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  1. #1
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    Wide Rims? Don't believe the hype...

    Hi Folks,
    After researching the subject of rim specs for DH wheels, I find that wider rims are becoming increasing popular. News Flash, right? No, not really, but I have begun to wonder just how much of this is simply hype. Let's be honest and see if there are some facts we can look at before I even give my opinion:

    1) Many of the most popular tires with consistently good reviews (i.e. Maxxis Minion DHF) have casings that were designed before manufacturers were building these 'wide' rims with >25mm internal width.
    2) Many of the top racers use rims with less than 25mm internal width.

    Really? You mean the really fast guys don't ride on wide rims? Why not? I know from personal experience that 'wide' rims feel different, but honestly I don't know if they make me faster. So: I think it is all hype. My guess is that the ideal rim width for DH tires on the market today is 23mm - 25mm of internal width.

    2013 winning riders
    1. Steve Smith Easton Havoc 23mm
    2. Greg Minnaar - Enve DH 21mm (30mm external)
    3. Aaron Gwin DT FR600 24.9mm


    Ive ridden these rims on Freeride, DH Racing and DS:
    1. Crossmax SX 21mm
    2. Atomlab Standard Issue 21mm
    3. Atomlab Pimp2 26mm
    4. Specialized Roval DH 23mm



    Unrelated, but Ive ridden DT Swiss m480 for All Mountain
    DT m480 19.6mm

    My opinion: I notice a different feel when moving from 21mm to 23mm rims (internal width) and I up the psi a bit on the rearbut I don't know if it is actually better traction or just a different feel. My experience is far from a controlled experiment. I don't even really notice the different from 23mm to 26mm.

  2. #2
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    A greater difference will be felt when running thinner, AM or XC tires at lower pressures.

    Yes, I designed the DHR2 and the HR2 on a 23mm internal width rim, but the difference in profile going from 23mm to 28mm internal isn't much.
    Tire Design & Development Engineer. The opinions expressed in this forum are solely my own.

  3. #3
    nvphatty
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    we are not all racers or wanna be racers but mere plain recreational riders by in large so much of what you posted does not apply nor will effect the vast majority.

  4. #4
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    that's a broad proclamation on a pretty weak basis.

    here's an idea: why not ride what you like and what works for you, regardless of what Smith and Minnaar are riding?
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
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  5. #5
    The Fastest of Bananas
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    I can tell the difference between a 21 and a 30.

    However, for I run 21mm on my AM bike. Its does just fine with beefy tires, but i could run a lighter tire on a wider rim. DH is much different than trail riding. They run much stronger but heavier tires that really dont care what rims they are on. Also, going very wide can squared out the profile of the tire, which is a bad thing when you lean the bike 60+ degrees

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  6. #6
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    We all have different objectives so whatever works...

    I noticed a difference between running 19mm (Stan's 355) and 21.?mm (Stan's Crest) internal width rims with the same tires mounted on them.

    I have 3 sets of "28mm" rims (~23 ish mm internal width) as well and do not notice as much of a difference with the same tire mounted on them as compared to the Crest's. All of them are setup tubeless.

    I even run a 3.0 Knard 120 tpi front tire mounted on a "28mm" rim (rigid single speed 36x18). It makes the rim look like a road wheel with all the tire volume. Quite effective cushion (@ ~12 psi with a bit of added weight and +2-3 cog teeth to pedal it on the climbs I was doing with a 2.4 front tire/15t cog).

  7. #7
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    Quote Originally Posted by oldranger View Post
    2013 winning riders
    1. Steve Smith Easton Havoc 23mm
    2. Greg Minnaar - Enve DH 21mm (30mm external)
    3. Aaron Gwin DT FR600 24.9mm
    Don't forget these guys have to run their sponsor's equipment, and many of the mainstream manufacturers have not gone to the wider rims (partially due to old rim safety specifications).

    Additionally, the world's top pro riders would kick ass on most any bike/setup you stick under them.

  8. #8
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    I've never seen anyone claim that wide rims are faster, so I don't see the relevance. The benefit most often cited is the more traction through the use of lower pressures. I doubt any DH racers are willing to risk using lower pressures. On the odd occasion I enter an enduro race, I definitely add pressure to my tires.

  9. #9
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    Quote Originally Posted by bholwell View Post
    Yes, I designed the DHR2 and the HR2 on a 23mm internal width rim, but the difference in profile going from 23mm to 28mm internal isn't much.
    Thanks bholwell! This is the kind of information I was hoping to get out of this thread!

    Note: I didn't intend this to be a discussion on what 'I liked to run' or what 'is fun for me' since that doesn't really matter to you (folks). I hoped to initiate (or instigate) a debate on the actual performance value of wider rims. I haven't found (anywhere) where an engineer or product team has substantianted that a rim wider than 23mm (internal) helps improve riding or how a tire provides traction. On the flip side I see that wider rims increase material and weight, or they require expensive materials....all of which are a drawback in my mind.

  10. #10
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    Quote Originally Posted by mtnzj View Post
    Don't forget these guys have to run their sponsor's equipment, and many of the mainstream manufacturers have not gone to the wider rims (partially due to old rim safety specifications).

    Additionally, the world's top pro riders would kick ass on most any bike/setup you stick under them.
    I totally agree. But I was honestly surprised when I researched what they are riding - and learned they are NOT running the trendy wide rims.

    Look folks. My bike is not spec'd with what the racers are using simply because it is what they are using. I have Atomlab wheels, a Marz 888 fork, low-end cranks, a heavy-a## seat, and the list goes on...but if I am going to spend money on improving my bike it seemed like wheels were the way to go. So I started looking at what credible riders are winning on.

  11. #11
    The Fastest of Bananas
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    Re: Wide Rims? Don't believe the hype...

    Quote Originally Posted by oldranger View Post
    Thanks bholwell! This is the kind of information I was hoping to get out of this thread!

    Note: I didn't intend this to be a discussion on what 'I liked to run' or what 'is fun for me' since that doesn't really matter to you (folks). I hoped to initiate (or instigate) a debate on the actual performance value of wider rims. I haven't found (anywhere) where an engineer or product team has substantianted that a rim wider than 23mm (internal) helps improve riding or how a tire provides traction. On the flip side I see that wider rims increase material and weight, or they require expensive materials....all of which are a drawback in my mind.
    Wide rims dont directly provide traction, they enable lower pressures that provide more traction.

    Do you really notice 50g in a rim? Tire choice is almost infinitely more important.

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  12. #12
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    Quote Originally Posted by FastBanana View Post
    Do you really notice 50g in a rim? Tire choice is almost infinitely more important.
    Thanks for your points on how rim width can influence psi (and traction). I don't recall mentioning 50g, but for the sake of discussion:

    I run a 630 gram Atomlab Pimp2 rim because I was encouraged to build a wide, tough rim for DH. If I go with a smaller rim profile I can get closer to 500g. The top end Norco, Devinci and Specialized DH bikes are spec'd with rims that weigh about 500g and are close to 23mm internal width. (I think; just picking from some brands)

  13. #13
    It's about showing up.
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    This has been said about many "advancements" in bike technology. The challenge is that measuring it's effect is elusive. Its sort of like taking 20 grams off of a derailleur; an incremental step I may not even feel. Add to that I'm just trying to stay upright most of the time.

    But, when you take a look at an entire Groupo the weight difference adds up. And, seen from my 1988 Rigid 6 Speed Rockhopper with cantis, all those incremental steps add up, too.
    I don't rattle.

