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  1. #1
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    Mojo in a comparison test on the German Bike magazine

    The latest issue (01/2008) of the German Bike magazine arrived today. The magazine included a comparison test which included Ibis Mojo.

    The bikes tested were mostly German brands but the there were others too. Most bikes had approx. 120 mm of travel in the rear so the Mojo had a little bit longer travel than the others in the test.

    The tested bikes and their total point scores were:

    Specialized Stumpjumper Pro 125,75 (Super)
    Scott Genius MC 10 125,25 (Super)
    Ghost AMR Lector 9500 122,25 (Very Good)
    Felt Virtue Team 118,25 (Very Good)
    Rotwild R.GT2 Pro 116,75 (Very Good)
    Trek Fuel EX 9.5 117 (Very Good)
    Simplon Lexx Tra 116,25 (Very Good)
    Canyon Spectral 114,75 (Very Good)
    Gary Fisher Hifi Carbon Pro 113,25 (Very Good)
    Ibis Mojo (with XT parts) 109,5 (Good)

    The magazine also gives separate scores for the frame only and the Mojo was third from the last on this comparison.

    The actual weight of the Mojo (19") was 11.75 kg without pedals. The weight of the frame and shock was 2,653 g.

    In conclusion the magazine said that the Mojo is the individual choice. They say that the suspension works very well but the biggest weakness is the low stiffness of the frame. They measure the stiffness in two measurements ("bottom bracket stiffness" and "head tube stiffness") and the Mojo was by far the weakest. They mention that it is good for the flowing Californian trails but the lack of stiffness is more evident in the rocky European trails.


    The Mojo is one option when the time comes to replace my current ride (Rocky Mountain ETSX-Team) and one thing that worries me the most with the Mojo is this alleged stiffness problem. I have no chance to test ride the Mojo since there is no importer here in Finland so I have to rely on written reports and other people's experiences.

    I've read the recent heated discussion in relation to the stiffness of the rear end of the Mojo in this forum and I don't want to star another flame war. However I would really like hear more of the people's opinions in relation the stiffness of the frame.

    -Most owners seems to be happy with the stiffness but are there actual owners who feel that the frame is not very good in that respect?
    - Are there owners who usually ride in singletracks in conditions with lots of small rocks and roots? Can you notice the flex in these conditions?
    Pertti
    Lahti, Finland
    MC Kramppi

  2. #2
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    Well, that's disappointing, given that my SL is expected here next week. Have any of the US mags had the Mojo in any comparison tests? My wife rides a HIFi Pro, and that finished above the Mojo.

  3. #3
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    Quote Originally Posted by daryder
    Well, that's disappointing, given that my SL is expected here next week. Have any of the US mags had the Mojo in any comparison tests? My wife rides a HIFi Pro, and that finished above the Mojo.
    You can read lots of comparison tests on the Ibis site: http://www.ibiscycles.com/mountain/mojo/press/

    All the reviews I have read are glowing comparisons but I don't think I have read one that did specific measurement tests on flex.

    I know that for me as I ride my mojo in the colorado rockies and moab I don't notice flex issues - but I don't have a great point of comparison having never spent time on some of the acknowledged "inflexibles" out there. Bikes are about compromise, but the mojo seems the closest to perfection available.

  4. #4
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    The articles on the Ibis site are certainly glowing, but I didn't see any that are actually comparison tests. I'll check again. I'd sure like to read a translation of the German article. It sounds like they might have have put too much emphasis on flex-testing and not enough on how the bikes actually ride. Hard to tell, though, without the article. Not to mention that I wouldn't be able to read it. Can you help us out, Portti? Thanks.

  5. #5
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    Hi-Fi Pro

    What Mountain Bike recently reviewed the Hi-Fi Pro and came to the conclusion that it was one of the least stiff, most flexible frames they've ever ridden. They specifically mentioned an incident where they managed to get the chain to "ghost shift" across the cassette due to frame flex when hammering the bike hard. They said it was fast handling and light-weight, with somewhat twitchy handling, but gave it the thumbs up overall.

    I've not ridden the Hi-Fi Pro, but the Mojo felt plenty stiff on my test ride. I'm going to be waiting a while longer for my Mojo SL, at which point I'll be happy to provide you with a more complete analysis :-)

    - Matt

  6. #6
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    zzsean:

    Thanks for the feedback.

    daryder:

    I wouldn't worry too much about the test on the Bike magazine. I think that most likely the Mojo is a great bike and you'll love it.

    The article doesn't overemphasize the flex issue and it is just one of the many areas which they test. It's just something the Mojo was not very good at and that's why I would like hear actual owner's opinions on the matter.

    I think that I will not try to translate the article since it is very long and thorough and my German is far from perfect. One interesting thing on this test was that they have developed a new way of measuring the efficiency of the bike/suspension. They give points for "Wippen" (bobbing/anti-squat?) and "Pedalrückschlag" (pedal kick-back?) on each of the three front chainrings. The Mojo was very good on "Wippen" but not among the best in the "Pedalrückschlag".

    In my opinion the Bike magazine is one of the best mtb magazines since they are very informative and they do a lot of comparison tests on bikes and components. They complement the practical tests with measurements on the laboratory on their articles.
    Pertti
    Lahti, Finland
    MC Kramppi

  7. #7
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    [QUOTE=mattwatkins]What Mountain Bike recently reviewed the Hi-Fi Pro and came to the conclusion that it was one of the least stiff, most flexible frames they've ever ridden. /QUOTE]

    Also on the Bike magazine the Hi-Fi was second from the bottom on the stiffness tests.

    The stiffness to weight ratios on the tested bikes were (the absolute stiffness in brackets) (bigger number is better):

    Canyon 35,6 (91,7)
    Ghost 27,4 (70)
    Scott 26,8 (67,7)
    Specialized 25,4 (67,4)
    Simplon 24,6 (68,7)
    Rotwild 24,6 (58,8)
    Felt 23,4 (68)
    Trek 22,1 (58,7)
    Gary Fisher 20,6 (44,9)
    Ibis 16,3 (43,2)
    Pertti
    Lahti, Finland
    MC Kramppi

  8. #8
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    Smile

    germans are still mad about the war. mojo is the best bike I have ever ridden. My 1995 ellsworth absolute truth in its day was great also.
    .
    Mitch
    Boise
    nice snow rides lately

  9. #9
    Mojo0115
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    Quote Originally Posted by mtbmitch2
    germans are still mad about the war....
    heh, yeah... this is a stupid statement.

