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  1. #1
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    42mm offset 29er forks

    anyone else out there interested in the 'new' fork offset geometry thats being touted? if available aftermarket i'd like to go from my 51 to a 42mm offset on my Smuggler and see if it provides the handling benefits discussed by Whyte bicycles and Transition. i've gone from 130 stock to 140 and trail would increase further with a 42 offset. could also be all bollocks and a waste of money, so it's unlikely i would pull that trigger if i'm to be honest with myself!

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    I am. Problem is I'm having a heck of a time locating a 160mm 29er fork with reduced offset. I'm currently limited to the MRP Ribbon and FOX 36 160mm 29er with 275 CSU installed.

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    i imagine they will become available to the public at some point but for the near future, a custom thing for a few manufacturers me thinks....

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    Won't make the difference you think til damn near stall speed. Tried 46 and 51 pike on my ROS, preferred 51. But at speed meh, YMMV. Don't blame the equipment.
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    What is this 2003? What are the "benefits" they are claiming?

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    Because the head angles get very slack nowadays, the trail increases to a level which seems to make steering awkward. So they go back to less offset.
    Just after we had increased the offset because after introducing bigger wheels we found out they handled awkward.
    Probably, if you would compare the trail of 2010s best 26" with the trail of 2015s best 29" it matches up with the trail of 2018s reduced offset bikes
    there probably are "golden numbers" somewhere, we just ignore them when we change some parts.

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    But that's not how it works. A larger wheel INCREASES trail. A slacker head angle INCREASES trail. A shorter fork offset also INCREASES trail.

    So as wheels got bigger and head angles got more slack, fork offsets got LONGER to battle the slow steering and handling that everyone complained about.

    This is going backwards, right to when everyone hated 29ers.

    Quote Originally Posted by Lochnes View Post
    Because the head angles get very slack nowadays, the trail increases to a level which seems to make steering awkward. So they go back to less offset.
    Just after we had increased the offset because after introducing bigger wheels we found out they handled awkward.
    Probably, if you would compare the trail of 2010s best 26" with the trail of 2015s best 29" it matches up with the trail of 2018s reduced offset bikes
    there probably are "golden numbers" somewhere, we just ignore them when we change some parts.

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    [QUOTE=Black Squirrel;13258724]But that's not how it works. A larger wheel INCREASES trail. A slacker head angle INCREASES trail. A shorter fork offset also INCREASES trail.

    bullocks, I managed to fumble it upside down again; you are right.

    which leaves me even more wondering "why?". had both a bigger and shorter offset fork on my bike and really liked the bigger offset better

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    Do the math.

  10. #10
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    Quote Originally Posted by Lochnes View Post
    bullocks, I managed to fumble it upside down again; you are right.

    which leaves me even more wondering "why?". had both a bigger and shorter offset fork on my bike and really liked the bigger offset better
    What do you consider as "better" handling? do you want a more nimble bike for tight and twisty trails or a more stable bike at higher speeds? Sounds like you prefer a quick steering bike, which would mean you want a higher offset fork. Example: Slack HTA's slow the steering down, using a fork with 51mm of offset will speed it back up a bit. Though it depends on what your after and what/where/how you ride, you may prefer less offset and more stable handling characteristics.

    I linked some good articles when I asked this question a while back. You can ignore the details about it being a rigid fork and what it's suspension corrected for and just stick to the info about offset, the same rules apply.

    Rigid fork offset
    Last edited by *OneSpeed*; 03-29-2018 at 03:53 AM.
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  11. #11
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    I've had two bikes that I was able to swap fork offset on back to back to see the difference. I preferred the larger offset on both for high speed and making my way quickly through tight trees. I the differences between the handling of varying offsets did not seem to align with the theoretical effect discussed. To me, both bikes seemed more predicable and more playful with the larger offsets, with fewer corrections required mid turn. The difference was more distinct on the rigid bike, but it also had a larger difference between the offsets trialed.

    Bike 1:

    Scott Genius 29, 140mm Pikes tried. 46mm & 51mm offsets.

    Bike 2:

    Scott Scale 29, ENVE Rigid fork (flip chip for changing offset, this is a great fork for experimenting with the affect of changing offset). 44mm & 52mm offsets.