  14. #14
    The Fastest of Bananas
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    Thats the difference between an Arch and a Flow rim.

    630g rim is just plain overkill. There is a reason those bikes are spec'ed with 500g rims. Its a great balance point, and 23mm is by no means a thin rim. At that weight/width, you have a very strong wheel.

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  15. #15
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    I find rims over @23-25mm internal width start to take a heck of a lot more hits on rocky trails (from the volume and also dings to the finish)
    video=youtube;][/video]...

  16. #16
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    Quote Originally Posted by nvphatty View Post
    we are not all racers or wanna be racers but mere plain recreational riders by in large so much of what you posted does not apply nor will effect the vast majority.
    love what is said here. this forum consists of recreational riders...not many pros if any. Though it's great these guys do so well, etc. I couldn't give a wild smelly crap about who rides what. I want good wheels that feel great on my ride....and I'm a damned good rider. But I don't pretend to be a pro or anything similar.
    I have too many bikes, but it's not enough

  17. #17
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    I ride a full rigid, what pro DH and FR riders run means jack schitt to me (and most riders).

    My experience with single ply tires is that big volume tires on narrow rims roll when cornering unless I pump them up harder than I prefer. So I like wider rims with big tires that I can run down to ~18psi for traction and some cushion.

  18. #18
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    Wide Rims? Don't believe the hype...

    I personally like wider rims for running lower pressure and getting better traction and less tire squirm.
    Are you going to tell me this is all in my head?


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  19. #19
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    ^ This! Bike Whisperer wins the prize for best answer!
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  20. #20
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    Re: Wide Rims? Don't believe the hype...

    Quote Originally Posted by MTBMILES View Post
    I personally like wider rims for running lower pressure and getting better traction and less tire squirm.
    Are you going to tell me this is all in my head?


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    Its great for running over chihuahuas
    ....with less tire squirm

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  21. #21
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    Meh, my wide rims are awesome. I dont care what pro's run, I'm not a pro.
    I like to fart when I'm in front of you on a climb

  22. #22
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    Quote Originally Posted by MTBMILES View Post
    I personally like wider rims for running lower pressure and getting better traction and less tire squirm.
    Are you going to tell me this is all in my head?
    I dunno. My hypothesis (for the sake of debate) is that the ideal rim width for standard 2.3-2.5 width DH tires on the market today is 23mm - 25mm of internal width. I looked for any shred of evidence to the contrary, and didn't find any. Maybe when tires are squirming psi is sub-optimal, and addressing it with wider rims doesn't solve the root of the problem.

  23. #23
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    Wide Rims? Don't believe the hype...

    Quote Originally Posted by FastBanana View Post
    Also, going very wide can squared out the profile of the tire, which is a bad thing when you lean the bike 60+ degrees
    lol... when you're leaning your bike over 60(+) degrees... good one.

    also... tire profiles are round... always.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  24. #24
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    Wide Rims? Don't believe the hype...

    Quote Originally Posted by oldranger View Post
    I looked for any shred of evidence to the contrary, and didn't find any.
    That being pros' equipment choices?
    Just out of curiosity, how did you arrive at your claimed optimal rim width?
    And what is sub-optimal about riding a tire pressure that works? Isn't optimum tire pressure totally dependent on the circumstances, including rim width, or have you also figured out optimum tire pressure for everyone on every bike?
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  25. #25
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    Quote Originally Posted by meltingfeather View Post
    Just out of curiosity, how did you arrive at your claimed optimal rim width?
    To your question: I based my hypothesis largely on the observation that the majority of the major manufacturers spec their best DH bikes with 23mm-25mm rims, and many of the DH racing teams use the same. I had no access to wheel manufacturer test data. They do. A hypothesis is a speculative guess that has yet to be tested.

    That said, after a day of interesting comments, Id like to restate my hypothesis because I think some of you missed it: the ideal rim width for DH tires on the market today is 23mm - 25mm of internal width. I started this thread in hopes there would be attempts to prove or disprove itwhich in turn, help me make a good decision on a pair of wheels for my DH bike. I recognize its not a well justified hypothesis, and the word ideal oversimplifies thingsbut the point Im making has not been disproven in this thread. On the contrary, a tire designer seems to (indirectly) support it and that is the only professional opinion so far on the thread. Maybe I should try to elaborate a bit on what I mean by ideal: I mean compatible with, and works optimally in conjunction with a conventional DH tire (2.3-2.5 DH casing) to provide the best possible traction for the rider without adversely impacting speed or durability. Ideal for DH is not: wide enough to enable dramatically low psi so the rider doesnt perceive slip on rocks and roots and such. Or worseso the rider can sit down comfortably.

    Lets not dumb this down. I threw this topic out in a forum dedicated to Wheels & Tires. This discussion isnt about preference, or Recreation vs. Racing, or how something feels. I consider myself a recreational rider. But frankly folks if you are a recreational rider sitting on a $4-8K DH bikeyoure sitting on a sophisticated, carefully specd piece of equipment. And most of you try to go fast (I hope). Me personally: I dont want to ignorantly do the equivalent of throwing a big ass set of Dubs on a BMW M3 just because of some hype around WIDE is BETTER and manufacturers like I9, Atomlab, Spank, etc. wanting to sell us those things. It is a common play to penetrate a market with gimmicky products that owners cant find as OE on some car or truck or gun or bike under the premise it is better.

    Here are the observations I have that seem to contribute to this topic.

    Major Manufacturer DH Bike Spec:
    Trek Session FR600 (24.9mm)
    Devinci Wilson, Norco Aurum LE, Transition TR450 Easton Havoc DH (23mm)
    Specialized Demo 8 Roval 30mm external (usually means about 23mm internal)
    GT Fury E13 LG1+ DH (23mm)
    Giant Glory 0 DT Swiss EX500 (20.7mm)
    Successful Racing Team Rim Choices:
    Steve Smith Easton Havoc (23mm)
    Greg Minnaar - Enve DH 21mm (30mm external)
    Aaron Gwin DT Swiss FR600 (24.9mm)

  26. #26
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    Quote Originally Posted by meltingfeather View Post
    Isn't optimum tire pressure totally dependent on the circumstances, including rim width, or have you also figured out optimum tire pressure for everyone on every bike?
    Absolutely. Tire pressure is the variable that the rider should change based on conditions. No. I haven't made any claims about psi, nor have I stated that I've figured out anything.

  27. #27
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    Wide Rims? Don't believe the hype...

    Fine, but your OP wasn't carefully caveated and specific like your last post. It's easy to miss your point when you don't make it. The OP was a broad claim about wide rims being all hype, and used a fairly small sample based on pro DH riders as the supporting evidence.

    Your OP mentions that you're looking at DH rims, but that's the only hint that the discussion of rim width was intended to be limited to that narrow application. Besides, most of the wider is better talk that would be interpreted as hype comes from the trail-AM market where you have Stans and WTB and Syncros playing.

  28. #28
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    Wide Rims? Don't believe the hype...

    I have noticed wheel sizes changing and bikes have disc brakes, droppers and FS. I have a feeling rims widths are also evolving.


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  29. #29
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    Quote Originally Posted by evasive View Post
    Fine, but your OP wasn't carefully caveated and specific like your last post. It's easy to miss your point...
    Progressive elaboration. And c'mon...the acronym "DH" is in my first sentence. Now do you have something to contribute that disproves my hypothesis Mr. Evasive, or are you just looking to easily increase your post count with a debate? Please do some research.

