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Thread: I haz a sad

  1. #1
    ballbuster
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    I haz a sad

    Tonight, I had to take my Lefty off my RacerX29er. I just could not get that thing to not feel like a wet noodle.

    I feel the problem is my Lefty wheel. I have a DT Swiss X470 rim on there, and I can easily move it with my hand, and it felt like my front tire was flat the whole time.

    Now, here's my setup. Tell me if I'm missing something:

    Lefty Max 140, with 30mm of spacers to reduce the travel. 2005 or 2006-ish

    Project321 adapter clamps, for tall headtubes.

    Thompson stem (first tried an FSA 115OS stem)

    Titec H-Bar with Ergon grips

    Cane Creek S2 headset

    Cannondale Lefty Hub... silver
    DT Swiss X470 rim
    DT Swiss double butted 14/15 spokes, 32 laced 3x, at first normal tension, then tried higher.... not enough difference.
    DT Swiss brass nipples
    Kenda SlantSix tire
    Lunar Lite tube.

    I can grab the bars with the tire on the ground and flex it a lot. It also creaks. I checked all the torque values of the clamps, headset preload is good. I had no creaks with my Reba/FSA stem setup. The steering feels super vague.

    I think I just have to go back to the Reba setup for a while until I can isolate the issue.
    Last edited by pimpbot; 06-21-2011 at 04:05 AM.

  2. #2
    All Lefty's, all the time Moderator
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    Quote Originally Posted by pimpbot View Post
    I can easily move it with my hand,
    What do you mean by this?
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  3. #3
    ballbuster
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    Quote Originally Posted by MendonCycleSmith View Post
    What do you mean by this?
    bike on the ground, straddle the bike... grab the bars and I can flex the bars back and forth, watch the ground and the whole thing twists side to side... like a lot. Not enough for the tire to touch the Lefty, but not far off.

    But... this entirely feels like flex. There is no evidence of tap-dance going on... nothing loose per se.

    When I ride the bike, the whole front end skates around like I'm riding on marbles. If I go over 20 mph on smooth pave and take my hands off the bars, it starts to oscillate... speed wobbles... like really bad.

    The bike feels super disconnected from the trail.

    The thing is, part of the reason why I chose the Titus RacerX29er frame is that it is laterally super stiff. The bike is very point and shoot... it goes exactly where I point it, and what annoys me most about this is I lost most of that feeling with the Lefty setup.

    I swapped back my Reba/Real hub/32 double butted DT Swiss spoke/WTB Speeddisc rim setup, and all of it went away. Heh... this is even have a MK1 Reba Race, upgraded with a blackbox damper, but the MK1 Rebas are known for feeling flexy, but it was way more precise to ride than the Lefty... so I know something is way wrong somewhere.

    With the Reba setup, I can still grab my bars and flex it, but not nearly as much.

    I had a bud suggest that maybe what I'm feeling is the lack of stiction. I don't think that is what I'm feeling. I mean, I feel like I have to herd the bike down the trail with the lefty.

    I'm very tempted to send you the fork and Project321 adapter to get your opinion... at least a good servicing. Maybe send you my wheel too.

    I honestly don't trust any of the C'Dale dealers around here with any of this. If I brought my bike in, I'm sure they would tell me to buy a new fork and put it on a Cannondale frame, or throw fat cash at blingy parts I don't need that won't solve my issue. I really have no confidence in any of them.

    One other point: I did an oil change where I cycled the damper rod while upside-down to chase the air out of the top chamber, then filled it up, replaced the SPV bladder, and slowly pushed the excess oil out. After I put the bike on the car to drive to a ride, I found that it puked out a bunch of oil all over my hitch bike rack. It looked like the oil came out of the breather filter area. It didn't seem to leak during the ride, tho. I also noticed I tore my boot a tiny bit, so I gotta now replace that. I think my Thule T2 hooked it at some point and I didn't notice. Dang.