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    Quote Originally Posted by *OneSpeed* View Post
    What do you consider as "better" handling? do you want a more nimble bike for tight and twisty trails or a more stable bike at higher speeds?
    Yeah, my greatest challenge is not hitting the trees, so like faster steering. More offset really did mean hitting less trees.
    Not that meany high speed downhill sections here, and on those ones we do have i"m already pretty fast

  13. #13
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    Quote Originally Posted by Lochnes View Post
    which leaves me even more wondering "why?".
    Some brands are looking for even more straight-line stability in their bikes. Certain bikes on the right terrain might benefit from that, like an all-out plow enduro race bike meant for relatively fast courses.

    Lengthening the reach is one option, and bikes have gotten a lot longer, but we're probably at the limits of what can be done there, within the constraints of sizing. Long reach has also allowed stems to get shorter, but you can't really make a stem shorter than 35mm (Pacenti P-Dent notwithstanding).

    You can slacken the headtube angle, which increases trail, but there's a limit there. AM/enduro bikes are settling around 65deg, as going slacker has other negative handling issues - keeping the front weighted, wheel flop, potentially reduced fork sensitivity, etc.

    You can lengthen the chainstay, but that affects cornering. It's hard to carve with a long rear end, as the first wave of 29ers demonstrated.

    And all three of those increase wheelbase, so the bike becomes harder to maneuver in general. Since we're over 1200mm in many bikes in the category, we might be the limit of what makes sense there.

    So, a few manufacturers are experimenting with fork offset to add more stability without the negative effects of the other options - it even slightly reduces wheelbase The steering input will feel slower, but that can be partially compensated with an even shorter stem. And for the speeds intended, you aren't exactly making super large movements of the bars anyway.

    For a more general-purpose trail bike, where you actually do care about low speed maneuverability, it probably doesn't make as much sense. But maybe we'll see a more modest change as a way to get more downhill capability in shorter-travel bikes too.

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    lazarus, that is definitely a good answer to the question "why".

    so, to get out of a corner of the "design box" which was starting to show deminishing results such as reduced fork sensitivity, this is a new direction. I can follow that.

    but, then comes the next question:
    <philosophicall alert>why do we all seem to want super downhill sleds? yes it is great fun but i think most distance is made outside the bike park. is it human behavior that we all seem to want big 4 x 4 "s to go to the mall and enduro downill sleds to do our local round?</philosophicall alert>

    lets get back to the technicall aspects.

  15. #15
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    Quote Originally Posted by brentos View Post
    I've had two bikes that I was able to swap fork offset on back to back to see the difference. I preferred the larger offset on both for high speed and making my way quickly through tight trees. I the differences between the handling of varying offsets did not seem to align with the theoretical effect discussed. To me, both bikes seemed more predicable and more playful with the larger offsets, with fewer corrections required mid turn. The difference was more distinct on the rigid bike, but it also had a larger difference between the offsets trialed.

    Bike 1:

    Scott Genius 29, 140mm Pikes tried. 46mm & 51mm offsets.

    Bike 2:

    Scott Scale 29, ENVE Rigid fork (flip chip for changing offset, this is a great fork for experimenting with the affect of changing offset). 44mm & 52mm offsets.
    This^^^ My LBS mistakenly ordered a 46mm offset SID for my new Scale build, was supposed to be a 51mm.
    They told me to ride it as is and that rockshox was sending them a new 51mm crown assembly.
    I rode my new Scale and was underwhelmed with the way my new Scale handled with the 46mm offset, to the point where I was questioning my bike choice.
    Long story short, the fork was changed to a 51mm offset and it completely transformed the way the bike handles, rather than thinking and muscling the bike thru turns it now became automatic, as it should be.
    I have noticed no loss of straight line stability, as it has been mentioned the front wheel should get knocked off line more easily with a larger offset.
    Count me in as a fan of the larger offset #'s

  16. #16
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    Quote Originally Posted by Lochnes View Post
    <philosophicall alert>why do we all seem to want super downhill sleds? yes it is great fun but i think most distance is made outside the bike park. is it human behavior that we all seem to want big 4 x 4 "s to go to the mall and enduro downill sleds to do our local round?</philosophicall alert>
    Well, it depends on terrain, intended use, etc.

