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  1. #1
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    Adjust your tires PSI on the fly?

    Just read about this. The basic idea sounds wonderful, lower air pressure when you need the grip, increase it for easier peddling when you don't. In practical terms, who knows if this will really make sense, but neat idea all the same.

    ADAPTRAC changes mountain bikes' tire pressure on the fly

  2. #2
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    I think for the added weight of the system ill deal with static tire pressures.
    2010 Giant Yukon FX
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  3. #3
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    That swivel connection on the side will last about 13 nanoseconds before it is ripped off with a resounding "woosh" and then you be walkin.

  4. #4
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    You should re- post this in the fatbike section...

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    Interesting, but I think I'll pass, too. Seems like more things to fail. I've managed to find my happy place on tire pressure. Novel though. Thanks for sharing. Someone will buy it.

    PS Interesting website gizmag

  6. #6
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    Quote Originally Posted by Smilely View Post
    Just read about this. The basic idea sounds wonderful, lower air pressure when you need the grip, increase it for easier peddling when you don't. In practical terms, who knows if this will really make sense, but neat idea all the same.

    ADAPTRAC changes mountain bikes' tire pressure on the fly
    Huh, I never really saw the point of running my mtb tires any higher than the lowest I can get away with. When would I want them pumped higher? For long sections of pavement?
    15mm is a second-best solution to a problem that was already solved.

  7. #7
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    Really cool. I have thought about a system like this for a while. Its neat someone finally created a prototype.

    I dont necessarily think it will take off but the innovation is awesome to see.
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    LOL!

    The first thing I did after I finished reading the article, was to check the publishing date.

    I sure did expect it to be April 1st.


    Magura

  9. #9
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    I am still fairly new, been riding reguarly for just over a year, but I do notice that when I have the air pressure lower, to get better grip on roots and such, it takes more effort to pedal, particuarly on climbs. Perhaps my "engine" just is not strong enough :-)
    Anyway, Gizmag is a site I enjoy reading and when I saw this thought it should be shared here. Neat idea, doubtful the cost, weight penalty and extra complications that would come with it would make it worth it though.

  10. #10
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    Quote Originally Posted by Sheepo5669 View Post
    Really cool. I have thought about a system like this for a while. Its neat someone finally created a prototype.

    I dont necessarily think it will take off but the innovation is awesome to see.
    My thoughts exactly.

  11. #11
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    It's kind of cool, but my bike is complicated enough already. I don't even change my tire pressure for different riding spots, I really don't want to mess with it mid-ride.

    I'd be afraid of damaging something. Maybe not the thing on the side, but the hose that runs out parallel to the spokes.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  12. #12
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    I doubt I would use it as well. I can't remember the last time I even bothered to lock-out my fork so I don't know that I'd bother worrying about my PSI on the fly.
    Quote Originally Posted by Ilikebmx999 View Post
    Are we just ignoring balls? Lol

  13. #13
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    I have on occasion pumped up the tires for a road ride to the trails then bled down for the trail....

    Then pumped up for the ride back home....

    I just used my pump...the total milage for the day was just over 163 km a century...

    I didn't mind the small break.

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    Quote Originally Posted by AZ.MTNS View Post
    That swivel connection on the side will last about 13 nanoseconds before it is ripped off with a resounding "woosh" and then you be walkin.
    Yup. Its just a one-touch fitting, so I would hope they would develope it to better integrate with the hub on the real version. I still don't think the tire pressure is what I would worry about on a ride, not like I am in a race each and every day that I ride.
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  15. #15
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    I think I'd want that thing even less on a race day. Brakes and shifters are enough, thank you, and part of why I like hydraulics is that they never need adjustment mid-ride. One of these days, I'm going to have to try singlespeed.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  16. #16
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    Quote Originally Posted by zeppy View Post
    I can't remember the last time I even bothered to lock-out my fork so I don't know that I'd bother worrying about my PSI on the fly.
    +1
    lowered my seat for the first time last weekend (only for a steep downhill), wont bother doing it again because I couldn't be fukt, air pressures.....pffft
    always mad and usually drunk......

