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  1. #1
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    Lefty Max Rebuild illustrated

    Well, I've done this twice now - with much the same experience - so I thought I would share. I don't know how to get the pics inline with the text, so I apologize in advance for making you scroll bakNforth.

    The basics: I own 2 Lefty Max's; a 130 TPC(converted to 1 1/8) (Pic1/2 - oops, no rebound damper asm shown) and a 140 carbon SPV(converted to 1 1/8 and 29er) (Pic3/4). Both of them have blown the rebound shaft seal at the top of the lower and started leaking oil out the boot. Both had a simple ORing, but now have a Quad seal (Pic5).

    To replace the rebound shaft seal, you follow the owners manual instructions to 1) take out the spring and 2) change the oil. Taking out the spring exposes the rebound shaft & seal, and changing the oil removes the compression damper, gets the oil out of the way, and lets you remove the rebound damper assembly to get it out of the way. All you need now is a 19mm socket, an 8" extension and a ratchet to remove the rebound shaft seal cap. Its the nut/washer looking bit between the bearing strips and the lower clamp in Pic 3. You will need a dental pick or something to hook the old seal out of the inside groove. Make sure the holder is clean, wet the new seal with oil and slip it into the groove - making sure its neatly in place with no rumples.
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    This isn't a "you're doing it wrong" topic.

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  2. #2
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    Part II

    So you might ask: why did you pull your telescopes apart when you don't need to do that to fix the rebound shaft seal?


    Well..... the seal leaks oil all thru the bearings and washes out the grease - so you need to clean it out as much as possible. And as you are doing this, you may notice that you should reset your bearings because one or more is not aligned with the others - as you cycle the telescope backNforth, you will notice that the bearings will leave a little lube line where they stop, and its easy to tell if they are aligned.

    Now, resetting bearing migration is easy - and covered in other threads as well as the owners manual. BUT! At this point, you have removed the rebound shaft seal holder - which apparently acts as the upper retainer of the bearing strips. With both Leftys my attempts at resetting while apart have resulted in pulling the telescope apart. And I note that in both cases I was checking alignment after each whack! And had not got it before sproing!

    OTOH, since I now had the beast apart, cleanup and regrease was easy. And now I know how to reassemble the telescope to boot

    To properly disassemble the telescope, you unscrew the large nut at the bottom of the upper (alloy) or pop out the wire internal snapring (carbon), remove the polyethylene bushing to expose the upper race retainer, unclip the upper races (T shaped) from the retainer by pushing the race to the inside while pulling on the retainer (hard to get it started, but it gets easier) and remove the retainer ring (these 3 parts are in the upper left of Pic3) Now the telescope can just slide apart - but you should be ready to catch parts and make sure you know where they were so you can get them back there - not critical but best practice.

    Now you clean everything, lightly regrease, and put all the parts onto the lower as shown in the pic. Except that you can't see all the parts (retainer/bushing/nut or snapring) that have to be on the lower before you start with races/bearing. And on the Carbon, you better pull the boot and air cleaner onto the upper before you put things together too!

    Lower races in place (wanting to bow out in the middle) and fully seated at the bottom, bearing strips halfway on (mid strip at top of lower) and upper races with the "T" two or three bearings down from the top and arcing out away from the assembly (which will put the middle bowing out from the inside of the upper). You may notice the "special tool" - which is actually two plastic caps fattened up with electrical tape. This makes life much easier for you, but don't get it any larger than the flat-to-flat dimension of the lower - it can pinch the bearing strip if you do. Once you have it together the tool will fall out the end easily.

    Then hold the lower/etc with one hand and pick up the upper in the other. "Clock" them correctly ( look at clamps vs axle) and slowly lower the parts together, lightly twisting them backNforth to make sure things are lining up. Keep an eye on the position of the upper races and the bearing strips to make sure they stay aligned. If something slips, back off and realign.

    When you're done, you may notice that now the upper races stick out too far. This is why you put the upper races together not in the middle of the bearing strips, and it makes it easier to get the T's into the retainer clip. You will have to "reset" the races/bearings a bit to get the clip seated, so if you think its easier to clip the races in down in their hole put things together centered.

    With the Alloy, you can use the big nut to push things into alignment as long as you are close enough to get threads started. Easy-squeezy. With the Carbon, you have to move the snapring onto the axle collar, make a sleeve (basically just like the bushing except slit so you can take it off later) to push everything down past the snapring groove and then just like bearing reset - except in reverse: whack it together instead of apart.