    I'll be the first to admit that my 165mm super-enduro-AM-whatever leaves me overbiked for my local trails, and that I need to drive at least two hours to really stretch its legs. I'd certainly be faster and maybe have more fun on the weeknights with a little 110mm whip, but the super downhill sled bike is what I really do want on the weekends, when I can get to real mountains, bike parks, trails with features, etc.

    For a case like Anthem1's Scale, with more traditional XC geometry, probably doing more traditional XC riding, likely with lower peak speeds and for shorter durations, likely over less demanding terrain (sorry if I'm assuming too much about your riding, just generalizing), you'd naturally expect a different compromise to make sense.

    What I think's really interesting is what's happening in the 120mm-140mm trail bike category, where we're seeing bikes that are so much more capable than a few years ago due to improvements in geometry and suspension design, but still manage to stay light and playful. Maybe a shorter offset has some application there.

  17. #17
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    My other bike is a Pivot Switchblade with the Fox 36 also at 51mm offset, IMO 29ers with slacker HTA's is where more offset really shines.

  18. #18
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    I just ordered a Fox 34 CSU in 44mm offset for my tallboy 3 29er.
    I want more trail for stability, but the main reason it that the front is too long. I ride an XXL and the front to rear weight balance is shifted to far rearward. I need the decreased offset to help weight the front as I can't stretch the back out. I will report back in a month when I get the new CSU.

  19. #19
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    Quote Originally Posted by alexbn921 View Post
    I just ordered a Fox 34 CSU in 44mm offset for my tallboy 3 29er.
    I want more trail for stability, but the main reason it that the front is too long. I ride an XXL and the front to rear weight balance is shifted to far rearward. I need the decreased offset to help weight the front as I can't stretch the back out. I will report back in a month when I get the new CSU.
    Interesting, I too have an XXL bike (23" Fuel EX).
    I ride it as a plus bike most of the time, which makes the bottom bracket rather low. Running it in the high setting solves this but makes the trail fairly short. A taller fork could help, but the wheelbase is already quite long.
    The current trend is for longer bikes for stability, but that's because reviewers and engineers are talking about M and L size frames. XXL's are already quite long.

    Since most brands keep the chainstays the same length, the weight distribution is more rearward on a larger bike, so I think this idea makes a lot of sense.

  20. #20
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    Just got my new 44mm CSU installed today. Parking lot test: the bike feels shorter, but the steering feel very similar.

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    Quote Originally Posted by alexbn921 View Post
    Just got my new 44mm CSU installed today. Parking lot test: the bike feels shorter, but the steering feel very similar.
    Cool, let us know how it is on the trails!

  22. #22
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    2 rides on the bike. Set 2 PR's on steep DH sections. Can feel the extra feedback when leaned over at the limit. Still trying to find the balance and dial in the speed of the steering. So far I like it. No low speed side effects so far.

  23. #23
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    I went to 42mm on my ht 29er and like it better overall ( after playing w 46 & 51) but will say that the higher offsets work better ( for me) on our tightest, slowest tech trails here in Indiana. I won't be going back and in fact am in process of shopping for angle set in pursuit of a few more mm of trail.

  24. #24
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    Few more fork options:

    Use a new Rockshox 27.5 fork. Officially ok for 27.5x2.8, so smaller 29er tires should fit to. Note lower AC height, so might want to get longer travel.

    XFusion Mc Queen fork: 46mm offset and clearance for 29x2.6 officially, more in practice.
    Note very tall AC, so might want to adjust to lower travel.

    XFusion Revel upside down fork: "27.5" version has 46mm offset, then limit travel top keep tire from hitting crown/frame on full compression.

  25. #25
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    Reducing fork offset for taller riders

    moved to tall rider forums:

    here
    Last edited by Tjaard; 10-13-2017 at 08:58 AM. Reason: moved post

  26. #26
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    Quote Originally Posted by Tjaard View Post
    Few more fork options:

    Use a new Rockshox 27.5 fork. Officially ok for 27.5x2.8, so smaller 29er tires should fit to. Note lower AC height, so might want to get longer travel.

    XFusion Mc Queen fork: 46mm offset and clearance for 29x2.6 officially, more in practice.
    Note very tall AC, so might want to adjust to lower travel.