    Quote Originally Posted by evasive View Post
    Besides, most of the wider is better talk that would be interpreted as hype comes from the trail-AM market where you have Stans and WTB and Syncros playing.
    OK, I hadn't thought about where the hype was coming from. For what its worth, I bought Stans Flow EX for my son's DH bike...believing the hype applied to DH. The 2.5 Maxxis Minion DHF tire profile on that rim is absolutely different than it is on my Crossmax SX or My Atomlab Standard Issue. Which is better? (I don't know, hence my hypothesis and provocative posts and title)

  30. #30
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    Wide Rims? Don't believe the hype...

    Have you not ridden the different widths to come up with a conclusion based on riding?


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  31. #31
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    Quote Originally Posted by MTBMILES View Post
    Have you not ridden the different widths to come up with a conclusion based on riding?
    Yes, but as I mentioned in my original post...I couldn't get to any conclusion about what is really faster. I've ridden rims from 21mm 26mm (internal width) in many places across North America, as fast as I can go. But my opinion isn't worth much so I started looking for credible information.

  32. #32
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    Wide Rims? Don't believe the hype...

    I think better traction equals more confidence leading to faster times. That is my conclusion based on my riding.


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  33. #33
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    Quote Originally Posted by oldranger View Post
    I started this thread in hopes there would be attempts to prove or disprove itwhich in turn, help me make a good decision on a pair of wheels for my DH bike.
    You know what would be a much better basis for a decision than theoretical arguments on the internet? Finding some wide rims to borrow/demo and see what you think.
    Quote Originally Posted by oldranger View Post
    On the contrary, a tire designer seems to (indirectly) support it and that is the only professional opinion so far on the thread.
    I think you have misinterpreted his comment somewhat.

    Hypotheses are part of the scientific method. You aren't using any scientific methods. You are attempting to confirm your bias by searching out anecdotal evidence that you interpret to support your idea. No isolation. No control. It is meaningless.
    You can't prove whether something is "all hype" or not. First, what does that even mean? Second, you'll never have enough data to say anything statistically significant, and even if you were able to put all that together, it would not tell you what your individual experience is going to be on any given rim width. That's why it makes sense to cut all the BS and just ride some wide rims and see what you think. It would also be a whole lot more fun, unless posting here is more fun to you than riding.

    Quote Originally Posted by oldranger View Post
    Lets not dumb this down.
    It started off dumbed down. Why change now?

    At some point you have to realize that your, from a scientific standpoint, totally hack efforts at really "figuring something out" aren't going anywhere. Riding a bike for the sake of it is about doing what works for you, which riding the bike will tell you. Doing otherwise is posing.
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  34. #34
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    Mr. Feather,
    Do you have some objective observations or proposed investigation that constructively adds to this? Do you suggest a specific rim or rim width based on your own observations?

    This is a hypothesis, not a theory, so you can back down on "start doing some science" rant. I don't pose. I'm not a professional I don't have a good opinion. Don't get so easily bent out of shape on how I instigated folks to contribute to this thread

    A hypothesis is defined as: a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.

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    Quote Originally Posted by meltingfeather View Post
    that's a broad proclamation on a pretty weak basis.

    here's an idea: why not ride what you like and what works for you, regardless of what Smith and Minnaar are riding?
    Word.

    Based on feedback from others and reflection on my personal intended use and preferences I decided on a set of Pacenti TL28 29er rims to replace the stock wheels on my 2009 Giant XTC 29er 1.

    I don't know if I'd go so far as to call it "hype" but I would say they lived up to my expectations based on other users feedback. (IMO WIDE carbon rims are "hype.") The Pacenti TL28 29er are reasonably light. I can run low pressures with them (20psi F and 22psi R on my pump) and haven't pinch flatted on them, with tubes (passed plenty of people in the Shenandoah 100 who did pinch flat on the rocks for whatever reason so I know my setup works for me). And at those pressures they offer good tire stability. But this is only my second set of MTB rims, so I have no valid comparison. All I can say is they work for me, other users experience might be different based on their intended use, riding style, and priorities. So do your research and make an informed decision.

  36. #36
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    Quote Originally Posted by meltingfeather View Post
    You know what would be a much better basis for a decision than theoretical arguments on the internet? Finding some wide rims to borrow/demo and see what you think.
    OK. Done. I have two seasons of DH racing on a set of Atomlab Pimp2 rims with 2.5 Minion DHF front and rear; sometimes High Rollers. I have not substantially changed my approach to psi while using these rims. These rims have a 26mm (WIDE) internal width

    I have 6 days of sustained riding at Whistler on the same bike, but with rims that had a 23mm internal width.

    I can't tell the difference. Should I stick with a 23mm rim or go with a wider one? if so why? If you want to make this about me (like your attacks on my words in this post)...I'm 190-195lbs riding weight, I ride fast and want to go as fast as I can. What rims should I consider?

  37. #37
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    (This is fun by the way - I do appreciate the responses. There have been some meaningful comments) (Thank you)

  38. #38
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    Quote Originally Posted by oldranger View Post
    Mr. Feather,
    Do you have some objective observations or proposed investigation that constructively adds to this?
    Yes. Riding will tell you all you need to know about what equipment choice will work for you.
    Quote Originally Posted by oldranger View Post
    Do you suggest a specific rim or rim width based on your own observations?
    I know what works for me, which is of no use to you.

    Quote Originally Posted by oldranger View Post
    This is a hypothesis, not a theory, so you can back down on "start doing some science" rant. I don't pose. I'm not a professional I don't have a good opinion. Don't get so easily bent out of shape on how I instigated folks to contribute to this thread
    Not at all bent... I just offered my opinion, which is what you asked for. Don't like it? Don't heed my advise.

    Quote Originally Posted by oldranger View Post
    A hypothesis is defined as: a supposition or proposed explanation made on the basis of limited evidence as a starting point for further investigation.
    Cute. I know what a hypothesis is. I'd say, as others have, that what I ride and for that matter what sponsored pros ride is of little value in determining "optimal" for you.
    Good luck
    Quote Originally Posted by pvd
    Time to stop believing the hype and start doing some science.
    29er Tire Weight Database

  39. #39
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    there's too much time on your hands. go ride your bike.
    I have too many bikes, but it's not enough

  40. #40
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    Sure seems like oldranger=Traildoc. For those who didn't follow the Az forum Traildoc was an avid rider, trail-builder and troll. Who was temporarily banned from the local Sedona forest and then banned from MTBR. There is way too much good information on this forum let's keep the good exchange and forget the trolls.
    hojo

  41. #41
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    Bike manufacturers spec bikes to fit the average rider. It's up to you to figure out where you fit in relation to the average. In my experience, being heavier and more aggressive than the average rider, a wider and heavier rear rim lasts longer. Is 600 grams overkill? Not for me (185 lbs, former expert dh racer), unless I want to rebuild the rear wheel 1 or more times per season.
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  42. #42
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    Quote Originally Posted by HoJo View Post
    Sure seems like oldranger=Traildoc.
    hojo
    Still hoping for someone to give specifics on rim widths outside of the 23mm - 25mm range for DH.

    Too funny. Trail doc? Really? I'm just a 42 year (Old) guy who has been a Ranger (Ranger) Old+Ranger = OldRanger. You guys really stink at science and math.
    Last edited by oldranger; 02-25-2014 at 01:07 PM. Reason: cleaned it up a bit. c'mon really guys...

