Page 1 of 3 1 2 3 LastLast
Results 1 to 25 of 62
  1. #1
    mtbr member
    Reputation:
    Join Date
    Nov 2007
    Posts
    7

    What Frame Size to Buy?

    Finally decided on the Mojo SL but I have noticed quite a few guys have gone up a frame size. I am 6'2", 34" inseam and 200lbs. The other two bikes I ride quite a bit and like are the Cannondale Rush and Spec. Epic. I would appreciate some guidance. I have done a little chart below comparing relevant (?) measurements,

    Frame Size Comparison for Large Frames

    Wheelbase
    Cann Rush 1131 mm
    Sp Epic 1127
    Ibis Mojo 1105 (xl is 1126)

    Top Tube (effective)
    Cann Rush 625 mm
    Sp Epic 615
    Ibis Mojo 600 (xl is 620)

    Chainstay Length
    Cann Rush 422 mm
    Sp Epic 427
    Ibis Mojo 429
    Last edited by splurf; 01-01-2008 at 01:12 AM.

  2. #2
    mtbr member
    Reputation:
    Join Date
    Nov 2007
    Posts
    7

    From Ibis

    Here is the reply to my own question that I got from the Ibis dealer in Australia

    Hey John:
    Well… I’m 5’ 8” and I ride a medium…

    Rick is 5’ 11” and he rides a large…

    Dale is 6’ and he rides a large…

    The standover height only varies slightly as you jump from Large to X-Large.
    Measured at middle of top tube 

    Size: Standover height 

    XL: 31.3" 

    L: 31"

    So as you see… you’re looking at less than ½ inch difference in standover. However top tube length increases by almost an inch:
    Size: Top tube length
    XL: 24.4”
    L: 23.6”

    At 6’ 2”… I’d suggest you go with an XL. (due at the end of Jan)

  3. #3
    Keep Riding !!
    Reputation: AussieRider's Avatar
    Join Date
    Dec 2006
    Posts
    167
    I'm 6'2" with a 34" (about) inseam 180 lbs, Ibis themselves, when asked, recommended a Large however the LBS recommended an Extra Large

    I ended up going with the XL, 1st with a 120mm stem and found it the correct size certainly not to large
    After about 11 months I've recently changed to a 100mm stem more to change the handling rather than reduce any stretched out/too long feel and found that with the shorter stem I'm more 'on top' of the steering

    As you can tell from your own comparison the Ibis Mojo tends to be on the small side for any given size.

    If you like tight/technical tracks you may prefer the Large to enable you to 'chuck' the bike about a bit but I would recommend from my own experience the XL for someone your size
    Just Ride !

  4. #4
    mtbr member
    Reputation:
    Join Date
    Nov 2007
    Posts
    15
    Hi to all, I'm having the same question as splurf. I've decided to go for the Mojo SL but after I wrote to the ibis people the answer was you can choose both L and XL.
    So as you all understand I'm more confused than ever
    I'm 1.86cm (6'1"), 91cm (35") inseam and 93kg(205lbs) and I want your opinion
    what to choose L or XL ?????
    please help

  5. #5
    mtbr member
    Reputation:
    Join Date
    Dec 2007
    Posts
    32
    having the same debate here too, I normally ride 19" bikes, I am 6.2, I tested a large and it felt ok, but looked small with me on it, so now worried if I go XL it will be like a gate.

  6. #6
    Keep Riding !!
    Reputation: AussieRider's Avatar
    Join Date
    Dec 2006
    Posts
    167

    XL Mojo

    Not the greatest photo but this is my XL Mojo, as per previous post I'm 6'2" & 34" inseam and it doesn't look like a farm gate to me.
    The only real difference now is the bike now has 140mm Forks (Pace) instead if the 130mm ('04 Fax Talas), a zero offset post & shorter stem
    Attached Images Attached Images
    Just Ride !

