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  1. #1
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    29+ Tire Geometries

    I'm attempting to collect the Tire Geometries for all currently available 29+ tires in one place. One metric which is vs helpful especially when trying to find a suspension fork is Overall Diameter, similar to what Surly publishes in their Surly Tire Geometries doc. Here's what I have collected from Surly and the forums:


    Tire tpi Weight g Bead to Bead mm
    Surly Knard 29 x 3 120 975 188
    Surly Knard 29 x 3 27 1217 188
    Surly Dirt Wizard 29+ 120 1004 170
    Bontrager Chupacabra 120 875 187
    Maxxis Chronicle 120 1069 188
    Maxxis Chronicle 60 1040
    Panaracer Fat B Nimble 120 765 178
    Vee Fatty Trax 120 873 188
    Innova Gravity Vidar 935 180
    Vittoria Bomboloni 120 960 172




    Tire Rim Width mm Overall Diameter mm Knob Shoulder Width mm Max Casing Width mm
    Surly Knard 29+ 50 768 80 75
    Surly Dirt Wizard 29+ 50 756 73 69
    Bontrager Chupacabra 35 768 77 73
    Bontrager Chupacabra 50 77
    Maxxis Chronicle 50 76
    Maxxis Chronicle 35 75 71
    Panaracer Fat B Nimble 35 763 69 67
    Vee Fatty Trax 50 768 74 65
    Innova Gravity Vidar 35 768 74 71
    Innova Gravity Vidar 50 772 78
    Vittoria Bomboloni 50 757 76
    Last edited by mbanzi; 10-14-2015 at 03:44 PM.

  2. #2
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    Updated a few tires. Anyone have the overall diameters I'm missing from the table?

  3. #3
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    From the Fat-bike.com website: Weight (of the Bomboloni) is a respectable 955 g/964 g, which is lighter than both the Knard and Maxxis Chronicle but heavier than the Chupacabra. Bead to bead measurement on the Bomboloni comes in at 172 mm (measured with the tire laid flat), which is approximately 10 mm narrower than the Knard, Chronicle, and Chupacabra. This results in the Bomboloni being slightly shorter than the aforementioned tires but not by much. Outside knob to knob measurement was 76 mm with the tire mounted tubeless at 15 psi on a Rabbit Hole. For reference, the Knard is 80 mm, Chupacabra 77 mm, and Chronicle 76 mm so the Bomboloni is about the same width (outside knob to outside knob) as other existing 29+ offerings.

    And from Bikeny's post in the 29+ tire thread:
    I just received my pair of Panaracer Fat B Nimble 29+ tires. I only weighed/measured one, but the other should be pretty close. Weight is indeed very light, 749g! The bead to bead measurement when laid out flat is 174mm. For comparison, I measured a Vee Trax Fatty 29+ at 851g and 184mm B-B, so the Panaracer is smaller. I have not mounted them yet so don't know how much smaller yet.

    Also for reference from Fat-Bike.com:

    Bontrager Chupacabra: 895g/884g B-B: 184mm
    Vittoria Bomboloni: 955g/964g B-B: 172mm
    Maxxis Chronicle 120tpi EXO: 1076g/1062g B-B: 188mm

    Also, Gravity Vidar on a 50mm rim is about 772mm in diameter.

    DW on a 50mm rim is 75mm wide at knobs after casing has stretched.

  4. #4
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    Good idea, but it all really depends on what width rim you run them on, or at least that's what I've found. When I mocked up my Banshee Phantom with Chronicle in the rear on i25 rim, it fit into the frame with a tiny bit of room to spare in the slack setting, recently I tried it again with a Dually45 and the wheel would not even budge it had grown so much because of the 14mm internally wider rim - mainly height.
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  5. #5
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    Quote Originally Posted by LyNx View Post
    ...it had grown so much because of the 14mm internally wider rim - mainly height.
    Rim width has virtually no effect on tire height. 14mm of rim width would affect casing width by 4-5mm.