    So I'm not entirely blaming the Lefty for this. I really think there is something going wrong somewhere in the setup. I'm hoping it is something simple that I can isolate and fix.

    Man, I really want to get this to work.
    Last edited by pimpbot; 06-21-2011 at 10:12 PM.

  4. #4
    Ridin' dirty!
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    Did you check your spoke tension?
    Headset spacers/bearings?
    Maybe it's a lose crown....did you check both, upper and lower?
    Or it's just due to the fact that the lefty is a dual crown fork which might stress your frame too much and makes it flex excessively.....
    "Common sense isn't always that common!"
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  5. #5
    All Lefty's, all the time Moderator
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    If you grab the top of the wheel, and move towards the fork, and away, any play, like, bearing play?

    Stand in front of the bike, lock the wheel between your knees, grab the bars and turn side to side. Any palpable movement, or just material, twisting?

    Your experience, or at least, the way you describe it, is so far outside the norm, it's just got to have a physical factor, as it's not lack of stiction, "just the Lefty" etc.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  6. #6
    ballbuster
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    Yep....

    Quote Originally Posted by cdalemaniac View Post
    Did you check your spoke tension?
    Headset spacers/bearings?
    Maybe it's a lose crown....did you check both, upper and lower?
    Or it's just due to the fact that the lefty is a dual crown fork which might stress your frame too much and makes it flex excessively.....
    Spoke tension is good... I even upped the tension suspecting that was part of the problem. However, this is a DT Swiss X470 rim, and I'm pretty sure I'm over its weight limit by 15 pounds or so. It is a bit of a noodley rim. That said, I have the same rims on my singlespeed (also with a Reba), and it is not an issue there. Been running the same wheelset on my Singlespeed for 2.5 years without even needing a truing (and I built them myself). I don't tend to ride anywhere that beats on the rims too much.... just some off camper rocky bits sometimes.

    Headset is a Cane Creek S2, and it's good. No slop there.

    Crown bolts are snug... It's a Project321 crown and steerer tube with bolts at each junction, and I double checked them for snugness. All good. However, something in there is creaking.

    I have to wonder if there is an internal crack or something.

    Also, there is no slop between the upper and lower part of the Lefty. All bearings are snug, unless it is becoming un-snug under stress somehow.

    This is a RacerX29er frame. It's very stiff laterally and down the long axis. Using the same frame and headset with a Reba, I don't get the same flex or creaking. I'm sure the problem lies with the Lefty fork/Project321/wheel combination.

    I guess the only other factor I haven't addressed is the tire. I put a new SlantSix on there. Maybe I'll move it to the Reba wheel and see if the behavior changes at all. I doubt it, but all in the name of science, right?


    Quote Originally Posted by MendonCycleSmith View Post
    If you grab the top of the wheel, and move towards the fork, and away, any play, like, bearing play?

    Stand in front of the bike, lock the wheel between your knees, grab the bars and turn side to side. Any palpable movement, or just material, twisting?

    Your experience, or at least, the way you describe it, is so far outside the norm, it's just got to have a physical factor, as it's not lack of stiction, "just the Lefty" etc.

    No, more like just flex. No bearing slop.

    Maybe I need to do a more scientific Mythbusters style comparison. So much measured pressure at the end of the bars equals so much deflection measured at the wheel, and compare it to the Reba setup.

    I'm with you, tho. Something has to be broken here. I just can't put my finger on what.

    I wonder if the creaking is the steerer tube turning in the lower clamp... the one it's press-fit in? I could send it back to Jake and get his opinion. He's only a hundred miles from here, really. It doesn't turn by hand, I can say that.
    Last edited by pimpbot; 06-22-2011 at 07:00 AM.