    Now reassemble the rebound damper shaft& seal, then hod it upside down and filler up (not to the top!) with oil, insert the compression damper -making sure that it is pushing the least little bit of oil out as it seats to make sure there is no air (holding a rag around the end will catch this).

    Zip the boot down, reinstall the spring, and put'er back on the bike. Don't forget to reset the damper dials
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    This isn't a "you're doing it wrong" topic.

    WSS/OSS: Open Source Sealant

  3. #3
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    I'm hoping I won't need to do this for a while, but is that quad seal a Cannondale part they are now using, or aftermarket? If Cannondale, when did they go from the O-ring to the Quad Ring?

  4. #4
    discombobulated SuperModerator
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    I believe the quad seal is Cdale, and they went to it in the last year or ...two? Someone should know for sure..
    CDT
    NICE WRITE UP!

  5. #5
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    Comments

    The quad seal is standard from CDale - but you have to buy the seal kit, which has everything in it., including the closed cell foam sheet that allows for volume change w/o air inside the damper on the TPC and FFD. One kit fits all 140, I think there is another for all 130.


    I hope you all get enjoy the writeup, I can tell I shoulda taken more pics - but with two greasy hands busy the camera stays put.
    This isn't a "you're doing it wrong" topic.

    WSS/OSS: Open Source Sealant

  6. #6
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    so whats the point of the quad seal? and which leftys have that?

  7. #7
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    Quad good

    The original Oring makes a simple line of contact with the housing on one side and the rebound shaft on the other. When you take a big hit and push the rebound shaft way down into the oil - you effectively pressurize the oil chamber (the foam sheet acts as a spring). On both my Leftys it took about a year to toast the Oring and start blowing oil thru the bearings onto the front brake/etc.

    The quad seal is nearly square and fills the groove almost fully - as opposed to the round ring in the square groove. The quad seal has at least twice as much area to hold pressure as the Oring, and should last at least twice as long.

    I thought the quadseal came in with the 140 - but apparently not since my 140 had an Oring. Definitely at least a year now.
    This isn't a "you're doing it wrong" topic.

    WSS/OSS: Open Source Sealant

  8. #8
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    Owners Manual?

    Great information! Do you have an electronic source for the owners manual? I did not receive detailed instructions with my fork.I have to replace my seal... If I understand you right, I remove the upper spring (this I've done before) and remove the lower bladder assembly (this too) and dump out the oil, remove the damper assembly (pull out?) With a 19mm socket and 8" extension I unscrew the nut from the bottom assembly and pull the unit apart. The o' ring is in a grove is located in the upper part of the assembly(??)... Remove it and replace with upgraded quad seal.

    It appears your picture (carbon lefty) is showing the approximate actual location of parts in an disassembled view, right??
    Last edited by MarkHL; 08-25-2006 at 09:09 PM.

  9. #9
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    Good Questions!

    Some answers:
    First off, the electronic source for most of this is at cannondale.com, specifically on the tech page for Leftys:

    http://www.cannondale.com/tech_cente.../en_lefty.html

    2005 Lefty Max 140 Owner's Manual Supplement - this is the full 140 Max Manual
    http://www.cannondale.com/Asset/iu_f...140_EN_web.pdf

    2002 Headshok Lefty Max & Jake Owner's Manual - the 130 Max Manual
    http://www.cannondale.com/Asset/iu_f...er/0114864.pdf

    2004 Headshok Lefty Max & Jake Seal Kit Tech Doc - this is the one in Pic2
    http://www.cannondale.com/Asset/iu_f..._Kit_QC685.pdf

    I have a few more, like "how to mount the Lefty speedo adapter" and a parts breakdown of the hub. I think they are still up there, but in other locations. Look at all the Lefty pages, its worth the time.

    In the CarbonLefty Apart (Pic3) the parts actually are mostly where they belong (wow - did I actually plan that? Cool) except for the clip/bushing/race retainer which should be near the lower end of the upper.

    The seal housing: When you pull out your spring and look inside - you are looking at it. It screws into the top of the lower, and the bottom of the spring sits on top of it. The rebound shaft can be pushed out from the top and will come out the bottom of the lower. You need the extension to reach down inside the upper. I think you said this, but...

    In Pic3, the seal housing is between the bearing strips and the lower clamp - and yes, the seal is in a groove on the inside. When you look at the Max/Jake seal kit doc (116071.pdf) shown in Pic2 - you can see a cutaway - quad seal would go where item#2 Oring is pointed out. And actually, the second page of the doc talks about this - look at the upper right diagram "location of ORing inside.."

    And Hey! Here's a pic of a complete 140 seal kit. KF225 is the part number. IIRC, about $5 from my LBS - ordered from CDale.
    Attached Images Attached Images
    This isn't a "you're doing it wrong" topic.

    WSS/OSS: Open Source Sealant

  10. #10
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    Quad Seal Replacement complete

    I did the quad seal upgrade tonight, it took about an hour.
    1) I had to bolt the fork back on the bike to break the nut assembly loose, I did not want to risk crushing the fork tube, damaging threads, or screwing up the spindle by using a vice. The lefty fork (non-carbon) is easily removed and reinstalled on the bike using three mounting screws
    2) Bleeding the lower chamber after refilling it is essential... inflate the bladder until it takes shape, then slowly insert the assembly and let the oil overflow, be careful not to let any air back into the assembly
    3) Getting the o'ring out is a bit tricky, make sure you don't use a tool that will scratch the seating surface, I used a plastic dental pick, still it took a few minutes. Rather easy to put the new seal back in... After gettting the fork reassembled, if felt like new... Lot's of adjustable rebound, no knocking sound when I lifed the front end and repeatedly dropped the front wheel on the floor from several inches up. I took it out for about a 90 minute ride and it worked really well. Quiet with no top out sound, or clunking and... no hydraulic oil on the lower assembly under the boot after I finished.
    Final thoughts, is it's pretty cool to have a fork that can be maintained (i.e., disassembled and reassembled) by the owner with normal tools.

  11. #11
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    YOU: Very helpful...CANNONDALE: Not

    Hi, I followed your instructions to reinstall the bearing races, and I destroyed the set of bearings, but that was my fault (pilot err). So I purchased new set races from LBS and proceeded to start all over. I found that a large o-ring (1.50 ID x .125 W) holds the bearings races better than a rubber band. The o-ring will “index” onto the ridges on the bearing races, and you can more precisely get the bearings centered and aligned. I used a small diameter piece of foam insulation instead of the plastic caps that you used for the outer races. After I pushed everything together, one of the races was sticking out farther that the others. So, what I did was to stack two old credit cards together to protect the lower raceway, and I forced the outer race into alignment to the others by tapping with a hammer and a screwdriver. It sound drastic, but after trying to get all of them to align closely the first time, which lead me to destroy my bearings, it worked. I tried to use the large retaining nut to push the outer race back into place, but that did not work. So, I used the tap hammer method, and tapped the outer races back where they needed to be. I used the Lefty manual to check the overall fork length, and it was defiantly longer than when I started, but within the dimensions shown; well now my fork boot seems to be too short. So what could I have done wrong? The fork seems to work fine.

    I e-mailed Cannondale to find out if they had any instructions for a lefty rebuild and bearing reassemble, and their reply:

    looked into this for you and unfortunately at this time we do not have a manual and/or detailed instructions on replacing the O-ring seals on the Lefty Max 140 cartridges. It is advisable just to get another cartridge, versus the time put into replacing the seals. Heather Egolf

    My Reply:
    Heather, do you know cannondale products? The lefty 140 Max HAS NO CARTRIDGE. The shock's parts are assembled into the body of the shock. So would you want me to go to my bike shop and buy a new Lefty 140Max shock/fork assembly (~$1100+) just because of a lousy leaking o-ring? Please!

    Her Reply:
    Whoops, I meant the damper assemblies, which I may still refer to as a cartridge. You can replace the damper assembly, no need to replace the entire fork. Now, if you mean the quad seal, it can be replaced. You can contact our Tech Support at 1-800-BIKE-USA for further assistance. Heather Egolf

    WHAT AN EFFIN NUCKLEHEAD…..

    Thanks for your instructions, Very helpful!

    PS: I had a Cannondale Fatty fork and rebuilt that one several times. It was different; I used an old inner tube as a bearing guide. It was tied off each end, and when inflated, it pushed the bearings onto the walls of the fork body.

  12. #12
    All Lefty's, all the time Moderator
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    Quote Originally Posted by fansaldi
    I e-mailed Cannondale to find out if they had any instructions for a lefty rebuild and bearing reassemble, and their reply:

    looked into this for you and unfortunately at this time we do not have a manual and/or detailed instructions on replacing the O-ring seals on the Lefty Max 140 cartridges. It is advisable just to get another cartridge, versus the time put into replacing the seals. Heather Egolf

    I believe this is what I was getting at a few weeks back, with my post about the "new" Cannondale. Exactly.

    Wadester, excellent, now I don't have to do it, but I ay anyway, just cause some folks don't like having to search= One thing, the bearing/race reassembly is made alot easier if the outer races are installed in the upper slider. Hold them in place with an inner tube, cut and tied at both ends, insert, and inflate.Apologies to Sanfaldi, you mentioned this too, but in reference to a headshock, this will in fact work for any Cannondale system, just needs to be longer for Leftys!
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  13. #13
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    Quote Originally Posted by MendonCycleSmith
    I believe this is what I was getting at a few weeks back, with my post about the "new" Cannondale. Exactly.

    Wadester, excellent, now I don't have to do it, but I ay anyway, just cause some folks don't like having to search= One thing, the bearing/race reassembly is made alot easier if the outer races are installed in the upper slider. Hold them in place with an inner tube, cut and tied at both ends, insert, and inflate.Apologies to Sanfaldi, you mentioned this too, but in reference to a headshock, this will in fact work for any Cannondale system, just needs to be longer for Leftys!
    Thanks Craig. I will look forward to seeing your writeup of this! I can see that the races-in-upper-with-innertube would work well. I know that once you get the bearings started in between the races everything is held tight anyways.

    Does the innertube method help prevent bearing pinch? My method seems to be very sensitive to this - requiring a finessed "wiggle" as you mate the assemblies.
    This isn't a "you're doing it wrong" topic.

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    Checklist

    Hi - great well written info.

    Could one of you guys who has done it post a checklist of all the things you need to make the quad seal upgrade.

    Blown though mine in the first season (2005 lefty max tpc bought in 2006)

    i.e. 22mm socket, 19mm socket, Oring kit KF225 etc etc - and also what oil/grease.

    I guess mine could be a warranty job (bikes 6 months old) but I want to have tools/oils etc to do it myself as need.

    Also would it make sense to do change the new 4 lip seal yearly to prevent getting oil everywhere?

    I know all the info is their, perhaps I am being lazy but I guess a check list would also help to make it clear for first timers like me.

    Thanks
    Last edited by dusttrails; 09-24-2006 at 11:57 AM.

  15. #15
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    List?

    Quote Originally Posted by dusttrails
    Hi - great well written info.

    Could one of you guys who has done it post a checklist of all the things you need to make the quad seal upgrade.

    Blown though mine in the first season (2005 lefty max tpc bought in 2006)

    i.e. 22mm socket, 19mm socket, Oring kit KF225 etc etc - and also what oil/grease.

    I guess mine could be a warranty job (bikes 6 months old) but I want to have tools/oils etc to do it myself as need.

    Also would it make sense to do change the new 4 lip seal yearly to prevent getting oil everywhere?

    I know all the info is their, perhaps I am being lazy but I guess a check list would also help to make it clear for first timers like me.

    Thanks
    First off, I bet that you will find an ORing, not the quad. I'd figured they went quad with the 140, but mine had the O - which blew. I'm keeping a spare seal kit on hand, but not planning on regular replacement.

    Tools: Go download the manual - it gives most of this (except the seal retainer cap)
    5mm allen to undo clamps/brakes/wheel
    ExtBB tool to take off the top cap
    19mm & 9mm openend wrenches to take off the top assembly and get the spring out
    22mm (TPC/FFD) or 24mm (SPV) to take out comp damper
    19mm socket + 8"extension/ratchet to unscrew cap
    Oil: Golden Spectro cartridge fork fluid 85/150 (got mine thru BTI/LBS)
    Grease: Royal Purple Ultra Performance Grease/ I use FinishLine teflon fortified grease
    This isn't a "you're doing it wrong" topic.

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  16. #16
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    As an info on quad seal.

    The Super Fatty that came with my 1FG has an integrated air chamber wich are no longer removable,and are bigger in diameter. It' got a quad seal in it. Works fine so far.
    "There is a big difference between kneeling down and bending over" -FZ

  17. #17
    All Lefty's, all the time Moderator
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    Quote Originally Posted by wadester
    Does the innertube method help prevent bearing pinch? My method seems to be very sensitive to this - requiring a finessed "wiggle" as you mate the assemblies.

