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  1. #1
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    Wider Rims and Lower Pressures

    Given the recent trend of using as wide a rim as possible (for a given tire size) for purposes of maximizing tire spread and allowing much lower pressures to increase traction I have questions. Isn't the minimum tire pressure one can use limited by the weight of the rider? As a heavier rider with gear, I don't usually run much less than 30 psi in tubeless tires and can't imagine running pressures under 20 psi that other riders are reporting. Can someone help me better understand if going this route would be an advantage at all? Thanks for comments, opinions and experience.

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    Tire pressures and rim choice is one of the most discussed topics. I'm not sure I could add much other than my exceriences.

    Wider wheels only make a small but incremental change in contact patch. They also increase overall air volume by an incremental amount. They can also aid in preventing tire roll and squirm because the tire isnt wrapped into as much of a circle when on the bead of the rim. For me this is all a benefit to a point.

    I run the lowest pressure that avoids rim hits and excessive tire squirm. Squirm is subjective. For me that is 14 psi on 3inch 29+ on 50mm scrapers, 11 psi on 4.6inch fatties on 90mm carbon, and 22 psi on 26x2.4 on 25mm rims. Like everyone else I go really low on snow with the fat tires. As one more point my kid runs 12 in his alomst 3inch 27+.

    Ive tried 100 different pressures and combinations. For traction, compliance, fun, and overall amature speed this is the best for me. I've never lost a rim to a hit unless I went flat, which has little to do with the starting psi. I'm 180# in riging gear, and ride 28 to 30# bikes.

    I would experiment and see where you end up. Let out 2 psi at a time an see if things are better or worse. Carry a pump for a few rides to save co2. If it isn't for you, more air is free.

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    I guess I'm just lucky. I'm a fat guy and I run low pressures without much issue, both tubed and tubeless. I've pinch flatted and dented a rim once.

    I run 10-12 psi in my 29x3.00 on 30mm internal rims. (WTB Freq i35 or Velocity P35)
    I run 15-18 psi in my 29x2.35 on 30mm internal rims. (WTB Freq i35 or Velocity P35)
    I run 18-25 psi in my 29x2.35 on WTB KOM i23 rims.
    I run 11-15 psi in my 27.5x2.8 on WTB i45 Scrapers.
    I run 2-8 psi in my 26x4.7 on 80mm Mulefut rims.

    Even on the road I run "low" pressures.
    I run 60-65 psi in my 700c x 35 on H Plus Son Formation Face (20mm external)
    I run 85-90 psi in my 700c x 25 on H Plus Son Archetypes (23mm external)

    I weigh 230-250 depending on the season. I ride mainly XC, am kind of slow, but I smash over stuff.

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    I weigh 215lb. and find running lower than 30psi causes rim strikes. I pinched the sidewall on a set of carbon 30mm ID rims trying to run less than 30psi. My first tubeless conversion I set my psi less than tubed after seasons of use my pressures are about the same as tubed.

  5. #5
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    Quote Originally Posted by keen View Post
    I weigh 215lb. and find running lower than 30psi causes rim strikes.
    This is where I'm at, as well, on 'normal' rims.

    Width does make a difference in pressure.

    I only run 2.4 tires, generally. With my 29er, on 26mm internal rims, I ended up bumping up to 35psi rear, from 30, due to excessive pinch flats.

    Same size tires on my 26"x47mm rims, I can run 25psi, and have only managed one pinch, when I bottomed it on a razor sharp chunk of shale. Those rims are 40mm internal IIRC.

    Big difference, based on a 14mm increase in rim width. Both are hardtails.

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    Wider rims may or may not allow lower pressures. It depends on what's limiting your minimum pressure. If it's due to squirm or burping, wider rims may allow you to run less pressure. If you're hitting the rims, you probably won't be able to go lower regardless of rim width.

  7. #7
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    With wider rims and the same tire, you have to run lower pressures to get the same softness and compliance out of the tire. It'll run firmer with less roll even at lower pressures.

    This isn't necessarily a benefit. It means you may have to drop pressure so low that you get rim strikes to get it feeling right. Or pump it up high enough to not hit the rim and deal with the harshness.

    These big rims really need big tires. There's some big downsides that tons of riders are finding when using small tires.