  17. #17
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    No thanks. This is another solution to a problem that does not exist.

  18. #18
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    I think its been pretty well proven that lower pressure equals lower resistance.

  19. #19
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    Quote Originally Posted by One Pivot View Post
    I think its been pretty well proven that lower pressure equals lower resistance.
    Thanks for that, Mr. Non Sequitur!

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    Its pretty linear with the thread.. the whole premise of the device is that its somehow helping you by pushing up your pressure. This isnt true. Theres enough tests out there now to prove it from more than a few sources. Its just entirely a bad idea.

  21. #21
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    Quote Originally Posted by kapusta View Post
    Huh, I never really saw the point of running my mtb tires any higher than the lowest I can get away with. When would I want them pumped higher? For long sections of pavement?
    If you do need to ride a long distance to get to the trail then higher PSI is better. Most people don't need to do this though.

  22. #22
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    Quote Originally Posted by Rabies010 View Post
    You should re- post this in the fatbike section...
    A buddy of mine with a Pugsley asked me about this years ago ("like a Hummer", he said). Fat bike tire pressure is a little more of an issue esp. if you are on mixed terrain like hard to sand, or frozen to snow. The benefits of pressure changes are instantly realized.

    I'm sure these guys will integrate the system a lot better and someday the seat post or the handlebar or something will double as the compressed air canister. Heck, they could build a shock absorbing seat post that pressurizes a reservoir while you bounce down the trail.

    I'd like to see if the system doesn't leak, though. Rotating air seals are a tricky business. The stock fittings on the outside are pretty reliable, but I wonder more about the internals of the hub.

    Very cool idea!

    -F
    Last edited by Fleas; 04-19-2012 at 07:31 AM.
    It's never easier - you just go faster.

  23. #23
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    I want to see this contraption on a bike that also has a dropper seatpost and remote lockouts for both front and rear suspension. All those cables, lines, and levers... What a mess!

    While interesting, it will find itself in the scrap heap with 2WD. Too complicated for the minor benefit involved.

  24. #24
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    Quote Originally Posted by Fleas View Post
    Heck, they could build a shock absorbing seat post that pressurizes a reservoir while you bounce down the trail.-F


    You have no idea how much money I would pay to watch someone try to bounce on their seat to try and air up their tires. The mental image alone is comic gold.
    2010 Giant Yukon FX
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  25. #25
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    Quote Originally Posted by SuperSlow35th View Post
    You have no idea how much money I would pay to watch someone try to bounce on their seat to try and air up their tires. The mental image alone is comic gold.
    Ha ha! That is a funny visual, but we are seeing it differently.

    The cheapo pogo seat posts have about 1" of travel. With a 1" stroke air pump, it would probably take more than a few miles of bumpy riding to pump up a reservoir with enough air for a fat bike. But once it's filled, you would only use a little air at a time in adjusting your tire pressure, and the reservoir would always be topped off with no extra work from the rider. If you charged it with a pump before you installed it it would always be ready - on-board air tank, just like the off-road trucks.

    -F
    It's never easier - you just go faster.

  26. #26
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    Ah ok I see what your getting at. I was thinking of the seatpost as a conventional air pump handle. And I about spit coke across my keyboard at the mental image.
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  27. #27
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    Nice idea

  28. #28
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    I like

  29. #29
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    The idea about pumping it using a suspension seatpost, is not all that bad.

    The only issues I can see in that solution, would be that it would add even more weight, and that I guess most of us would not like to have a suspension seatpost in the first place.

    Co2 cartridges seems like a good solution, just a heavy one.

    Magura

  30. #30
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    It just dawned on me, that a bladder in the seat, may work out, and would be a fairly light solution.

    That way it could pump a cartridge during the ride, and keep it topped up.