  7. #7
    mtbr member
    Reputation: Tall Tom's Avatar
    Join Date
    Oct 2005
    Posts
    87
    Quote Originally Posted by Quentinfarquar
    having the same debate here too, I normally ride 19" bikes, I am 6.2, I tested a large and it felt ok, but looked small with me on it, so now worried if I go XL it will be like a gate.
    Tom from Ibis posting. In general, we would recommend that some one 6'2" or shorter go with a large frame vs. an XL.

    The comparison of top tube length with your previous bikes can be tricky unless your previous bike had a 69 degree heaad tube angle.

    Our approach with the Mojo was that with 140 mm of travel and a 69 degree head tube angle the top tube lengths should be a little shorter than if you were riding a more cross country oriented bike with a 70 or 71 degree head tube angle. The theory being that the slacker head tube angle - in addition to providing more steering stability - pushes the front wheel farther out in front of you. On steep terrain this is fine, but on rolling twisty stuff there can be tendancy to push the front end because you don't have enough weight on the front wheel. With the Mojo we felt that the slightly shorter top tube would allow you to use a slightly longer stem, thus maintaining a better weight distribution over the bike for better all around handling.

    It seems - based upon the feedback of folks who have bought Mojos - that the sizing has worked out well for most people.

    Keep in mind that the head tube length increases as you go up a size as well. This could make it difficult for you to get down low enough - depending on your preferred riding position.

    If you have any further questions feel free to contact us directly.

    Happy Trails!

    PS - Before the XL tooling was finished I (6' 6") rode a large for several months and it was fine. So I don't think you'll have any trouble with the Large.

  8. #8
    mtbr member
    Reputation:
    Join Date
    Dec 2007
    Posts
    32
    Cheers Tom, sounds like good advice... you mentioned you intended for a longer stem, what size stem for me on a large with 140mm forks, I would normally go 80mm.

    My previous bike I was riding was a Blur LT, and on paper tha frames are very similar size.

  9. #9
    mtbr member
    Reputation: Tall Tom's Avatar
    Join Date
    Oct 2005
    Posts
    87
    Quote Originally Posted by Quentinfarquar
    Cheers Tom, sounds like good advice... you mentioned you intended for a longer stem, what size stem for me on a large with 140mm forks, I would normally go 80mm.

    My previous bike I was riding was a Blur LT, and on paper tha frames are very similar size.
    Since your Blur LT is so similar in size and geometry to the Mojo I would suggest sticking with the 80 mm stem if you like your current riding position. That said, we had a little longer stem in mind when we designed the bike - something like a 90~110 mm stem.

    To a certain extent, I think riders have been influenced to go with shorter stems over the past few years because of the prevailing trends and not necessarily because of the relationship with the bike's overall design. Quite a few bikes with similar travel to the Mojo have longer top tubes and consequently the rider is probably better off with a shorter stem, but - as I mentioned in my previous post - that is not without its downside. The point being that stem length, steering geometry and top tube length need to be considered as a whole.

    That said, there are few absolutes. We determined the Mojo's geometry based upon our personal preferences and experience. If your current set up works for you there's nothing wrong with it. The shorter stem will mute your steering input creating a sort of understeer which may be desirable. The weight balance I described as a result of using the longer stem can still be achieved with the shorter stem by simply lowering your shoulders (mimicking the longer stem position) as needed because the top tube length and head tube angle are the same.

    Hope that answers your question.

  10. #10
    mtbr member
    Reputation: Portti's Avatar
    Join Date
    Jan 2004
    Posts
    219
    This thread is interesting but also a little bit confusing to me. I seem to recall from some previous threads that some people have chosen one size bigger Mojo frame than normally. However based on this thread the frame size should possibly not be bigger but people should opt for a longer stem than normally.

    Personally I'm 191 cm (approx. 6'3"?) and my inseam is 92.5 cm (approx. 36.4"). At the moment my ride is Rocky Mountain ETSX-Team 20.5" which has 615 mm top tube length, 70.5 deg head tube angle and 73 deg seat tube angle.

    I would think that XL would be the only choice for me as far as Mojo goes. The top tube is 620 mm, the head tube angle 69 deg and the seat tube angle 73 deg on the XL Mojo so there would be a slight difference in the head tube angle but otherwise XL Mojo would be quite similar to the ETSX.