  6. #6
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    Yeah, whatever, that must be it, must be fvcking imagining that it wouldn't spin on the 39mm ID rim, but spun just fine on the 25 ID rim Wish you "genius" engineers would just stay in your labs with your "theorectical thinking" and let us real folks get on with life where we actually use and try stuff FOR REAL

    Quote Originally Posted by craigsj View Post
    Rim width has virtually no effect on tire height. 14mm of rim width would affect casing width by 4-5mm.
    One day your life will flash before your eyes, will it be worth watching??

  7. #7
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    One thing to be aware of is 29+ tires are going to grow a bit with some use. So if you test fit a tire new and then test fit it again after a few weeks use you'll find it's not got the same clearance.

    I've found this to be true of all the Surly tires I've either had my hand on or that are on friends' bikes. There are also enough reports of the same thing on MTBR to assume other brands will do the same thing.

    It's no big deal if you have a ton of clearance, but if your setup barely works with a new 29+ tire it's likely that you'll lose enough clearance for it to be an issue as the tire gets used.
    Safe riding,

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  8. #8
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    Quote Originally Posted by vikb View Post
    One thing to be aware of is 29+ tires are going to grow a bit with some use. So if you test fit a tire new and then test fit it again after a few weeks use you'll find it's not got the same clearance.

    I've found this to be true of all the Surly tires I've either had my hand on or that are on friends' bikes. There are also enough reports of the same thing on MTBR to assume other brands will do the same thing.

    It's no big deal if you have a ton of clearance, but if your setup barely works with a new 29+ tire it's likely that you'll lose enough clearance for it to be an issue as the tire gets used.
    Exactly! I was going to post this same comment but you beat me to it. I've found that the thinner the sidewalls are, the more the tire will grow with use.

  9. #9
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    Quote Originally Posted by vikb View Post
    One thing to be aware of is 29+ tires are going to grow a bit with some use. So if you test fit a tire new and then test fit it again after a few weeks use you'll find it's not got the same clearance.
    This is absolutely true.

    And these thin rubbers will grow even more if you add tubeless sealant later on, might be part of what you are seeing LyNx.. did you measure the tire new and after a few rides?
    ...

  10. #10
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    Quote Originally Posted by LyNx View Post
    Wish you "genius" engineers would just stay in your labs with your "theorectical thinking" and let us real folks get on with life where we actually use and try stuff FOR REAL
    Yes, so stupid people like you can continue to post BS without being challenged.

    I don't care what you've imagined, you can measure the same tire on different rim widths and prove easily that tire diameter doesn't change much. You don't have to be in a lab or engage in "theoretical thinking" to see that, but you do need to be willing to pull your head out of your @ss.

    Your contempt for anyone who doesn't agree with you only grows with time, LyNx. What does that say about you?

  11. #11
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    Here's an old diagram I did of the same size casing varying over a wide range of rim widths. You can see that height does vary but so does the center of curvature. Since the rim on the wheel has a constant radius, the change of center affects the tire height and neutralizes any benefit of effective tire growth.

    I also included a range of real tires with measured b2b dimensions and showed effective casing heights over a broad range of internal widths. The change in height is 1-2% over interesting rims. Big deal.

    Using the Chronicle's b2b number advertised here, the tire's height would vary 0.4mm between the rims LyNx has mentioned. The width, though, would vary 5mm, or about 10 times as much. I guess that qualifies as "mainly height" in LyNx's eyes.

    Incidentally, the Chronicle's height peaks at 40mm internal rim width. Another reason to think that 50mm rims are too large for plus sized tires.
    Attached Thumbnails Attached Thumbnails 29+ Tire Geometries-screen-shot-2015-07-08-7.58.29-am.png  

    29+ Tire Geometries-tireheights.jpg  


  12. #12
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    Ever heard the saying "Pot calling the kettle black?