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    I'm 240 Lbs, and have no trouble running a 2.25 ardent tubeless at 23 psi on a 23mm ID rim. Ive also found the plus bike sweet spot for me is a 2.8 NN at 15/16 psi on a 45mm ID rim. Wider and higher volume really does allow you to run lower pressures. At first it feels like youre riding on a flat tire, but once you get used to it, the rolling resistance is only a couple of watts or power, but the traction increase is substantial.

  9. #9
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    Quote Originally Posted by TheHamster View Post
    Given the recent trend of using as wide a rim as possible (for a given tire size) for purposes of maximizing tire spread and allowing much lower pressures to increase traction I have questions. Isn't the minimum tire pressure one can use limited by the weight of the rider? As a heavier rider with gear, I don't usually run much less than 30 psi in tubeless tires and can't imagine running pressures under 20 psi that other riders are reporting. Can someone help me better understand if going this route would be an advantage at all? Thanks for comments, opinions and experience.
    Don't be fooled. People running 20psi are either riding very tame trails, very tame riders, or using 3.0 and bigger tires.

    Unfortunately, people have started lowering their pressure more, to cover 98% of their riding, rather than keeping it where they don't have to worry about an impact. When that 2% does rear it's head, the results are more catastrophic with the low pressure being run. We ran wide rims back in the day DHing, this is nothing new. We even used big tires. The reason we used the pressure we did wasn't because a pinch flat would happen, it was because we could hit the rim on rocks. That might have also caused a pinch flat, but hitting rocks with a rim is usually going to trash it, which we did. So many of us know how low we can go, and it's nowhere as ridiculously low as some people are using.

    You only use as low as you are willing to risk for rim strikes.

    When I DH, I use a 2.5 to 2.3" tire, running 35mm rims. I need around 38 in the rear to not kill the rim on rocks, closer to 34-35 on the front for the same. If the terrain is more tame I can lower a few PSI, but not a lot. Not lower than 30, then I risk striking the rim again.
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    There doesnt seem to be a correlation between tire pressure and weight. It really depends if you ride light or heavy and how much of your weight you put behind it. The tire that you use also makes a big difference. I can go lower in pressure if i use a tire with a thicker casing versus a thin walled xc tire. The only way is to experiment and see how low you can go without hitting your rim or blowing it off.

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  11. #11
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    Quote Originally Posted by Jayem View Post
    Don't be fooled. People running 20psi are either riding very tame trails, very tame riders, or using 3.0 and bigger tires.

    Unfortunately, people have started lowering their pressure more, to cover 98% of their riding, rather than keeping it where they don't have to worry about an impact. When that 2% does rear it's head, the results are more catastrophic with the low pressure being run. We ran wide rims back in the day DHing, this is nothing new. We even used big tires. The reason we used the pressure we did wasn't because a pinch flat would happen, it was because we could hit the rim on rocks. That might have also caused a pinch flat, but hitting rocks with a rim is usually going to trash it, which we did. So many of us know how low we can go, and it's nowhere as ridiculously low as some people are using.

    You only use as low as you are willing to risk for rim strikes.

    When I DH, I use a 2.5 to 2.3" tire, running 35mm rims. I need around 38 in the rear to not kill the rim on rocks, closer to 34-35 on the front for the same. If the terrain is more tame I can lower a few PSI, but not a lot. Not lower than 30, then I risk striking the rim again.
    Agree....however rim diameter also effects the psi.

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    All the replies to this thread have been excellent, i think.

    Quote Originally Posted by TheHamster View Post
    Given the recent trend of using as wide a rim as possible (for a given tire size) for purposes of maximizing tire spread and allowing much lower pressures to increase traction I have questions. Isn't the minimum tire pressure one can use limited by the weight of the rider? As a heavier rider with gear, I don't usually run much less than 30 psi in tubeless tires and can't imagine running pressures under 20 psi that other riders are reporting. Can someone help me better understand if going this route would be an advantage at all? Thanks for comments, opinions and experience.
    I'm 215lbs and an 'expert' rider, but among properly good riders i'm completely unremarkable. My experience matches yours; 20 psi is out of the question regardless of tire/rim size. I can run lower pressures with high volume tires and similarly wide rims, but that means going from mid 30s to mid 20s, which is still a lot. I don't care for them; i don't like how it can't drift through corners and big impacts (landing to flat, for example) aren't what i'm familiar with. I'm not in love with the high volume tire options currently available, and i'm not sure the casings, tread designs i've liked the best would translate to extra-high-volume versions.

