27.5 x 3.8 VS 29 x 3.0 for dirt use- Mtbr.com
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  1. #1
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    27.5 x 3.8 VS 29 x 3.0 for dirt use

    I have a 2017 Fatboy Expert Carbon which obviously has 26" wheels. When I bought it I only planned to use this bike in the snow so I swapped out the 26x4.0 Ground Control's for Bud/Lou 4.8's (which are awesome in the snow)

    I am interested in a new wheelset for use during the winter when I am in AZ and UT on some primitive roads that are loose and sandy, and probably some 4wd roads here in CO during the summer.

    Initially I planned to purchase a 29x3.0 setup but recently have been reading about 27.5 x 3.8's. From the overall diameter measurements I've been finding it appears that 29x3.0 and 27.5x3.8 should be similar diameter to my 26" Bud and Lou combo. Of course these measurements are from different sources so I'm not sure how accurate they are. Since the OE 4.0's are smaller in diameter than my current Bud/Lou's I can definitely go a little smaller than the Bud/Lou setup if needed.

    Aside from sizing my real question is what makes the most sense for my described riding. It sounds like the 27.5x3.8's roll pretty fast on gravel and dirt although I'm not sure how they compare to 29+. Common sense tells me that 29+ will be faster with less flotation on the soft stuff. I would like to hear from people who have ridden both setups on dirt and get their opinions as to the best all around setup for me. Also I'm not doing any racing with this bike, this is all about fun.

    I should add that I also have a Bluto with 120mm travel.
    Last edited by Projected; 12-09-2018 at 12:58 PM.

  2. #2
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    Quote Originally Posted by Projected View Post
    I am interested in a new wheelset for use during the winter when I am in AZ and UT on some primitive roads that are loose and sandy, and probably some 4wd roads here in CO during the summer.

    Initially I planned to purchase a 29x3.0 setup but recently have been reading about 27.5 x 3.8's. From the overall diameter measurements I've been finding it appears that 29x3.0 and 27.5x3.8 should be similar diameter to my 26" Bud and Lou combo.
    I am a HUGE 27.5x3.8/4 fan. I ride it year round, except for the 15~20 winter rides that necessitate studs.

    post this same question in the plus bike forum, and they will say 29x3 0WNz aLL!

    Quote Originally Posted by Projected View Post
    I would like to hear from people who have ridden both setups on dirt and get there opinions as to the best all around setup for me. Also I'm not doing any racing with this bike, this is all about fun.
    i am all about fun, 100% of the time! well, 99.837%. when i am on the toilet in the morning, i am all business...

    in all seriousness, i had a stache 29x3 tired bike, and i did not get along with it. it did not match my style or the conditions/places i ride, so off she went.

    Quote Originally Posted by Projected View Post
    Common sense tells me that 29+ will be faster with less flotation on the soft stuff.
    tsk tsk my boy, this is the internet, common sense has no place here!

  3. #3
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    29x3.0
    Rigid SS 29er
    SS 29+
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    Full Sus 29er (Yuck)

    Stop asking how much it weighs and just go ride it.

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    I own and ride both. I didn't fall in love with B-fat. Speaking only for myself, they floated only marginally better than 29x3.0, they felt slow and heavy. All that said perhaps it was just the tire I chose, Minion FBF front and rear. This all in bikepacking usage. I know this thread is about B-fat vs 29x3 but for my own curiosity I weighed the rear wheel of both the B-fat and 26x4. B-fat build is Mulefut 50 rims, sapim race spokes, brass nips and the afore mentioned FBF. 26x4 was My Other Brother Darryl rim, sapim race spokes, alloy nips, Husker Du tire. No cassette or rotor on either and B-fat tubeless, 26x4 tubed. Both have Bitex fat 12x197 hubs. Already forgot the actual #'s but the B-fat was 5 oz. (142 grams) heavier.

    Winter has come and all 3 wheelsets now reside on my wall waiting for spring while I ride my Dillinger 5/Wrathchild studdded combo. I'll probably give the B-fat another try in spring.

  5. #5
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    I have both sizes and use both depending on where and what I'm riding( which is New England).
    50mm carbon 27.5 rims with Hodags: gets used on my hard tail more because of the cush factor. Also used when it's wet or soft for traction and float.

    38mm carbon 29 rims with Bontrager Chuapa XR2. Use these more on my F/S bike...and on the hardtail when it's smoother stuff. When it's dry...these things rule.

    Tire choice and rim width make a huge difference.

