Results 1 to 12 of 12
  1. #1
    mtbr member
    Reputation:
    Join Date
    Dec 2016
    Posts
    6

    Stumpjumper 6Fattie w/ 3.8 Fat Tires?

    I know you're all thinking not another wheel/tire combo thread or tell me to go read the 'official' thread on this, but I've done a lot of searching and have not found my answer.

    So, for those of you who have tried to maximize the rim/tire size in your SJ6F, can any of you tell me whether a 3.8 Hodag on a 50mm rim will fit the frame and clear the chain? I just would like to know the feasibility of this as I am very much considering building this bike. I love fat biking but I also miss my full squish, so I wanted to see if it's possible to combine these two platforms for a unique build to satisfy my taste. I know there is the Bucksaw and Mutz to accomplish this, but I am a fan of Specialized and I don't know if they will ever have any FS fat bikes.

    While on the topic, what is the BB width on this bike?

    Are the frames/rear triangles the same on the 29" and 6F versions of this bike? It appears the same from the geometry chart but can someone confirm?

    Thank you!

  2. #2
    mtbr member
    Reputation:
    Join Date
    Jan 2017
    Posts
    6
    Did you find an answer to this? I'd like to know as well.

  3. #3
    mtbr member
    Reputation:
    Join Date
    Sep 2015
    Posts
    124
    I can tell you almost certainly that you will have trouble with chain clearance. Also yes as of 2017 the rear triangle on the 6fattie and 29er are the same. They were different in 2016 but it changed this year.

  4. #4
    mtbr member
    Reputation:
    Join Date
    Dec 2016
    Posts
    6
    Thanks McKenzie for the input. I was figuring that would be the case. Think I'll be going a different route.

  5. #5
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    5
    I've been running the Hodags on the stock wheels for a few months now. They measure about 3.5" at the widest nob on the stock wheels. Really like them and the floatation they provide over the rocky terrain that we have here in northern jersey. The sidewalls seem substantial enough to resist folding over even as low as 10-12psi. I rode them at 6-7 psi in fresh snow as well. Traction was great with sipes. They fit fine other than chain rub on the lowest two gears and ice packing up if i do a water crossing in freezing temps.
    Stumpjumper 6Fattie w/ 3.8 Fat Tires?-hodags.jpg
    Stumpjumper 6Fattie w/ 3.8 Fat Tires?-hodag2.jpg
    Stumpjumper 6Fattie w/ 3.8 Fat Tires?-hodag3.jpg
    Attached Thumbnails Attached Thumbnails Stumpjumper 6Fattie w/ 3.8 Fat Tires?-hodags.jpg  


  6. #6
    mtbr member
    Reputation: madmark's Avatar
    Join Date
    Feb 2008
    Posts
    207
    I would say the rear tyre would be too wide for the rear and looking at the picture above there is hardly any clearance, so you will certainly have a high risk of sawing through the stay with the tyre. With tyre flex and roll its a big risk running a 3.5 inch tyre.
    Home trails Swinley Forest UK

  7. #7
    mtbr member
    Reputation:
    Join Date
    Feb 2016
    Posts
    17
    i am very interested in this, could you shed more info?
    and pix with diff angles?
    thanks

    Quote Originally Posted by pescatom View Post
    I've been running the Hodags on the stock wheels for a few months now. They measure about 3.5" at the widest nob on the stock wheels. Really like them and the floatation they provide over the rocky terrain that we have here in northern jersey. The sidewalls seem substantial enough to resist folding over even as low as 10-12psi. I rode them at 6-7 psi in fresh snow as well. Traction was great with sipes. They fit fine other than chain rub on the lowest two gears and ice packing up if i do a water crossing in freezing temps.
    Click image for larger version. 

Name:	Hodags.jpg 
Views:	52 
Size:	311.0 KB 
ID:	1119905
    Click image for larger version. 

Name:	hodag2.jpg 
Views:	69 
Size:	89.6 KB 
ID:	1119908
    Click image for larger version. 

Name:	hodag3.jpg 
Views:	80 
Size:	142.6 KB 
ID:	1119909

  8. #8
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    5
    Hi - The clearance is barely enough. I do have some paint removal on the inner swing arm, but nothing major. That said I did grind down the offending edge of the knob - probably a millimeter or two. Solved the issue. No rubbing at all now.

  9. #9
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    5
    What more do you want to know? What sort of angles?

  10. #10
    mtbr member
    Reputation:
    Join Date
    Feb 2016
    Posts
    17
    how bad is the chain rub in the last 2 cogs that you mentioned? thank you for this! been searching for this for a while, i just done building a '17 Stumpy, and if this works, i would be supper happy

  11. #11
    mtbr member
    Reputation:
    Join Date
    Mar 2007
    Posts
    5
    Stock, it's bad on the last gear, not so bad on the next one. Was also rubbing the swing arm and it did remove the paint a bit on both sides (around the size of two grains of rice side by side). I shaved the edge of the knobs with a grinder - took 10 minutes. I also swapped my chainring to a zero offset so that helps as well. Now its a lot better. No rub at all on the swingarm. Barely rubs on the second highest gear, and just a little annoying.

  12. #12
    mtbr member
    Reputation:
    Join Date
    Feb 2016
    Posts
    17
    gotcha, thank you!

Similar Threads

  1. 27.5+ Stumpjumper 6Fattie
    By fc in forum 26+/27.5+/29+ Plus Bikes
    Replies: 3116
    Last Post: 17 Minutes Ago, 05:34 AM
  2. 27.5+ Stumpjumper 6Fattie
    By fc in forum Specialized
    Replies: 285
    Last Post: 08-17-2017, 08:16 PM
  3. Questions about Stumpjumper 6Fattie
    By OffTheTop in forum 26+/27.5+/29+ Plus Bikes
    Replies: 8
    Last Post: 06-09-2016, 07:56 AM
  4. Replies: 2
    Last Post: 05-16-2016, 10:01 AM
  5. Stumpjumper FSR Comp 6Fattie
    By GrantM in forum 26+/27.5+/29+ Plus Bikes
    Replies: 19
    Last Post: 03-21-2016, 12:50 PM

Members who have read this thread: 9

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •