Viewing 40 posts - 81 through 120 (of 158 total)
  • Have we done this yet? – latest Chris Porter Geometry article
  • Northwind
    Full Member

    b r – Member

    And if your BB is below your axles then the weight is ‘acting’ the opposite to if the BB was above.

    Not in the way he’s talking, regarding braking forces. The hammock/pendulum effect is different.

    Taking it back to basics- within the same article he tells us lower is better on 26 inch and 650b bikes, but terrible on 29ers, does that make any sense to anyone but him?

    chris85
    Free Member

    Personally I think he’s absolutely spot on! Trouble is 90% of mountain bikers don’t ride steep techie stuff so won’t appreciate needing slack low geo. Others spouting off saying he doesn’t know what he’stalking about are clearly what I would call trail centre riders/ beginners.. pedal strike only happens to novices, so in that respect then yeah slack low and long is not for everyone

    jameso
    Full Member

    he’s taken it even further, probably to prove a point

    A great bike designer said that you always need to go further than you think with an idea, or go ‘too far’, otherwise you never know where the ideas limits are.

    andyrm
    Free Member

    One of Chris’ main things with 29ers is wheel flex, hence him saying about £1800 carbon wheels to achieve the same stiffness as a smaller wheel. And he’s clearly not so off the mark given the new 142+ format to create a better spoke angle and so stiffer wheel. Even at 72kg, I found the flex on the wheels on my 29er HT very offputting when ridden hard.

    There’s another article where Chris talks about having found the tipping point for the principle where it stops working in his favour:

    http://www.mbr.co.uk/news/bike_news/size-matters-part-2-finding-limits-geometry-sizing/

    It’s a good thing to have passionate people pushing the limits and finding the cutoff at which things stop – gives us the benchmark to do our own mods toward.

    I’m now running lower, longer and slacker than ever and will happily compromise XC style climbing and “fun factor” for speed and stability at speed – but then that’s down to a preference thing. I’ve never been interested in technical climbing (climbing is just the way to get to the top) or that nadgery low speed tech on the flat either – for me it’s all about DH speed, so anything that improves this is good.

    What CP has done is illustrate some things that anyone can do to their bike relatively cheaply (offset bushes, anglesets, short stem/wide bars) to make improvements for this kind of riding.

    Some people don’t rate going fast downhill as the key thing, some don’t – but it’s good to look at and listen to someone who is at the forefront of development ideas.

    andyrm
    Free Member

    A great bike designer said that you always need to go further than you think with an idea, or go ‘too far’, otherwise you never know where the ideas limits are.

    ^^This

    br
    Free Member

    Taking it back to basics- within the same article he tells us lower is better on 26 inch and 650b bikes, but terrible on 29ers, does that make any sense to anyone but him?

    I guess back to the braking issue, and with a 29er you can get the BB too low vs the axles.

    klumpy
    Free Member

    He dismisses 29ers and says road bikes are rubbish.
    10 out of 10!!

    brakes
    Free Member

    what are his metaphysical views on the totality of lateral stiffness and vertical compliance?

    makecoldplayhistory
    Free Member

    Someone should tell him to sign up to this forum, I feel he’d enjoy himself.

    This 😉

    I enjoyed the read, even if I didn’t completely grasp a lot of the more technical aspects.

    getonyourbike
    Free Member

    That Nicolai might be great on fast, wide open or really steep stuff but if you can’t get it around corners, like he proved at TP then it’s still a bad race bike. An enduro race bike needs to be fast everywhere (like awkwardly tight tracks), not just when it’s flat out.

    I’m a fan of long wheelbases and front centres with short stems, short chainstays make bikes more fun to ride on less extreme stuff and easier to handle when it gets really tight. CP might actually have been able to get the beast round tight corners if the chainstays were shorter…

    digga
    Free Member

    I think it’s a mistake to think any one single ‘way’ is universally correct. A lot of what CP says makes sense but it is counter to more conventional thinking.
    Fabien Barel’s recent revelations about his stem/bar set up, which goes against the “slam them as low as they can go” herd mentality are also interesting in a similar way.

    What works for some will not necessarily work for others. The stopwatch can’t lie, but it also can’t measure the feedback, fun and confidence a rider feels. It’s all very subjective, but overall it’s a good thing that there are people nudging the edges of the set-up envelope.

    Hob-Nob
    Free Member

    He’s obviously very passionate about his ideas, and as someone further up said, if people don’t try & find the limits, then nothing ever advances.

    I do agree with some of what he says, although maybe not in the way he says it.

    The big thing i’m not convinced on is his whole mantra of super long front ends & 10mm stems. I spent a lot of time last year riding a load of the Forward Geometry Mondrakers, and (which is the key bit – why we’re all different) for me, they ride like sh*t.