    I've only experimented with + tires on demo bikes, so no real investment, but i don't think they're for me. They have their appeal, for sure; they swallow trail chatter amazingly and braking traction is fantastic.

    Narrow rims and big tires is crap though.
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  13. #13
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    Pressure is all relative to your weight OP, you can run lower with wider rims, but don't go trying to run what a lighter rider can run, just won't work, but depending on what brand and casing you run, you might be amazed at what soprt of pressures you can use.

    I'd say you have a not very good gauge, that's what I'd say. I barely weigh about 185lbs geared to ride and I run WTB i29 rims, 2.3" EXO Maxxis tyres and I don't even run what you're claiming in my front, 17-18 PSI is the absolute lowest I go and that's for slower trails without speed and rocks to land into. Suggest you get an accurate low pressure gauge or you really don't have an idea of what "Bash into" means and/or you're running full on DH casing tyres. I use a Topeak Digital Smart gauge.

    Quote Originally Posted by slowride454 View Post
    I guess I'm just lucky. I'm a fat guy and I run low pressures without much issue, both tubed and tubeless. I've pinch flatted and dented a rim once.

    I run 10-12 psi in my 29x3.00 on 30mm internal rims. (WTB Freq i35 or Velocity P35)
    I run 15-18 psi in my 29x2.35 on 30mm internal rims. (WTB Freq i35 or Velocity P35)
    I run 18-25 psi in my 29x2.35 on WTB KOM i23 rims.
    I run 11-15 psi in my 27.5x2.8 on WTB i45 Scrapers.
    I run 2-8 psi in my 26x4.7 on 80mm Mulefut rims.

    Even on the road I run "low" pressures.
    I run 60-65 psi in my 700c x 35 on H Plus Son Formation Face (20mm external)
    I run 85-90 psi in my 700c x 25 on H Plus Son Archetypes (23mm external)

    I weigh 230-250 depending on the season. I ride mainly XC, am kind of slow, but I smash over stuff.
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    I use a SKS digital gauge. I live in Wisconsin, so all my riding is tame XC. I am not fast, my race times are about 2 minutes per mile slower than the fast guys. My description of smashing over stuff is when I come to rocks and roots I just get out of the saddle, I don't try to bunny hop over stuff or try to pick my way through because I'm usually tired out and would mess it up. I just lean back and let the bike to the work. For people who are lucky enough to live places where you can actually "mountain" bike then I'm sure higher pressures and tougher tires are warranted. It does sometimes suck that the way I ride and the way Aaron Gwin rides are all lumped under "mountain biking".

    Also consider, tire pressure reading are taken with the bike unloaded. A fatter rider will cause a higher pressure rise as the tire deforms more under them. Notice that some of the guys who ride fatbikes in super soft powder will sometimes set up their tires with negative pressures so when they get on the pressure goes slightly positive.

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    I'm glad that we're no longer in the days of 16-17mm wide rims and 1.9" tires, but that doesn't mean I like 40mm rims and 3" tires any better.

    In my experience, for the riding I do, the claimed benefits of wider rims are marginal at best and far outweighed by the disadvantages. I weigh 150lbs and every time I go below 28psi on a 2.3" tire I either rip the tire off the rim and/or smash the crap out of the rim. I've done this to every rim from 19-35mm wide which is why I keep my tire pressure in the 30-32psi range. I'd like to go lower for more comfort & grip but I don't have the time & money to replace rims & tires every few weeks.

    The downside for me is weight and lack of good tires. A wide rim is going to be heavier and I'm not willing to deal with 550-600g rims on anything that isn't a dedicated DH bike. Yes I could go carbon, but a regular width carbon rim would still be significantly lighter than a wide one. As for tires, about the only decent tires for wide rims are the DHF/DHR2 WT, pretty much everything else sucks. Even the Maxxis combo doesn't perform as well as the Michelin Wild Rock'r2 on a 25mm rim, and putting the Michelins on a wide rim screws up their performance.

    If didn't ride my enduro bike at DH speeds on a frequent basis and spent most of my time at low to moderate speeds where random rim smashes and exploded tires aren't a concern, then I might see things differently. The rim weight would still bug me but at least I'd have a half decent selection of tires for my needs.

  16. #16
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    I am 215 and on my rigid SS 22-24 psi is the sweet spot. For my 130mm trail bike 25-27.

    Both 29'ers.