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    Quote Originally Posted by Rodney View Post
    I am a HUGE 27.5x3.8/4 fan. I ride it year round, except for the 15~20 winter rides that necessitate studs.

    post this same question in the plus bike forum, and they will say 29x3 0WNz aLL!



    i am all about fun, 100% of the time! well, 99.837%. when i am on the toilet in the morning, i am all business...

    in all seriousness, i had a stache 29x3 tired bike, and i did not get along with it. it did not match my style or the conditions/places i ride, so off she went.



    tsk tsk my boy, this is the internet, common sense has no place here!
    What bike do you ride ?

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    Opposed to running your 26" wheels? I run 26 x 3.8 or 4.0 in the summer with good results. On 80 mm rims.

  8. #8
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    29+ all day long.

    B-Fat is a silly marketing gimmick IMHO, but in this specific case, why carry more weight for less roll over and overall diameter, when the conditions don't even require float?
    Cannondale Lefty and HeadShock servicing, wheel building, etc...


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  9. #9
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    Quote Originally Posted by TheNatureBoy View Post
    What bike do you ride ?
    Lenz Fatillac & Surly Wednesday.

    Quote Originally Posted by MendonCycleSmith View Post
    29+ all day long.

    B-Fat is a silly marketing gimmick IMHO, but in this specific case, why carry more weight for less roll over and overall diameter,
    vanhelga 27.5x3.8 is the same OD at 29+. more cush, and currently my favorite 3 season tire. i wish it fit in the back of my fatillac, but it is not even close...

  10. #10
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    Quote Originally Posted by Rodney View Post
    I am a HUGE 27.5x3.8/4 fan. I ride it year round, except for the 15~20 winter rides that necessitate studs.

    post this same question in the plus bike forum, and they will say 29x3 0WNz aLL!



    i am all about fun, 100% of the time! well, 99.837%. when i am on the toilet in the morning, i am all business...

    in all seriousness, i had a stache 29x3 tired bike, and i did not get along with it. it did not match my style or the conditions/places i ride, so off she went.



    tsk tsk my boy, this is the internet, common sense has no place here!
    Haha! Thanks Rodney!

    Quote Originally Posted by DougA View Post
    I own and ride both. I didn't fall in love with B-fat. Speaking only for myself, they floated only marginally better than 29x3.0, they felt slow and heavy. All that said perhaps it was just the tire I chose, Minion FBF front and rear. This all in bikepacking usage. I know this thread is about B-fat vs 29x3 but for my own curiosity I weighed the rear wheel of both the B-fat and 26x4. B-fat build is Mulefut 50 rims, sapim race spokes, brass nips and the afore mentioned FBF. 26x4 was My Other Brother Darryl rim, sapim race spokes, alloy nips, Husker Du tire. No cassette or rotor on either and B-fat tubeless, 26x4 tubed. Both have Bitex fat 12x197 hubs. Already forgot the actual #'s but the B-fat was 5 oz. (142 grams) heavier.

    Winter has come and all 3 wheelsets now reside on my wall waiting for spring while I ride my Dillinger 5/Wrathchild studdded combo. I'll probably give the B-fat another try in spring.
    Great insight, thanks Doug!

    Quote Originally Posted by leeboh View Post
    Opposed to running your 26" wheels? I run 26 x 3.8 or 4.0 in the summer with good results. On 80 mm rims.
    Since I will be riding snow and dirt in the winter, sometimes every other weekend , I don't want to be changing tires that often. Especially if they are set up tubeless.

    So I decided I would rather buy another wheel set for dirt riding and my first thought was 29+. Since I'm buying a new wheel set I figured I should explore the 27.5 option as some people seem to really like it.


    Quote Originally Posted by MendonCycleSmith View Post
    29+ all day long.

    B-Fat is a silly marketing gimmick IMHO, but in this specific case, why carry more weight for less roll over and overall diameter, when the conditions don't even require float?
    I guess the main reason for looking at the 27.5 is that I "might" want to try riding down some washes, and a specifically a trail behind my parents house in AZ that crosses a few washes. But honestly the 29+ will probably float good enough for the percentage of time I see myself in any real sand. It may not be worth carrying around the weight of the 3.8's everywhere for the once in a while they may help out.

    That is why I wanted to get some opinions on how slow/fast/heavy the 3.8's feel compared to the 29+. Again common sense tells me they don't really compare, but just seeing what people think.

    Quote Originally Posted by the mayor View Post
    I have both sizes and use both depending on where and what I'm riding( which is New England).
    50mm carbon 27.5 rims with Hodags: gets used on my hard tail more because of the cush factor. Also used when it's wet or soft for traction and float.

    38mm carbon 29 rims with Bontrager Chuapa XR2. Use these more on my F/S bike...and on the hardtail when it's smoother stuff. When it's dry...these things rule.

    Tire choice and rim width make a huge difference.
    The 27.5 cush is something to consider on my hard tail. Even though I started on full rigid bikes when I was 14 and rode hard tails with 80mm of travel for many years my summer bike is a 155/160mm Transition Patrol so there may be some adjustment on my end

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    29+ is the obvious answer as numerous posters have attested to.