  10. #10
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    I see by the choices for "Very Good" the testers like suspensions that need very firm shock response to pedal OK but then produce a rather harsh and spiky ride in bumps.

    They probably set up the Mojo suspension as firm and shallow travel as those old-school monopivot types like.

    The Mojo is far from that, the Mojo is much more bump compliant and can still be pedaled with the highest efficiency and is easier to pedal and corner on bumpy trails than stiffly suspended bikes.

    The stiff suspensions just feel faster due to harsher feedback.

  11. #11
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    Just as I suspected: too much Pedalruckschlag. And it was designed by a toy designer. And a girl to boot.
    "Don't criticize what you can't understand."

  12. #12
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    Cool-blue Rhythm Beauty is in the eye of the beholder

    Interesting that they ranked the Specialzed in top place overall... The British "What Mountain Bike" Magazine have not given the very latest Specialized (S-Works Stumpjumper FSR) a very good initial write up, but seem to be prepared to give it a second chance. Apart from the fact that the own brand shock seized up during riding (locking the rear suspension out) they didn't seem to like the low bottom bracket height, claiming that it might have a problem with the pedals striking rocks. It wasn't a complete review, however.

    I suppose this just goes to show; much of beauty is in the eye of the beholder.

    Shame you can't arrange a test ride. Thought about taking a holiday and stopping off at a bike shop somewhere? When you're spending a large amount of your income on a bike, it might be worth the price of a plane ticket to spend some quality time with a few contenders before making your decision?

    - Matt

  13. #13
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    I cant believe that the HiFi is stiffer then the Mojo. Im sure they made a mistake. Yeah, I heard bout people say the Mojo rear end is not stiff, but usually its not noticeable. Maybe if you are a heavy rider, you should call Ibis and see what they can do for you.
    07 Giant Anthem 2 (Int'l Edition) | omartan.co.cc
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  14. #14
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    the ibis is way stiffer than my 05 truth. had to get used to snaking through rocks in a
    different way. You don't want a bike to stiff. In 1997 Honda changed to an aluminum
    frame that was way to stiff. the pros were getting thrown off the bikes a whole lot more.
    after 4 frame changes in 8 years, they finally got it right.
    Mitch

  15. #15
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    A real engineer

    Quote Originally Posted by Steve from JH
    Just as I suspected: too much Pedalruckschlag. And it was designed by a toy designer. And a girl to boot.
    Too bad it wasn't designed by a sales manager. It would be much stiffer.
    Don

  16. #16
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    A laboratory bench test is a very German way of testing.

    Also, judging products by results that do not reflect in real life use is very typical for this particular magazine.

    I believe the results are true, but I couldn't care less about them if the Mojo still rides better in real life than a Stumpjumper that was scored über-super. ( And that's what every other bike mag is saying )

  17. #17
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    Okay, here is a question bout stiffness. Aint a stiffer bike would get cracked up more easily then a less stiff bike? So I guess eventhough the Mojo is less stiff then the HiFi but a rider wont notice the flex, does it mean this is a good balance of stiffness to durability?
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    I would never even mention a Gary Fisher and an Ibis in the same breath, let alone compare them to eachother. It's like comparing apples to hemmorroids!
    Who cares what the German rags say! I knowe my Mojo handles better than a Stumpy for sure, because I have ridden both bikes, and I ride with a Stumpy owner all the time. He hates the chainsuck and his Specialized shock blew on him during the very last dirt ride up here this year, cutting our day short! Pissed me off too! Snowed the next day.
    And believe me when I say I don't slam Specialized. I own a Bart Brentjens Limited editionS-works M2 HT and it's my winter bike. And I love it

  19. #19
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    Thanks for the replys everybody. Here are some comments.

    derby

    The suspension on the Mojo was rated highly so the magazine did not see problems there. The bike category tested was "all-mountain light" and other bikes were equipped with slightly shorter suspension travel. Also the test criteria was designed for slightly shorter travel bikes.

    mattwatkins

    They did rate Specialized highly in this test. However the same issue of Bike had an article on some long term test bikes and Spezialized Enduro SL scored only 6 points (scale 1-10) which was the worst score on the article. The Specialized's own fork had broken 5 times and the rear shock once during the long term test.

    plussa

    The laboratory test on the Bike magazine can be over the top sometimes. However many times they do very interesting laboratory tests and they back up the lab tests with practical tests so it's a good mix of practice and theory.

    Bike and the German Mountain Bike are very good magazines in my opinion and by far more informative than any of the US magazines I've read. What MTB and especially the Mountain Bike Rider from the UK are also quite good magazines but I rate the Germans highly.


    Wheelhot:

    Based on the measurements the flexibility on the Mojo is way above the level where the flex should be noticable. My current bike is a Rocky Mountain ETSX-Team and every time an ETSX has been tested on either of the main German mtb-magazines (Bike and Mountain Bike) it has been among the most flexible bikes. I'm 77 kg and I do notice the flex in some circumstances but it doesn't bother me too much.

    According to the measurements the Mojo is even more flexible than ETSX so it should NOT be a very good compromise between stiffness and durability.

    However it seems like most owners don't notice any flex on the Mojo so I guess it is alright in this respect.



    Overall the Mojo missed the Very Good mark by only 0.5 points. Mojo scored bad points on the flexibility, warranty and missing bottle holder.

    Like I mentioned earlier the flex issue is the only thing that concern me based on this comparison test. I don't care about missing bottle holder and the three year warranty is a non-issue for me since it seems like the Mojo is durable and the customer service of the company is excellent.