    My son is 145 lbs and runs his 29'er at 20psi and 27.5 enduro at 25psi

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    I run a 26" 2.3 up front and a 2.2 in back, both specialized brand tires. Purgatory and captain (tubeless) on stans flow rims. I weigh around 195 geared up and run my pressures around 12psi. I usually run 18/20psi but on my last ride I noticed my tires were a little soft before I left the house. I'll just inflate at the trail head I said to myself. Well that thought went out the door. I've ridden this particular trail numerous times, but this ride felt different, much different. I felt like the bike was floating over everything. Checked the pressures when I got home, 10.5 in front and 11.5 in back. I do recall banging the rim once, I just added another lb or 2 and all seems good. I'm not running DH speeds but do like to motor along. Finding the right pressure for your riding style and terrain takes a bit of experimenting. I'm close to finding mine.
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    Agree...^^^

    For me...in an effort to keep things simple. I try to run PSI that is just slightly above where the tire starts to squirm. This number will change with tires due to variances in their sidewalls. Rim width changes. Speed of riding (slow twisty singletrack, fast flowy with minimal jumps, fast rocky, etc) It really depends on so many factors that one needs to find their sweet spot for their riding, tire and rim selection. I think it is good to have some general guidelines provided from some rim manufactures but also need to be tweaked for your riding pleasures. :-)

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    Just smashed up a Derby HD layup carbon rim running about 26psi in the back. Depends on your terrain. Rim is 29x35mm and I was running a Highroller II 29x2.3. I was riding desert chunk and this obviously wasn't enough.
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  20. #20
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    Tire pressure is limited by rider weight AND terrain conditions AND speed. Add in the tire profile- rounded or square to pick the right tire for the width of your rim. Or the best rim width for a tire.
    So setups are go or no go based on all those factors.
    One guy can hate Plus and another finds it the best thing out there.

  21. #21
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    This is all really great information. My conclusion is that depending on conditions may not need (or be able to use) the widest rim with the lowest pressure. I am at least 200 lbs with full gear and ready to ride. None of the trails I ride are smooth--tons of rocks and roots with very little smooth hardpack. All of the tires I run (16, 27.5 and 29) range from 2.25 to 2.4. So from what I have heard here will need to experiment with my wheel tire to see how far I can go without hitting my rims on rocks. I probably won't lose sleep over not owning i29 rims and just messing around with my i23s and i25s my be all I need to do.

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    I have three sets of wheels, 29x35mm, 29x25mm and 27.5x35mm (all internal width). I am 220 and ride a mix of things, but do fast flowy and bermy trails. On those, I need a minimum 22psi for the B+ wheels and 30psi for the 29ers. I would be hard pressed to see anyone my weight go under 20psi with the B+ wheels at high speed, it would be a near death experience. There certainly are less aggressive trails where I could lower the pressure and it would feel like I was relaxing on my couch. I was shocked to learn this as I saw all these people talking about running same B+ config at 15-16psi, not possible with my weight and trails. Same thing with the 29ers, hi speed and steep banked turns create far too much lateral force at my weight and will fold the tire if I don't stay up above 30psi. But I do find that the a 29x2.5 on the 35mm rim is a crazy good climbing tire at 25 psi, so I have sometimes ridden up low psi and then inflated at the top. I think most people do the opposite... YMMV.

  23. #23
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    Good thread Hamster! I had the same question when I went from i-23's to Nox Farlows (29mm ID). I found I could only lower about 2 psi per tire based on the extra rim width (28r/25f to 26r/23fr, 185# w/gear). Any lower and I would get the "squirm of death". So on a "what pressure you runnin" thread on the Nox forum almost everyone was in the teens and I was like WTF?! Came to the same conclusion Jayem stated - slower riders on tame trails that don't carve turns cause there's no way you can get away with that at speed!

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    Squirm is one thing, but IMO if you are even close to squirm in the summer, you are ripe for a rim strike. In the winter, we run just enough pressure that we aren't squirming, it takes more pressure when the conditions are harder, less when it's new snow, but there's little worry about rim strikes in these conditions. Anywhere near squirm for me in the summer is enough that I can dent the rim riding into curb easily.
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    Ah, now that makes sense once you describe it FYI, you're not bashing, you're just popping and hoping off/over every little thing, but you most definitely are not bashing if you're aware and un-weighting and lifting your front end about/over stuff, you're just riding how you should Bashing to me is just plowing a straight line through/over whatever without any sort of finesse or un-weighting of your bike, like I can do with my 130/140mm bike if I want.