  7. #7
    ballbuster
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    On second thought... I wonder if this is behavior has anything to do with higher bars, or taller A to C? I was always told the Lefty Max 140 was about the same A to C as a 100mm Reba. I forgot the actual number, but it was like within 5mm. Maybe I need to actually measure. I know there is a bunch more stack height above my headset.... more spacers and the top crown. The front end does feel higher. I am trying to run the clamps as far down the fork leg as possible (but still on the clamp area... I only really have like 5mm of room to work with anyway) to reduce A to C.

    I normally run my Reba with once 5mm spacer above the headset with an inverted 7 degree stem, with a riser bar. All is the same with my Lefty, except I had to put around 10mm of spacers under the top crown, the top crown, then the stem slammed on that (no spacers) and a few spacers above the stem on the steerer tube (that make no difference in geometry, obviously).

    I wonder if I'm just feeling higher bars and slacker head angle and more fork offset (38mm Reba vs 45mm Lefty)? I mean, it messes this bike up all kinds of ways. I actually like the steep head angle of the RX29er.

  8. #8
    All Lefty's, all the time Moderator
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    Quote Originally Posted by pimpbot View Post
    I wonder if I'm just feeling higher bars and slacker head angle and more fork offset (38mm Reba vs 45mm Lefty)? I mean, it messes this bike up all kinds of ways. I actually like the steep head angle of the RX29er.
    I'd look at this for sure. Higher bars will change your weight distribution, and depending on the A to C of your other fork, yeah, the Max is taller, most likely by a fair bit.

    You have an alloy Lefty, or a Carbon? Sorry, short on time at the moment, or I'd scour the threads for pics.

    If it's alloy, loosen your clamps, and slide the fork upward in them, it'll drop you a bit, and seeing as the RX head tube is fairly short, you can likely drop it a good chunk....
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  9. #9
    ballbuster
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    Thanks!

    Quote Originally Posted by MendonCycleSmith View Post
    I'd look at this for sure. Higher bars will change your weight distribution, and depending on the A to C of your other fork, yeah, the Max is taller, most likely by a fair bit.

    You have an alloy Lefty, or a Carbon? Sorry, short on time at the moment, or I'd scour the threads for pics.

    If it's alloy, loosen your clamps, and slide the fork upward in them, it'll drop you a bit, and seeing as the RX head tube is fairly short, you can likely drop it a good chunk....
    Yeah, alloy, and already dropped as far in the clamps as it can go.

    My RX29er headtube isn't that short, tho. With the 'tall' Project321 clamps, I still don't have a ton of adjustment available on the top clamp... like 7 or 8 mm or so.

    Heh... maybe I'll put it on my Hardtail... see what I get. I need another crown race. Tapping that thing on and off the steerer tube is a PITA.

  10. #10
    All Lefty's, all the time Moderator
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    Quote Originally Posted by pimpbot View Post
    Yeah, alloy, and already dropped as far in the clamps as it can go.

    My RX29er headtube isn't that short, tho. With the 'tall' Project321 clamps, I still don't have a ton of adjustment available on the top clamp... like 7 or 8 mm or so.

    Heh... maybe I'll put it on my Hardtail... see what I get. I need another crown race. Tapping that thing on and off the steerer tube is a PITA.
    Gotcha. I'd measure A to C and get an accurate picture of the difference you're dealing with, as it may well explain the disconnected feelings you have.

    In case you don't know, 1" of difference nets ~ a degree of HTA change....
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  11. #11
    ballbuster
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    If A to C is too tall...

    Quote Originally Posted by MendonCycleSmith View Post
    Gotcha. I'd measure A to C and get an accurate picture of the difference you're dealing with, as it may well explain the disconnected feelings you have.

    In case you don't know, 1" of difference nets ~ a degree of HTA change....
    I'm not sure there is much I can do about it. I already have the spring preload dialed all the way out (but takes up all of the slack in the black spring, so it doesn't clunk). Maybe I can live with a minor clunk if it brings the front end down enough.

    I hate to get into cutting a coil off the spring.