    It does not really help prevent it, it just allows for an easier overall re-assembly. I can't recall if you mentioned this, but regardless of methodology, you want 11 bearings above, and 11 below the inner steerer. The pinch is best prevented through very careful wiggling upon reinstalling.
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  18. #18
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    Nice one - thanks very much

    Have ordered the Oring kit last week - will have to see which one I get

    thanks again

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    Thanks for a great thread. In the lefty supplement manual I was looking at the parts available and there are a number of inner race thicknesses. How would one go about selecting the proper thickness for the inner race?

    Thanks,
    Jim

  20. #20
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    Quote Originally Posted by jimpad
    How would one go about selecting the proper thickness for the inner race?
    First of all, all the outer races will be the same thickness, but those thicknesses vary. The inners can be all diiferent from the neighbors, so take them one at a time, leaving the others in place. Use a micrometer that does English (non metric). .021, .022, .023, etc.
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    I think I understand. Will all the inner race thicknesses be the same within the same fork?

  22. #22
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    Quote Originally Posted by jimpad
    I think I understand. Will all the inner race thicknesses be the same within the same fork?

    No, the outers will be the same thickness, but depending on the fork, those may be of a few different thicknesses. The inners in a given fork, may all be different from one another. Most frequently only one or two will be different though. Gotta mic them all though, to be sure.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  23. #23
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    Selection criteria?

    Quote Originally Posted by MendonCycleSmith
    No, the outers will be the same thickness, but depending on the fork, those may be of a few different thicknesses. The inners in a given fork, may all be different from one another. Most frequently only one or two will be different though. Gotta mic them all though, to be sure.
    OK, so the outers are all identical on a unit - but do come in different sizes. So the upper/outers will be symmetrical, and the thickness used will be based on the ID of the upper. Any "magic" distance race-race inside?

    The inners are all different, or matched across? Same Q?: Any "magic" distance race-race outside?
    This isn't a "you're doing it wrong" topic.

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  24. #24
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    Quote Originally Posted by wadester
    OK, so the outers are all identical on a unit - but do come in different sizes. So the upper/outers will be symmetrical, and the thickness used will be based on the ID of the upper. Any "magic" distance race-race inside?

    The inners are all different, or matched across? Same Q?: Any "magic" distance race-race outside?

    You would think so, but the answer is more nebulous. This difference in inner race thickness comes from a real world issue, over which there is little control. The outers are made in a fashion that allows there to be a high level of consistency. The inner steerer experiences changes in thickness due to machining tools getting out of tolerance over the course of weeks of production. By using variable thicknesses it allows them to maintain proper bearing preload, much less exspensively than re calibrating tooling every week or two. The rule for bearing preload is, extend the fork all the way up, and put a weight on the top of it. The steerer must drop with between 2 to 4 pounds on it, More than 4 lbs? Races are too thick, less than 2 lbs, races are too thin. Then, mic across the 2 inner axis's, take the thinner of the 2, measure their races, and replace the thinner of the two, with the next thicker. And so on, and so on. Have fun!
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    OK, if it's not already evident by my questions... I've disassembled my fork without noting race positions. So, if the races are selected to provide proper preload (and not concentricity) would it be reasonable to say the inner races will either all be the same or they should be paired ie. if not all the same thickness will two be the same and the other two the same? If so, it seems I should assemble the telescope such that a large inner race will be opposite a small inner race and the same for the other two?

    Thanks for the help.


    You would think I wasn't even reading your responses, well after rereading I've got it now. Ignore this one.

    Thanks again,
    Jim
    Last edited by jimpad; 10-21-2006 at 06:56 PM.

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    so, if I understand it right, there's no logical explanation of where to place each of the inner races? Just measure them, and start the procedure explained above?
    Another question; I'm trying to clean and rebuild my old fatty ultra, but the air valve has stuck in tho bottom of the fork. Is it okay to hit it as hard as I can? Or could be there something else?

  27. #27
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    Quote Originally Posted by derbence
    so, if I understand it right, there's no logical explanation of where to place each of the inner races? Just measure them, and start the procedure explained above?
    Another question; I'm trying to clean and rebuild my old fatty ultra, but the air valve has stuck in tho bottom of the fork. Is it okay to hit it as hard as I can? Or could be there something else?