  43. #43
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    Quote Originally Posted by dbabuser View Post
    In my experience, being heavier and more aggressive than the average rider, a wider and heavier rear rim lasts longer. Is 600 grams overkill? Not for me (185 lbs, former expert dh racer), unless I want to rebuild the rear wheel 1 or more times per season.
    Thanks. Do you run a lighter rim in the front? I've considered that option.

  44. #44
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    I've had good luck w/ 500g front rims on my dh bike.
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    Thanks dbabuser. This is helpful, I haven't tried a 'staggered' setup...but wondered if it would be a good approach for DH riding given the typical weight distribution front/rear the rider has. It's also helpful for me to have your benchmark for a 185 pound rider - that's about where I am. I have seen others with this approach

    For anyone (like me) who may be new to this topic of rim widths, or rim design in general - let me try to elaborate on the relationship between dbabuser's observations on rim weights and rim widths (simple, I know). Generally speaking rims with 21mm internal widths can be built in the 500g range (i.e. DT Swiss EX500). Rims with a 25mm internal width can generally be built in the 600g range (i.e. DT Swiss EX600). I use the DT Swiss example since they are kind enough to put the rim weight in the product name.

    Disclaimer: this doesn't always hold true. One contrast is the Stan's Flow EX which has a 25.5mm inner width, but only weights 500g.

  46. #46
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    Quote Originally Posted by oldranger View Post
    Yes, but as I mentioned in my original post...I couldn't get to any conclusion about what is really faster.
    You keep saying faster. Its not always about "faster" for non-racers. I like the wider trend because the tire is more stable at lower pressures.

  47. #47
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    Quote Originally Posted by MTBMILES View Post
    I personally like wider rims for running lower pressure and getting better traction and less tire squirm.
    Are you going to tell me this is all in my head?


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    I don't run 26er downhill tires. I do however run 29er 2.4 tires on 35 mm ID rims and they are awesome at lower pressure and maximum traction. Wider = better for tubeless, YRMV.

  48. #48
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    With the modern frames and drive for short chain stains with bigger wheels (27.5) that are sometimes stuffed in smaller frames (HDR ) the width of the rim can be a problem with the fit in the rear. Manufacturers already spec narrow 2.2 tires for tight clearance so going wider might not be an option
    On the other hand I agree with op For modern 2.4 -2.5 tires the internal width of 23-25 mm is optimal for weight and performance. And I can run low pressures on ust rims of that width too , so why carry extra weight for 35-40mm internal big rim. That's unless we go to 2.7 or 3.0 tires , oh wait - that's fat biking

  49. #49
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    Quote Originally Posted by Ilyam3 View Post
    That's unless we go to 2.7 or 3.0 tires , oh wait - that's fat biking
    no thats not close to fat biking, 3.8 begins fatness. When i build my next full squish AM bike it'll use 35mm blunts with the 26" 2.75 dirt wizards which will equate to 27.5 circumference wise.

  50. #50
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    Wide Rims? Don't believe the hype...

    Carbon rims are lighter than tires. So use a wider rim and a more narrow tire to get a similar effect as a fat tire and a narrow rim for less weight.

    Simple.


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  51. #51
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    Road bikes.
    Motorcycles.
    Cars.
    Zamboni.
    Wheelbarrows.
    Unicycles.
    Wheelchairs.
    Space Shuttles.
    GoKarts.
    Mars rover.
    Trailers.
    Hand trucks.
    Lawnmowers.
    Aircraft.
    Strollers.
    Tractors.
    R/C anything.
    Golf carts.
    Heavy equipment.
    ATV's.
    UTV's.
    Monster trucks.

    DID I MISS ANY?

    NOT ONE of these rubber tire equipped machines utilizes a rim width that is narrower (by much of a margin) than the tire it is supporting... COINCIDENCE?

    Why believe the hype when you can look at the facts?

    Oh, and dont believe the hype, 9ers dont ride faster and suspension will actually slow you down from all the pedal bob....

  52. #52
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    Quote Originally Posted by ryanxj View Post
    DID I MISS ANY?

    NOT ONE of these rubber tire equipped machines utilizes a rim width that is narrower (by much of a margin) than the tire it is supporting... COINCIDENCE?
    Yes, I think you missed one: Motocross. I don't have one, but those machines still use tires with a rim width that is narrower than the tire it is supporting. It looks like the margin is greater on the front. But I'm way out of my knowledge 'base' on this MX comparison.

    But you could also add one to your list: BMX Bikes. Those tires seem to be fairly close to the rim width. Wait, let me clarify: those 20" tires that roll on hard pack or paved dry surfaces have tires with a casing width close to the rim width. Hmmm. I wonder when BMXers will go to full suspension 29ers cause they ride faster?

    Your comments where thought provoking - so thanks for that!

  53. #53
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    Link to another post on here that has some relevance to this subject:
    Tire height vs. rim width

  54. #54
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    I found some more related posts

    Try this one:
    Rim Width - How Wide is Too Wide?

    A quote from that thread:
    Quote Originally Posted by Norman Clydesdale View Post
    As the rim's interior width increases, you'll see different performance and appearances in your tires. Basically, the same tire will sit and perform differently on a narrower rim vs an even slightly wider rim...On a 25mm inner width rim, the tire sits noticeable squarer and hooks up better in corners in all conditions. I can run it tubeless at 32psi in the front and 36 in the rear and not worry about burping or dinging the rim. If I run just a few psi lower in a tubeless set up on the 25inner width rim, I'll ding and flat spot the rims.
    So, you'll need to factor in PSI, tire size, and rim width in to the equation. Depending on tire choice and preferred PSI, I think you can go too wide in rim width. In my experience,25-23mm inner width seems to be a good spot for many trail tires in the 2.4-2.3 range. Just a few mm increase in inner rim width can produce positive performance results.

  55. #55
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    Quote Originally Posted by oldranger View Post
    Try this one:
    Rim Width - How Wide is Too Wide?

    A quote from that thread:
    32 / 36 PSI is quite high pressure for a large percentage of riders ... Norman Clydesdale implies 200+ lb. rider and based on what he stated, there wasn't much room to lower the tire pressure without dinging the rims.

    Some other factors to consider besides PSI, tire size and rim width:

    Tubeless system
    Tire sidewall thickness
    Rider weight
    Riding style
    Terrain

    I am 195 lbs. and ran 20 psi F / 25 psi R "semi-aggressively" on Stan's 355 rims with TLR Schwalbe Racing Ralph tires (2.4 front / 2.25 rear) setup tubeless w/ Stan's goo and rim tape. I manged to burp the front once on a severe down and up that was off camber (with a bit of a turn). That was the only time I've ever burped a tubeless tire in years of riding on them.

    I can run 17 PSI on the front with a wider Stan's Flow rim running with a Schwalbe Nobby Nic snakeskin 2.35 tire. I typically run a Racing Ralph 2.4 a few PSI higher on the front...

    My approach to setting up appropriate tire pressure is:

    Front- start in mid 20's, drop 1 PSI at a time and ride a bit until handling in significant turns becomes squirmy, then add 1-2 psi.

    Rear- start around 30, drop 1 PSI at a time and ride a bit until I detect something close to a rim hit when riding over rocks/roots at a moderate pace, then add 1-2 PSI.

  56. #56
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    People, you are forgetting one important reason to run wide rims.