    27.5x3.8 would be a complete waste of money. If you want a 4" tire, there are a gazillion 4" tires that fit on the wheels you already have. For summer use, the Jumbo Jim 26x4 tire is very popular.

    I second the above poster who said that "B-fat" is complete marketing nonsense. If you want a fat bike, ride a fat bike. If you want something with a little more grip that rides like a more conventional mountain bike, then ride a plus bike. "B-fat" is neither.

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    Quote Originally Posted by twodownzero View Post
    29+ is the obvious answer as numerous posters have attested to.

    27.5x3.8 would be a complete waste of money. If you want a 4" tire, there are a gazillion 4" tires that fit on the wheels you already have. For summer use, the Jumbo Jim 26x4 tire is very popular.

    I second the above poster who said that "B-fat" is complete marketing nonsense. If you want a fat bike, ride a fat bike. If you want something with a little more grip that rides like a more conventional mountain bike, then ride a plus bike. "B-fat" is neither.
    As I stated above I do not want to change tubeless tires once or twice a month so a 2nd wheel is what I'm looking at. As a result I'm not considering 4.0 tires on my current 26" wheels.

    I also had thoughts of possibly needing more float than 29+ so I thought, considering contact patch size, 27.5x3.8 might roll better and float about the same as a 26x4.0.

    Most likely I'll end up on 29+ but worth getting some opinions since I'm starting from scratch for wheel choice.

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    A taller fat wheel and tire combo is just heavier. The knobs on fat bike tires are not as big as the knobs on regular mountain bike or plus tires, and so the available traction on loose surfaces isn't that different. I actually think my 27.5x2.8" plus tires have more grip when leaned than my 26x4.8" fat bike tires on gravely loose over hard (higher ground pressure, larger knobs). In sand, it's no contest; any fat bike tire is going to have much more flotation than a plus tire. On the flat and flowy, once the heavy wheelset is going, it doesn't make much difference. Speeding up and slowing down is where the fat bike tires me out. Making the rim and tire combo taller and heavier for the same width tire is just going to make that situation worse. That's why a 27.5 fat makes no sense. It doesn't do anything 26 fat wasn't already doing, it just requires you to speed up and slow down a greater mass.

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    Quote Originally Posted by twodownzero View Post
    A taller fat wheel and tire combo is just heavier. The knobs on fat bike tires are not as big as the knobs on regular mountain bike or plus tires, and so the available traction on loose surfaces isn't that different. I actually think my 27.5x2.8" plus tires have more grip when leaned than my 26x4.8" fat bike tires on gravely loose over hard (higher ground pressure, larger knobs). In sand, it's no contest; any fat bike tire is going to have much more flotation than a plus tire. On the flat and flowy, once the heavy wheelset is going, it doesn't make much difference. Speeding up and slowing down is where the fat bike tires me out. Making the rim and tire combo taller and heavier for the same width tire is just going to make that situation worse. That's why a 27.5 fat makes no sense. It doesn't do anything 26 fat wasn't already doing, it just requires you to speed up and slow down a greater mass.
    Makes sense.

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    If you can only have one wheelset, make it 27.5 x fat.

    If you're going to keep your 26" set and add another set, 29+ makes the most sense. Fast, efficient, and fun -- a perfect counterpoint to your 26" x slow wheelset.

  17. #17
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    i own and ride both on a surly ICT. I find the 27.5x3.8 is great for flowing trails without a lot of rocks. When things get super rocky I like being able to fit my tire in tight spots without rubbing my sidewalls up, and I like a slightly higher bb, so I go with the 29+. Most of my riding is in relentlessly rocky areas so the 29+ stay on and the 27.5x3.8 set up sees very little use. I like to use the 27.5+ set up as a studded winter wheelset but I haven't found the money and there doesn't seem to be a good way to stud the hodags that I have.

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    Quote Originally Posted by twodownzero View Post
    29+ is the obvious answer as numerous posters have attested to.

    27.5x3.8 would be a complete waste of money...

    I second the above poster who said that "B-fat" is complete marketing nonsense. If you want a fat bike, ride a fat bike. If you want something with a little more grip that rides like a more conventional mountain bike, then ride a plus bike. "B-fat" is neither.
    spoken like a true hater...



    Quote Originally Posted by mikesee View Post
    If you can only have one wheelset, make it 27.5 x fat.