    XFusion Revel upside down fork: "27.5" version has 46mm offset, then limit travel top keep tire from hitting crown/frame on full compression.
    The 27.5 csu mates to the 29 lower for Rockshox, which is the route I chose. No additional clearance issues with that set-up.

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    Quote Originally Posted by SyT View Post
    The 27.5 csu mates to the 29 lower for Rockshox, which is the route I chose. No additional clearance issues with that set-up.
    that sounds nice, does this work? i have a 29er Pike from 2013 with the 46 offset and a good offer for a 27.5 csu (11.4018.008.419). I've ordered a carbon Smuggler frame an want to test the lower offset.

  28. #28
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    29er's have gotten more capable via better geo etc.

    So, naturally if people are riding them on steeper, faster, gnarlier terrain - they'll want it to be calmer when going mach chicken via reducing the offset.

    Totally logical Captain.

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    you won't have to test it, as your new Smug will come with it by design. or did you order a frame only?

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    Quote Originally Posted by cunningstunts View Post
    you won't have to test it, as your new Smug will come with it by design. or did you order a frame only?
    yes, frame only

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    i see. well they have made it with short offset 42/44 options but i'm sure the bike will ride well with a 51 offset too. my original smug has the usual 51 and with a works components headset -1 and 140 fork, sits at 66 degree head angle. i too thought about trying my 160 pike uppers with my 140 29r pike lowers but at 66 it's a dam stable bike as is and in tight twisty trails, i'm not sure i'd want more. not to mention the PITA factor to experiment.

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    One of the touted benefits is that reduced offset forks increase steering stability during large fork displacements.

    As your fork goes through it's travel the dynamic trail is reduced. On longer travel forks with 51mm offsets trail can actually go to negative values getting into the deeper travel leading to less steering stability when you need it most. The reduced offset forks remedy this issue by increasing the static trail to maintain positive trail values through the entire travel length of the fork.
    It takes half a joule more to accelerate Brass Nipples over Alloy Nipples on a 29er to 30kph.

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    Quote Originally Posted by cunningstunts View Post
    i see. well they have made it with short offset 42/44 options but i'm sure the bike will ride well with a 51 offset too. my original smug has the usual 51 and with a works components headset -1 and 140 fork, sits at 66 degree head angle. i too thought about trying my 160 pike uppers with my 140 29r pike lowers but at 66 it's a dam stable bike as is and in tight twisty trails, i'm not sure i'd want more. not to mention the PITA factor to experiment.
    Currently i'm also riding a '15 Smuggler but with -2° angleset and a Pike with 46 Offset and 150 mm. Nice ride, but with new ordered Smug CF, i want o go a step further with the offset thing.
    To my initially question: the 42mm CSU of the 27.5 Like (non-boost) will fit to the 29er lowers.
    With this solution I'm killing 2 birds with one stone, because my current steer tube is too short for the new Smug ,because i switched to one bigger size.

  34. #34
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    Quote Originally Posted by softbatch View Post

    On longer travel forks with 51mm offsets trail can actually go to negative values getting into the deeper travel leading .
    Care to provide an example? It would take a 82* ha at full compression (on a 29er) to approach 0 mm of trail.

  35. #35
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    Quote Originally Posted by flowbike View Post
    that sounds nice, does this work? i have a 29er Pike from 2013 with the 46 offset and a good offer for a 27.5 csu (11.4018.008.419). I've ordered a carbon Smuggler frame an want to test the lower offset.
    That works. If you plan on going coil, you can usually find the dual position csu considerably cheaper. ( you don't need the equalization dimple of the solo air for coil)
    Last edited by SyT; 01-22-2018 at 07:06 PM.

  36. #36
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    When you compress the fork and start to lean into a corner if your tire has to go over a rock that contacts your tire in front of your trail point it will change the direction of force on the bars. You can do this if you lean the bike way over rub the inside of a berm too. You can see it happen to minnaar in this clip.
    https://m.youtube.com/watch?v=3dzEJH8H7BI

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    I picked up a 2018 Specialized Epic with the 42mm offset fork and really like it the way it handles in the corners. Blah, blah, blah, set some Strava PRs, blah, blah blah. I do wonder if the bike needs to be specifically designed around them fork though?