    They force you to ride in such a way over the front of the bike otherwise you have a lot less front end grip. I’ve never suffered so many front end washouts and feeling of looseness when riding anything else. I can ride noticeably better & faster on a more normal setup with a 55mm stem, which puts me in the same place on a current Mondraker Dune with their 10mm stem. That’s not to say that what I like is in any way better for the next person either.

    Let him crack on I say, its good we live in a world where he can put some of his ideas into reality. Even if they turn out to be hideous abominations like that Nicolai 🙂

    Brake-neck
    Free Member

    zero reach stems though? – a sure sign he’s gone too far.

    I don’t understand this comment, once you get used to the twitchyness they are great on the correct bike.

    AlexSimon
    Full Member

    I don’t get zero reach stems either. Putting the hands in line with the steerer, I can see, but behind!?

    Northwind
    Full Member

    b r – Member

    I guess back to the braking issue, and with a 29er you can get the BB too low vs the axles.

    The braking issue that I’ve never heard anyone else mention or notice, and that isn’t really backed up by logic or physics? 29er BB drop moves a small amount of grams a small distance, the overwhelming factor will always be the huge amount of grams still much further above the axles that you move around all the time. It’s like obsessing about pedal drag because mathematically you know it slows you down. Or, you know, declaring that you HAVE to spend £2500 on wheels to sort out a 29er.

    I’d be totally happy if he just said “I don’t personally like 29ers because X”, opinions are good and his are to pay attention to. But he doesn’t want to do that, so he uses pseudoscience and dubious “facts” like “29ers have no pump” to try and turn his opinion into fact. TBH it seems like a pretty common thing in mountain biking, people aren’t happy to say they prefer this to that- it has to be what they like is best, what you like sucks and you’re wrong.

    There’s a bunch of stuff I agree with him but the other stuff undermines him and the article. Especially when he changes his mind on something and suddenly his new gospel is as right as the old one was right up til he decided it was wrong. (see- 26 vs 650b).

    Shandy
    Free Member

    A rant about novelty-led product development and pandering to the lowest common denominator.

    From the guy who imports Fox CTD technology into the UK.

    walleater
    Full Member

    I don’t get zero reach stems either. Putting the hands in line with the steerer, I can see, but behind!?

    Yeah, maybe it works but I just have images of pushing a shopping cart.

    People seem to forget about bar sweep when it comes to stem length. My grips are in line with my steerer.

    Tom_W1987
    Free Member

    JCL, long chainstays push you over the front more and in turns keep the rear end more stable and less likely to break away. At the same time they are more comfortable through rock gardens.

    Long chainstays are the way to go in downhill.

    Tom_W1987
    Free Member

    I don’t get zero reach stems either.

    MX stem.

    ahwiles
    Free Member

    Brake-neck – Member

    I don’t understand this comment, once you get used to the twitchyness they are great on the correct bike.

    mostly, i was just talking shite.

    if they work, go for it, i just think they look a bit weird.

    mikewsmith
    Free Member

    Others spouting off saying he doesn’t know what he’stalking about are clearly what I would call trail centre riders/ beginners.

    aw bless, nice of you to still talk to those folks you seem to look down on 😉

    chris85
    Free Member

    mikewsmith – Member 
    Others spouting off saying he doesn’t know what he’stalking about are clearly what I would call trail centre riders/ beginners.

    aw bless, nice of you to still talk to those folks you seem to look down on
    POSTED 1 MINUTE AGO # REPORT-POST

    My comment does sound a bit arrogant and bless you I’m sorry if I offended you but you clearly do not understand his theory maybe due to lack of experience, but what cp is saying makes so much sense and I applaud him for having the balls and expressing his own opinion rather than being a typical sheep in the mtb industry…although I’ve never been a lover of Fox forks! 😆

    mikewsmith
    Free Member

    I’m happy on the steep stuff, I’m happy going fast I enjoy my bikes but really can’t be arsed with a lot of the stuff spouted about the “Perfect” bike which in reality is a bike for only one part of the experience. As you spotted it’s also really easy to come across as condescending 🙂 I hope you don’t get held up by anyone inferior today.

    It all reminds me of a trip to Rotorua in June where the guide we had for the day took us of pisteing on some seriously steep and loose trails one one of these

    For most people the bike is not the issue

    chris85
    Free Member

    It all reminds me of a trip to Rotorua in June where the guide we had for the day took us of pisteing on some seriously steep and loose trails one one of these

    For most people the bike is not the issue

    That’s awesome! 😆 😉

    chiefgrooveguru
    Full Member

    pedal strike only happens to novices, so in that respect then yeah slack low and long is not for everyone

    Come and ride our natural trails as fast as you can and you’ll learn all about the challenges of pedal strike! When the gradient is steep enough and corners large enough that you don’t need to get some pedal strokes in as soon as possible after the exit then super low BBs are great. But it isn’t always like that in the real world outside trail centres.