    If you're going to keep your 26" set and add another set, 29+ makes the most sense. Fast, efficient, and fun -- a perfect counterpoint to your 26" x slow wheelset.
    excellent advice. / thread

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    Quote Originally Posted by twodownzero View Post
    The knobs on fat bike tires are not as big as the knobs on regular mountain bike or plus tires.
    Sorry, that is just patently false. Name me a non-fat tire with knobs as big as a Wrathchild, Vanhelga or Wazia (I'll stop there)?

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    Quote Originally Posted by BlueCheesehead View Post
    Sorry, that is just patently false. Name me a non-fat tire with knobs as big as a Wrathchild, Vanhelga or Wazia (I'll stop there)?
    Nate, Bud, Lou, Flowbeist, Dunderbeist
    Rigid SS 29er
    SS 29+
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    Stop asking how much it weighs and just go ride it.

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    Quote Originally Posted by *OneSpeed* View Post
    Nate, Bud, Lou, Flowbeist, Dunderbeist
    Now that's just spiking the ball.

    Heck, the popular XR2/Chupa knobs are not as big as a Knard.
    Last edited by BlueCheesehead; 12-10-2018 at 09:39 AM.

  22. #22
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    Quote Originally Posted by mikesee View Post
    If you can only have one wheelset, make it 27.5 x fat.

    If you're going to keep your 26" set and add another set, 29+ makes the most sense. Fast, efficient, and fun -- a perfect counterpoint to your 26" x slow wheelset.
    I think Mike makes the most sense. For what it's worth, I have 26 & 27.5. I really like 27.5 and only put on the 26 to wear thru my tire stock and get a touch extra float in the soft stuff. 27.5 is faster and more nimble for me - but they are close enough that trying something totally difference (a la 29+) is a better spread. Can't help you on the 29+ specifically but the people I see rocking them seem to do pretty good blasting head on thru the chunk.
    Working to stomp out redundancy, I repeat, working to stomp out redundancy.

  23. #23
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    27.5 x 3.8 VS 29 x 3.0 for dirt use

    We had these discussions when the 29er came out. It was heavier, slower, gimmick, fad, bla, bla. Same arguments with the 27.5 format.

    Anyway, my advice for dirt only, is to get the 27.5 3.8 format only if you insist on seeing a fat tire under you.


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    I got one of the last steel Chumba Fat bikes and had it built up 27.5 X 3.8 with 80mm rims. Loads of fun, carves real nice and I'm no slower/faster because of the size.. I have had probably every size wheel over the years and as mikesee mentioned this is my only wheel set for this bike. Great guys at Chumba to deal with BTW.

  25. #25
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    IMO I'd go 29+

    Simply because, as others have stated, there isn't as dramatic of a difference between 26 4.0 and 27.5 3.8

    The extra roll-over is what I'd be looking forward to. I run 29 X 3.0 on a fat bike and it's excellent for what it's intended for.

  26. #26
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    Missing from this conversation is the rims that go with your tires.

    If you have 27.5 x 3.8 with 80mm rims, you still have a fat bike. A bike which can handle sand or snow.

    For dirt, I run 27.5 x 3.8 with 50mm rims. The weight difference is tiny compared to 29+ and I would love to see some real data showing they roll slower than 29+. Tire choice is always a bigger factor than width anyway. In fact I might be willing to place a bet my 27.5 hodags are faster than 29+ with minions on gravel/hardpack. I do know that every time I've gone out with guys on standard bikes (27.5 or 29) I roll faster than they do when coasting on gravel or hardpack. They might have the weight advantage, but the roll over of the big diameter rubber is a real thing.

    In any case, I ride where most buddies are on full suspension, so I liked the idea of the extra volume and lower pressures front and back to soften the ride.

    So back to your original post, I'd say you can't go wrong with either choice, especially if you use light and narrower rims with the 27.5 option.
    Last edited by Teton29er; 12-11-2018 at 10:17 AM.

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    Quote Originally Posted by BlueCheesehead View Post
    Now that's just spiking the ball.

    Heck, the popular XR2/Chupa knobs are not as big as a Knard.
    I have an Ice Cream Truck and a Karate Monkey. I could take the depth gauge out and measure, but I don't think that Bud/Lou have lugs as deep as even the Dirt Wizards that came on my KM? Perhaps it's just perception from riding both plus and fat? I love fat, but mostly for being able to monster over everything, not so much for the (mostly cornering) traction on the loose over hard/dry desert we have here. I know everyone's trails are different and perhaps in dirt, the extra width overcomes the reduced ground pressure when cornering. I don't ride that close to the friction limit on purpose and trials change day by day, so it's really hard to say. I would agree that more XC rated tires have smaller knobs; I don't own an XC bike or XCish tires, though.

    There certainly are some chunkier fat tires out there. I really had Bud/Lou or the Jumbo Jim in mind when I made that post, since that's what everyone runs here.

  28. #28
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    Quote Originally Posted by twodownzero View Post
    ... I don't think ...