    For those who are interested here are all of the scores for Mojo on the test. The scale is 1-6 and each test criteria are weighed (they weight is in brackets as well as the original German term):

    Uphill
    Geometry/handling (2) (Geometrie/Handling) 5 pts
    Suspension rear (1) (Federung hinten) 5 pts
    Suspension front (1) (Federung vorne) 5 pts
    Tyres (1) (Reifen) 4,5 pts
    Bottle holder (1) (Flaschenhalter) 1 pts
    Weight (2) (Gewicht) 5 pts
    Efficiency (2) (Effizienz) 4 pts
    Total uphill 43,5 pts

    Downhill
    Geometry/handling (2,5) (Geometrie/Handling) 4 pts
    Suspension rear (1,5) (Federung hinten) 5 pts
    Suspension front (1,5) (Federung vorne) 5 pts
    Ability to lower saddle (1)(Versenkbarkeit sattel) 6 pts
    Brakes (1,5) (Bremsen) 5 pts
    Tyres (1) (Reifen) 4,5 pts
    Stiffness (1) (Stefigheit) 1 pts
    Total downhill 44 pts

    Other
    Component selection (2) (Zusammenstellung Komponenten) 5 pts
    Optical things (1) (Optischer Eindruck) 5,5 pts
    Paint quality (1) (Lackqualität) 6 pts
    Warranty (1) (Garantie) 1 pts
    Total other 22

    Total (max 160) 109,5
    Pertti
    Lahti, Finland
    MC Kramppi

  20. #20
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    Wink

    One of the key benefits of composite materials, such as carbon fibre, is that they give designers and engineers the ability to put strength and stiffness in the places where they are needed. I have no doubt that in practice, this takes plenty of skill and an intimate knowledge of the material to achieve... Personally, I trust that the folk at Ibis know what they are doing. I have no idea how these tests were conducted, but I wouldn't be surprised if they don't translate into a particularly useful "real world" metric of the frame's behaviour and performance while riding. As somebody has already pointed out in this thread, this is a stereotypically teutonic approach to testing.

  21. #21
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    Thanks, Portti. I appreciate you passing this info along.

  22. #22
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    Flexy metal bikes are springy and reduces traction in corners. Flexy carbon fiber is damped and allow faster cornering with greater traction. There is no pedaling advantage to stiffer frames, only imagined.

    The sideways cornering flex in carbon fiber "issue" is the same as riders coming from hardtail to suspension thinking suspension is slower in climbing performance because it doesn't feel as firm.

    A flexy metal bike does have directional cornering issues due to being bouncy when leaned over.

    The mild flex in the Mojo is damped with no cornering side bounce, a performance advantage.
    Last edited by derby; 12-14-2007 at 12:30 PM.

  23. #23
    Elitest thrill junkie
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    Quote Originally Posted by derby
    Flexy metal bikes are springy and reduces traction in corners. Flexy carbon fiber is damped and allow faster cornering with greater traction. There is no pedaling advantage to stiffer frames, only imagined.

    The sideways cornering flex in carbon fiber "issue" is the same as riders coming from hardtail to suspension thinking suspension is slower in climbing performance because it doesn't feel as firm.

    A flexy metal bike does have directional cornering issues due to being bouncy when leaned over.

    The mild flex in the Mojo is damped with no cornering side bounce, a performance advantage.
    Come on now, you have a pretty good reputation. You're just making stuff up here. You know full well that excessive flex will induce binding, ill handling in the corners, and so on, and just because it's carbon fiber doesn't mean it's "damped". The new corvette Z06 has carbon fiber leaf springs. And because it's "damped" are you telling me that it doesn't need shock absorbers? You can do better than this.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  24. #24
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    Quote Originally Posted by Jayem
    Come on now, you have a pretty good reputation. You're just making stuff up here. You know full well that excessive flex will induce binding, ill handling in the corners, and so on, and just because it's carbon fiber doesn't mean it's "damped". The new corvette Z06 has carbon fiber leaf springs. And because it's "damped" are you telling me that it doesn't need shock absorbers? You can do better than this.
    Well the Mojo doesn’t have a lot of side flex in the first place. It is less than twice as much rear stay twist using the same efforts pulling and pushing the top of the rear wheel vs. the seat post compared to a walking-beam type new Turner Flux, Spot, or Trek Fuel (all the same in stiffness) I checked out in a LBS next to my now 1.5 year old Mojo. And no more than most 5 inch travel bikes when pushing the crankarm BB sideways with my foot. So there's not really a flex issue with the Mojo in the first place - except to a few nitwits who need sharp and spiky feedback.

    Since there is so little flex there would be no way to effect of some kind of additional damping beside the natural molecular level damping character of carbon fiber.

    So I stand by my theory that a little more side flex with naturally damping carbon fiber is better than less flex with springy metal.

    Corvettes still use a leaf spring across the rear? It was fiberglass 10 years ago. Nice falling rate design (not!) Anyone taking them to the track replaces with coilover.

    Glad to see you are interested in the Mojo, Jayem. It's a pretty amazing and versatile ride, especially with Push'd coil front and rear now. I demoed a 6Point at Interbike, it's got more pedal clearance and slacker handling, maybe more in line with your guys rides, same weight as a Nomad it pedals just as smooth and efficiently as the Mojo but even more plush. I couldn't make it to AZ this year. Hopefully next spring or fall.

  25. #25
    Elitest thrill junkie
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    Quote Originally Posted by derby
    Well the Mojo doesn’t have a lot of side flex in the first place. It is less than twice as much rear stay twist using the same efforts pulling and pushing the top of the rear wheel vs. the seat post compared to a walking-beam type new Turner Flux, Spot, or Trek Fuel (all the same in stiffness) I checked out in a LBS next to my now 1.5 year old Mojo. And no more than most 5 inch travel bikes when pushing the crankarm BB sideways with my foot. So there's not really a flex issue with the Mojo in the first place - except to a few nitwits who need sharp and spiky feedback.

    Since there is so little flex there would be no way to effect of some kind of additional damping beside the natural molecular level damping character of carbon fiber.

    So I stand by my theory that a little more side flex with naturally damping carbon fiber is better than less flex with springy metal.

    Corvettes still use a leaf spring across the rear? It was fiberglass 10 years ago. Nice falling rate design (not!) Anyone taking them to the track replaces with coilover.

    Glad to see you are interested in the Mojo, Jayem. It's a pretty amazing and versatile ride, especially with Push'd coil front and rear now. I demoed a 6Point at Interbike, it's got more pedal clearance and slacker handling, maybe more in line with your guys rides, same weight as a Nomad it pedals just as smooth and efficiently as the Mojo but even more plush. I couldn't make it to AZ this year. Hopefully next spring or fall.
    Come on now, people don't replace the springs on the Z06 as soon a they track it, because it basically eats everything else, even lots of highly modified cars. It's pretty amazing performance for the $.

    In any case, your theory is unfounted, you could say the same about any material that flexes, because you'll NEVER get 100% of the energy back, and then EVERY material is "damped" basically. That's what your saying, and it's pretty rediculous.

