to run 3.0s on his downhill bike with sun doublewide rims. He ran about 8 psi (yes, 8) and while he almost never flatted, his rims looked beat up as hell. This was due to running low pressure, and sometimes you may not flat, but doing damage to the rims is not fun or cool, and it's a possibility when you are running tire pressure that low. I find a lot of people that run real low pressur are generally not agressive riders that are seriously riding bikes(you're expirmenting with pressures so I'm not trying to label you into this group or anything). When they are pushed to the next level they start getting pinch flats and wonder why.

 

[SMOKEY]

Pokev,
Congrats on the new Apple, I have an ibook and I am never going back to PC. I am waiting for my "super duper hand built CUstom made for smokey who used to play games all the time" windows PC to die so I can pick up a power mac G5.
Hey ever heard of charles mingus? ? old school jazz. The best.

I hear you on the tire thing. I think it mostly depends on the terrain, but in general bigger tires seem to handle the rough with more stability and don't "squirrel" around under rocks and such. But I don't agree with some of that....more on that later....
A weird thing about my riding experience is when I first started riding I lived in Okinawa Japan. I rode a popular spider infested loop called "spider loop". I had a gary fisher hardtail with 1.95 mythos irc tires and v brakes. the trail consisted of thick jungle vegetation, NON STOP WET ROOT ACTION, mud, clay, streams, inch thick dead leaves, wet rocks, puddle after muddy puddle, occasional sand, steep ups and downs through said terrain... basically very nasty conditions. I learned to ride on tiny tires. It was doable. I did not know the difference, I had never seen a 2.5, never even knew they made 'em. Long story short, I get back to california (born and raised) and everyone has great big giant tires!

Smaller tires make you work more, you have to pick lines as opposed to just plowing through stuff. With small tires you should be light on your bike or risk flatting, denting your rim. I have been learning to finesse lately, if I could get by with smaller faster tires, why not? Big tires roll slow and heavy. I guess it depends on how and what you ride. I can ride the really rough stuff with smaller tires, just won't be able to plow through things without consequences.

 

[SMOKEY]

one more thing,
I really really doubt there are many trails that are NON STOP GNAR GNAR. I would imagine every trail has its "nasty" spots but, for the most part, most trails are going to have fire roads, smooth parts and plain old dirt. I am willing to bet that most trails consist of mostly relatively smooth trail with smaller sections of technical stuff. Why lug around huge tires and bikes just to deal with small sections of trail?

Take a look at some of peter fagerlins videos, I see guys on hardtails with normal looking tires riding some sweet stuff. If they can do it.........

 

[PoKev]

at least 40, sometimes a good bit more, most times no less. Anything in the lower 30s is risking a dent, and anything lower usually means a dent.

Thanks for the reply Jm. I've found I deflect off too many objects at anything over 36 psi. Normally run at 30 - 32 and just tried out 28 psi to see if there's much difference. I try and finesse most sections and it seems that 28 - 30 psi is my mark, at least for now. These are UST tires.

 

[PoKev]

Hey ever heard of charles mingus? ? old school jazz. The best.

Mingus is cool man.........I dig the old school 'straight ahead' stylings, Miles, Diz, Ella, Sarah Vaughn, Bird, Art Pepper, Chet Baker, Clifford Brown..........the list goes on . BTW, the iMac is the bomb.

I hear you on the tire thing. I think it mostly depends on the terrain, but in general bigger tires seem to handle the rough with more stability and don't "squirrel" around under rocks and such. Smaller tires make you work more, you have to pick lines as opposed to just plowing through stuff. With small tires you should be light on your bike or risk flatting, denting your rim. I have been learning to finesse lately, if I could get by with smaller faster tires, why not? Big tires roll slow and heavy. I guess it depends on how and what you ride. I can ride the really rough stuff with smaller tires, just won't be able to plow through things without consequences.

I've noticed this also, but since I try and finesse most technical sections the smaller UST tires with psi around 30 really hooks up and grips well. You are right though, in areas where finesse is out of the question a larger tire fits the bill. It becomes a matter of if the number of extremely rough technical stretches enough to justify running the fatter treads.