    Northwind
    Full Member

    Jared Graves pedal-struck a root at tweedlove and fired himself over the handlebars. But hey, he’s only a world champion so probably still learning the basics.

    oldnpastit
    Full Member

    Shorter cranks?

    JCL
    Free Member

    I’ve been advocating for 150mm cranks for years. Funny that Porter doesn’t mention that.

    chris85
    Free Member

    Northwind – Member 
    Jared Graves pedal-struck a root at tweedlove and fired himself over the handlebars. But hey, he’s only a world champion so probably still learning the basics.

    POSTED 1 HOUR AGO # REPORT-POST

    Oh jeeez…of course its gonna happen every now and then even to the pro’s
    But in general it’s a skill you learn to master even on the rockiest of tracks chief guru! 😉 where do you ride by the way? Sounds amazing! Surely you’d have picked up the skill of pedal positioning by now!

    futonrivercrossing
    Free Member

    My Jones has a super low BB – initially I had the odd pedal strike, but you adapt and I hardly ever have them now. I ride the same areas as Chief. Actually the low BB, slack, big offset, and long wheelbase of the Jones Plus has elements of what Chris is proposing……. Just a thought, And H bars will put your hands pretty much inline with the headtube.

    chiefgrooveguru
    Full Member

    It isn’t rocks that are the problem, it’s roots and stumps. Such is life when your local trails are through very twisty deciduous woodland. On the steeper trails it’s fine but on the flatter ones, or coming out of really slow corners on the steep ones, it’s all too easy to catch a pedal when you put down the power out of the exit whilst the bike is still leant over. Doesn’t help that I’m often riding them in the dark too!

    chiefgrooveguru
    Full Member

    FRC, I can’t easily find the BB height of your Jones but I’m guessing it’s around 300mm. And it doesn’t vary because you have no suspension. The BB height of my Spitfire is 346mm in the middle setting, so about 306mm sagged. Fully bottomed out it’ll be down at 200mm. Pumping out of a corner and then pushing the pedals it’s going to be well below the lowest rigid bike’s BB height.

    Northwind
    Full Member

    chris85, you’re a bit stalkery, you know that?

    So pedal strikes only happen to novices, except when they’re happening to pros. And that’s got something to do with where I ride?

    chris85
    Free Member

    Northwind, please do not take it to heart. This is my opinion that I agree with cp..he clearly knows more about mountain biking than you…again that is my opinion.
    To say that pros should never have pedal strikes is like saying they should never have a puncture or an otb…it happens, Just obviously the more riding experience you get you learn to manouver the crank arms about to avoid obstacles roots and rocks. I think you know exactly what I’m saying but your being slightly awkward mate 😉

    bigjim
    Full Member

    Others spouting off saying he doesn’t know what he’stalking about are clearly what I would call trail centre riders/ beginners.. pedal strike only happens to novices

    ahh, purest stw gold

    chris85
    Free Member

    Very good that Jim 😉

    M6TTF
    Free Member

    Interesting article. Some of it makes sense, some not so much, and some just smacks of I want to be different to cause friction.

    Comparing Moto gp handling to an mtb is frankly ridiculous

    continuity
    Free Member

    The only thing I took out of that is lose the clutch mech:

    And I only just bought one.

    Retrodirect
    Free Member

    FRC, I can’t easily find the BB height of your Jones but I’m guessing it’s around 300mm. And it doesn’t vary because you have no suspension. The BB height of my Spitfire is 346mm in the middle setting, so about 306mm sagged. Fully bottomed out it’ll be down at 200mm. Pumping out of a corner and then pushing the pedals it’s going to be well below the lowest rigid bike’s BB height.

    Actually, maybe someone could measure to be sure, but I believe the Jones BB height is somewhere in the region of 280. That’s REALLY low. You should be comparing sagged on an fs to the static rigid height, you’re not riding around with no air in the shock and the bike bottomed out all the time are you?

    bigjim
    Full Member

    The only thing I took out of that is lose the clutch mech:

    And I only just bought one.

    If you want to see what actual difference it makes, disconnect your shock and move the bike through its travel. Completely insignificant compared to the friction in a shock mount bush and of no concern wth your body weight flouncing around on top of it

Viewing 40 posts - 81 through 120 (of 158 total)

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