    In any case, lateral stiffness is very important, I've been on plenty of bikes where the rear suspension tended to bind more and the bike deflected as the suspension didn't do a very good job of absorbing in the direction that it was supposed to. I've ridden my foes quite a bit and I've ridden lots of other bikes. Lots of bikes even feel pretty stiff out of the box, but give them a year for their bearings to wear down and they get to feel pretty sloppy.
    "It's only when you stand over it, you know, when you physically stand over the bike, that then you say 'hey, I don't have much stand over height', you know"-T. Ellsworth

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  26. #26
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    Quote Originally Posted by Jayem
    Come on now, people don't replace the springs on the Z06 as soon a they track it, because it basically eats everything else, even lots of highly modified cars. It's pretty amazing performance for the $.

    In any case, your theory is unfounted, you could say the same about any material that flexes, because you'll NEVER get 100% of the energy back, and then EVERY material is "damped" basically. That's what your saying, and it's pretty rediculous.

    In any case, lateral stiffness is very important, I've been on plenty of bikes where the rear suspension tended to bind more and the bike deflected as the suspension didn't do a very good job of absorbing in the direction that it was supposed to. I've ridden my foes quite a bit and I've ridden lots of other bikes. Lots of bikes even feel pretty stiff out of the box, but give them a year for their bearings to wear down and they get to feel pretty sloppy.
    I imagine the Vette rear spring has improved much in ten years, and they can mold a rising rate leaf spring.

    You had mentioned bearing slop causing handling issues. I’m not talking about worn or loose bearings or loose pivots. My Mojo ridden under my 200+ lb weight has developed no loose bearings or pivot bolts in 1.5 years of riding 2 – 5 times per week doing no maintenance. I think some of the longevity of the bearings is due to the (non-perceivable when riding) small amount of twisting flex compliance in the rear swingarm

    The Mojo has zero perceivable flex compliance in the vertical line or chain-line of direction. The mild lateral flex pushing at the BB is about the same as most “stiff” bikes. The only perceivable flex test is pushing and pulling the top of the rear wheel and seat post sideways in opposing directions.

    While riding this produces a very small amount of compliance when deflecting off the sides of rocks at speed and when leaned over cornering over rough surface.

    This is lateral suspension. Damped suspension is faster and produces better grip than rigidly mounted wheels.

    Carbon Fiber being a material with molecular level damping quality reduces the otherwise bouncy deflections caused by the balloon tires hitting obstacles in these rough conditions. It follows that stiffer and springy metal frames would not dampen the same tire bounce as well.

    At the relatively low speeds mountain bikes are ridden some mild side flex is an advantage for directional control, grip in corners, and speed. All motocross and race street bikes have side flex suited for their heavier weights and higher speeds.

    Trying to convince someone that mildly damped suspension is better than springy more rigid suspension is useless without riding it. The Mojo ride is awesome, the finest in its travel range of the dozens I’ve tried, by a large margin. The mild lateral suspenion is a minor but possibly significant part of the improved quality. The Mkiii in ’07 is nearly the same suspension and frame geometry and travel, yet feels a bit less smooth riding compared with the Mojo, perhaps the minor extra frame weight and ½ inch less travel being the biggest difference.

    I can see that more rigid, firmer damped, and shorter travel may have appealed to the German testers who only ride high mountain rock gravel, loamy tree decay, and sand. On the smoother trails sand or loam creates damping and compliance so firmer less compliant suspension may have more feedback for the rider to react to. The Mojo’s dw-Link is so efficient that riders used to pedaling harder to climb and accelerate on loose trails may spin the rear tire by over powering the conditions on the much more power delivery efficient dw-Link. And when bashing up rock steps when pedaling, the more common less efficient suspension bikes delay pedaling feedback into off-directional oscillations of squat and bob and losses of traction; but with such high traction on large rock steps the traction loss is not an issue and less pedaling power would be more comforting, like having noticeably flexible cranks would be more comfortable.

    It does take a little experience to apply power with finesse to conserve energy not needed as constantly when riding a much more efficient pedaling dw-Link. Less power is easier to control. A rider will adapt naturally to use less power when harder power input is less controllable. The net benefit is ability for the same rider to ride faster where it’s easier, and ride longer overall with the same energy.

    I seen later posts about the German test that the Mojo just missed the Top tier of “Very Good” and it was due to the bench test measurements of flex and pedal feedback, which apparently are misinterpreted, just as some misinterpret the Linkage program’s “Kick-back” figures without considering the dynamic effects of squat at bob to pedal kick-back. All ride time reviews place the Mojo at the very top as the best bike.

  27. #27
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    This is lateral suspension. Damped suspension is faster and produces better grip than rigidly mounted wheels.

    Carbon Fiber being a material with molecular level damping quality reduces the otherwise bouncy deflections caused by the balloon tires hitting obstacles in these rough conditions. It follows that stiffer and springy metal frames would not dampen the same tire bounce as well.

    At the relatively low speeds mountain bikes are ridden some mild side flex is an advantage for directional control, grip in corners, and speed. All motocross and race street bikes have side flex suited for their heavier weights and higher speeds.
    Well said. I'm really suprised by the review. I guess the perceived lateral deflection is different when riding as opposed to using a testing machine.
    All the bikes on the test except Simplon and Felt had carbon front triangle. This means that the weak score for Mojo on the sideways flexibility measurement can't be explained by saying that it is because of the characteristics of the material used on the frame.
    A full carbon rear triangle rides very differently and transmits differently than a alum rear triangle even mounted to a carbon front. (That's the main reason I'm not a big fan of Trek Fuel redesign.) Alum rear triangles are a cheap easy out (easier on warranty issues) but they TOTALLY CHANGE THE RIDE.

    I want to read the full transcript of the article, not just "it said etc." since this has turned into such a big thread whom-ever started the post, I would appreciate a translation of the review posted here.
    Thanks
    Last edited by glovemtb; 12-15-2007 at 02:50 PM.

  28. #28
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    Thanks for your input Derby, I've read some of your earlier posts on this forum and I value your opinion.

    I would like to clarify few things regarding the comparison test on the Bike magazine.

    - The Mojo scored good points for suspension. The measured pedal kick-back influenced the efficiency score (4 pts for Mojo) and it was NOT the reason for Mojo not receiving Very Good status.

    I'm not sure how valid the way they measure the suspension efficiency is in real life. They have article where they explain their testing methods on the same issue of the magazine but my understanding of the german language and suspension theory is not good enough to be able to judge how valid these measurements are.

    - All the bikes on the test except Simplon and Felt had carbon front triangle. This means that the weak score for Mojo on the sideways flexibility measurement can't be explained by saying that it is because of the characteristics of the material used on the frame.

    They measure the flexibility/stiffness from two different points. Firstly they attach the frame to the test bench and then they apply sideways force to the bottom bracket area and measure the sideways flexibility. Secondly they do a similar test by applying sideways force to the head tube.