    Heh... don't need to do anything rash until I take some measurements. If my bars are too high, I might have to invest in a 15 or 20 degree rise stem and run it inverted.
    Last edited by pimpbot; 06-24-2011 at 09:36 AM.

  12. #12
    All Lefty's, all the time Moderator
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    Quote Originally Posted by pimpbot View Post
    I'm not sure there is much I can do about it.
    It's not so much that you can do anything about it, it's so that you understand the problem.

    From there, you'll be able to make an informed choice about which fork might be a better choice, say a 100, a 120, etc. Due to shorter A to C's they might keep your handling where you want it.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  13. #13
    mnt bike laws of physics
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    Quote Originally Posted by pimpbot View Post
    I'm not sure there is much I can do about it. I already have the spring preload dialed all the way out (but takes up all of the slack in the black spring, so it doesn't clunk). Maybe I can live with a minor clunk if it brings the front end down enough.

    I hate to get into cutting a coil off the spring.
    This is why I like the newer Leftys. The A-C can be dialed to your bike.

    One thing I can say that I am dealing with on my Tallboy is that the Lefty Max really doesn't seem to be designed to be run at full extension with a 29er for 110mm of travel. Mine run at full length like that is noticable more flexy that my other 29er Lefty run at 90mm. I am waiting for thicker inner races from Mendon to put on the TB lefty that may or may not help with that. Some of the races on it were the thinnest Cannondale makes.

    I do notice that my shorter 90mm Lefty does have more bearing preload so I am wondering if that makes a difference. It's not the main reason why I'm changing the races, but I do hope it is an extra benefit. Shortly, when I get the races, I will post up my experience with that.

    I don't feel play but I do think it makes a difference if they are "loose". I'm not sure if you would be able to detect it out right (such as a pivotal movement). But, I do have a hard time seeing that 20mm longer would make that much of a difference in stiffness (or flex). My longer Lefty has a beefier, stiffer wheel attached to it. Also, there is such different experiences in how stiff the lefty is. Case in point is CactusJack who claims his new Lefty Max on his Tallboy is wicked stiff and his setup is similar to mine (same length) except my wheel is beefier than his so this is odd. I know a person's weight (and therefore strength) will greatly determine stiffness and you are saying you aren't light but your still claiming your Reba setup is much stiffer so I am thinking that is not the issue here.

    Am very curious at this point is seeing how the difference in bearing preload makes on the overall stiffness. I have to say that when I first got my new 2011 Lefty max and converted it and put it on my Tallboy that I was immediatley underwhelmed by its flex and my first reaction was to blame the OPI lower. This is my first Lefty with an OPI...But I recently had an OPI lower put on my 90mm 29er Lefty because of a warranty thing with Cdale and it seems plenty stiff AND Craig just put an OPI lower on my 110mm SL (which has a 650b wheel) and it is plenty stiff too.

    I hope we get to the bottom of this....

  14. #14
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    Quote Originally Posted by yogiprophet View Post
    Am very curious at this point is seeing how the difference in bearing preload makes on the overall stiffness. I have to say that when I first got my new 2011 Lefty max and converted it and put it on my Tallboy that I was immediatley underwhelmed by its flex and my first reaction was to blame the OPI lower. This is my first Lefty with an OPI...But I recently had an OPI lower put on my 90mm 29er Lefty because of a warranty thing with Cdale and it seems plenty stiff AND Craig just put an OPI lower on my 110mm SL (which has a 650b wheel) and it is plenty stiff too.
    The OPI's are flexier. Add a longer arm to the equation, and yeah, it's gonna move around more. You aren't the first to notice, and Cannondales Lefty guys will tell you the same thing.

    Just one more example of how the persistent march towards less weight, often screws us as well in other ways.

    Preload and thickness will have zero impact on chassis stiffness, just travel plushness. More preload = less plush, slower migration.

