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Maximum Tyre width

MattyB85MattyB85 Posts: 25
edited January 2018 in MTB beginners
Afternoon all,

I'm the proud owner of a 2018 Giant Fathom 2. Giant supply these with Maxxis Ardent tyres in 2.25 width. They are poor in the wet/mud and feel pretty poor in anything other than completely dry conditions. I've played around with pressures but being quite a heavy guy I need to run them relatively hard.
I've been recommended some Nobby Nic's but have seen they come in a variety of widths. I'd like to go wider but not sure what the maximum is I can get away with. Schwalbe do a 2.6 Nobby Nic, anyone know if it would fit?

Cheers

Posts

  • robertpbrobertpb Posts: 1,866
    And this relatively hard is, your weight is, better to get the basics right before you start spending.
    Now where's that "Get Out of Crash Free Card"
  • MattyB85MattyB85 Posts: 25
    Sorry- relatively hard= 40 ish psi
    Weight= 14.2 stone
  • robertpbrobertpb Posts: 1,866
    In the mud with your weight that size tyre tubed I'd be running around 30psi.
    In the mud with a tubeless 2.35 tyre I'm down to 18psi in the front for grip.
    Now where's that "Get Out of Crash Free Card"
  • MattyB85MattyB85 Posts: 25
    Not really too fussed about what pressure's I'm running, as long as I'm running well and it all feels good when out. I know that with lower pressures I'm feeling like I'm hitting the rim on roots & rocks so keep enough in to make the ride better for me.

    My question is simply what is the widest tyre I can fit on my Giant Fathom 2
  • JGTRJGTR Posts: 1,404
    Get a ruler and measure it, just bear in mind that some tyres are slightly different from the states width, factor that into your descision.

    I would also say that 40 psi may be a bit on the high side.
  • MattyB85MattyB85 Posts: 25
    Cheers JGTR- I did wonder if the stated width and the actual width may differ- hence me asking if anyone knew for sure.

    I'll get the tape measure out tonight and see what I have to play with unless anyone can answer it definitively before then.

    And yeah, 40psi is high- but I'm a fat censored at the moment so need the extra pressure to save the rims
  • JGTRJGTR Posts: 1,404
    I’m heavier and run 25 psi on 2.4”
  • MattyB85MattyB85 Posts: 25
    Wowzer... I always feel as if i'm smashing the rear wheel to pieces when going over roots. Currently on a 2.25 so there may be more difference than I thought in the difference in capabilities between the sizes. (also I'm not tubeless, yet)

    Or perhaps you're just a little more nimble on the trails than I am...
  • JGTRJGTR Posts: 1,404
    I’m riding 2.4” x 29” - you can run a bit lower with 29” wheels. Nimble is something that I am not :lol:
  • The RookieThe Rookie Posts: 27,809
    Probably feel like your smashing the wheel as the tyre is too hard and not absorbing anything!

    I ride with a guy who’s similar weight to you, and on a fathom, he’s at 30psi, I’m only 9 pounds lighter (about 5% of the rider plus bike weight) and run 28 in the rear on a similar sized tyre.
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • MattyB85MattyB85 Posts: 25
    The Rookie wrote:
    Probably feel like your smashing the wheel as the tyre is too hard and not absorbing anything!

    I ride with a guy who’s similar weight to you, and on a fathom, he’s at 30psi, I’m only 9 pounds lighter (about 5% of the rider plus bike weight) and run 28 in the rear on a similar sized tyre.


    I'll give it a go... is he using the standard Maxxis Ardent's that come supplied? 27.5?
  • The RookieThe Rookie Posts: 27,809
    Yup.....
    Current steed - Whyte T129, 2013 frame, mongrel Revelations, Giant dropper, Stans S1 wheelset. 12, Magura Trail Sport brakes, 1x11. 12.8Kg
  • slc123slc123 Posts: 407
    I run a set of 2.25 Ardents on my XC bike and ride in the worst conditions in muddy trails. I'm lighter than you, but tend to ride my bike pretty hard. I drop to high 20s to ride in the mud and get a decent amount of grip. There are better tyres for muddy conditions but I find these pretty all round.
    Cannondale Trail 27.5 | 2015
    Titus El Chulo 27.5 | 2017
    Trek Slash 9 27.5 | 2015 (building)
  • mattyfezmattyfez Posts: 638
    I'm 16 stone and run 30-33 psi f/r, 40 sounds way to high to mee too.
  • MattyB85MattyB85 Posts: 25
    slc123 wrote:
    I run a set of 2.25 Ardents on my XC bike and ride in the worst conditions in muddy trails. I'm lighter than you, but tend to ride my bike pretty hard. I drop to high 20s to ride in the mud and get a decent amount of grip. There are better tyres for muddy conditions but I find these pretty all round.
    mattyfez wrote:
    I'm 16 stone and run 30-33 psi f/r, 40 sounds way to high to mee too.

    I'll give high 20's to around 33 a go then and see how I get on. Cheers guys.
  • cyclecliniccycleclinic Posts: 6,865
    are you running the tyres tubeless, if not convert and use 25 psi max. That cures all sort of problems at a stroke.
    http://www.thecycleclinic.co.uk -wheel building and other stuff.
  • davidradardavidradar Posts: 69
    Hello. Okay I Googled your pushbike and found it has XC-2 Rims. I am not sure if I got the correct specs from the giant website but I referenced the 29"

    If you do some further research there are maximum and minimum tire width recommended by manufactures of rims. I know mine are DT Swiss and there website states this info. Just having a quick look at I would think 2.4 would be the max recommended for 19mm wide rims. I would take the previous poster advice and go tubeless if not already.


    XC-1 is 23mm wide
    XC-2 is 19mm wide
    Stay positive people :)
  • MattyB85MattyB85 Posts: 25
    thecycleclinic wrote:
    are you running the tyres tubeless, if not convert and use 25 psi max. That cures all sort of problems at a stroke.
    DavidRadar wrote:
    Hello. Okay I Googled your pushbike and found it has XC-2 Rims. I am not sure if I got the correct specs from the giant website but I referenced the 29"

    If you do some further research there are maximum and minimum tire width recommended by manufactures of rims. I know mine are DT Swiss and there website states this info. Just having a quick look at I would think 2.4 would be the max recommended for 19mm wide rims. I would take the previous poster advice and go tubeless if not already.


    XC-1 is 23mm wide
    XC-2 is 19mm wide

    Thanks chaps for both of these comments... No I'm not tubeless but it is on my 'to do' list.

    The wheels are XC2's but the Giant website states a inner width of 21mm. I have the 2018 27.5 version.

    https://www.giant-bicycles.com/gb/fathom-2-2018
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