    I think that these measurements might have something to do with real life. What do other people think? Are these valid measurements?

    By the way they test the bikes around Lake Garda in Italy where the trails are excellent.
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  29. #29
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    Quote Originally Posted by Portti
    Thanks for your input Derby, I've read some of your earlier posts on this forum and I value your opinion.

    I would like to clarify few things regarding the comparison test on the Bike magazine.

    - The Mojo scored good points for suspension. The measured pedal kick-back influenced the efficiency score (4 pts for Mojo) and it was NOT the reason for Mojo not receiving Very Good status.

    By the way they test the bikes around Lake Garda in Italy where the trails are excellent.
    If they measured that there is any kickback on the Mojo, then their scales are incomplete and misinterpreted. Anyone who has ridden any dw-Link bike design knows there is no kickback sensation when riding in any gear over any rough or smooth trail situation. Even the most critical over sensitive review recently in Iron Horse by "le-buzz" admits there is no kickback, only feedback he is not comfortable with (from a poor suspension tune), which is not the same as kickback. There is very smooth pedal feedback with the Mojo, the pedals slow or stop when the bike slows or stops rolling forward. There is never backpedal unless the rider not moving forward while bouncing the suspension, such as doing a trackstand and bouncing up and down leaving the ground.

    It sounds like the Germans have a limited set of factors to measure kickback, missing wheel speed, acceleration speed change, and climbing and acceleration squat.

    For example if a bike has a locked front wheel (not rolling) compression crank rotation "kickback" of 10 degrees when compressing 1 inch. And another bike has only 5 degrees "kickback" with the same 1 inch compression when not rolling. But when moving and pedaling and hitting a bump the first bike compresses from the bump 1 inch as the rider climbs and the second bike also compresses 1 inch from the bump but also squats back a further 1 inch from the rider weight shift, then the "kickback" is the same while riding. The feedback slow the pedals less upon initial bump hit for the second bike due to slow squat reaction. but T second bike’s delay climbing the increased incline due to the increased squat weight shift further behind the pedals and added wallow will add up to greater effort just to maintain balance. The feedback is spread out on the less efficient second squatty pedaling bike and feels softer in the pedals, but the rider feedback is spread into wallow, bob, traction loss, and imbalance, netting slower climbing using more energy. And both bikes have the same amount of kickback (backpedal or pedal slowing) when hitting and climbing the bump. The resulting wallow oscillations of the second bike dissipate energy too.

    So where do you want your feedback? I want feedback that is consistent and balanced with the trail to sense it immediately, not dissipated by flailing around in wallow and weight imbalance, or insulated and burned away in a firmer damper's increased heat.

    The Mojo very smoothly balances suspension in 3 dimensions, and has smooth pedaling feedback and easy effort, while riding noticeably better than any other design I've ridden. I must ride longer or climb steeper on the Mojo to get exhausted. For me the ride is far more interesting than bench tests. Bench tests should not be used or just heuristically weighted minimally in bike evaluations. Bench tests are trivia.

    I hope I can get to ride around Lake Garda in Italy someday, it looks so spectacular in pictures!

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    This is such a big thread about an article no one has seen here. Can who ever read the article please post it. You can simply run it through an on-line translator. Really, at this point I would like to read the real review.

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    Wow, derby you really had out done yourself. Your replies are sick! (compliment). Good job and have you ever wondered to work in Ibis Q & A department?
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    I've stayed at lake Garda and ridden a hire bike into the surrounding hills. It was a really beautiful place to visit; I'd love to go back with my own bike one day...

    - Matt

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    ghawk:

    I don't think the article can be found online anywhere. It is just on the paper copy of the magazine.

    derby:

    I do believe that the suspension of the Mojo works very well, I have no issues with that.

    The sideway stiffness issue was the only thing that has worried me. However the practical experience from the users seems to indicate that this is a non-issue in practice. Or does somebody have contradictory evidence on that issue?


    The Lake Garda area is really beautiful, I've been there with my own bike and the area is great for biking holiday. It is also good area for many other activities and nice for the family also.
    Pertti
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    Just a little update on the test methods of the Bike magazine.

    The software they use for analyzing the suspension efficiency is called Igorion.

    http://www.igorion.com/

    Search on the mtbr.com for Igorion did reveal some hits but I've not had time to read them through.

    Derby & others: Are you familiar with the software? How would you rate the software?
    Pertti
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  35. #35
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    Quote Originally Posted by Portti
    Just a little update on the test methods of the Bike magazine.

    The software they use for analyzing the suspension efficiency is called Igorion.

    http://www.igorion.com/

    Search on the mtbr.com for Igorion did reveal some hits but I've not had time to read them through.

    Derby & others: Are you familiar with the software? How would you rate the software?
    I'm familar. I wouldn't base any realistic performance claims or comparisons on the software. I think its a nice tool for making pretty pictures and plotting axle paths, but that information alone isn't all too useful.

    At one place on the site they say: " one of the key features of fs-kinematics is the calculation of forces on the rear axle, as they oscillate with every pedal stroke. this makes it very easy to anticipate (anti)squat behaviour of existing or new designs. only available in the PRO-versions."

    This should be a tipoff to anyone interested in the software, as anti squat mangnitude is irrespective of force oscillation at the rear axle. A certain amount of force can only accelerate a vehicle an amount directly corresponding with the amount of force generated. Therefore, anti squat and vehicle acceleration are directly tied to and proportional to force at the rear axle.

    In other words, the above "feature" described in the software, although interesting, is not useful for calculating anti squat.
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  36. #36
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    Quote Originally Posted by _dw
    I'm familar. I wouldn't base any realistic performance claims or comparisons on the software. I think its a nice tool for making pretty pictures and plotting axle paths, but that information alone isn't all too useful.

    At one place on the site they say: " one of the key features of fs-kinematics is the calculation of forces on the rear axle, as they oscillate with every pedal stroke. this makes it very easy to anticipate (anti)squat behaviour of existing or new designs. only available in the PRO-versions."

    This should be a tipoff to anyone interested in the software, as anti squat mangnitude is irrespective of force oscillation at the rear axle. A certain amount of force can only accelerate a vehicle an amount directly corresponding with the amount of force generated. Therefore, anti squat and vehicle acceleration are directly tied to and proportional to force at the rear axle.