 

[The Squeaky Wheel]

Kev,
I never run PSI over 35 on larger conventional tires like the 2.35 Kendas or 2.3 Hutch and I run 28-32 with big UST tires. I ride aggressively, encounter frequent rocks and 3' drops and rarely do I ding my rims. There's just too many factors to make a blanket statement.
If your terrain calls for smaller tires & less pressure then go for it. Only personal experimentation will yield your answer (now isn't that a freestylin' jazz conclusion?)

 

[MARider]

For what it is worth...I never run my tires with more than 25PSI. My terrain cound not be more rocky and I frequently hit drops on my spot. (I weigh about 195 with gear) I have been using the same Crossmax XL wheelset for 4 years and they are still mint. I could not even imagine riding with >35PSI. Way too much deflection for me. I have a Nevegal 2.1 UST on order and am going to give it a try but otherwise have run nothing smaller than a 2.25.

 

[Bikezilla]

Another datapoint. We've got rocks galore around here. Nasty, square edge buggers all over the place. I'm 230lbs and ride 38psi UST and haven't dented a rim yet. And includes 2yrs on whimpy Vert pros and XMXLs. Even the XC rims on my HT have never been dented, and I used to pinch flat on those every other ride.

Maybe I'm lucky but considering my lack of skill and smootheness that's kind of a big leap for me to say it's just dumb luck. I don't get much high speeds, but on the way back to the lot, I do wring it out on the carriage trails, which are just big long rock gardens.

There's got to be other factors to this. Finesse and 60' lizards don't often wind up in the same sentence.

 

[gonzostrike]

That's nice, but if I run my tire pressure that low I dent my rims, which tend to be pretty expensive. That's one area where I see no benefit to UST/tubless. Lower the pressure=dent the rims, at least for me.

me too.

I think that for what Kevin is describing though, lower pressures seem pretty safe, as his trail beds sound like they're mostly soil and roots.

Kevin, I find that my tire preferences run toward thickish casings and a minimum true 2.1 size for the rear on light bikes, true 2.3 size rear on heavy bikes. I ride the northern Rockies and we have a lot of rocks, as you might imagine from the name. lightweight tires such as the Python work well only in the lower-elevation trails where we don't really have sharp or frequent rocks... and in those conditions, the Python is an amazing tire.

Schwalbe Big Jim and King Jim tires are pretty lightweight but surprisingly sturdy FEELING tires. they are sensitive to tire pressure, though.

Maxxis Minion F and R with the single ply casing are a GREAT choice if you want a bit meatier, stickier tread... but they're a square profile tire for the most part, so if you like rounder tires (IRC Kujo/Trail Bear, for example) you may not like the Minion.

The Kenda Nevegal and Blue Groove tires are good in the Stick-E single ply casing too. they're more square in profile like the Minion. The Kinetics Stick-E single ply casing is a rounder tire that might be friendlier if you like a rounder profile.

 

[PoKev]

Kev,
I never run PSI over 35 on larger conventional tires like the 2.35 Kendas or 2.3 Hutch and I run 28-32 with big UST tires. I ride aggressively, encounter frequent rocks and 3' drops and rarely do I ding my rims. There's just too many factors to make a blanket statement.
If your terrain calls for smaller tires & less pressure then go for it. Only personal experimentation will yield your answer (now isn't that a freestylin' jazz conclusion?)

Tis the wise 'grasshopper' who finds his way is not necessarily the way of others.
Experimentation..............well Squeak that's exactly why I have 2 sets of Crossmax Enduros, to run different sets of tires. I just keep coming back to the 2.0 - 2.1s. I do BTW like the Enduro 2.4 2Bliss as a front tire. That rascal eats up everything. I know tire size and psi are personal preferences, was just wondering what others thought on the subject.

Twizzle, twazzle. twazzle. twum............time for this one to continue on that freeform journey.

 

[Jm.]

me too.