    Quote Originally Posted by craigsj View Post
    Yes, so stupid people like you can continue to post BS without being challenged.

    I don't care what you've imagined, you can measure the same tire on different rim widths and prove easily that tire diameter doesn't change much. You don't have to be in a lab or engage in "theoretical thinking" to see that, but you do need to be willing to pull your head out of your @ss.

    Your contempt for anyone who doesn't agree with you only grows with time, LyNx. What does that say about you?
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  13. #13
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    You know, completely forget about tyre stretch, had been using the tyre a bit and it was mounted for a decent amount of time (few months), so that coupled with the bigger rim most likely explains the "no fit" that's happening now. Must say, lot of growth compared to "normal" tyres, had fairly decent clearance to ride smooth/groomed dirt trails when I first test fit them -gravel would prob have produced a problem.

    THANKFULLY, there are only a few such "geniuses" on here, the rest like Vikb provide useful and reasonable information.
    Quote Originally Posted by vikb View Post
    One thing to be aware of is 29+ tires are going to grow a bit with some use. So if you test fit a tire new and then test fit it again after a few weeks use you'll find it's not got the same clearance.

    I've found this to be true of all the Surly tires I've either had my hand on or that are on friends' bikes. There are also enough reports of the same thing on MTBR to assume other brands will do the same thing.

    It's no big deal if you have a ton of clearance, but if your setup barely works with a new 29+ tire it's likely that you'll lose enough clearance for it to be an issue as the tire gets used.
    Quote Originally Posted by Deerhill View Post
    This is absolutely true.

    And these thin rubbers will grow even more if you add tubeless sealant later on, might be part of what you are seeing LyNx.. did you measure the tire new and after a few rides?
    One day your life will flash before your eyes, will it be worth watching??

  14. #14
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    It's good to know people are taking the time to try stuff and post what parts work together and what doesn't, bummer when it doesn't.
    ...

  15. #15
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    Quote Originally Posted by craigsj View Post
    Incidentally, the Chronicle's height peaks at 40mm internal rim width. Another reason to think that 50mm rims are too large for plus sized tires.
    why would you want a tire to be as tall as possible? a narrower rim gives less volume and causes the tire to fold over more in corners.

    i would much rather have a wider rim, more volume, lower pressure, more grip, and a tire that is more stable while cornering.

    there is a thread around here somewhere that shows someone mounted a 2.2 tire on a 65mm rim and was happy with the way it rode. granted maybe for a specific application and not ideally suited for normal riding, but no way is a 50mm rim too wide for a + tire.
    Rigid SS 29er
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    Stop asking how much it weighs and just go ride it.

  16. #16
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    Quote Originally Posted by BENKD29 View Post
    why would you want a tire to be as tall as possible? a narrower rim gives less volume and causes the tire to fold over more in corners.
    Because you want the most resistance to rim strikes.

    Less vs. more volume is irrelevant. People think volume matters only because others keep saying it does. What matters is compliance and once people realize that it's not the air volume but the casing size that matters they will stop believing that the widest rim possible is the best. Wide rims help with sidewall stability, the air they add does not help at all.

    Using a 40mm rim rather than a 50mm for plus sizes won't cause "the tire to fold over more in corners". 40mm is already wide.

    Quote Originally Posted by BENKD29 View Post
    i would much rather have a wider rim, more volume, lower pressure, more grip, and a tire that is more stable while cornering.
    Then why stop at 50mm? Why not an 80mm rim instead? Won't it give you even more of these things? You need some perspective, more is not always better.

    Quote Originally Posted by BENKD29 View Post
    there is a thread around here somewhere that shows someone mounted a 2.2 tire on a 65mm rim and was happy with the way it rode. granted maybe for a specific application and not ideally suited for normal riding, but no way is a 50mm rim too wide for a + tire.
    People who come up with stupid ideas, particularly when they spend money on them, are predisposed to like the result.