    The sheer surface area you get for flashy colors!


  57. #57
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    Quote Originally Posted by oldranger View Post
    Yes, I think you missed one: Motocross. I don't have one, but those machines still use tires with a rim width that is narrower than the tire it is supporting. It looks like the margin is greater on the front. But I'm way out of my knowledge 'base' on this MX comparison.

    But you could also add one to your list: BMX Bikes. Those tires seem to be fairly close to the rim width. Wait, let me clarify: those 20" tires that roll on hard pack or paved dry surfaces have tires with a casing width close to the rim width. Hmmm. I wonder when BMXers will go to full suspension 29ers cause they ride faster?

    Your comments where thought provoking - so thanks for that!
    What part of 'motorcycles' excludes MX? and I'm not sure on bmx stuff myself, but if they are using narrow rims, i would have to assume that its purely a matter of shaving grams, as is likely @ the top level of dh racing. Not to mention, if assume that the smooth groomed nature of a bmx track allows for highish pressures, lessening the benefits of a wider rim/tire interface...

  58. #58
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    I guess this thread means my Sun Rhyno Lites are back in style!

  59. #59
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    Quote Originally Posted by Saul Lumikko View Post
    People, you are forgetting one important reason to run wide rims.

    The sheer surface area you get for flashy colors!

    Ding, ding, ding...winning

    1994 called and wanted it's wide rims...just need some nice green hubs
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    Most of the expansion has to do with the relatively recent tubeless tire trend. Burping will occur more frequently on older rim tire combos because neither were designed for the task. Primarily because a narrow tire base generally leads to a taller thinner tire when inflated. Think narrow at the bottom and wide at the top... Equals more stress on the bead in hard turns or landings. By widening the base you theoretically reduce flex on the tire and therefore the bead. That said we are heading into marketing overkill territory. My 24.9 internal works great.

  61. #61
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    Quote Originally Posted by LB412 View Post
    Most of the expansion has to do with the relatively recent tubeless tire trend...By widening the base you theoretically reduce flex on the tire and therefore the bead.
    Thanks for your contribution.

    This gets me thinking (or wildly speculating as some have written). As bholwell noted early on in this thread - he designed DHR2 and the HR2 on a 23mm internal width rim. He also stated that "going from 23mm to 28mm internal isn't much". I'm pretty sure those tires are 2.4 width; they also have Tubeless Ready casing options. Anyway, I'm just reiterating the point that a tire is designed with a specific rim width that is optimal.

    Taking LB412's point: think about a tubeless rim manufacturer (like Stan's for example). They need to get a majority of the TR tires on the market to simply hold air well...even before they start to analyze how tires function in other ways on their rim. Unless a tubeless rim manufacturer are working together for an ideal tubeless wheel (rim+tire), it's not unreasonable to question whether they are building rims outside of the ideal width of most tire casings...simply to get them to hold air better.

    So I have an idea: let's look at one of the newer DH tires (since the OP is about DH tires). Let's try the new 2014 Schwalbe Magic Mary 26 x 2.35. Does anyone know what rim width that tire was designed to work with?

  62. #62
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    By the way, based on information I've gathered online and input on this thread: for my new set of DH wheels I'm considering a DT Swiss FR600 rim (25mm wide) and trying a tubeless ready tire like the 2.35 width Magic Mary. If I had the courage I would go with an EX500 front rim...

    I'm used to running relatively high pressures. I'm 185lbs without gear and I run 28-30psi front and 32-34 psi rear depending on the track. Last two years I used 26mm wide AtomLab Pimp2's with DT Champion spokes, Minion DHF, and an XC Tube (Heavy!!)

  63. #63
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    haven't tried magic mary..

    Muddy Marry was one of my fav fronts, good girth and worked great on a 25mm rim. Wouldn't surprise me if some of those Schwalby were designed w/ 25mm or wider rim in mind, casings are nice size
    video=youtube;][/video]...

  64. #64
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    Like bholwell, tire designer said "the difference in profile going from 23mm to 28mm internal isn't much".

    A wider rim should give more lateral stability at the same air pressure because it is increasing the air-volume in the tire.

  65. #65
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    Quote Originally Posted by oldranger View Post
    Thanks for your contribution.

    This gets me thinking (or wildly speculating as some have written). As bholwell noted early on in this thread - he designed DHR2 and the HR2 on a 23mm internal width rim. He also stated that "going from 23mm to 28mm internal isn't much". I'm pretty sure those tires are 2.4 width; they also have Tubeless Ready casing options. Anyway, I'm just reiterating the point that a tire is designed with a specific rim width that is optimal.

    Taking LB412's point: think about a tubeless rim manufacturer (like Stan's for example). They need to get a majority of the TR tires on the market to simply hold air well...even before they start to analyze how tires function in other ways on their rim. Unless a tubeless rim manufacturer are working together for an ideal tubeless wheel (rim+tire), it's not unreasonable to question whether they are building rims outside of the ideal width of most tire casings...simply to get them to hold air better.

    So I have an idea: let's look at one of the newer DH tires (since the OP is about DH tires). Let's try the new 2014 Schwalbe Magic Mary 26 x 2.35. Does anyone know what rim width that tire was designed to work with?
    The tire/ rim companies HAVE been working together for several years now. The UST rim profile matches together with tire bead profile. Combines with a butyl ( airtight) tire liner and some stiffer sidewalls, the system works well. Some rims need a rim strip as well and the presta valves have a removable core to add sealant. For me, there is no downside to wider rims, unless you include lower tire pressure for better traction a negative.

  66. #66
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    a picture is worth a thousand words

    From Schwalbe's website on their most modern tire designs for the type of riding we are discussing here. Still looks like (by design by Schwalbe) tires are significantly wider than the rims.

    I wonder how wide these rims are?

    Wide Rims?  Don't believe the hype...-schwalbe-section.jpg
    Wide Rims?  Don't believe the hype...-e_img_snake_bite.jpg

    This image is from a section where they describe some design elements of the Super Gravity carcass
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    Super Gravity: Revolutionary carcass technology for MTBs | Schwalbe North America

  67. #67
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    Wide Rims? Don't believe the hype...

    It seems most riders like the wider rims so maybe you should "believe the hype". I do.


    Sent from my iPhone using Tapatalk

  68. #68
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    Quote Originally Posted by MTBMILES View Post
    It seems most riders like the wider rims so maybe you should "believe the hype". I do.


    Sent from my iPhone using Tapatalk
    Yes, I've rode anywhere from 17mm to 30mm internal with roughly the same width tire. I greatly prefer the 30mm internal. I recently switched from 23mm to 30mm internal on the same tire and prefer the 30mm. There is zero hype here, just my real world on the bike experience...YMMV


  69. #69
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    Quote Originally Posted by oldranger View Post
    Yes, I think you missed one: Motocross. I don't have one, but those machines still use tires with a rim width that is narrower than the tire it is supporting. It looks like the margin is greater on the front. But I'm way out of my knowledge 'base' on this MX comparison.

    But you could also add one to your list: BMX Bikes. Those tires seem to be fairly close to the rim width. Wait, let me clarify: those 20" tires that roll on hard pack or paved dry surfaces have tires with a casing width close to the rim width. Hmmm. I wonder when BMXers will go to full suspension 29ers cause they ride faster?

    Your comments where thought provoking - so thanks for that!