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  39. #39
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    Quote Originally Posted by GlazedHam View Post
    I picked up a 2018 Specialized Epic with the 42mm offset fork and really like it the way it handles in the corners. Blah, blah, blah, set some Strava PRs, blah, blah blah. I do wonder if the bike needs to be specifically designed around them fork though?
    You probably bought mine.

    I sold two of them from my Epic frames because the handled like $hit with that bike.

    Unless you want to run a 80-90mm stem, which I don't, they do not work well on bikes with short stems.
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    I am in the process of building up an 160mm travel Evil Wreckoning and thinking about a running a 44mm Fox 36 after reading reviews on the Ralleon and Sentinel the reduced offset looks like it has its advantages.

    Should I go for it?

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    Quote Originally Posted by sb1616ne View Post
    I am in the process of building up an 160mm travel Evil Wreckoning and thinking about a running a 44mm Fox 36 after reading reviews on the Ralleon and Sentinel the reduced offset looks like it has its advantages.

    Should I go for it?
    What size is the frame?
    Making shit harder than it needs to be isn't awesome, it's just...harder.

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    Quote Originally Posted by sb1616ne View Post
    I am in the process of building up an 160mm travel Evil Wreckoning and thinking about a running a 44mm Fox 36 after reading reviews on the Ralleon and Sentinel the reduced offset looks like it has its advantages.

    Should I go for it?
    the Rallon is spec'd with standard 51mm offset. maybe you meant Smuggler and Sentinel?

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    I was thinking of trying it on my next bike whatever it is. The nice thing about the wreckoning is that you could also run an angleset to slack it out some.
    It takes half a joule more to accelerate Brass Nipples over Alloy Nipples on a 29er to 30kph.

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    the thing with Evil bikes is that they have short reach, so short offset forks only exacerbate this feature.

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    The Rallon does use a 44mm offset:
    https://www.orbea.com/downloads/prod...MR-2018-EN.pdf

    Both the Sentinal and Rallon use a slightly slacker HTA than the Wreckoning(hi mode), but the Wreck has more travel so the 66.1 head angle should be similar to the Sential's in sagged position.

    I am 5'-11" and thinking a large Wreckoning would be a good fit with a 44mm fork. I have ridden both. 3 long Sedona days on a med and 1 hour demo on the large. The med was defiantly nice and nimble, but cockpit feels cramped. I ride a large v1 Following now and the reach of the med wreck is shorter than the large v1.
    I run 760mm bars so that shortens the cockpit a bit also. The large wreck only has a 17.8" reach, but the ETT is super long, I think that number is false because Evil struggles to measure seat tube angles. The wheelbase of the large Wreck is also long at over 1200mm, but it's a bike designed for speed. I plan to have the saddle pushed forward on a non offset dropper like a reverb. At my height I am always right between sizes!

  46. #46
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    I would discourage any rider on a medium or small frame from getting a 44mm offset. Medium and Large frames start to have a preferred ratio of front to rear centers. XL and intentional long front center bikes need help maintaining this ratio.

    If you are sizing up to a large reducing the offset will help but more weight on the front wheel and allow you to raise your bars. It will also make the bike feel and be shorter. Since you are getting a mini DH bike the reduced offset will also make it more stable.
    Offset is a tool that you can use to balance the bike change it's feel. I say go for it. I would never go back to the 51 on my Tallboy 3.
    Making shit harder than it needs to be isn't awesome, it's just...harder.

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    Quote Originally Posted by sb1616ne View Post
    The Rallon does use a 44mm offset:
    https://www.orbea.com/downloads/prod...MR-2018-EN.pdf

    Both the Sentinal and Rallon use a slightly slacker HTA than the Wreckoning(hi mode), but the Wreck has more travel so the 66.1 head angle should be similar to the Sential's in sagged position.

    I am 5'-11" and thinking a large Wreckoning would be a good fit with a 44mm fork. I have ridden both. 3 long Sedona days on a med and 1 hour demo on the large. The med was defiantly nice and nimble, but cockpit feels cramped. I ride a large v1 Following now and the reach of the med wreck is shorter than the large v1.
    I run 760mm bars so that shortens the cockpit a bit also. The large wreck only has a 17.8" reach, but the ETT is super long, I think that number is false because Evil struggles to measure seat tube angles. The wheelbase of the large Wreck is also long at over 1200mm, but it's a bike designed for speed. I plan to have the saddle pushed forward on a non offset dropper like a reverb. At my height I am always right between sizes!
    interesting. the website geo chart shows 51. either way, i'm sure this bike would ride incredibly well with whatever offset one chooses. slightly different, but incredible. when Pinkbike tested the Sentinel they switched from the stock fork to a 51 standard fork and he said while slightly different, he quickly adjusted to the difference.