    In other words, the above "feature" described in the software, although interesting, is not useful for calculating anti squat.
    I haven spent much time with Igor’s software, I think you have to subscribe to it. I bet he’s got a few more advanced calculations than Gergely’s Linkage for the kinematics and “kick-back”. But unless it included rolling bump hit kinematics it would be incomplete about anti-squat effects.

    Anti-squat is reactive with the momentary position of the whole bike geometry including suspension, CM, and ground line between the contact patches.

    When hitting a sharp bump the ground-line between the contact patches instantly changes as the contact patch is suddenly positioned forward and higher on the wheel. Most suspension bikes have little change in anti-squat rate when suspension compression on level ground, the anti-squat rate will rise suddenly and only drop upon passing the bump.

    This sudden rise in ani-squat must feedback in the seat or the pedals. Low in ant-squat suspension geometry hides and diffuses the feedback in willowy and squatty handling, and slow pedal acceleration response. High anti-squat that is efficient accelerating on smooth flat surface produces more noticeable feedback hitting bumps.

    The dw-link reduces anti-squat rate rapidly from a moderately high rate with efficient acceleration to a much lower moderately average rate in mid travel having low bump feedback. The acceleration efficiency and stability is not sacrificed while the bump feedback is low with dw-Link to a degree never close to being matched with previous suspension designs.

  37. #37
    _dw
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    Quote Originally Posted by derby
    I haven spent much time with Igor’s software, I think you have to subscribe to it. I bet he’s got a few more advanced calculations than Gergely’s Linkage for the kinematics and “kick-back”. But unless it included rolling bump hit kinematics it would be incomplete about anti-squat effects.

    Anti-squat is reactive with the momentary position of the whole bike geometry including suspension, CM, and ground line between the contact patches.

    When hitting a sharp bump the ground-line between the contact patches instantly changes as the contact patch is suddenly positioned forward and higher on the wheel. Most suspension bikes have little change in anti-squat rate when suspension compression on level ground, the anti-squat rate will rise suddenly and only drop upon passing the bump.

    This sudden rise in ani-squat must feedback in the seat or the pedals. Low in ant-squat suspension geometry hides and diffuses the feedback in willowy and squatty handling, and slow pedal acceleration response. High anti-squat that is efficient accelerating on smooth flat surface produces more noticeable feedback hitting bumps.

    The dw-link reduces anti-squat rate rapidly from a moderately high rate with efficient acceleration to a much lower moderately average rate in mid travel having low bump feedback. The acceleration efficiency and stability is not sacrificed while the bump feedback is low with dw-Link to a degree never close to being matched with previous suspension designs.
    Ray, if you map out a dw-link (or many other bikes) and look at the change in contact patch as the wheel hits a bump you'll notice that there is little change in anti-squat due to the contact patch shifting. This is because the contact patch shifts upward as well as forward. This is an area that I've been talking about since back in the days when Dougal was on MTBR, and something that I brought up to Dougal back in 2000 or so to help him refine some of his early work. I wonder what happened to that guy, he was pretty sharp.. This is also an area that is definitely considered in all dw-link suspension designs during the development process.

    Anti squat magnitude is not directly related to the perception of pedal feedback.
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  38. #38
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    Quote Originally Posted by derby
    If they measured that there is any kickback on the Mojo, then their scales are incomplete and misinterpreted.
    What ? if anybody, no matter how scientifically based, measures any pedal feedback on the Mojo, they're just wrong ? I've never seen someone thats willing to go through such weird contortions of logic to deny reality than you.
    It's too bad, because you otherwise have a lot of good things to say, I just wish
    you were a little more honest about pedal feedback.

    Quote Originally Posted by derby
    Anyone who has ridden any dw-Link bike design knows there is no kickback sensation when riding in any gear over any rough or smooth trail situation. Even the most critical over sensitive review recently in Iron Horse by "le-buzz" admits there is no kickback, only feedback he is not comfortable with (from a poor suspension tune), which is not the same as kickback. There is very smooth pedal feedback with the Mojo, the pedals slow or stop when the bike slows or stops rolling forward. There is never backpedal unless the rider not moving forward while bouncing the suspension, such as doing a trackstand and bouncing up and down leaving the ground.
    No, not at all. While the pedal feedback sensation was very mild most of the
    time, when it counted most, they're was noticeable pedal jerk, caused by the fluctuating chain tension, when climbing rocky jagged sections in the
    granny riding towards the end of the ride. The end result of this was
    unfortunately my knees were acting as shock absorbers.
    Pedal feedback in the rough also reduces your momentum, in the right kind of
    conditions this can actually result in less pedaling efficiency.
    For the record, the suspension was tunes at 25 % sag during the most technical
    part of the ride, slightly less before that, which is not out of line with what
    _dw recommends (25 - 30%). This is discussed ad-nauseum on the other
    thread, I'm not going to rehash it here.
    But just simply arguing that everybody that notices pedal feedback has an improper tune, which is what you seem to be insinuating about the German test, sounds like kind of weak.

    [QUOTE=derby]
    It sounds like the Germans have a limited set of factors to measure kickback, missing wheel speed, acceleration speed change, and climbing and acceleration squat.

    For example if a bike has a locked front wheel (not rolling) compression crank rotation "kickback" of 10 degrees when compressing 1 inch. And another bike has only 5 degrees "kickback" with the same 1 inch compression when not rolling. But when moving and pedaling and hitting a bump the first bike compresses from the bump 1 inch as the rider climbs and the second bike also compresses 1 inch from the bump but also squats back a further 1 inch from the rider weight shift, then the "kickback" is the same while riding. The feedback slow the pedals less upon initial bump hit for the second bike due to slow squat reaction. but T second bike’s delay climbing the increased incline due to the increased squat weight shift further behind the pedals and added wallow will add up to greater effort just to maintain balance. The feedback is spread out on the less efficient second squatty pedaling bike and feels softer in the pedals, but the rider feedback is spread into wallow, bob, traction loss, and imbalance, netting slower climbing using more energy. And both bikes have the same amount of kickback (backpedal or pedal slowing) when hitting and climbing the bump. The resulting wallow oscillations of the second bike dissipate energy too.
    [QUOTE]

    This is total nonsense. You dont use suspension squat is to measure kickback.
    The dw-link bikes are nice and generally have a very positive feel, except in
    the In more extreme where pedal cadence issues become more prominant.
    It is possible to still have a reasonably efficient bike without so much antisquat,
    that has totally active traction all the time without any pedaling irregularities.

  39. #39
    _dw
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    LeBUzz,

    What bicycle company are you affiliated with?