    Not that I would like one myself, but it could make for a workable solution.


    Magura

  31. #31
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    Quote Originally Posted by Thor29 View Post
    I want to see this contraption on a bike that also has a dropper seatpost and remote lockouts for both front and rear suspension. All those cables, lines, and levers... What a mess!

    While interesting, it will find itself in the scrap heap with 2WD. Too complicated for the minor benefit involved.
    With all those remotes fitted you'd have so many levers on the handlebars it would be difficult to know which one to press. You'd need to take the manuals with you also.

    Pictured below: Adaptrac remote and gauges
    Control Valve and Gauges | Adaptrac

    2013 Fox DOSS and shock remote levers
    FOX 2013: New CTD Damper, 34 Forks And More - BikeRadar
    Attached Thumbnails Attached Thumbnails Adjust your tires PSI on the fly?-adaptrac_gauge.jpg  

    Adjust your tires PSI on the fly?-fox_doss_lever.jpg  


  32. #32
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    I think there's an easier solution. You don't really want higher air pressure, you want less tire deformation for smooth sections. higher air pressure does lead to less deformation, but its not the only way.

    A tube with multiple walls along radial cross-sections that you could open and close would accomplish something similar. Close the valves in the tube and when you compress a section of tire, the air cannot escape and distribute through the rest of the tire. As the tire deforms, the tire pressure will rise much faster, offsetting the deformation, just like you had more pressure in the tire.

    Open the valves and you have a regular tire. This system could also be useful for damping the springy suspension of fat tires. I don't know how you would distinguish compression from rebound damping, but it seems possible.

    This would probably be an expensive tube, but the system is tremendously simpler than the adaptec system with a lot more advantages and far lesser energy requirements.

    I've attached a rough illustration.
    Attached Thumbnails Attached Thumbnails Adjust your tires PSI on the fly?-tire.jpg  


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    help

    hello im new at this game and im wondering if any one can help im after some vbrake lugs for my gt zaskar le frame thanks..

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    adjustable tire pressure

    Adaptrac here. I would like to answer any questions you have about our product directly, as I have read some interesting comments on various sites around the world. Enduro races and the fatbike crowds seem to be the most interested. I'm looking forward to your questions.

  35. #35
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    I think most of questions address the added weight of the system and complication added to the bike. Any thoughts on those two issues?
    2010 Giant Yukon FX
    Pure XCR Wheelset/Geax Saguaro Tires/Tubeless
    Bike Weight Lost: 2.48lbs (1124g)

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    Adaptrac

    Agreed. The weight of the system is indeed not to be ignored. I am in the process of lacing up a modified 12 x 142 thru axle power-tap hub. In the coming months, we'll be running climbing segments run both at 30 psi and 60 psi, keeping the power output the same during the climbs. We then can compare the times and come to a true quantifiable advantage of the system. These runs will be entered in Strava under user name Adaptrac so there will be GPS data to substantiate the data. The plan is to prove that by adjusting the rolling resistance to the terrain, your overall power output is reduced below the weight penalty.The advantage it gives you is truly addicting.

    Addressing the perceived complications of the system, we have made improvements. We have reduced the size of the tubing and the way it enters the axle. We don't have to run the un-sightly plastic elbow anymore, as the tubing enters the fitting in axle itself. This reduces the chance of the tubing getting caught on any obstacle. We also have reduced the size and weight of the CO2 regulator. Our tank brackets now have a lower lip to eliminate tank slippage and many mounting holes to facilitate mounting on different frames.

    Thank you for your questions, please keep them coming.

  37. #37
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    Here is the biggest question that's on my mind :
    What is the price that a set is going to sell for ?

    And the 2nd one :
    What does is it weigh ?