  17. #17
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    Quote Originally Posted by LyNx View Post
    THANKFULLY, there are only a few such "geniuses" on here, the rest like Vikb provide useful and reasonable information.
    It's sad, LyNx, that you have to be told such remedial things when you pretend to be such an expert. MTBR would be better off with less of your kind of "genius", people come here to learn and egregious errors such as yours presented with hard-headed conviction don't help.

  18. #18
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    Quote Originally Posted by craigsj View Post
    Because you want the most resistance to rim strikes.

    Less vs. more volume is irrelevant. People think volume matters only because others keep saying it does. What matters is compliance and once people realize that it's not the air volume but the casing size that matters they will stop believing that the widest rim possible is the best. Wide rims help with sidewall stability, the air they add does not help at all.
    you said yourself that the difference in rolling diameter was .4mm, do you really think that is going to prevent a rim strike? no. rim strikes are prevented by running the proper air pressure and riding smooth, not plowing into things. your logic makes no sense. i want stability and grip, the rim strikes will be prevented by my riding.

    volume absolutely makes a difference. the first time i mounted a 29er 2.4 tire i had been running on a 21mm rim onto a 30mm rim it was an eye opening experience. i'm sure most here have experienced the same. it gets even better when you go a bit wider. if you want to say it's due to sidewall stiffness fine, but it comes from the wider rim and increased volume. (i also think that heavier riders benefit from this more than lighter riders, and the effect is amplified, which may contribute to the variety of opinions.)

    i do think there is a limit and at a point you reach a diminishing point of returns, and eventually go backwards. i was just giving an example.
    Rigid SS 29er
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    Stop asking how much it weighs and just go ride it.

  19. #19
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    Subscribed---- but just for the data, not the relentless bickering
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  20. #20
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    Wow, only took you two weeks to come up with that spendiferous reply Did the fact that the real world people, who actually go out and experiment and use stuff in the real world and not just draw it up on the computer in the virtual world throw you that much - Wow, tyre stretch, never thought of that one did ya

    Quote Originally Posted by craigsj View Post
    It's sad, LyNx, that you have to be told such remedial things when you pretend to be such an expert. MTBR would be better off with less of your kind of "genius", people come here to learn and egregious errors such as yours presented with hard-headed conviction don't help.
    One day your life will flash before your eyes, will it be worth watching??

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    Updated the table in the first post with the measurements for the Innova Gravity Vidar 29+ on a 35mm rim (Velocity Blunt 35).

    Overall mounted outside diameter: 767mm
    Width knob-to-knob: 74mm
    Width casing: 71mm

    This means the tire is pretty much the same diameter as the Surly Knard, Bontrager Chupacabra & Vee Fatty Trax. I have a pair of Maxxis Chronicles on the way and will post the measurements for those eventually.

    I started this thread to figure out which tire will have the most clearance under the fork's arch when fitted on my Fox 32 F29 fork. That tire is still the Surly Dirt Wizard by far, but alas far from ideal tire for my riding conditions. The Panaracer Fat B Nimble has about 2-3mm more clearance than most of the others.

    Btw, I added a blog post about my unexpectedly successful attempt to mount the Gravity Vidars tubeless on my Blunt 35s.

    Innova Gravity Vidar 29+ tubeless setup on Velocity Blunt 35

  22. #22
    mnt bike laws of physics
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    The Bomboloni is 10mm shorter than the Gravity, so would give you 5mm more clearance.

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    Quote Originally Posted by yogiprophet View Post
    The Bomboloni is 10mm shorter than the Gravity, so would give you 5mm more clearance.
    Thanks! Did you measure the Bomboloni at 757mm? That makes it about the same as the Surly Dirt Wizard. Where did you track down the Bomboloni?