    And since the Botsters fork is a 2005, he has the stiffer leg, so we can discount that aspect from the equation......
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  15. #15
    mnt bike laws of physics
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    Quote Originally Posted by MendonCycleSmith View Post
    The OPI's are flexier. Add a longer arm to the equation, and yeah, it's gonna move around more. You aren't the first to notice, and Cannondales Lefty guys will tell you the same thing.

    Just one more example of how the persistent march towards less weight, often screws us as well in other ways.

    Preload and thickness will have zero impact on chassis stiffness, just travel plushness. More preload = less plush, slower migration.

    And since the Botsters fork is a 2005, he has the stiffer leg, so we can discount that aspect from the equation......
    Okay, thanks Craig. I was told by Cdale personnel that the OPI was just as stiff or stiffer, but what you are saying does make more sense and confirms my initial impression of it. I suppose 20mm is really a noticable amount along with a longer wheel as far as lateral stiffness goes.

  16. #16
    ballbuster
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    Quote Originally Posted by yogiprophet View Post
    This is why I like the newer Leftys. The A-C can be dialed to your bike.

    One thing I can say that I am dealing with on my Tallboy is that the Lefty Max really doesn't seem to be designed to be run at full extension with a 29er for 110mm of travel. Mine run at full length like that is noticable more flexy that my other 29er Lefty run at 90mm. I am waiting for thicker inner races from Mendon to put on the TB lefty that may or may not help with that. Some of the races on it were the thinnest Cannondale makes.

    I do notice that my shorter 90mm Lefty does have more bearing preload so I am wondering if that makes a difference. It's not the main reason why I'm changing the races, but I do hope it is an extra benefit. Shortly, when I get the races, I will post up my experience with that.

    I don't feel play but I do think it makes a difference if they are "loose". I'm not sure if you would be able to detect it out right (such as a pivotal movement). But, I do have a hard time seeing that 20mm longer would make that much of a difference in stiffness (or flex). My longer Lefty has a beefier, stiffer wheel attached to it. Also, there is such different experiences in how stiff the lefty is. Case in point is CactusJack who claims his new Lefty Max on his Tallboy is wicked stiff and his setup is similar to mine (same length) except my wheel is beefier than his so this is odd. I know a person's weight (and therefore strength) will greatly determine stiffness and you are saying you aren't light but your still claiming your Reba setup is much stiffer so I am thinking that is not the issue here.

    Am very curious at this point is seeing how the difference in bearing preload makes on the overall stiffness. I have to say that when I first got my new 2011 Lefty max and converted it and put it on my Tallboy that I was immediatley underwhelmed by its flex and my first reaction was to blame the OPI lower. This is my first Lefty with an OPI...But I recently had an OPI lower put on my 90mm 29er Lefty because of a warranty thing with Cdale and it seems plenty stiff AND Craig just put an OPI lower on my 110mm SL (which has a 650b wheel) and it is plenty stiff too.

    I hope we get to the bottom of this....
    I don't think the extra travel is a factor in the stiffness of the fork, per se. What I was getting at, was the extra length (A to C) might be messing up my hanlding, making the bike feel flexier when I ride... making the front end wander around more.

    The 1st generation Reba 29er, tho... when I ran it at 80mm, it was pretty stiff... when I blew it out to 100mm, it was noticeably flexier.

    Anyway, no time to investigate this morning. Gonna take the hardtail for a ride.

  17. #17
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    I rode some technical, rocky sections today where occasionally I was loading up the bar while the wheel was in a rut on my Flash 29'er and I also have a soft front wheel, 28 spoke, carbon tubulars. Ya know it's not a "normal" feeling and at times I was wishing for a more rigid front end but when the bike is actually moving forward it doesn't seem to effect the handling in a significant way. I say it's always going to feel more like a noodle compared to something with a big, Enduro style front end but it's also gonna weigh lbs. less.
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  18. #18
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    I'd take a long look at your wheels...

    I'm riding a 130Max on a RX29er and it is WAY stiffer than either the Reba or Fox 29er I had on it. I run an AC wheelset which is a deeper profile and makes for a stiffer setup as well.