    I'm pretty happy with the seating position on my ETSX except for the fact that I would like to get the handlebars a little bit higher but that's difficult since the steerer tube of the fork is too short for that. My stem is adjustable Syntace VRO stem so I don't know the actual stem length at the moment.

    Am I correct in still thinking that the XL would be a good size for me? I was considering a 90 mm stem on the XL frame but now I'm not sure about that.
    Pertti
    Lahti, Finland
    MC Kramppi

  11. #11
    mtbr member
    Reputation:
    Join Date
    Dec 2007
    Posts
    32
    The Uk dealer thinks I should get a XL with a 90mm stem, as he is 6ft and rides a Large and reakons it's just on the limit for him. All this worry thou for 1/8th of an inch....

  12. #12
    www.derbyrims.com
    Reputation: derby's Avatar
    Join Date
    Jan 2004
    Posts
    6,788
    I'm was your size exactly until a car wreck I was a passenger in messed my back up and I shortened 1 inch to be now 6'1” 32 inseam, 200 lbs. I like my Large Mojo for more technical tight slower difficult and rough trails and everything faster too. If you prefer more open mostly high-speed trails then the longer wheelbase of the XL would be even more stable.

  13. #13
    mtbr member
    Reputation: Tall Tom's Avatar
    Join Date
    Oct 2005
    Posts
    87
    Quote Originally Posted by Portti
    This thread is interesting but also a little bit confusing to me. I seem to recall from some previous threads that some people have chosen one size bigger Mojo frame than normally. However based on this thread the frame size should possibly not be bigger but people should opt for a longer stem than normally.

    Personally I'm 191 cm (approx. 6'3"?) and my inseam is 92.5 cm (approx. 36.4"). At the moment my ride is Rocky Mountain ETSX-Team 20.5" which has 615 mm top tube length, 70.5 deg head tube angle and 73 deg seat tube angle.

    I would think that XL would be the only choice for me as far as Mojo goes. The top tube is 620 mm, the head tube angle 69 deg and the seat tube angle 73 deg on the XL Mojo so there would be a slight difference in the head tube angle but otherwise XL Mojo would be quite similar to the ETSX.

    I'm pretty happy with the seating position on my ETSX except for the fact that I would like to get the handlebars a little bit higher but that's difficult since the steerer tube of the fork is too short for that. My stem is adjustable Syntace VRO stem so I don't know the actual stem length at the moment.

    Am I correct in still thinking that the XL would be a good size for me? I was considering a 90 mm stem on the XL frame but now I'm not sure about that.
    Hello Portti,

    Tom from Ibis posting again. At 6'3" you're right where I begin recommending an XL. Also, your desire to get a little bit higher in front reinforces that - as the XL has a taller head tube. So yes, I think that the XL would be right for you.

    Happy New Year everyone!

  14. #14
    mtbr member
    Reputation:
    Join Date
    Feb 2007
    Posts
    42
    I find this thread very helpful and timely! I just put a deposit on a new Mojo SL and need to confirm sizing. I'm 5 foot 10 inches tall with a 32 inch inseam and typically fall in between sizes for most manufacturers ... e.g. Santa Cruz. I currently have a medium Intense 5.5 (medium) with a 4.25" stem and straight seatpost. This setup works for me, but does put more weight on the front of the bike on steep descents.

    I've received conflicting feedback on whether I should go with a Large and shorter stem (e.g. 90 mm) or a medium with a 110 mm. I do not want to use a seatback seatpost. I would appreciate any further insight into this as I decide on frame size for a complete SL. Riding conditions where I ride include XC, AM and some pretty steep climbs and descents. I know I can make either work by fiddling with the seat adjustment and stem length, but I want to get this right in terms of design and bike geometry.

    So, Tall Tom, if you're still on the board, let me know what Ibis would recommend. I need to lock this down Wednesday this week.

    Thanks!