    Typcailly a rear rim width for a 250 2 stroke/450 4 stroke is 2.15" (tire is 110mm or 4.33"), front rim is usually 1.6", (tire 80mm or 3.15").
    Tire width makes a pretty big difference on them regarding turn in capabilities, due to the curvature of the tread.
    Having a much narrower front wheel also allows the bike to "drop" into corners beautifully. Something we don't do on the mountain bikes. We run the same tire widths on the mountain bikes, front or rear, sometimes with a wider tire in the front.....

  70. #70
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    Comment from Syntace Website on their W35 rim

    Per Syntace:

    With a rim width (inner) of 28.4 mm the Syntace W35 will provide the RightTireShape for tyres up to 2.5 tyre width.

    Less pressure, more control

    Less tyre pressure means: more grip, less rolling resistance in rough terrain, higher capability to absorb impacts, higher speed in corners as well as better braking traction. Why can a wider rim be ridden with less air pressure? Because the carcass remains upright better and is in contact with the rim via more air volume. On the wide Syntace W35 MX rims, mountain bike tyres mount wider and more directly on the rim with less bulging than on previous conventional narrow rims with low support width. This significantly reduces the tendency of folding when running low air pressures.

    For everything but downhill

    Meanwhile we are able to confirm from several years of experience: Syntace W-Series wheels can do everything. Apart from deliberately caused pinch flats with a Maxxis Minion or Specialized Butcher (or similar). What we mean, is causing harsh pinch flats using a tyre with knob profile which is unfavourable towards wide rims. This will simply dang up the rim hook. And we will have to help out with a crash replacement ;-)


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    Syntace

    So, I guess Syntace would say there is such a thing as a tyre with a knob profile unfavourable towards wide rims. Tires like the Minion or the Butcher.

  71. #71
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    Quote Originally Posted by oldranger View Post
    Per Syntace:

    [I]
    So, I guess Syntace would say there is such a thing as a tyre with a knob profile unfavourable towards wide rims. Tires like the Minion or the Butcher.
    IF you get the area between the knobs to align just right. A rim width that matches any narrower tire/rim combo can produce the same result.

  72. #72
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    With my own designs, and the p35's I ran before, I've noticed the most tire performance improvement in the 2.1 to 2.35 size single-ply tires I've tried with my 650b bike going from narrow 30mm to wider rims.

    By performance improvement, I mean much improved traction and stability, and reduction in rolling resistance on rocky trail. And not to mention a set of my rim's ~300+ gram reduction in measured rim weight compared to p35's, and much stiffer wheels enhancing the feel of traction and stability.

    Bigger tires are certainly improved too, but I think 2.4 and above really need 45mm wide rims for as noticeable a jump in performance gains over the truly hyped so called "wide" 30mm rims available.

    With 2.4 and larger and/or double-ply I think there are diminishing returns in performance improvement with wider rims. Although duel-ply Minion riders on my 29'er x 35mm wide rims "hype" to me and in the forums around the world about their improvement in handling.

    No matter how wide a rim, DH park riders and racers and large huckers need to use pretty high pressures to avoid pinch flats. The wider rim advantage may not be much for DH and FR because of the pressures required. I've also read an interview with a top DH racer who wanted rims that will dent, unlike carbon-fiber rims, when the tire is cased, so they can finish the run without flatting.

    I'm thinking real wide CF rims are more optimum for trail riding, rather than DH, where the much lighter weight is an advantage for climbing and endurance, and for the huge handling advantages at more moderate downhill speeds of public trails of real wide rims stiffening the casing tension under the cornering knobs and running lower pressures.
    www.derbyrims.com STRONGER, STIFFER, LIGHTER

    29 x 35mm wide
    650b x 40mm wide

  73. #73
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    Quote Originally Posted by evasive View Post
    I've never seen anyone claim that wide rims are faster, so I don't see the relevance. The benefit most often cited is the more traction through the use of lower pressures. I doubt any DH racers are willing to risk using lower pressures. On the odd occasion I enter an enduro race, I definitely add pressure to my tires.
    Yeah, I agree. It is not like wider rims are faster, it is that they make the tire wider so the contact area is larger. If anything the grip is better. Will it make a noticeable difference? That is the question for every rider to answer themselves.

    The pros use what company pays them. In the case of all the riders the OP mentioned, all of them are using the widest rims available to them from the company they are sponsored and paid by.

    I think the biggest change to DH racing is gonna be wheel size and that they are gonna start moving to bigger wheels once they strengthen the bigger hoops.

  74. #74
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    Here is a good article on the subject.
    This should answer a lot of questions here.
    I just build a pair of WTB KOM 23mm internal. I 'll figure out soon what it feels like I guess.
    Ride on...

  75. #75
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    Quote Originally Posted by oldranger View Post
    Per Syntace:

    With a rim width (inner) of 28.4 mm the Syntace W35 will provide the RightTireShape for tyres up to 2.5 tyre width.

    Less pressure, more control

    Less tyre pressure means: more grip, less rolling resistance in rough terrain, higher capability to absorb impacts, higher speed in corners as well as better braking traction. Why can a wider rim be ridden with less air pressure? Because the carcass remains upright better and is in contact with the rim via more air volume. On the wide Syntace W35 MX rims, mountain bike tyres mount wider and more directly on the rim with less bulging than on previous conventional narrow rims with low support width. This significantly reduces the tendency of folding when running low air pressures.

    For everything but downhill

    Meanwhile we are able to confirm from several years of experience: Syntace W-Series wheels can do everything. Apart from deliberately caused pinch flats with a Maxxis Minion or Specialized Butcher (or similar). What we mean, is causing harsh pinch flats using a tyre with knob profile which is unfavourable towards wide rims. This will simply dang up the rim hook. And we will have to help out with a crash replacement ;-)


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    Syntace

    So, I guess Syntace would say there is such a thing as a tyre with a knob profile unfavourable towards wide rims. Tires like the Minion or the Butcher.

    This here is fantastic information, it explains two thing at once, tire tech and rim tech.

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    ''you are wrong friend,,,the more we know about products,,and it gives us better choices,thank you,,,,,
    we buy and use the better we ride
    Quote Originally Posted by nvphatty View Post
    we are not all racers or wanna be racers but mere plain recreational riders by in large so much of what you posted does not apply nor will effect the vast majority.

  77. #77
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    I like that a little wider rim is stronger and stays true for a longer period of time. Don't have to get cray cray about it but the old narrow rims weren't as stout. Stan's old Flow ZTR rims is super strong and light. Not sure why they felt the need to put more weight in the newer rims
    "It looks flexy"

  78. #78
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    Quote Originally Posted by manokaiser View Post
    Here is a good article on the subject.
    This should answer a lot of questions here.
    I just build a pair of WTB KOM 23mm internal. I 'll figure out soon what it feels like I guess.
    Ride on...
    I think part of this discussion involves marketing and selling to the masses. First, the pro riders are all sponsored and mostly ride with gear from major companies, few of which make wide rims. Secondly, carbon has become much more common in the bike world, allowing reasonably light wide rims, which previously was not feasible without affordable carbon. Sure, you could make light wide carbon rims but it would be out of most peoples price range. So there wasn't really an opportunity for companies to make a big profit from this.

  79. #79
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    28 is NOT wide, Try a derby 40mm and then make your opinion.....

    I think everyone needs to try a 40mm carbon derby on the front before making opinions to this thread... game changer.... makes a round xc tire an all mtn monster...