  38. #38
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    Adaptrac Prices

    ADAPTRAC SYSTEM COMPONENTS
    MSRP
    Components
    Complete front wheel, 32 Hole, WTB Frequency I23 rim, 15mm Thru Axle
    918 grams 468.00
    Complete rear wheel, 32 Hole, WTB Frequency I23 rim, 12mm Thru Axle 1061 grams $525.00
    Complete front wheel, 32 Hole, Stan's Alpha 340 cross 700c, 15mm Thru Axle 814 grams $488.00
    Complete rear wheel, 32 Hole, Stan's Alpha 340 cross 700c, 12mm Thru Axle 945 grams $545.00
    Titanium Freehub Option -32 grams $88.00
    Dual Control Valve 65 grams $225.00
    Guage Set 0-60psi 45 grams $56.00
    CO2 Regulator 154 grams $168.00


    Refillable CO2 Tanks
    12oz tank 593 grams $22.00
    9oz tank 426 grams $18.00
    4oz tank 295 grams $55.00
    2.5oz tank 403 grams $58.00

    3.3oz disposable 423 grams $4.99


    Thru Axles
    Rockshox Maxle Lite 142 x 12mm Adaptrac Modified $74.00
    Maxle Lite-ABP (Trek)** 142 x 12mm Adaptrac Modified $88.00
    Shimano XTR M988 142 x 12mm Adaptrac Modified $98.00
    Rockshox Maxle Lite 15QR 15mm Adaptrac Modified $55.00
    Fox-Shimano 15QR 15mm Adaptrac Modified $82.00
    DT-Swiss RWS 15mm Adaptrac Modified TBD

    system weight w/o hubs (MT 9oz tank ) 690 grams

  39. #39
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    Too expensive for most.I'll stick with my pump until the prices come down.

  40. #40
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    Quote Originally Posted by supersingle View Post
    Too expensive for most.I'll stick with my pump until the prices come down.
    At 1,500$ for the basic version, I sure agree.

    Add to that the lack of data to back up the claims, and no data regarding the durability either.



    Magura

  41. #41
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    For that kind of money, i would buy a Lezyne HV handpump and a new bike to put it on.

  42. #42
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    Awesome idea for enduro racing but I really dont know if I want more things hanging off my bike!

  43. #43
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    Totally agree Thor29, to much clutter!

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    Adjustable tire pressure

    Keep in mind, you are getting a complete top shelf wheelset, not just the technology. It is not un-usual to spend $1K on a set of complete wheels. These have been tested in extreme conditions (hucking off ledges and such). The rear axle has 5 bearings and a chrome moly axle tube. These are all-mountain hubs.

  45. #45
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    The whole market is going towards tubeless wheels that run lower pressures, because they roll faster. You're trying to sell us a high pressure system that weighs a ton for $1500 that doesnt work well tubeless (co2 hasnt shown to work well with sealant)?

    I hope your data is rock solid and proves the entire industry wrong.. but you've got a HUGE hurdle to jump.

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    Over rocky terrain, yes, running lower pressures prove to be more efficient under certain circumstances. Let's face it, most of us don't have endless, technical singletrack, yards from our door. We have pavement, gravel roads, endless wide fireroad climbs....you get the picture. Under these, less than inspiring sections, 50-60 psi lets you cruise these sections MUCH faster than slogging the mtn bike tires arounud at 30-35 psi. The whole idea is to have the choice....the right pressure for the trail at hand. Please keep the comments coming. We are learning much from your commemnts and concerns.

  47. #47
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    Quote Originally Posted by adaptrac View Post
    Over rocky terrain, yes, running lower pressures prove to be more efficient under certain circumstances. Let's face it, most of us don't have endless, technical singletrack, yards from our door. We have pavement, gravel roads, endless wide fireroad climbs....you get the picture. Under these, less than inspiring sections, 50-60 psi lets you cruise these sections MUCH faster than slogging the mtn bike tires arounud at 30-35 psi. The whole idea is to have the choice....the right pressure for the trail at hand. Please keep the comments coming. We are learning much from your commemnts and concerns.


    If you are going to make any claims you better be able to support those claims.