    I'm thinking wheel bearings or rim flex.
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  19. #19
    ballbuster
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    Any issue with clamping lower on the fork?

    I've been clamping the lower crown to the fork where the keyway ends.... so the bottom of the keyway is right where the bottom of the bottom crown starts.... kinda like the stock crowns.

    I can buy an extra 15mm or so below that... where the "Lefty" sticker is... if there is no structural reason to keep me from doing that.

  20. #20
    All Lefty's, all the time Moderator
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    Just had a fork in here with the same complaint as yours, felt "loose and wandery".

    Bearing preload was really light.

    He hasn't gotten it back yet, but I'm guessing it'll help him.

    Does yours feel really super easy to cycle during resetting the bearings? If so, up the preload to help the issue.....
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  21. #21
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    Quote Originally Posted by yogiprophet View Post
    This is why I like the newer Leftys. The A-C can be dialed to your bike.

    One thing I can say that I am dealing with on my Tallboy is that the Lefty Max really doesn't seem to be designed to be run at full extension with a 29er for 110mm of travel. Mine run at full length like that is noticable more flexy that my other 29er Lefty run at 90mm. I am waiting for thicker inner races from Mendon to put on the TB lefty that may or may not help with that. Some of the races on it were the thinnest Cannondale makes.

    I do notice that my shorter 90mm Lefty does have more bearing preload so I am wondering if that makes a difference. It's not the main reason why I'm changing the races, but I do hope it is an extra benefit. Shortly, when I get the races, I will post up my experience with that.

    I don't feel play but I do think it makes a difference if they are "loose". I'm not sure if you would be able to detect it out right (such as a pivotal movement). But, I do have a hard time seeing that 20mm longer would make that much of a difference in stiffness (or flex). My longer Lefty has a beefier, stiffer wheel attached to it. Also, there is such different experiences in how stiff the lefty is. Case in point is CactusJack who claims his new Lefty Max on his Tallboy is wicked stiff and his setup is similar to mine (same length) except my wheel is beefier than his so this is odd. I know a person's weight (and therefore strength) will greatly determine stiffness and you are saying you aren't light but your still claiming your Reba setup is much stiffer so I am thinking that is not the issue here.

    Am very curious at this point is seeing how the difference in bearing preload makes on the overall stiffness. I have to say that when I first got my new 2011 Lefty max and converted it and put it on my Tallboy that I was immediatley underwhelmed by its flex and my first reaction was to blame the OPI lower. This is my first Lefty with an OPI...But I recently had an OPI lower put on my 90mm 29er Lefty because of a warranty thing with Cdale and it seems plenty stiff AND Craig just put an OPI lower on my 110mm SL (which has a 650b wheel) and it is plenty stiff too.

    I hope we get to the bottom of this....
    I was a little underwhelmed as well after jumping on my new Tallboy and my new Lefty XLR90 29er. I'm sure I expected too much, but going to a lefty was why I was giving FS 29ers a second chance. It's not bad, it's just not great and stiff.
    My fork is a 2011 29er XLR with 1 10mm travel reducer removed.

  22. #22
    ballbuster
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    Well, define easy

    Quote Originally Posted by MendonCycleSmith View Post
    Just had a fork in here with the same complaint as yours, felt "loose and wandery".

    Bearing preload was really light.

    He hasn't gotten it back yet, but I'm guessing it'll help him.

    Does yours feel really super easy to cycle during resetting the bearings? If so, up the preload to help the issue.....
    I heard about the test where you take the split nut off, and let the fork hang. It should take two pounds of force hanging off the axle at the bottom to get the bearings to move. Mine is a bit easier than that, and it does slide down without adding any weight. There is some bearing resistance on all sides, as far as I can tell. It doesn't seem to have any play in any direction, but I'll check more closely to night when I get home. I'm pretty sure I checked for that. When I reset the bearings, I had to hammer it pretty hard. It was not easy, so I'm guessing at least two of the four opposing bearings are super tight.