    Quote Originally Posted by twodownzero View Post
    I really had Bud/Lou or the Jumbo Jim in mind when I made that post, since that's what everyone runs here.
    i don't run bud/lou or JJ, nor does anyone around me. I take that back, two guys with wozos ran the stock JJ for a short time, but after flatting on every ride, they learned fast...

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    Quote Originally Posted by twodownzero View Post
    I would agree that more XC rated tires have smaller knobs; I don't own an XC bike or XCish tires, though.

    There certainly are some chunkier fat tires out there. I really had Bud/Lou or the Jumbo Jim in mind when I made that post, since that's what everyone runs here.
    One certainly can find SOME regular or plus tires with larger knobs than SOME fat bike tires, but the original statement was a blanket statement. The blanket nature of the statement is what I took exception to.

    Certainly the goal, which is appropriate traction, is condition and use dependent. In some conditions narrower tires can provide more traction.

    (For the record, I do not run Bud/Lou or JJ either...but then again I do not run super aggressive plus tires either)

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    Quote Originally Posted by Teton29er View Post
    Missing from this conversation is the rims that go with your tires.

    If you have 27.5 x 3.8 with 80mm rims, you still have a fat bike. A bike which can handle sand or snow.

    For dirt, I run 27.5 x 3.8 with 50mm rims. The weight difference is tiny compared to 29+ and I would love to see some real data showing they roll slower than 29+. Tire choice is always a bigger factor than width anyway. In fact I might be willing to place a bet my 27.5 hodags are faster than 29+ with minions on gravel/hardpack. I do know that every time I've gone out with guys on standard bikes (27.5 or 29) I roll faster than they do when coasting on gravel or hardpack. They might have the weight advantage, but the roll over of the big diameter rubber is a real thing.

    In any case, I ride where most buddies are on full suspension, so I liked the idea of the extra volume and lower pressures front and back to soften the ride.

    So back to your original post, I'd say you can't go wrong with either choice, especially if you use light and narrower rims with the 27.5 option.
    Nope, weight is more important. Rolling resistance is highly dependent on the knob arrangement, but a 3.8 tire will be considerably heavier than a similarly knobbed 3.0 tire. And it will roll the same or slower.


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    Quote Originally Posted by serious View Post
    Nope, weight is more important. Rolling resistance is highly dependent on the knob arrangement, but a 3.8 tire will be considerably heavier than a similarly knobbed 3.0 tire. And it will roll the same or slower.


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    Excellent point. I looked up the numbers, and i could save a whole pound on my bike with 29+. That means my 23 pound single speed with 27.5 hodags could weigh in at 22 pounds. So instead of me and bike weighing 208 pounds, it would be 207 pounds.

    Well that changes everything. No wonder I'm so slow!

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    Quote Originally Posted by Teton29er View Post
    Excellent point. I looked up the numbers, and i could save a whole pound on my bike with 29+. That means my 23 pound single speed with 27.5 hodags could weigh in at 22 pounds. So instead of me and bike weighing 208 pounds, it would be 207 pounds.

    Well that changes everything. No wonder I'm so slow!
    1/2 lbs per tire is huge! But if you are slow, that wonít matter. 😉
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    I have found my bike to be about 2# lighter with 29+ vs 26 x 4.

    FWIW, overall diameter of 29+ and 27.5 x 3.8 is about the same.

    My gps data shows the 29+ to be faster on the same trails.

    29+ and 26 fat essentially gives you 2 different bikes with the same frame.

  34. #34
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    Interesting thread. Having just put 400 miles on my new build Fatboy C with 26 4.8 JJ I started considering another wheelset for the summer time. What rim width would be recommended for a 29x3.0 tire?

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    Quote Originally Posted by kk2 View Post
    Interesting thread. Having just put 400 miles on my new build Fatboy C with 26 4.8 JJ I started considering another wheelset for the summer time. What rim width would be recommended for a 29x3.0 tire?
    Some go as narrow as 30mm. Others as wide as 50mm. About halfway between feels like the sweet spot, but it's dependent on your specifics.

  36. #36
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    Quote Originally Posted by serious View Post
    Nope, weight is more important. Rolling resistance is highly dependent on the knob arrangement, but a 3.8 tire will be considerably heavier than a similarly knobbed 3.0 tire. And it will roll the same or slower.


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  37. #37
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    Quote Originally Posted by Lars_D View Post
    Actually, rolling resistance is a function of rubber compound, sidewall thickness, and pressure. Knobb arrangement makes almost no difference.
    Well yes, all those things affect rolling resistance, but how on earth have you reached the conclusion that knob arrangement makes almost no difference?
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  38. #38
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    Quote Originally Posted by Lars_D View Post
    Actually, rolling resistance is a function of rubber compound, sidewall thickness, and pressure. Knobb arrangement makes almost no difference.
    Sorry Lars, anyone that has ridden a Nate and a Knard (same manufacturer, same casing) knows that tread design makes a huge difference in rolling resistance.