    Quote Originally Posted by oldranger View Post
    Hi Folks,
    After researching the subject of rim specs for DH wheels, I find that wider rims are becoming increasing popular. News Flash, right? No, not really, but I have begun to wonder just how much of this is simply hype. Let's be honest and see if there are some facts we can look at before I even give my opinion:

    1) Many of the most popular tires with consistently good reviews (i.e. Maxxis Minion DHF) have casings that were designed before manufacturers were building these 'wide' rims with >25mm internal width.
    2) Many of the top racers use rims with less than 25mm internal width.

    Really? You mean the really fast guys don't ride on wide rims? Why not? I know from personal experience that 'wide' rims feel different, but honestly I don't know if they make me faster. So: I think it is all hype. My guess is that the ideal rim width for DH tires on the market today is 23mm - 25mm of internal width.

    2013 winning riders
    1. Steve Smith Easton Havoc 23mm
    2. Greg Minnaar - Enve DH 21mm (30mm external)
    3. Aaron Gwin DT FR600 24.9mm


    Ive ridden these rims on Freeride, DH Racing and DS:
    1. Crossmax SX 21mm
    2. Atomlab Standard Issue 21mm
    3. Atomlab Pimp2 26mm
    4. Specialized Roval DH 23mm



    Unrelated, but Ive ridden DT Swiss m480 for All Mountain
    DT m480 19.6mm

    My opinion: I notice a different feel when moving from 21mm to 23mm rims (internal width) and I up the psi a bit on the rearbut I don't know if it is actually better traction or just a different feel. My experience is far from a controlled experiment. I don't even really notice the different from 23mm to 26mm.

  80. #80
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    "Trendy wide rims"?
    I've been on D321/EX729 for 10+ years on my DH bikes... Must be the old hawtness thing?!

  81. #81
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    Quote Originally Posted by oldranger View Post
    My opinion: I notice a different feel when moving from 21mm to 23mm rims (internal width) and I up the psi a bit on the rear
    This quote right here shows why you feel a difference, but you're not feeling the advantage of a wider rim. If you move to a wider rim, keeping the tire constant, you are increasing the volume of the tire. Which means you have to LOWER the PSI to compare apples to apples. To make it simple, for the same PSI, increasing volume, makes the tire "harder".

    If you increase tire volume, by increasing inner rim width, you can lower pressure, which will increase your traction - with the added benefit of having a more stable tire with regards to lateral (cornering) forces because of the rounder tire cross section.

    This actually should also decrease rolling resistance, on anything but a smooth surface, because the tire can conform to trail features easily with less energy lost in the tire deformation and rebounding process.

  82. #82
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    If you're a casual rider (or ridgid rider) you might like these ultra wide rims (35mm)and big squishy low pressure tires/Casings, but if your pinning it on any kind of DH, its not the ideal setup. These ultra wide rims are a fred phenomenon, and companies love freds with money. (Flamesuit on lol)
    Last edited by Yody; 03-02-2014 at 01:12 PM.
    friends don't let friends Fred

  83. #83
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    Quote Originally Posted by Bike Whisperer View Post
    I ride a full rigid, what pro DH and FR riders run means jack schitt to me (and most riders).

    My experience with single ply tires is that big volume tires on narrow rims roll when cornering unless I pump them up harder than I prefer. So I like wider rims with big tires that I can run down to ~18psi for traction and some cushion.
    This ^. I like fat tires at lower pressures and I find that with a fat rim they are much more predictable in corners. I think they stick better too. And I'm not talking 25. I like 35. But...that's just me.
    No it never stops hurting, but if you keep at it you can go faster.

  84. #84
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    And rock Stikes while turning, thru rocks, with a wide run unprotected because of a stretched out tire with no sidewall bulge. .. is very dangerous at speed
    friends don't let friends Fred

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    I think that many are not noticing a difference be because they are not going wide enough!
    Ztr Flows ARE my narrow rim.
    The rest of the time I run 47mm as my narrow rim and 80mm as my winter rim. Once on a fatbike, narrow is anything on a normal mtb.
    Now I don't want to turn this into a fatbike vs mtb issue, but my point is. Once tire pressure become as important as it is on a fatbike you learn to try the same on your standard bike. Guess what, I'm hardly trying with guys I used to have to push myself to keep up with.

    For me a narrow Mtb rim is anything less than 25mm inside, I am not fast enough to care about the grams I could save just to loose traction, a better ride, and better handling.

  86. #86
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    Well there is a big difference
    In rim width and performance
    Skinny rims are weeker and flexy and tires are
    Squirmy ! Simple !

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    Quote Originally Posted by DethWshBkr View Post
    Typcailly a rear rim width for a 250 2 stroke/450 4 stroke is 2.15" (tire is 110mm or 4.33"), front rim is usually 1.6", (tire 80mm or 3.15").
    Tire width makes a pretty big difference on them regarding turn in capabilities, due to the curvature of the tread.
    Having a much narrower front wheel also allows the bike to "drop" into corners beautifully. Something we don't do on the mountain bikes. We run the same tire widths on the mountain bikes, front or rear, sometimes with a wider tire in the front.....
    I've always understood the reason for wider rear tires on motorbikes was traction under power. Apparently they actually handle better with narrower tires.
    On a bicycle, which is way underpowered compared to a motorbike, the danger of loosing the front, which is a guaranteed crash, versus the rear in a turn means fatter tires in the front. Part of this is a lot of bikes have much more clearance in the forks than between the chainstays due to drivetrain requirements.

  88. #88
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    Quote Originally Posted by jdubside View Post
    I think everyone needs to try a 40mm carbon derby on the front before making opinions to this thread... game changer.... makes a round xc tire an all mtn monster...
    Totally planned on it but they dont make 26 rims so I went with Velocity Blunt35's.
    I like to fart when I'm in front of you on a climb

  89. #89
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    Quote Originally Posted by oldranger View Post
    i.e. Maxxis Minion DHF
    e.g. is what you wanted; not i.e.

    see more -- Grammar Girl : I.e. Versus E.g. :: Quick and Dirty Tips ?
    Honestly... ahh I give up

  90. #90
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    Personally, I've found wide rims to be stabilizing. Is that good or bad? For me, I like to keep my bikes loose and flickable. This stabilizing action is not desirable. I have to work harder to get my lean on. I also still ride 26" and have flat pedals.

    I can see where the stabilizing action would be a positive trait for someone else though. I also understand that people like to run narrower tires than 2.4". The wide rims seem to be benefit tires in the 2.0-2.2 range more than than 2.4's.

    And I agree with gticlay, the original Flows were hard to beat

  91. #91
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    Last year I was racing enduro in Norway on a not too high level, and I had Syntace W35 rims. They gave super sideways stability, but I had way more pinch flats than before - running tubeless... I had to go for SuperGravity rear for racing and a beefier than before tire for everyday riding. I did the first half of the season om Flow EX, and I hadde no problems on the same tires. When I did the switch, I measured the tires om rims with same tubes and same pressure (digital gauge): the Flow EX gave a 10mm higher and 1mm wider profile on Nobby Nic 2.4"...

    A curiosity is that German Bike mag har a "dream enduro bike" test, where Liteville/Syntace brought a pimped out 301. The where running the narrower, lighter W30 rear with W35 up front in a b6-er config..

    My own conclusion: wide rims good for stability, but not for your tube consumption...

    After the season I sold my W35 wheels and stuck with the Flow EX wheels for harder riding and some Flow sized chinese carbon thingies for everyday riding. Works great for this year I hope.