    Did your client's fork have any noticeable play between the upper and lower tubes... as in, could you get it to tap dance by hand?

    If the needle bearing preload is the issue, is that something you can easily solve by moving shims around during a normal service... or extra credit service? Maybe that is a discussion better served through email and not here.

    Back to the A to C issue... oddly enough, I measured my 100mm Reba 29er 1st gen fork, and it was actually 1/4" taller unweighted than the Lefty Max140. I measured the sagged A to C on the Reba, but I don't have my notes with me to tell you what that is. I also have not measured my sagged A to C on the Lefty, being it's off the bike and all.

    The only other issue is my bar height. Obviously, with a top crown I can only slam the stem down so far. I normally run my Reba with one 5mm spacer to the top of the headset, and I run my stem flipped -7 degrees. I might need to look into a -15 degree stem to keep the bars down, or switch to a Titec J-Bar with no rise. Ugh.
    Last edited by pimpbot; 06-30-2011 at 10:49 AM.

  23. #23
    mnt bike laws of physics
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    Quote Originally Posted by pimpbot View Post
    I heard about the test where you take the split nut off, and let the fork hang. It should take two pounds of force hanging off the axle at the bottom to get the bearings to move. Mine is a bit easier than that, and it does slide down without adding any weight. There is some bearing resistance on all sides, as far as I can tell. It doesn't seem to have any play in any direction, but I'll check more closely to night when I get home. I'm pretty sure I checked for that. When I reset the bearings, I had to hammer it pretty hard. It was not easy, so I'm guessing at least two of the four opposing bearings are super tight.

    Did your client's fork have any noticeable play between the upper and lower tubes... as in, could you get it to tap dance by hand?

    If the needle bearing preload is the issue, is that something you can easily solve by moving shims around during a normal service... or extra credit service? Maybe that is a discussion better served through email and not here.
    You wouldn't be able to detect the play in the way of "tap dancing" unless they were very loose. The loose we are talking about is more subtle. since the bearings are so long. You could, however, detect movement in the way of flex instead of the typical pivoting movement that we are used to.

    I'm curious, my flex is mostly felt when I press on the right side of the Hbar and i'm sure that is mostly due to the added torque on the axle and because of the OPI lower having less material down there - there is more stress.

    Do you remember if that was how it was for you?

    Also, the inner races come in various thicknesses, so if you need more preload, you can just replace them with thicker ones.

  24. #24
    ballbuster
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    Well, yeah....

    Quote Originally Posted by yogiprophet View Post
    You wouldn't be able to detect the play in the way of "tap dancing" unless they were very loose. The loose we are talking about is more subtle. since the bearings are so long. You could, however, detect movement in the way of flex instead of the typical pivoting movement that we are used to.

    I'm curious, my flex is mostly felt when I press on the right side of the Hbar and i'm sure that is mostly due to the added torque on the axle and because of the OPI lower having less material down there - there is more stress.

    Do you remember if that was how it was for you?

    Also, the inner races come in various thicknesses, so if you need more preload, you can just replace them with thicker ones.
    I think for now, I'm raising my hand for help. Imonna send it to Mendy to do his magic on it. I'm a pretty reasonably mechanical guy, but I hate to booger it up with my hamfists unless I know more of what I'm doing, on this thing.

  25. #25
    mnt bike laws of physics
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    Just got my new inner races from Mendon today and slapped them in. If it did make a difference in stiffness, it wasn't significant. IOW, it may have made a slight difference. I think most of my flex is from the OPI lower combined with the longer travel and 29er mix.
    Having more bearing preload does help control the action a little more and will reduce bearing migration which I am very happy about. When I was taking it apart, two of the bearings were quite a bit lower than the other two which required that I compress the lower in more than usual to be able to push their inner races in to release the race clip.

    So, pimpbot, are you sending your in for MendonCS to check out?

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