I think that for what Kevin is describing though, lower pressures seem pretty safe, as his trail beds sound like they're mostly soil and roots.

The other thing is that while I've found ~2.2-2.3 to be a great tire size for me, I keep ripping up these "lightweight" 2.2-2.3 tires too easy. Just literally tearing the casing apart on rocky trails in phoenix, sedona, and other places. Seems like they make them with thinner sidewals than 2.0 tires to keep the weight down, but they end up being pretty fragile.

 

[miles e]

Large tires, smaller tires.................is it the tire size or the pressure? I'm running UST so I can go into the upper 20's with no adverse effects (I weigh ~185). Whaddya think???????????

I think a lot of it does come down to pressure- generally a wider (higher volume) tire will allow you to run lower pressure with less risk of pinch flatting/bottoming out the rim. However, if you're successfully running 28 psi on a 2.0" tire then you have one less reason to opt for a larger tire.

The other thing is that a wider tire effectively smooths out the trail (or requires less finesse, depending on your perspective), much like 5" of travel. This is why the conventional wisdom is that when you need more travel you need wider tires too, but maybe your trails/riding style are better served by the additional travel but not the larger tires.

I run 2.5" Kenda Stick-E rubbers on my Spot for the simple reason that I am spoiled by the traction my 29"er offers on loose climbs, and these tires are as close as I can find to replicating that grip on a 26" wheel. There are plenty of other techy parts of the trail where the 2.5's are nice, but overall I'd probably run something around 2.3" if my primary goal was other than to maximize climbing in loose conditions.

 

[PoKev]

The other thing is that while I've found ~2.2-2.3 to be a great tire size for me, I keep ripping up these "lightweight" 2.2-2.3 tires too easy. Just literally tearing the casing apart on rocky trails in phoenix, sedona, and other places. Seems like they make them with thinner sidewals than 2.0 tires to keep the weight down, but they end up being pretty fragile.

I agree, with the lightweight UST tires I've had a couple of cut and puncture problems that were eliminated when I returned the the regular UST model. So, I've given up looking for a super light UST tire. Generally I've found that if it climbs a loose section well then it seems to maintain tracction in most other areas.

Kevin

 

[gonzostrike]

The other thing is that while I've found ~2.2-2.3 to be a great tire size for me, I keep ripping up these "lightweight" 2.2-2.3 tires too easy. Just literally tearing the casing apart on rocky trails in phoenix, sedona, and other places. Seems like they make them with thinner sidewals than 2.0 tires to keep the weight down, but they end up being pretty fragile.

exactly. when I run those extra light casing tires in the granite/shale rocks, they last about 1-2 rides before getting pinch flatted (commonest) or sidewall tear (fairly common too).

the Kenda Stick-E single ply casings are a good bit burlier than, say, a Hutchinson "Airlight", a Schwalbe "Light", a WTB "Race", a Continental **any non-DH** casing.

the old school Tioga DH Pro, which I still run on a few bikes, is a great compromise tire that doesn't go way above 1000gms for a sturdy sidewall at 2.3" width. you have to like the tread pattern, though.

 

[Jm.]

the old school Tioga DH Pro, which I still run on a few bikes, is a great compromise tire that doesn't go way above 1000gms for a sturdy sidewall at 2.3" width. you have to like the tread pattern, though.

I know, works good on certain surfaces, like slightly damp hardpacked trail, you can rail on those tires.

 

[tscheezy]

I ran the Tioga DH Pro 2.3s (big 2.3s) on my last Utah trip. Not a single flat (I kept them at 40psi in back, 35 in front). They hook up great, have burly side walls, and actually wore fairly well considering they are a bit softer compound and I ran them on sandstone the whole time. Pricepoint had them for like $20 for ther pair, I think. A great Moab tire. Cheap, big, stout, grippy.

 

[slowrider]

Tire size

I think tread patern is more important than tire size for grip but with all else being equal I like larger tires. I tried the conti Vert pro in 2.1 and 2.3 and the 2.0 and 2.2 Specialized enduro's and I felt the larger tires gripped better.