  48. #48
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    WTF runs pressures that high in their MTB tyres? Not me that's for sure. All I see this as is another way to cater to the lazy people. As mentioned, once you have ANY irregularities on the surface you are riding over it is faster to have a tyre that conforms to the surface, rather than bounces over the obstacles.

    I have no issues what so ever pedaling my bike to the trails on the road running trail pressures, I'm in no hurry and I sure as hell don't want to add 1.5lbs to my overall bike weight either for something I can accomplish with my hand pump in like 2 minutes.

    I can see them selling this to SpecialED though, right up the majority of their customers alleys

    Quote Originally Posted by adaptrac View Post
    Over rocky terrain, yes, running lower pressures prove to be more efficient under certain circumstances. Let's face it, most of us don't have endless, technical singletrack, yards from our door. We have pavement, gravel roads, endless wide fireroad climbs....you get the picture. Under these, less than inspiring sections, 50-60 psi lets you cruise these sections MUCH faster than slogging the mtn bike tires arounud at 30-35 psi. The whole idea is to have the choice....the right pressure for the trail at hand. Please keep the comments coming. We are learning much from your commemnts and concerns.
    One day your life will flash before your eyes, will it be worth watching??

  49. #49
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    Quote Originally Posted by adaptrac View Post
    We have pavement, gravel roads, endless wide fireroad climbs....you get the picture. Under these, less than inspiring sections, 50-60 psi lets you cruise these sections MUCH faster than slogging the mtn bike tires arounud at 30-35 psi.
    Pavement? OK, you will go faster, though I think "MUCH faster" is a bit of an overstatement.

    Gravel roads and fire roads? No, I don't think that you can say that. Personally, I would run my regular (low) trail pressure on these surfaces.
    15mm is a second-best solution to a problem that was already solved.

  50. #50
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    Short of running a near flat tire I cannot see 20psi making any kind of quantifiable difference in rolling resistance on the trail. And very few of us are concerned with the rolling resistance of a tire on the way to and from the trail for two reasons...

    1.) Most of us haul our bikes to the trail by way of car or truck (I for one, dont have a trail close enough to my house to even consider riding to)
    2.) Those of us that do ride on pavement to a trail generally carry an air pump, release the extra psi at the trailhead then replenish it before the ride home. This is accomplished within 2 minutes and at the cost of a $19 mini air pump and a $35 camelbak to carry it in. The mini airpumps weigh at least half as much as your system and most of already wear a hydration pack or can velcro the pump the bikes frame.


    This is in no way meant to offend and I welcome any introduction of new technology into the sport. But, to be succesful in a business you are going to either have one hell of a gimmick (negative ion bracelets for example) or be able to prove to your intended market that what you are selling is indeed an improvement over the current situation and is worth the asking price. So far from the view of a consumer I see niether. Especially after having spent $500 to drop 2.5 lbs from my bike I wouldnt want to spend another $1500 making my current wheelset obsolete and adding 1.5 lbs back to the bike. And since most of the community has already purchased upgraded wheelsets many of us would be in the same boat.
    2010 Giant Yukon FX
    Pure XCR Wheelset/Geax Saguaro Tires/Tubeless
    Bike Weight Lost: 2.48lbs (1124g)

  51. #51
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    I used to put extra air in my tires for road riding, and I've sometimes had paved links or access to trails. Generally, I just leave my MTB tires at their trail pressure and live with it, but I can imagine it being nice to be able to change pressure for those different circumstances.

    I actually don't have all that much trouble visualizing a market for this if you can prove a difference in optimum air pressure for a fire road and for rocky singletrack. I rode with some people in our larger local MTB club the other night. We went to one of my favorite riding spots, a mountain with about 1400' of ridable vert. One of the most popular ways to ride it is to ride up on a fire road, about a thirty minute climb (for an XC geek anyway) and then descend via singletrack, link to some more singletrack via fire road, and take the last singletrack back out to the exit. These guys had ginormous bikes that are heavy even when they cost as much as my car, rode up helmetless taking about an hour, and then put on their helmets and shin guards for the descent. I think some of them had dropper posts, and they all had all kinds of knobs and switches on their suspension.