  24. #24
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    can you prove that tyres, when inflated, tend to circular cross section (as in your diagram) ? (albeit with a varied flat section that is the rim)

    given the variance in thickness and materials at different circumferential points, i am not convinced that it would be the case. i dont know though, so would love to see your evidence.

    i see it a bit like blowing up a ballon with a strip of tape on it.

    in addition, and perhaps making the above a non-issue, the effective point of contact of the tyre is when it hits the ground. what happens at any other point is irrelevant. the ground clearly deforms the tyre and this varies with pressure as well as tyre structure and size, right? so how does this affect your calculations?

    apologies if you have, elsewhere, already dealt with this, but could you point me to it?

    Quote Originally Posted by craigsj View Post
    Here's an old diagram I did of the same size casing varying over a wide range of rim widths. You can see that height does vary but so does the center of curvature. Since the rim on the wheel has a constant radius, the change of center affects the tire height and neutralizes any benefit of effective tire growth.

    I also included a range of real tires with measured b2b dimensions and showed effective casing heights over a broad range of internal widths. The change in height is 1-2% over interesting rims. Big deal.

    Using the Chronicle's b2b number advertised here, the tire's height would vary 0.4mm between the rims LyNx has mentioned. The width, though, would vary 5mm, or about 10 times as much. I guess that qualifies as "mainly height" in LyNx's eyes.

    Incidentally, the Chronicle's height peaks at 40mm internal rim width. Another reason to think that 50mm rims are too large for plus sized tires.
    Last edited by dRjOn; 09-25-2015 at 02:33 AM. Reason: spelling

  25. #25
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    so i got to thinking about this a bit more. i dont know too much about the physics, but i do know i like the combination of a higher volume tyre at lower pressure for my relatively low speed, reasonable tech riding on a hardtail or rigid bike.

    why is that?

    considerations for tyres (and or wheels):

    Comfort
    Control/traction
    Rolling resistance
    Puncture resistance
    Rim durability
    Weight


    my thoughts:

    Lower pressure = more comfort given same casing construction

    A bigger volume tyre feels similar to a small volume tyre at less pressure (pounds per square inch…I guess it is self explanatory) given similar casing

    Less aggressive tread gives less rolling resistance given same casing construction and size (I don’t know how true, but for truck tyres, figures of 60-70% of the rolling resistance is associated with the tread design)

    increased hysteresis can lead to increased rolling resistance ('tacky' DH tyres anyone?)

    increased hysteresis gives more traction ('tacky' DH tyres anyone? :-)~)

    less tyre pressure is unlikely to make you slower (increase rolling reistance) given the range that is realistic for bikes. it is also probably unlikely to make you faster if considered in isolation

    bigger volume tyres create a bigger foot print in general, though pressure and casing design affects this

    bigger foot print is associated with more traction

    lower pressure tyres can lead to pinch flats with tubes, and rim strikes

    casing design can be beefed up (specifically on the sidewall) to mitigate this, but then the tyre becomes less supple – see hysteresis

    casing design can reduce or promote sidewall wear and piercing type puncture risk

    So: a bigger tyre volume, with a lower pressure, and less aggressive tread might provide similar or better traction than a smaller, narrower tyre
    it might roll at the same speed (or perhaps faster if the tread allows) and it might be more comfortable.
    If it is made well - with good quality casing - it might not wear fast or be at risk from punctures and it might not be too heavy. Given the whole light strong cheap triumvirate, it is unlikely to be inexpensive.

    Depending on how you load the tyre this may be a *good thing*. If it is more likely to flop around on the rim (too narrow a rim, or just high bulbosity) and is used in a high speed/direction changing terrain, it might feel more vague. This is probably why enduro racers/DHers are using no more than 2.5” tyres I suspect?

    i guess that is why i like em?

    now - i am no expert - this was purely typed as a vague self assessment. id love to hear if anyone else has any thoughts on all this. yes, even craigsj! :-)~
    Last edited by dRjOn; 09-25-2015 at 01:31 PM. Reason: Spelling. Yet again!