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    I kind of have the same idea / question as OP. I have 26"x4.8" and was wondering if 29+ would be good for the 3 seasons.

    OP has a suspension fork and I assume you answers took that into account. I don't and don't plan to. Would for a rigid fork a 29+ still be better in summer? My fear is it would give me less dampening over roots etc. (a wheelset will cost me close to $500, so hard to just try out :-).
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  40. #40
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    Quote Originally Posted by HerrKaLeun View Post
    I kind of have the same idea / question as OP. I have 26"x4.8" and was wondering if 29+ would be good for the 3 seasons.

    OP has a suspension fork and I assume you answers took that into account. I don't and don't plan to. Would for a rigid fork a 29+ still be better in summer? My fear is it would give me less dampening over roots etc. (a wheelset will cost me close to $500, so hard to just try out :-).
    A Krampus is $1500 and opens up options. You're going to spend $750 on wheels and tires, plus a brake rotor and a cassette. You're halfway to having a second bike!

  41. #41
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    Quote Originally Posted by twodownzero View Post
    A Krampus is $1500 and opens up options. You're going to spend $750 on wheels and tires, plus a brake rotor and a cassette. You're halfway to having a second bike!
    Yes, a Krampus is $1500, but with a wheelset thatís worth maybe $250.

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    Quote Originally Posted by mikesee View Post
    Yes, a Krampus is $1500, but with a wheelset thatís worth maybe $250.
    How is that any different than any other $1500 bike? It's got WTB i40 hoops, so the rims aren't bad. Like all Surly products it's meant to be durable, versatile, and a good value, not high end or fancy.

    I'm not sure I understand the comment, what more do you expect at that price point? There are plenty of carbon FS bikes that cost $4k and have equally crappy wheels.
    Rigid SS 29er
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    Stop asking how much it weighs and just go ride it.

  43. #43
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    Quote Originally Posted by mikesee View Post
    Yes, a Krampus is $1500, but with a wheelset thatís worth maybe $250.
    If you really don't think the wheelset on a Krampus is decent enough to get a whole lot of enjoyment out of, I don't think 29 plus is for you. If you want to race or something, you should be on something else. Plus bikes are for fun (and they ARE fun).

    I don't have a Krampus but my best friend does, and I cannot even type into this box how much fun we have had on our plus bikes this year. I have a fat bike, too, and as much as I love fat, the plus bikes are just too much fun. Do yourself a favor and stop worrying about trivial details and give in and get yourself a Krampus. For the right size rider, there is nothing better.

  44. #44
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    Quote Originally Posted by twodownzero View Post
    If you really don't think the wheelset on a Krampus is decent enough to get a whole lot of enjoyment out of, I don't think 29 plus is for you. If you want to race or something, you should be on something else. Plus bikes are for fun (and they ARE fun). .
    I ride 29+ full time and have for a few years. Iím well aware of what they bring to the table and frequently steer appropriate candidates toward it.

    My point was simply one of equivalence, or a lack thereof. A $250 wheelset isnít remotely equivalent to one that costs 3x as much. If you donít understand that basic fact there really isnít any common ground from which we might discuss.

  45. #45
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    This is a good example of 35mm width summer wheels. For either 29Ē Or 27.5Ē the tires would be 2.8Ē to 3.2Ē

    https://shop.fatbackbikes.com/fatbac...wheel-set.html

    Quote Originally Posted by kk2 View Post
    Interesting thread. Having just put 400 miles on my new build Fatboy C with 26 4.8 JJ I started considering another wheelset for the summer time. What rim width would be recommended for a 29x3.0 tire?

  46. #46
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    Quote Originally Posted by MendonCycleSmith View Post
    29+ all day long.

    B-Fat is a silly marketing gimmick IMHO, but in this specific case, why carry more weight for less roll over and overall diameter, when the conditions don't even require float?
    For flow trails, you're probably right. But for northeast gnar & drops, B-Fat is the sweet spot.

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    I own a Rocky Suzi-Q with the stock 27.5X3.8 setup as well as a 50mm 29er setup and have run Minion 3.0 as well as the Chupa/XR2 so can comment based on vast experience.