    While I don't see myself as a customer for a product like this anytime soon, there's certainly people who don't mind having to mess around to switch modes, stop and start a lot, and spend money making their bikes heavier. You just need to show some advantage for the climbs and road links that they might have between trail sections, or for different pressures on different singletrack surfaces.
    "Don't buy upgrades; ride up grades." -Eddy Merckx

  52. #52
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    Quote Originally Posted by One Pivot View Post
    The whole market is going towards tubeless wheels that run lower pressures, because they roll faster. You're trying to sell us a high pressure system that weighs a ton for $1500 that doesnt work well tubeless (co2 hasnt shown to work well with sealant)?

    I hope your data is rock solid and proves the entire industry wrong.. but you've got a HUGE hurdle to jump.
    Good point that it needs to work with tubeless sealant.
    15mm is a second-best solution to a problem that was already solved.

  53. #53
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    Quote Originally Posted by AndrwSwitch View Post

    While I don't see myself as a customer for a product like this anytime soon, there's certainly people who don't mind having to mess around to switch modes, stop and start a lot, and spend money making their bikes heavier. You just need to show some advantage for the climbs and road links that they might have between trail sections, or for different pressures on different singletrack surfaces.
    The only crowd who would benefit from this contraption because they don't mind to muck around, spend a boatload of money and (generally) dont't give a toss about the weight of their bikes that i can think of are Fatbikers.
    Of who i am one.


    But i don't think i will be using a set up like this any time soon.
    Because it adds more gear that potentialy can break down and it costs a lot of money.
    And with the tirevolume on a Fatbike you would probably nead a tank the size of a oxygentank that divers use.

  54. #54
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    Quote Originally Posted by AZ.MTNS View Post
    If you are going to make any claims you better be able to support those claims.
    I sort of hoped the claims would be backed up, now that the manufacturer joined the thread.

    I for one would be very interested in seeing some hard data regarding this topic.


    Magura

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    Were lacing up the modified 12mm thru axle Powertap now. We'll be riding all over and posting 25 vs. 55 psi climbs on Strava under user: Adaptrac keeping power output the same, comparing times.

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    The Schwalbe tyre study looked at how tyre pressure affects rolling resistance:

    It found that rolling resistance on gravel and grass (meadow) was lower when the tyres were run at lower pressures. The tyres had lower rolling resistance at higher pressures on tarmac:

    MTB power meter thread.

    http://www.mtbonline.co.za/downloads...llustrated.pdf

    Looking at my Powertap files from different rides, where I know that I've used the same tyres with different tyre pressures (20psi for offroad rides or 50 psi for road rides) and ridden along the same section of gravel path each time (i.e. riding along the cycle track or canal towpath) it seems to roughly agree with that. On tarmac I'm usually quickest when the tyres are pumped up to 50 psi but then on gravel I'm a little quicker with the tyres at the lower pressure of 20psi.

    eg:
    25 May 2012 - 20 psi tyre pressure, 1.3 miles on gravel cycletrack, Time 5 min 17 sec, 14.8mph average speed, 172 watts average power
    26 June 2012 - 50 psi tyre pressure, 1.3 miles on gravel cycletrack, Time 5 min 32sec, 14.1mph average speed, 167 watts average power

    Trying to produce any sensible conclusions with a Powertap can be fairly tricky to do. It's really difficult to ride at exactly the same power output each time. In these short extracts from ride files for example I was 5 watts different on average power which makes a difference. When riding outdoors wind has a big impact too. This was a fairly sheltered section so shouldn't be too bad but I don't have a note of the wind at that point for each ride.

    You probably want to do lots of runs with each tyre pressure and then average them which would give a better idea. That's what I did for my 26" Specialized Epic v 29er Specialized Epic climbing comparison where I went back through my old files.