    I find many of your assumptions, which you present as if they were somehow factual, to be totally ridiculous. Perhaps you should preface your opinions with something that suggests that they are opinions based on no actual analysis rather than presenting them as fact..

    Lets face it, a few months ago you were on this very forum asking me to explain key elements of suspension dynamics to you. I didn't explain it all, and I don't think that you're any type of "expert" quite yet. You shouldn't be pretending to be one, even if you did stay at a holiday inn express last night.
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    Duplicate popst, my bad. See below
    Last edited by le_buzz; 12-19-2007 at 12:30 PM.

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    Quote Originally Posted by _dw
    LeBUzz,

    I find many of your assumptions, which you present as if they were somehow factual, to be totally ridiculous.
    Such as ?

    Quote Originally Posted by _dw
    Perhaps you should preface your opinions with something that suggests that they are opinions based on no actual analysis rather than presenting them as fact..
    Yes, they are my opinions, but backed up by riding experience of different
    suspensions. I am not an expert, nor do I pretend to be one, but my opinions
    about pedal feedback are based on a lot of research by experts, other engineers
    who have done tests as well as what I have experienced on the ground, which
    has generally backed up what they have said.
    You seem to have no problem with some of derby's opinions, which are 'not
    based on fact' either.

    Quote Originally Posted by _dw
    Lets face it, a few months ago you were on this very forum asking me to explain key elements of suspension dynamics to you. I didn't explain it all, and I don't think that you're any type of "expert" quite yet. You shouldn't be pretending to be one, even if you did stay at a holiday inn express last night.
    _dw, I respect your engineering expertise, but you are not the only
    expert(engineer) that has opinions about this. Others with equal qualifications to yourself
    have different opinions. I have to wonder whether some of your opinions, which
    you state as fact without giving good reasons, are a little biased since you
    are also marketing your suspension design.
    When I have asked you to quantify some of your statements, ie 'x is impossible',
    on the other thread, my questions went unanswered. I've noticed this in past too,
    you make assertion x, but often give an incomplete explanation as to the
    why and the how. To simply discount what I say as worthless because I dont
    work for a bicycle company seems to be a bit disingenuous because you
    evidently dont want to spend the time to get into details or give explanations
    for what you say. As I said on the other thread, I'm all ears if you're willing to
    do that. So far you haven't been, so I have to regard a lot of your assertions as opinions also.
    Last edited by le_buzz; 12-19-2007 at 12:27 PM.

  42. #42
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    > Yes, they are my opinions, but backed up by riding experience of different
    suspensions. I am not an expert, nor do I pretend to be one, but my opinions
    about pedal feedback are based on a lot of research by experts, other engineers
    who have done tests as well as what I have experienced on the ground, which
    has generally backed up what they have said.

    Of course, people are free to express their opinions (but if you're a critic of the Russian president, it is probably wise to keep them to yourself). Thanks to the Internet, people have many new and exciting ways to share their opinions with each other. I suppose this could be called progress, but personally, I prefer the term FLAME WAR ;-)

    I suppose that ultimately, technical discussions require a technical argument. Talking in a loud voice about fairies at the bottom of the garden doesn't actually make it any more likely that they exist. The good news is, I don't think you'll find many riders hanging around on these forums that really care too much about the hype surrounding DW-Link suspension designs, although there are plenty of people (like myself) curious enough to listen to technical discussions about the merits of one design versus another. At the end of the day, it's probably not worth getting too excited about these things, though.

    Ride more, work less.

    Amen.

    - Matt

  43. #43
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    Quote Originally Posted by _dw
    Ray, if you map out a dw-link (or many other bikes) and look at the change in contact patch as the wheel hits a bump you'll notice that there is little change in anti-squat due to the contact patch shifting. This is because the contact patch shifts upward as well as forward. This is an area that I've been talking about since back in the days when Dougal was on MTBR, and something that I brought up to Dougal back in 2000 or so to help him refine some of his early work. I wonder what happened to that guy, he was pretty sharp.. This is also an area that is definitely considered in all dw-link suspension designs during the development process.

    Anti squat magnitude is not directly related to the perception of pedal feedback.
    I had it backwards (my dyslexia flaring up again!). A rear tire hitting a sharp bump would suddenly lower anti-squat rate, but I suppose it would only be suddenly a few percent lower in rate which would explain why you say anti-squat rate doesn’t affect feedback significantly.

    So it leaves acceleration or fluctuation in change of chain stay growth rate during compression travel that would be the significant pedal feedback sensation factor, not the amount it grows. Example: a Klein Mantra URT that has high rate of anti-squat does not have sharp pedal feedback. Thanks for the correction.

    Dougal got married and is working full time. Before he was married a few years ago he visited this area with his to-be fiancée and stayed a few days at my place. He's a very nice person and not anywhere as aggressive in person as he was on these forums. As far as I know he is still a firm believer in pivot-at-chainline produces no reactivity.

  44. #44
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    Quote Originally Posted by ibisrox
    my Mojo handles better than a Stumpy for sure, because I have ridden both bikes, and I ride with a Stumpy owner all the time.
    I have no doubt the Mojo handles very well but weather you like one bike over an other is a personal preference. Example, I prefer slacker head angles - even on my trail bikes but I have friends I ride with that like steeper HA's. Obviously we'll have different opinions when it comes to bike geo preference. Where/what you ride is also another important thing to consider.

    Quote Originally Posted by ibisrox
    He hates the chainsuck and his Specialized shock blew on him during the very last dirt ride up here this year, cutting our day short! Pissed me off too! Snowed the next day.
    sounds like his bike isn't setup properly...

  45. #45
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    Quote Originally Posted by mattwatkins
    Of course, people are free to express their opinions (but if you're a critic of the Russian president, it is probably wise to keep them to yourself). Thanks to the Internet, people have many new and exciting ways to share their opinions with each other. I suppose this could be called progress, but personally, I prefer the term FLAME WAR ;-)

    I suppose that ultimately, technical discussions require a technical argument. Talking in a loud voice about fairies at the bottom of the garden doesn't actually make it any more likely that they exist. The good news is, I don't think you'll find many riders hanging around on these forums that really care too much about the hype surrounding DW-Link suspension designs, although there are plenty of people (like myself) curious enough to listen to technical discussions about the merits of one design versus another. At the end of the day, it's probably not worth getting too excited about these things, though.

    Ride more, work less.

    Amen.