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    Thanks for the feedback guys, will keep you posted with the build!

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    Stem length to go with fork offset + offset location

    1. Has anyone changed their stem lengths once they went to a shorter offset?

    I read an article quoting Greg Minnaar indicating that your stem length should not exceed your fork offset. Transition went to a 40mm stem with their new bikes, down from 50mm. This compensated for the longer reach in the new frames, and coincidentally aligns with Minnaar's statement. My hypothesis is that a stem length that is close to or equal to your offset allows you to drive downwards with a vector that is parallel to the fork. This makes steering input more direct/immediate. Longer = you will drive down behind the front axle and push the front wheel towards the rider, too short = force is directed ahead of the axle and pushes front wheel forward.

    Anyone have an explanation that is more substantiated? I've been googling this for a few days and have not found any data or writing on the "stem = offset" theory.

    2. Is the Pike offset at the CSU or at the lowers? I saw that it is "stamped" on the inside, which helps you identify which offset you have. For reference, I have a 2016 Boost Pike 29".

  50. #50
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    Quote Originally Posted by smokinsnakes View Post
    1. Has anyone changed their stem lengths once they went to a shorter offset?

    I read an article quoting Greg Minnaar indicating that your stem length should not exceed your fork offset. Transition went to a 40mm stem with their new bikes, down from 50mm. This compensated for the longer reach in the new frames, and coincidentally aligns with Minnaar's statement. My hypothesis is that a stem length that is close to or equal to your offset allows you to drive downwards with a vector that is parallel to the fork. This makes steering input more direct/immediate. Longer = you will drive down behind the front axle and push the front wheel towards the rider, too short = force is directed ahead of the axle and pushes front wheel forward.

    Anyone have an explanation that is more substantiated? I've been googling this for a few days and have not found any data or writing on the "stem = offset" theory.

    2. Is the Pike offset at the CSU or at the lowers? I saw that it is "stamped" on the inside, which helps you identify which offset you have. For reference, I have a 2016 Boost Pike 29".
    On downhill bikes this might be true.

    On XC bikes like the new Specialized Epic, the 42mm offset is a disaster with shorter stems in slow technical areas of the trail. A 40mm stem on this bike results in constant washout of the front tire.

    Stable ripping downhill fast, terrible maneuvering at slower speeds.

    I sold both my 42mm Brain forks and replaced them with 51mm Fox SC.
    by Silentfoe
    I'm satisfied knowing that what I wear during my "day" job makes me more of a man than you'll ever be.

  51. #51
    SyT
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    Quote Originally Posted by smokinsnakes View Post
    1. Has anyone changed their stem lengths once they went to a shorter offset?

    I read an article quoting Greg Minnaar indicating that your stem length should not exceed your fork offset. Transition went to a 40mm stem with their new bikes, down from 50mm. This compensated for the longer reach in the new frames, and coincidentally aligns with Minnaar's statement. My hypothesis is that a stem length that is close to or equal to your offset allows you to drive downwards with a vector that is parallel to the fork. This makes steering input more direct/immediate. Longer = you will drive down behind the front axle and push the front wheel towards the rider, too short = force is directed ahead of the axle and pushes front wheel forward.

    Anyone have an explanation that is more substantiated? I've been googling this for a few days and have not found any data or writing on the "stem = offset" theory.

    2. Is the Pike offset at the CSU or at the lowers? I saw that it is "stamped" on the inside, which helps you identify which offset you have. For reference, I have a 2016 Boost Pike 29".
    The offset is in the csu.
    When I went to 42, I started with 35 mm stem. I've switched to 40mm and to me the feedback (able to sense the tire losing grip) through the bars feels greater.

  52. #52
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    Anyone looking for a RS Pike non boost 42mm offset CSU I've got a new one for sale at wholesale cost of $225.