    I now just wait for the new dual chamber system from Schwalbe, where low pressures and no pinch flats can be a reality..

  92. #92
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    Wide rims (26-30mm internal) were popular in DH & FR from 2000ish to 2007ish. Mavic's top DH rim was 29mm internal and was a mainstay on the circuit. This was when the Minion DHF became the standard tire. Narrow rims for DH became popular when Mavic made the 823 its premier rim and riders starting looking to the NoTubes Flow and similar to reduce weight. A lot of riders were never as happy with the narrower profile but appreciate easy tubeless and having DH wheels you can sprint so the trade off was made. Now that carbon is allowing wide, light rims (and they have tubeless friendly profiles) riders are getting the best of both worlds. It's getting popular on the internet faster than on OEM and World Cup bikes because the companies making these rims are smaller and focus on aftermarket sales. Why Enve continues to cheap out and use the same mold for their DH rim and AM rim (same outside shape but more carbon for thicker walls & narrower width) is beyond me but I bet they come out with a wider 2nd gen DH rim soon now that the market is proven. Oh, and I've heard that the Syndicate uses the AM rim for its greater width & lower weight and just swaps them out when they crack.

    I don't feel like re-reading the OP and proof reading mine to see if I covered his points but here's the conversation ender: Ride a set of 26 to 29mm carbon rims and just try not to prefer them to everything else.
    Ultimate DH wheelset: Light Bicycle DH rims, DT 240 hubs, DT Aerolite spokes. Budget version is NoTubes Flow EX rims, Hope hubs, doubled butted spokes. For burly version substitute Mavic 729 rim.

    Edit: On my DH bike I've exclusively used the Minion DHF 2.7" since like 2004. I've tested other tires but always go back to my standard. Keep in mind that the 2.7" Minion measures the same as the 2.5"s from Spesh, Conti, Bontrager, ect. I've used them on rims from 23-30mm and prefer 26-29mm.
    Keep the Country country.

  93. #93
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    Everyone on this thread should give a 40mm wide carbon rim a try. It is very different. In my opinion much better than easton carbon, enve carbon, and shanghai carbon, all of them I have tried, 19mm wide 28wide, and 30wide... the 40 crushes them all in handling stiffness and durability PERIOD.

  94. #94
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    1980 Araya Catalog

    1980 called and wanted its 32mm wide mountain bike rims back...this is the rim (7x) that was spec'd on the original 1982 Stumpjumper.

    Wide Rims?  Don't believe the hype...-80araya2.jpg

    Wide Rims?  Don't believe the hype...-stump0375rder.jpg

    I think the hype was the skinny roadie width rims starting in the late 80's

  95. #95
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    Re: Wide Rims? Don't believe the hype...

    Quote Originally Posted by Bike Whisperer View Post
    1980 called and wanted its 32mm wide mountain bike rims back...this is the rim (7x) that was spec'd on the original 1982 Stumpjumper.

    Click image for larger version. 

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    Click image for larger version. 

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    I think the hype was the skinny roadie width rims starting in the late 80's
    Exactly.

    This thread went from dumb to really dumb. People going from 21mm to 23mm, keeping the psi the same and saying they can't feel a difference? Really Einstein?

    I have a feeling too many of the contributions here never tried a proper wide rim. As another said, their flows are not even their wide rim. I couldn't agree more.

    Keep running your roadie crap. Enjoy if that's what you like!
    CRAMBA Chairman

  96. #96
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    Thanks for your on-topic perspective Lelandjt.

    Quote Originally Posted by Lelandjt View Post
    Ultimate DH wheelset: Light Bicycle DH rims, DT 240 hubs, DT Aerolite spokes. Budget version is NoTubes Flow EX rims, Hope hubs, doubled butted spokes. For burly version substitute Mavic 729 rim.
    OK - there is opportunity here. I built that exact budget version for my son's Demo 8. Thinking that since he weighs 90 pounds - the lighter spec could hold up for his riding. Next time I'm out riding DH I'll try his ZTR Flow EX/DT Competition wheels on my bike and see how they work. We use Hope hubs on all of our custom wheels.

    Lelandjt - how much riding time do you have on the Light Bicycle DH rims? I am interested in those. I looked at those as I viable option until I decided I didn't believe the hype.

  97. #97
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    Quote Originally Posted by thickfog View Post
    This thread went from dumb to really dumb. People going from 21mm to 23mm, keeping the psi the same and saying they can't feel a difference? Really Einstein?
    This thread has over 16,000 views in 6 days. The only dumb stuff I've seen on this thread are posts from folks trying to change the subject and/or folks that misquote the OP (me). Some of you obviously don't pay attention to details. Which, by the way, is exactly what this thread is about.

  98. #98
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    Checkpoint on the topic - are there carbon DH (Downhill) rim options?

    Are there any major rim manufacturers are making carbon DH rims? I know there have been a lot of good comments regarding the value of wide carbon rims for trail riding and all-mountain-spec bikes, but I'm sticking with the topic of DH.

    There is one reputable manufacturer - Enve that makes a carbon DH rim. Per their website, they designed it for "faster cornering speeds, direct lines, maximum durability, and responsive accelerations". Also according to their website, Enve has been providing this carbon rim for over 4 years, and no other rim manufacturers have followed those footsteps.

    Here are the Enve DH Rim Technical Specs:
    - Hole Counts: 32
    - External Width: 30mm
    - Internal Width: 21mm
    - Depth: 31mm
    - Weight: 475 g
    - Spokes: DT Competition


    ENVE Composites Launches the First All‐Carbon DH Rim - Press Releases - Vital MTB

  99. #99
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    Quote Originally Posted by oldranger View Post
    Are there any major rim manufacturers are making carbon DH rims? I know there have been a lot of good comments regarding the value of wide carbon rims for trail riding and all-mountain-spec bikes, but I'm sticking with the topic of DH.

    There is one reputable manufacturer - Enve that makes a carbon DH rim. Per their website, they designed it for "faster cornering speeds, direct lines, maximum durability, and responsive accelerations". Also according to their website, Enve has been providing this carbon rim for over 4 years, and no other rim manufacturers have followed those footsteps.

    Here are the Enve DH Rim Technical Specs:
    - Hole Counts: 32
    - External Width: 30mm
    - Internal Width: 21mm
    - Depth: 31mm
    - Weight: 475 g
    - Spokes: DT Competition


    ENVE Composites Launches the First All‐Carbon DH Rim - Press Releases - Vital MTB
    Not sure if you consider Light-Bicycle a "major" rim manufactuer, but they have come out with a heavier duty DH version of their 33mm wide carbon rim

    For Downhill version, we add much more carbon fiber to make the rim strong enough. So the weight is heavier than All Mountain version. It is around 460+/-15g.

    Advantages of this newly 33mm wide MTB 26er carbon rim
    *Wider & deeper( 33mm wide and 30mm deep), the strength and stiffness is much improved.
    *Manufactured by our new manufacturing process, making the strength much improved.
    *It is strongly recommended for all rocky mountain bikes like jumping bikes, downhill mountain bikes, all mountain bike.

  100. #100
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    Just a thought;

    This seems, to me, like it will be the same argument as 26" vs 29", but then eventually will come to an agreement that the middle is realistically the best. I haven't rode on real wide rims yet, but I have a feeling that eventually all will agree in the midrange- 23-30mm ish.

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