    - Matt
    A flame war this is indeed ... but who's talking loudly about fairies at the bottom of the garden, le_buzz or _dw? I find le-buzz's observations and methodology hardly scientifical, however, _dw hardly ever answers any technical questions in a satisfactory manner, seeming to skirt certain issues, and one must keep in mind his vested interest in the DW-link design.

    As far as I am concerned, each well implemented rear suspension design will have an edge over the others in certain trail conditions ... hopefully the bike one rides is the bike that suits his/her trail conditions which will make for a great ride and a happy rider.

    And that is my and president Putin's opinion!

  46. #46
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    Seat of the pants observation

    Quote Originally Posted by derby
    I imagine the Vette rear spring has improved much in ten years, and they can mold a rising rate leaf spring.

    You had mentioned bearing slop causing handling issues. I’m not talking about worn or loose bearings or loose pivots. My Mojo ridden under my 200+ lb weight has developed no loose bearings or pivot bolts in 1.5 years of riding 2 – 5 times per week doing no maintenance. I think some of the longevity of the bearings is due to the (non-perceivable when riding) small amount of twisting flex compliance in the rear swingarm

    The Mojo has zero perceivable flex compliance in the vertical line or chain-line of direction. The mild lateral flex pushing at the BB is about the same as most “stiff” bikes. The only perceivable flex test is pushing and pulling the top of the rear wheel and seat post sideways in opposing directions.

    While riding this produces a very small amount of compliance when deflecting off the sides of rocks at speed and when leaned over cornering over rough surface.

    This is lateral suspension. Damped suspension is faster and produces better grip than rigidly mounted wheels.

    Carbon Fiber being a material with molecular level damping quality reduces the otherwise bouncy deflections caused by the balloon tires hitting obstacles in these rough conditions. It follows that stiffer and springy metal frames would not dampen the same tire bounce as well.

    At the relatively low speeds mountain bikes are ridden some mild side flex is an advantage for directional control, grip in corners, and speed. All motocross and race street bikes have side flex suited for their heavier weights and higher speeds.

    Trying to convince someone that mildly damped suspension is better than springy more rigid suspension is useless without riding it. The Mojo ride is awesome, the finest in its travel range of the dozens I’ve tried, by a large margin. The mild lateral suspenion is a minor but possibly significant part of the improved quality. The Mkiii in ’07 is nearly the same suspension and frame geometry and travel, yet feels a bit less smooth riding compared with the Mojo, perhaps the minor extra frame weight and ½ inch less travel being the biggest difference.

    I can see that more rigid, firmer damped, and shorter travel may have appealed to the German testers who only ride high mountain rock gravel, loamy tree decay, and sand. On the smoother trails sand or loam creates damping and compliance so firmer less compliant suspension may have more feedback for the rider to react to. The Mojo’s dw-Link is so efficient that riders used to pedaling harder to climb and accelerate on loose trails may spin the rear tire by over powering the conditions on the much more power delivery efficient dw-Link. And when bashing up rock steps when pedaling, the more common less efficient suspension bikes delay pedaling feedback into off-directional oscillations of squat and bob and losses of traction; but with such high traction on large rock steps the traction loss is not an issue and less pedaling power would be more comforting, like having noticeably flexible cranks would be more comfortable.

    It does take a little experience to apply power with finesse to conserve energy not needed as constantly when riding a much more efficient pedaling dw-Link. Less power is easier to control. A rider will adapt naturally to use less power when harder power input is less controllable. The net benefit is ability for the same rider to ride faster where it’s easier, and ride longer overall with the same energy.

    I seen later posts about the German test that the Mojo just missed the Top tier of “Very Good” and it was due to the bench test measurements of flex and pedal feedback, which apparently are misinterpreted, just as some misinterpret the Linkage program’s “Kick-back” figures without considering the dynamic effects of squat at bob to pedal kick-back. All ride time reviews place the Mojo at the very top as the best bike.
    I think the suspension works very well compared to other suspensions. I've ridden most types. The lateral flex doesn't show up very much. I would say in the past, I have noticed it maybe 4 times since I purchased it in March. I don't notice it descending, but while climbing hard in a very rocky section, I have felt it. It is not a positive thing, however. It led to carefully inspect the wheel and suspension linkages. I have owned a very stiff single pivot bike that I could power out a rocky section and climb. Both my Tracer and my Mojo can not without showing some flex. IMHO, it felt better and I cleared the section easier with no flex. Now don't get me wrong, this bike performs excellent, and maybe because I'm a heavier rider is why I notice the flex. I know that Ibis redesigned the vertical strut, so I don't see why they couldn't stiffen it up a little. I'd upgrade my rear end. They could make the new rear end with the Mojo SL clear but more durable finish as well.
    Don

  47. #47
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    Pivot at chainline producing no reactivity is a perfectly valid way to analyze suspension, as far as it goes. What must also be considered is the thrusting force at the ground and its relation to the pivot. You would have absolutely no reactivity (0% anti-squat) only if the pivot also lies on the ground line.

    Taking moments around the swingarm pivot or around the IC of a true 4-bar is perfectly good physics. When the math is worked out you end up with the same method of calculating anti-squat as is used by DW and found in books like Tony Foale's.

    Another simple example: Consider a level swingarm and a level chainline. Counting the groundline you have three parallel lines. The force in the chain produces a compressive moment around the pivot equal to the force times the radius of the rear cog. The force at the ground produces an extending moment around the pivot equal to that force times the radius of the wheel. Now the force at the ground is weaker than the force in the chain in proportion to the ratio of the radius of the wheel to that of the cog. And the leverage from the force at the ground is proportionately greater than that from the chain by the same ratio. So the two moments exactly cancel out, giving 0% anti-squat.
    "Don't criticize what you can't understand."

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    Ow, my head hurts.

  49. #49
    mtbr member
    Reputation: doismellbacon's Avatar
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    ....hehehe..... He said hemmorroids

    Quote Originally Posted by ibisrox
    .....It's like comparing apples to hemmorroids!
    That's a good one!

    Maybe we could find a German Laboratory to compare these bikes' relative proficiency at preventing hemmorroids! Surely the Mojo would score highly! My smooth as silk '98 Ti Mojo is a relative ass jack hammer compared to Ibis' latest work of functional art.....I'm saving my pennies....

  50. #50
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    Reputation: Portti's Avatar
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    Quote Originally Posted by doismellbacon
    Maybe we could find a German Laboratory to compare these bikes' relative proficiency at preventing hemmorroids!
    The German bike magazines have done extensive testing on saddles which might include this type of testing.
    Pertti
    Lahti, Finland
    MC Kramppi

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