    Ordered it to replace the 51mm offset boost CSU on my 29er HT and cut the steerer before discovering they sent the wrong one.It is cut to 182mm/7.165"

    I've got the replacement installed now for a few weeks and it does feel more stable at speed and less of an oversteer that I had been getting lower speeds.
    Last edited by joecx; 02-19-2018 at 03:49 PM.

  53. #53
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    Quote Originally Posted by SyT View Post
    That works. If you plan on going coil, you can usually find the dual position csu considerably cheaper. ( you don't need the equalization dimple of the solo air for coil)
    Can you explain this? The 27 vs 29 solo air dimples are not compatible?

  54. #54
    SyT
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    No, I mean if you are going to convert to coil when building the reduced offset fork, you can use the dual position csu ( doesn't have an equalization dimple) which can be ( or could when I built mine) found significantly cheaper than a solo air csu. If you are staying with the air spring, solo air csu is the only option.

  55. #55
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    So where does one go to buy a Fox 36 for the new Ripmo with a 44mm offset?

  56. #56
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    seriously? to the fork store, where else?

  57. #57
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    So, if I reduce the offset on my Trek Full Stache 29+ from 51mm to 46mm, it will handle slower?

    That seems counterintuitive to me. Isn't reducing offset not unlike decreasing stem length to increase responsiveness or decreasing HTA to increase stability?

  58. #58
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    It won't necessarily handle slower, but there will be more trail and a stronger on center feel.
    Making shit harder than it needs to be isn't awesome, it's just...harder.

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    Your stem length should match your offset” is bullshit.
    Why?
    Because a handlebar is not a broomstick! Depending on the width, sweep, rise and rollback of your bar, you are getting anywhere from 10-80mm of setback at the grips compared to the clamp.
    So saying that a 42mm offset needs a 42 mm stem and a 51mm offset needs a 51mm stem(10 mm difference) ingnores the fact that handlebar set-up has way more variability than that!

    Now, it might be true that shorter offset forks handle best with a shorter stem, but there is absolutely no basis for a 1:1 ratio.

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    Looks like Pikes are avaible with reduced offset now. and the new Lyriks too.

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    Quote Originally Posted by Nurse Ben View Post
    So, if I reduce the offset on my Trek Full Stache 29+ from 51mm to 46mm, it will handle slower?
    Depends what you call slower. It will increase trail, which will make the front wheel want to hold it’s line more.

    Quote Originally Posted by Nurse Ben View Post
    That seems counterintuitive to me. Isn't reducing offset not unlike decreasing HTA to increase stability?
    You said it yourself. Reducing offset increases trail, just as decreasing (slackening) HTA does.

    One more point. We are talking about 29er here. You have 29+. A larger wheel has more trail than a smaller wheel.

    For example, at 67 degree HTA, a 29+(70mm tire) will have the same trail as a 29er (58mm tire) wheel, if the 29+ has 51mm offset and the 29er has 46mm offset!

    So, in a way, you could argue, that since 29+ forks all use 51mm offset as well, they are allready “reduced offset” forks!

  62. #62
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    Quote Originally Posted by Tjaard View Post
    Your stem length should match your offset” is bullshit....
    Now, it might be true that shorter offset forks handle best with a shorter stem, but there is absolutely no basis for a 1:1 ratio.
    That is 100% true. The differnce in offset on a fork will have an impact in handling, but there is not set ratio. Factors like stem length, Head angle, ETT and desired handling characteristics are factors that go into what fork offset to use. Specialized appears to have taken a pro active approach to fork offset on their new FS Epic by purposefully going 42mm offset. They claim this was based on testing with a look at the rest of the geometry and purpose of the bike. Were they right or wrong? Depends on what you like as well.

    My Epic uses a 44mm offset Fox 32 step cast. I never rode it with the 42mm Reba the bike came with. I did this because I wanted the step cast instead of the reba and figured 2mm of offset was not going to be noticeable. 51mm might be so I wanted it as close to designed with the different fork.

    So far I find the bike to be very nimble and good handling and also stable on the DH runs. No complaints at all.
    Joe
    '18 Specialized Epic 29", Vassago Verhauen SS 29", '13 Santa Cruz Solo 27.5", XC, AM, blah blah blah.. I just ride.

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