    Snow/Soft - No question the b/3.8 offers more float and is far better as a soft conditions setup. Aslo, they roll far faster than 26X4.0 with a similar footprint. The format is far more than just marketing hype. I would say roughly 25-40% more

    Speed/hardpack - 29X3.0. Not even close

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    If I had to keep only one for the riding I do - 27.5x3.8 on 50mm rims is my pick. Overall, for me itís more capable and more fun to ride. Absolutely not a waste of money and not a marketing hoax. Gnarwhal front, hodag rear is absolutely marvelous for all sort of trail riding in all kind of conditions. 29x3.0 is more efficient in terms of speed, I like it too. But my heart is with 27.5x3.8. I wish there would a bigger list of FS bikes that can takes such tires...

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    Quote Originally Posted by burtronix View Post
    For flow trails, you're probably right. But for northeast gnar & drops, B-Fat is the sweet spot.
    OP wasn't asking about B+. I ride the shit out of my 29+ hardtail on technical Northeast trails. Please do come visit some time and try to keep up.

    Quote Originally Posted by survivalofthefattest View Post

    Snow/Soft - No question the b/3.8 offers more float and is far better as a soft conditions setup. Aslo, they roll far faster than 26X4.0 with a similar footprint. The format is far more than just marketing hype. I would say roughly 25-40% more

    Speed/hardpack - 29X3.0. Not even close
    OP wasn't asking about snowy conditions since he clearly stated the already had a 26" snow wheelset.
    Rigid SS 29er
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    Stop asking how much it weighs and just go ride it.

  50. #50
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    I didn't see any numbers here for actual overall diameter of tires. The OD of a 29x3 is quite a bit taller than a 26x4.

    Can someone give me an actual OD of 27.5x3.8 Maxxis Minion, at say 12psi?

    If I built some up I'd probably go with a 50mm rim, but from my measurements over the years rim width doesn't affect OD by much at all. Maybe if comparing a sub 30mm to a plus 100mm you'd get more, but anywhere in the same ballpark is going to be about the same OD.
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  51. #51
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    Quote Originally Posted by modifier View Post
    I didn't see any numbers here for actual overall diameter of tires. The OD of a 29x3 is quite a bit taller than a 26x4.

    Can someone give me an actual OD of 27.5x3.8 Maxxis Minion, at say 12psi?

    If I built some up I'd probably go with a 50mm rim, but from my measurements over the years rim width doesn't affect OD by much at all. Maybe if comparing a sub 30mm to a plus 100mm you'd get more, but anywhere in the same ballpark is going to be about the same OD.
    745-750mm (29.3-29.5") on 50mm rim.
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    Owning and riding both diameter 3.8 Hodags on a pair of Farleys, I can't say it's marketing hype. Especially for non-winter riding. The 27.5 x 3.8 Hodags over the 26r have a more trim profile and don't leave me feeling too bouncy.

    Also owning modern era wide 29r rims (29 mm inner) with modern big but not plus tires currently on a modestly priced Honzo I can't imagine wanting the others for general trail riding.

    It all works. I've also used and rented plus size and bigger fatties. Thing is, the big 29r wheels have some got your back and confidence but leave you with a bike that feels far more fun, speedy, more responsive to pump, and just overall feeling great.

    It will all work. We've got a pair of parents and pair of twins same height sharing same fleet of bikes. They'll all work if you want a trail ride but those wide (not plus) 29r wheels are versatility and fun at same time. They do duty as a gravel bike, short distance commuter, they send it on a jump line, and work for an hours or many miles ride.

    If anything's left me thinking hype or hit the peak it would be 27.5 Plus against 29rs.
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  53. #53
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    Quote Originally Posted by modifier View Post
    Can someone give me an actual OD of 27.5x3.8 Maxxis Minion, at say 12psi?
    Quote Originally Posted by nitrousjunky View Post
    745-750mm (29.3-29.5") on 50mm rim.
    nitrousjunky is correct. I have had every one of the 27.5x3.8/4 tires. They are all in the 29.5" OD range except for the 45nrth tires, Vanhelga and Dilly4. Those two are almost an inch taller, measuring ~30.25". Every one of the 27.5x3.8/4 tires are the SAME width.

    I cannot fit the 27.5 VH/D4 in the back of my existing fatillac. I love the VH so much, I had my new fatillac built to accept it.
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  54. #54
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    Quote Originally Posted by Rodney View Post
    Every one of the 27.5x3.8/4 tires are the SAME width.
    How wide exactly and on what rim?

  55. #55
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    Quote Originally Posted by rruff View Post
    How wide exactly and on what rim?
    i measured all the 27.5x3.8/4" tires on mulefut & scraper 50 (~3.6x"), mulefut & nextie 65 (~3.7x"), and mulefut 80 (~3.8x"). barring no wacky production tolerances, all of them are the same width on the same rim. the only variance is the current 27.5x3.8/4" 45nrth tires, which are ~3/4" taller then the other mnfr's. But, again, they are the same width.