    2011 S Works Epic 26er v 29er

    Pictured below The impact of tyre pressure on rolling resistance on gravel, meadow (grass) and tarmac from the Schwalbe tyre study.
    Attached Thumbnails Attached Thumbnails Adjust your tires PSI on the fly?-tyre_pressure_offroad.jpg  


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    WR304

    Thank you for posting this. I read this a while back when doing research. I wish he had run a fourth hardpack dirt catagory, as most of our riding around here is that. Is it more like tarmac or gravel as far as rolling resistance?

  58. #58
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    Hardpack dirt would be somewhere in between gravel and tarmac.

    I would like to suggest a somewhat more controlled test, as just running a power meter, and uploading the Strava figures, does not make much of a result in terms of hard data, but rather would create basis for further discussion of the merits of the system itself, no matter the outcome.
    With so many variables, and none of them accounted for, the result of such uncontrolled test, would be what is known as anecdotal evidence.

    How about picking some of the engineers from Bike magazine's results, and work your way from there?
    They did as I recall test the basic rolling resistance of a few tires a while back. Now if you pick one of those tires, you at least have a starting point.
    You would also be able to look into their test protocol, and see if it is reasonably free of flaws. If so, you even have a protocol sorted with little effort.

    Teaming up with a tire manufacturer, just might be a solution as well, since they too must have some test facilities, and a reasonable protocol.

    If you decide to do the test on your own, at least do it under a reasonably correct protocol, and eliminate as many variables as possible.

    Just a thought.....


    Magura

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    Mr. M

    Agreed. I'd like to present as solid, reliable and cohesive data as possible.

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    Quote Originally Posted by AZ.MTNS View Post
    That swivel connection on the side will last about 13 nanoseconds before it is ripped off with a resounding "woosh" and then you be walkin.
    pretty sure they didn't remove the valve from the tube/rim. So while the system would be rendered useless it wouldn't delate the tire.

  61. #61
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    Quote Originally Posted by Fleas View Post
    A buddy of mine with a Pugsley asked me about this years ago ("like a Hummer", he said). Fat bike tire pressure is a little more of an issue esp. if you are on mixed terrain like hard to sand, or frozen to snow. The benefits of pressure changes are instantly realized.

    I'm sure these guys will integrate the system a lot better and someday the seat post or the handlebar or something will double as the compressed air canister. Heck, they could build a shock absorbing seat post that pressurizes a reservoir while you bounce down the trail.

    I'd like to see if the system doesn't leak, though. Rotating air seals are a tricky business. The stock fittings on the outside are pretty reliable, but I wonder more about the internals of the hub.

    Very cool idea!

    -F
    Perhaps you could do a system for fattys that could be contained within the wheel. Mount a pair of 25g CO2 cartridges to the rim/spokes and have a wireless control and the system would be pretty contained and out of harms way. You'd probably want to do a pair of these on opposite sides of the wheel to keep it balanced.

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    Quote Originally Posted by customfab View Post
    Perhaps you could do a system for fattys that could be contained within the wheel. Mount a pair of 25g CO2 cartridges to the rim/spokes and have a wireless control and the system would be pretty contained and out of harms way. You'd probably want to do a pair of these on opposite sides of the wheel to keep it balanced.
    I wonder what kind of nastyness would ensue if you snake bit a tire directly on one of the co2 cartridges.
    2010 Giant Yukon FX
    Pure XCR Wheelset/Geax Saguaro Tires/Tubeless
    Bike Weight Lost: 2.48lbs (1124g)

  63. #63
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    Quote Originally Posted by adaptrac View Post
    Mr. M

    Agreed. I'd like to present as solid, reliable and cohesive data as possible.
    It might be worthwhile looking into a testing centre such as Wheel Energy.

    Home - Wheel Energy Laboratory

    Bicycle Tires ? Puncturing The Myths - BikeRadar

    .

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