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    Quote Originally Posted by dRjOn View Post
    can you prove that tyres, when inflated, tend to circular cross section (as in your diagram) ? (albeit with a varied flat section that is the rim)

    given the variance in thickness and materials at different circumferential points, i am not convinced that it would be the case. i dont know though, so would love to see your evidence.

    i see it a bit like blowing up a ballon with a strip of tape on it.
    No, that can't be done generally, especially considering that tire construction could change. It would be true for tires that had uniform casing construction as they largely do, but variations could cause some deviation from round. The balloon analogy is a good one, though casings aren't that stretchy of course.

    More important than a tire's variance, though, is how much tires vary from one another. They will all deviate from round in the same ways because they have the same trends in construction. To me, what's important is how tire compare to one another, not how precisely one tire is modeled.

    I've done a lot of measurements while developing my model and I don't see a great deal of variance. There will always be some for plenty of reasons, one of which is this issue you bring up. The answer is to manage expectations, you can get within a few percent but should expect any more.

    Quote Originally Posted by dRjOn View Post
    in addition, and perhaps making the above a non-issue, the effective point of contact of the tyre is when it hits the ground. what happens at any other point is irrelevant. the ground clearly deforms the tyre and this varies with pressure as well as tyre structure and size, right? so how does this affect your calculations?
    Yes, yes, yes! I've been saying this and certainly agree.

    My model shows that tire diameter isn't really affected by rim width, so that doesn't change here.

    Clearly a tire under load will have a different shape so my width calculations won't be valid. That would be an interesting challenge to show width under load for narrow vs. wide rims.

    If a tire stretches, does it shrink back under load? To what extent is stretch even meaningful?

    This point you make is what's really interesting, not anything else that's commonly talked about. A tire deforms based on load, pressure, and construction, for sure, but is the rim width involved? Also, how does the existence of tread impact this? A smooth tire's contact shape would definitely change with rim width but does a knobby tire? People think wide rims make tires wider but they do not for these reasons; they do make tires work better though.

  27. #27
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    Quote Originally Posted by dRjOn View Post
    now - i am no expert - this was purely typed as a vague self assessment. id love to hear if anyone else has any thoughts on all this. yes, even craigsj! :-)~
    I think all of that is well thought out and I agree.

    Where I object is in the use of the word "volume" as a substitute for casing size. It's true that tire volume and casing size are directly related, but a wide rim will increase volume without increasing casing size. We want big casings and proportional rims, not the same casings on oversized rims (IMO).

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    Recently I read or heard that a computer with the capabilities of the human brain/mind would require a space the size of a good sized warehouse.
    I don't have a cite for that so let's just put it down as a supposition. I apply that to my evaluation of my bike's performance as it goes over varying trail terrain. I can use that to perceive differences in tire performance from pressure, rim width, tread wear level and profile. No graph or equation is anywhere near good enough to help communicate what goes on. Demoing is the way to go. Maybe a friend's setup or one of the 27.5+ or 29+ bikes at a demo day will become available. Use that opportunity to get the info you need. Your own perceptions will tell you what you need to know.

  29. #29
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    Quote Originally Posted by eb1888 View Post
    I can use that to perceive differences in tire performance from pressure, rim width, tread wear level and profile.
    Your brain is notoriously terrible at measuring differences objectively. Even the most primitive computers, even calculators, are far better at such things.

    Without "graphs and equations" we wouldn't have bicycles to begin with.

  30. #30
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    I've been using the Bomboloni for about two months now. You should be able to get one just about anywhere. QBC has them I heard.

    I've been running all my 29+ tires on 50mm OD rims. I have all the measurements on my garage wall. All measured after stretching and the Bomboloni is somewhere between the DW and Gravity. I'll post up the heights here soon, but what I wrote above is correct, and I measure with a level.