    I now have Rhyolite 70's, but i didn't bother measuring anything because i am sure it is marginally wider than the old 65's i had.

    over the years i have posted the measurement pics and info on what seems like a 100 different threads. I think most of my findings are on the BFat thread.
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  56. #56
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    Quote Originally Posted by Rodney View Post
    i measured all the 27.5x3.8/4" tires on mulefut & scraper 50 (~3.6x"), mulefut & nextie 65 (~3.7x"), and mulefut 80 (~3.8x"). barring no wacky production tolerances, all of them are the same width on the same rim. the only variance is the current 27.5x3.8/4" 45nrth tires, which are ~3/4" taller then the other mnfr's. But, again, they are the same width.
    Thanks! Sorry to make you repeat yourself, but I'm new to this and have a lot of catching up to do.

    Do those tires work well on 50mm rims, vs 70mm?

    I'm interested in getting a pair of rigid bikes that are just wide enough for 4" tires, for general dirt riding and occasional sand washes and beach. The RSD Sergeant is near perfect, but the 83mm BB makes the Q factor much wider than necessary. I might have to go custom so I'm looking at more precise tire dimensions. A 150mm rear spacing and 73mm BB (with the ring flipped close to the crankarm) seems like it would be perfect but I don't see any bikes with that spec for sale.

    I also thought it might barely be possible for a 29+ with normal boost 140mm spacing to fit a 27.5x4.0 on a 50mm rim, but I can't find mention of anyone trying it.

  57. #57
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    Quote Originally Posted by Rodney View Post
    i measured all the 27.5x3.8/4" tires on mulefut & scraper 50 (~3.6x"), mulefut & nextie 65 (~3.7x"), and mulefut 80 (~3.8x").
    ...
    I now have Rhyolite 70's, but i didn't bother measuring anything because i am sure it is marginally wider than the old 65's i had.
    I would like to second rruff's question, given you are now on 70mm rims, would you say that 65/70mm is the rim width you would choose over a 50mm as your only rim option for a three season 3.8" tire?
    Looking for fairly priced 17.5" Farley EX 8/9.8 in Germany or neighbouring countries. Frame only or whole bike, TIA!

  58. #58
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    I'd go with 65/70mm if you have the room. I'm just wanting to make the tire as narrow as possible.

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    Quote Originally Posted by bitflogger View Post
    The 27.5 x 3.8 Hodags over the 26r have a more trim profile and don't leave me feeling too bouncy.

    Also owning modern era wide 29r rims (29 mm inner) with modern big but not plus tires currently on a modestly priced Honzo I can't imagine wanting the others for general trail riding.
    I'm guessing that isn't with a rigid fork? Would your preference tilt in favor of a 3.8 if it was?

  60. #60
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    Quote Originally Posted by El_Topo View Post
    I would like to second rruff's question, given you are now on 70mm rims, would you say that 65/70mm is the rim width you would choose over a 50mm as your only rim option for a three season 3.8" tire?
    I run 50's year round w/ 27.5x4, but only in fair weather. I run the 70's w/ 27.5x4 year round when it is sloppy/wet/light snow.

    next wheelset on the agenda is another 29xi40 and bontrager se4. but, it will no get much use as i will only use it for the "fast" trails, and i typically ride slower techy stuff.

    fyi, to complete my wheel combo, in snow/snow & ice, i run 26x4.6 Wrathchilds on 90's.
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  61. #61
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    Have a similar setup as you. Winter 26' 80mm rims 4.6 studded Wrathies. Summer has been 27.5 65mm wheels with an assortment of tires. My fatty is rigid so been trying to balance some cush with the attributes of rollover. I love the Hodag for singletrack, all of which is not smooth, rocks, roots, but I also don't use it for gnarly stuff. For gravel I prefer using 4.5 Barbies and really like them, but what a handful on tight twisty stuff. Changing tubeless isn't fun, so I end up leaving one set on for stuff and accepting it's downfalls, then changing and doing the same.

    So this summer finally committing to 29+ and that will be for gravel, bikepacking, smoother stuff. 27.5 will just get the Hodags for trails and barbies will be in reserve for the occasional exploring unknown destinations.

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    Should add, was given a set of 27.5x3.0 Teravail Coronado light and supple mmmm that I never really gave a chance because my rims are 65mm. Finally threw them on last fall just to say I tried them. I was surprised at the round profile and the sidewalls that felt like a lambskin condom were well beyond the rims, probably 1/4-3/8" beyond. They rolled very well on gravel, soaked up things nicely. Then I tried them on singletrack and didn't care for them, but they aren't really meant for that from what I can tell. Bit of a one trick pony, however, if 27.5++ is your thing, and smooth or gravel is in the cards, they would be an option that is overlooked I think. They seem to be between bfat and 27+.

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