  15. #15
    mtbr member
    Reputation:
    Join Date
    Sep 2006
    Posts
    171
    I went to a Serotta deler and paid to have a bike fit. It was well worth it for me. I am 5'9" with a 34 1/2" inseam. This makes it difficult to say the least. I have recently read that top tube should be determined by torso length and seat tube by inseam length. This makes a lot of sense to me but with my long femurs and short torso I have to go for a longer frame to get knee over pedal spindle or close to it.

    At the same time I have had to fool with shorter stems and longer stack heights to have a less aggressive position then my Serotta fit recommended. Being an old roadie converted to trails I was comfortable long, low and stretched out but I had a hell of a time getting my front wheel up.

    Where I ride there are a lot of logs, roots, and such. Interspersed with areas of soft sand. Being able to easily unweight the front wheel is critical around here in South Florida. In the year and a half I have been trail riding I have discovered that having the correct cockpit and being in the right place within makes all the difference in having a bike that you're happy with. I had to go through a few to learn that. Luckily some very experienced and savvy riders in the club I am in helped me sort it out. Good luck with your new bike.

  16. #16
    mtbr member
    Reputation:
    Join Date
    Feb 2007
    Posts
    42
    Tat2niner,

    So, what size did you end up with?

  17. #17
    mtbr member
    Reputation:
    Join Date
    Nov 2007
    Posts
    7

    Getting more confused.......

    After talking to Ibis here in Australia and listening to some of the above posts recommending an XL Mojo for my size I went ahead and ordered an XL for delivery in January. But now with Ibis in the US seeming to recommend a Large the opinion seems to be going the other way and I am wondering if I should have ordered a large. Obviously the Ibis is an expensive bike and I do not want to make an expensive error. Again I am 6'2" 200lbs and 34" inseam riding mainly fast tight forest trails with some technical sections And with no stock here there is no getting a proper fitting maybe Ibis would like to send me two demo bikes so that I can help them decide this argument??

  18. #18
    mtbr member
    Reputation:
    Join Date
    Nov 2007
    Posts
    15
    Still reading... still confused....
    Now I have another question...
    I currently own a 2006 Scott Scale 40 Large and I use a 400mm seat post and it's inserted up to the minimum insertion limitation mark meaning that if I get a Large Mojo SL and for some reason (maybe the geometry) I have to move up a little how could I do that ?
    I still don't understand how a 6'2" & 34"+ inseam (91cm (35") inseam for me) can fit on the seat post ????
    help me out
    (HAPPY NEW YEAR)

  19. #19
    mtbr member
    Reputation:
    Join Date
    Sep 2007
    Posts
    33
    This thread make me nervous... I put in my order for an XL based on the frame measurements matching my old stump jumper XL. I am 6' 1" which is short enough that Tom here would likely recommend that I have a large. My inseam is 36.5" which together with a long arm length is the reason I was put on the XL in the first place.

    I questioned the decision when my bike shop put me on the stumpy but after riding for a while the bike seemed to be a good fit. My frame is supposed to be in the first part of January (unlikely in my opinion) so the time is short if there is any time at all for me to make a switch....

  20. #20
    mtbr member
    Reputation: Tall Tom's Avatar
    Join Date
    Oct 2005
    Posts
    87
    Quote Originally Posted by jminn8086
    I find this thread very helpful and timely! I just put a deposit on a new Mojo SL and need to confirm sizing. I'm 5 foot 10 inches tall with a 32 inch inseam and typically fall in between sizes for most manufacturers ... e.g. Santa Cruz. I currently have a medium Intense 5.5 (medium) with a 4.25" stem and straight seatpost. This setup works for me, but does put more weight on the front of the bike on steep descents.

    I've received conflicting feedback on whether I should go with a Large and shorter stem (e.g. 90 mm) or a medium with a 110 mm. I do not want to use a seatback seatpost. I would appreciate any further insight into this as I decide on frame size for a complete SL. Riding conditions where I ride include XC, AM and some pretty steep climbs and descents. I know I can make either work by fiddling with the seat adjustment and stem length, but I want to get this right in terms of design and bike geometry.

    So, Tall Tom, if you're still on the board, let me know what Ibis would recommend. I need to lock this down Wednesday this week.