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    Haven't been riding for over 6 weeks due to a simple fracture (got lucky) of my C-1 vertebrae, so I have the spare time and extreme boredom needed to measure my tires and further waste some more of it here on the forums;-p

    My Bombolonis only had about 60 miles on 'em before I was forbidden to ride and became sentenced to wearing this neck brace. They're on 50 mm Rabbit Holes.
    They had aired down to around 8 or 9 lbs, so I pumped 'em up to 14, mainly to generate some excitement, and ensure that the bike is ready to ride when my doc says its OK.

    Bombo casing is barely 72 mm. approx 71.8, maybe
    Tread-to-tread measures approx 73.5 mm. I had to measure using a straightedge on each side, since the outer tread knobs aren't directly opposite from the ones on the other side of the tire, but are staggered.

    Didn't measure the diameter.

    My tires are fairly new, and may stretch with more use.

  32. #32
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    I almost forgot to ask: Are we gonna get a 29+ x 3.5" tire to bridge that final gap between 29+ and 26 x 3.8" fat? Something that might free the 29+for truly cavorting on the beach?
    Or is 3.25" all we gonna get?

    Edited 2/28 to correct brainfart error.
    Last edited by PlutonicPlague; 02-28-2016 at 11:39 AM.

  33. #33
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    Quote Originally Posted by PlutonicPlague View Post
    Are we gonna get a 29+ x 3.5" tire to bridge that final gap between 29+ and 4 x 3.8" fat?
    What is a 4 x 3.8" fat? If you are referring to 26x3.8", 29ers are bigger than that already.

    A 29x3.25 is larger in diameter than the largest 26" fat bike tires.

  34. #34
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    Thanks for catching that glaring error.
    Yes, I can see by comparing my wheels that 29+ tires are larger in diameter than 26" fat bike tires.
    My experience riding on the beach here with various 26" fat bike tires has left me with some opinions. My 26" Fat B Nimbles are less than 3 3/8" wide when inflated to beach riding pressures. As a result of this relative skinniness, they don't float nearly as well as a fatter fat tire on the soft sand. So I don't like them for beach riding. Every other fat tire that I have tried on the beach has been noticeably better on the various textures of the beach sand. My Halo Nanuks aren't much wider, at only 3.5" wide, but they roll much nicer on the sand than FBNs due to their tread design.
    I swap over to the FBNs for riding logging roads and trails.
    Knards, with their fatter casing, are better on the sand than the FBNs. They are mounted on my SS wheel set, which is "mothballed" and stored for now.
    My fat rims are 65mm Marge Lites.
    MY next set of fat tires will be selected from among the widest that will fit on my Pugs. That's way out in the future, at least a year from now.

    So, for my 29+ wheels, I wouldn't mind a fatter tire. I really like my Bombolonis, but they don't like softer sand, so I generally stay off the beach when rolling on 29+. I will blitz downwind the 6+ miles to my house (from Westport to my house in Grayland) on the hard packed sand at low tide on my Bombo'ed Krampugs, if the tide is out and the wind is from the N or NW. Its a nice fast beach ride, then.
    I'll roll on the Bombos for this year, but when they start showing some wear, I'll be ready to try something different.
    I'd like to see a Vee Bulldozer 29 x 3.25" mounted on a Rabbit Hole, and measure the actual width.

  35. #35
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    I see the gap in tire size being between 2.5 x 29 and 2.8 x 29. Can't wait to see more, if it ever happens.

  36. #36
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    The 29 x 25 Gap is about to be closed in just a few days. Word on the forums from Trek is that these should be available any day now since it is June 1st today.

    Updated Bontrager XR4 and SE4 Team Issue Tires - 2016 Sea Otter Classic Pit Bits - Mountain Biking Pictures - Vital MTB

    I agree with you that a 29 x 2.8 would be highly desirable as it would fit the vast majority of 29'er suspension forks out there right now.

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