    Quote Originally Posted by slowride454 View Post
    I use a SKS digital gauge. I live in Wisconsin, so all my riding is tame XC. I am not fast, my race times are about 2 minutes per mile slower than the fast guys. My description of smashing over stuff is when I come to rocks and roots I just get out of the saddle, I don't try to bunny hop over stuff or try to pick my way through because I'm usually tired out and would mess it up. I just lean back and let the bike to the work. For people who are lucky enough to live places where you can actually "mountain" bike then I'm sure higher pressures and tougher tires are warranted.
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  26. #26
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    Quote Originally Posted by Jayem View Post
    Don't be fooled. People running 20psi are either riding very tame trails, very tame riders, or using 3.0 and bigger tires.
    Some pros on the EWS circuit are running pressures in the low 20s- Justin Leov for example says he ran ~20psi at Rotorua.

    Too low for me!

    My experience: get a good digital gauge, figure out what works for you & your set up, and check it every ride. Every rider/rim/tire/trail combo has a different sweet spot & a good gauge makes it so much easier to tune in.

  27. #27
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    Quote Originally Posted by Jayem View Post
    Don't be fooled. People running 20psi are either riding very tame trails, very tame riders, or using 3.0 and bigger tires.
    I don't feel like thats a universal truth. For bigger riders doing lift-service stuff, sure. I weigh 160 trail ready, those pressures have never been a problem for me.
    I want to say I've seen pics of you riding in AZ (SoMo, White Tanks), and commenting in the AZ regional forum. So you know the type of terrain here. Again at 160 lbs, I was running 23-25psi on a 21mm inner rim and never had a problem everything anywhere in AZ, including the 'bigger' stuff in Flagstaff, Sedona and all the infamous chunk around the valley, riding a 140mm FS bike.

    With 31mm inner rims on a short travel single speed I set my pressures at 20F/22R on 2.25 tires (measured 2.32 mounted) and was actually thinking of dropping 2 more psi last night riding Dreamy Draw. I really feel like I could get away with high teens with no rim strikes unless I got careless with line choice. I'm certain I could ease the pressure down a bit mounting a big 2.4.

    Im not a super hard-charger, but I don't feel like "very tame" applies to either me or trail. I imagine the average MTBR'er at my weight would say similarly.

  28. #28
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    30id carbon rims here.
    Front 2.35 schwalbe magic mary vertstar, gravity sidewalls - 15psi
    Rear Nobby Nic 2.35 pacestar snake skin 18psi.
    140lbs rider ready to ride.
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  29. #29
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    Something to keep in mind that some of the "roadie" tire gauges with a 100+psi scale that a lot of us are using are not real accurate at lower pressures. So there may be some variation in the reading vs. actual pressure.

    Here is my experience with Hans Dampf 2.35s on 3 different internal width rims:

    17mm internal: Tire very floppy, and higher pressures were required to keep it stable.

    25.5mm internal: Huge improvement. Could lower pressure down until rim strikes became an issue. At those pressures, there was some squirm at high Gs.

    35mm internal: Very small improvement. Squirm was gone, but going lower led to rim strikes. Side note: Sidewalls of the tire were worn away in a short time by rocks, even though tread was still good. The sidewalls stuck out further than the widest part of the knob. Also rims got scraped up quite a bit, but just cosmetically.

    I get a fair amount of rim strikes because I feel the lower pressures are worth it, and I run rims and tires that can take it. I get riding light and of course do it, but when you are really pushing it, stuff happens. I'm heavy and to preserve momentum, I'll stay off the brakes even if I know the rims might take a beating.

    Procore solved all of this and was awesome performance-wise. But I had some problems with it and decided to go back to a simple tire and rim setup.

    I'd like to see bike tire manufacturers provide a recommended rim width range for each tire like the car tire manufacturers do.

  30. #30
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    I like to ride my rigid SS with 18 psi.