    Thanks!
    Hello jiminn8086,
    Hopefully this post reaches you in time. I didn't see your question until this morning - occassionally the Ibis guys take a day off!
    Anyway, based upon the information you've given me I would recommend that you go with the Large frame. The Mojo already has a fairly short rear end, and going with a seat post with a lot of offset post can create an excessive rear weight bias. I think the Large with a 90 mm stem that you described would give you a good result.
    To all of the folks on this thread who are feeling confused, a couple of notes:
    - First, many of our dealers have demo bikes available for you to test ride. Despite all this discussion, actually riding the bike may be the best way to find the right size. Note, many dealers will charge you a fee to ride one of the demo bikes to cover maintainance, but most will also credit this fee toward the cost of purchasing a bike. A list of dealers with demo bikes is listed on the Ibis website.
    - Second, there's only so much that we can figure out through postings. Meeting with your LBS to discuss fitting is highly recommended with one or two caveats.
    As I mentioned in one of my previous posts, there is a trend towards using short stems on bikes right now that ignores the rest of the bikes geometry. Don't be afraid to use a 100 or 110 mm stem to fit the bike properly. That is, if going with the smaller of two frame sizes means using a 100 or a 110 mm stem than that will probably be the best size for you. On larger frames (LRG or XL) going with a 120 or even a 130 mm stem is fine too. Due to the prevailing trends your LBS may try to steer you towards a short stem set up which is not always the best option.
    Also, the only advice that I can give you is based upon our experience and perspective on bike set up. It is not infallible. Depending on your personal preferences, and the area that you ride in there can be a lot of different ways to set up your bike that will work. I've been riding mountain bikes for over 20 years now and the way I set my bikes up then is far different than what I do now. So make your best guess and adjust accordingly until you find best set up for you.
    Happy New Year Everyone!

  21. #21
    mtbr member
    Reputation:
    Join Date
    Dec 2007
    Posts
    32
    I went in to the dealer the other day and had a sit on a large again, given the difference is only about 1/8 of an inch on the top tube between the L and XL, I went with an XL with a 90mm stem, the guy at the shop is 6ft and rides a large. It does seem we are getting very stressed over less than a inch.

  22. #22
    mtbr member
    Reputation: Portti's Avatar
    Join Date
    Jan 2004
    Posts
    219
    Thanks for the advice Tom!

    I've just placed an order for a XL size Mojo SL frame.

    Quote Originally Posted by Tall Tom
    Hello Portti,

    Tom from Ibis posting again. At 6'3" you're right where I begin recommending an XL. ...
    Pertti
    Lahti, Finland
    MC Kramppi

  23. #23
    mtbr member
    Reputation:
    Join Date
    Apr 2007
    Posts
    174
    I have the chance to buy a well priced 2nd hand mojo, size M, i´m 170cm, 78cm inseam so my size shoud be 16", the mojo M equals a 17", what do you think?it will do? thanks

  24. #24
    MountainGoat aka OldGoat
    Reputation: pachaven's Avatar
    Join Date
    Dec 2005
    Posts
    764
    SAS2, I am 5'7" with a 30" inseam and I bought a used Mojo in size M and I could not be happier. You and I are almost the same size. I think you should do it. I now run a 90mm stem and 170mm cranks.
    Vote with your feet.
    No bike is perfect!

  25. #25
    mtbr member
    Reputation:
    Join Date
    Nov 2007
    Posts
    7

    For Tom to Answer

    As I started this post and have an XL on order on the advice of the Australian Distributor it appears that Tom is advising that I get a L? I am 6'1" with 34" inseam. Does not bike wheelbase factor into this equation as well? The previous bike that I have enjoyed riding is a Large Cannondale Rush which has a 69 degree head angle and a wheelbase of 1131, chainstay of 422, Top tube of 625. These measurements would seem similar to the XL Mojo. The nearest Mojo to me is a seven hour drive (one way) so it is hard to test ride one as per your other advice. Australia is meant to get its next shipment in three weeks so I could still change to a Large.....

Page 1 of 3 1 2 3 LastLast

Posting Permissions

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