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    These numbers don't make any sense to me at all! I think that riding style and terrain play a bigger part than weight. I'm about 180# just hanging around. I'm not sure how accurate my gauge is, but it's rarely under 30. Many local trails around here (okanagan, B.C., Canada) are very rocky. I would say I'm a pretty alright rider, but rather aggressive, and I my back rim is beat to hell. Tubeless is the only way I can get down without stopping haha. And if I go to the bike park (Silver Star Mtn) I put tubes in, otherwise I just peel the tire off on a couple of the flowier trails. I'm running a High roller2 on a 29" Easton ARC30 out back. Works ok, but next time will be something with DH casing. I ride everything for fun, but the downs are the most fun. All this might have something to do with my bmx background though, and being much more back wheel oriented...

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    Does anyone know the pros and cons of using a 34mm ID rim with 2.2 tires for xc racing ?

    What I really want is something like a race king in 2.5-2.6 but they dontt make those. I want this to be able to lower tire pressure for a more compliant ride without getting hit with the extra RR penalty due to the small knobs.

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    Quote Originally Posted by ARandomBiker View Post
    I don't feel like thats a universal truth. For bigger riders doing lift-service stuff, sure. I weigh 160 trail ready, those pressures have never been a problem for me.
    I want to say I've seen pics of you riding in AZ (SoMo, White Tanks), and commenting in the AZ regional forum. So you know the type of terrain here. Again at 160 lbs, I was running 23-25psi on a 21mm inner rim and never had a problem everything anywhere in AZ, including the 'bigger' stuff in Flagstaff, Sedona and all the infamous chunk around the valley, riding a 140mm FS bike.

    With 31mm inner rims on a short travel single speed I set my pressures at 20F/22R on 2.25 tires (measured 2.32 mounted) and was actually thinking of dropping 2 more psi last night riding Dreamy Draw. I really feel like I could get away with high teens with no rim strikes unless I got careless with line choice. I'm certain I could ease the pressure down a bit mounting a big 2.4.

    Im not a super hard-charger, but I don't feel like "very tame" applies to either me or trail. I imagine the average MTBR'er at my weight would say similarly.
    I have 2.35 RRs mounted to 34 mm IDs and regularly run 16-18 psi. I weigh 230 and ride xc. There's an extreme amount of confidence there with no squirm. Lighter people could prolly get away with 12-15 psi on this setup.

  34. #34
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    Quote Originally Posted by philreske8614 View Post
    Does anyone know the pros and cons of using a 34mm ID rim with 2.2 tires for xc racing ?

    What I really want is something like a race king in 2.5-2.6 but they dontt make those. I want this to be able to lower tire pressure for a more compliant ride without getting hit with the extra RR penalty due to the small knobs.
    I find that significantly heavier wheels get sluggish pretty fast in the turns and climbing. If you aren't very aggressive/fit, you might not notice much of a difference, but I do when racing, whether DH or XC. A few hundred extra grams of tire and rim are very noticeable to me, I can't cut turns at speed quite as sharp and they take a bit more energy. That seems real wide for XC racing to me, which means it's probably carrying a bit of extra weight, going to an even wider tire would put more weight further away from the center, which again, I tend to notice, especially if it's on a 29er wheel.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  35. #35
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    Wider Rims and Lower Pressures

    Quote Originally Posted by Jayem View Post
    I find that significantly heavier wheels get sluggish pretty fast in the turns and climbing. If you aren't very aggressive/fit, you might not notice much of a difference, but I do when racing, whether DH or XC. A few hundred extra grams of tire and rim are very noticeable to me, I can't cut turns at speed quite as sharp and they take a bit more energy. That seems real wide for XC racing to me, which means it's probably carrying a bit of extra weight, going to an even wider tire would put more weight further away from the center, which again, I tend to notice, especially if it's on a 29er wheel.
    I notice this too but can never determine whether or not it is due to increased traction in terms of rr or weight. I appreciate the feedback.

    I also have an I9 torch set that has 23 Id and is lighter overall although not carbon. What is the ideal wheelset weight nowadays ?
    Like 1600g?

  36. #36
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    Quote Originally Posted by philreske8614 View Post
    What is the ideal wheelset weight nowadays ?
    Like 1600g?
    As light as possible while still staying in one piece for as long as you want it to.

    If your current rims are staying straight & undamaged for at least a season of use you can go lighter, rinse & repeat until the rims start getting trashed unacceptably fast, then back it off a notch. How light you can go depends greatly on the rider and how the bike is used, on my XC bike I can run weight weenie wheels since it's not getting jumped or slammed into things at high speed. On my enduro bike I need much heavier & stronger rims since I abuse the hell out of that bike and it gets ridden at speeds that most people won't see on their DH bikes.

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