    I guess to look at it from the backside, you want as even a square as possible. Keep flipping their position and re mic'ing till it's as square on both axis's as possible.

    As for your stuck air sleeve, it's most likely corroded into place, you can hit it, but be nice to it, use a punch that will fit next to the valve, so you don't damage the valve. Try some penetrating lube for a bit, from the bottom and the top, before commencing to Conan it=
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    Thank you, I guess I got the point. I wasn't sure if the different thicknesses of the races are not because of the different vectors of strength when the fork hits a bump. But it sounds stupid now I've read all your posts...

    The strange thing is, that after almost a year of searching I've bought a Cannondale Shop Manual on eBay. And though it's from 1997 -so pretty outdated- a lot of forks and cartridges are in it. But not a single line about the races.

    Now I go and hit the valve to protons and electrons...

  29. #29
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    Great post wadester. I ride a lefty carbon DLR, is that a completely different animal from the lefty max, or largely the same? Just wondering if I should finally get round to taking it apart to see whats what.

  30. #30
    All Lefty's, all the time Moderator
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    Quote Originally Posted by JBone
    Great post wadester. I ride a lefty carbon DLR, is that a completely different animal from the lefty max, or largely the same? Just wondering if I should finally get round to taking it apart to see whats what.
    Conceptually the same, but the outer steerers lower collar is very different in terms of removal. It consists of a round stock, steel spring clip, about 3/8" down inside the lower end of the outer tube. Both ends are crimped out a bit, you can catch them with a small screwdriver, and work them up and out of their groove. It's a PITA till you get the hang of it. Then there's a white Delrin sleeve that needs to be removed, try catching it with a dentists pick, and pulling it op and out. Once that's done, it will disassemble in much the same way as an Alloy version. Best done with a beer in hand for the first time=
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  31. #31
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    Good job! More experiences with the rebuild

    Thanks for the great work, this tread was crucial to me when downgrading from SPV to TPC on a alloy max 140. Also thanks to MendonCycleSmith for helping me with the parts and advice. I have a few comments where I had some problems.

    Rebound dissasembly:
    The first trouble was disassembling the rebound, I had to get a deep socket for it (19 mm) as the shaft stood up to high for my standard socket. It also was very tight unscrewing, and my strong brother cranked while I held the axle! Came loose at last, and seemed fine though.

    Races and bearings:
    The reassembly of the fork went well after I broke a bearing grid on the third attempt. I ended up using a disassembled Blackburn Fatty pump as a support for the bearings. Funny enough, the pump fitted the threads in the top of the inner! Perfect! I also used a 28 inch tube in the outer to hold the outer races, taped together double so I didn't need to discard it. Happy with that, because I tried at least 10 times to get it right!

    It cycled quite slowly when assembled, maybe because of the grease a bit to thick (Weldtite Bike grease with Teflon). Considered Finish Line with teflon, and PrepM, but went with the first. All the 8 races had the same thickness, 0,5 mm, and it needs more than 3,5 pounds of pressure to compress. Anyone have a comment on the grease?

    When fastening the big nut at the bottom at the outer, the races was out a few mm, and I had to cycle the fork a few times and then turn the nut a bit. Repeated until tight. Made some strange sounds, but worked ok. Then a bit of bearing reset, and on to the damping assembly.

    The damper assembly:
    The fork took quite a lot of oil, and the upside-down cycling trick worked very well - it sucked in a lot of oil. I put in too much of course, and when putting in the compression the oil almost hit the roof from the bleed hole! Good my wife didnt see it... I worked in the living room, the basement is so boring. The Motul 2,5w/5w fork oil gives both fast and slow rebound, quite perfect then.

    I had a small issue when getting hold of the rebound assembly again when fitting the spring, as I pushed it down in the fork by accident. Worked it out, but I could have to disassemble the compression and pushing it from the bottom. Would be a bit scared of the rebound shims if so.

    Other issues:
    Also, the pushrod had a dent, and a litte corrotion. I flattened it out, and it worked fine. Not sure why that has happened, maybe riding with to much migration over time?
    And of course, I put on the air filter upside down. I havent cared to turn it around as it mess up the fork with oil.

    I used a few hours on the races/bearings, but quite fun to do as a total. Hopefully it has stopped raining tomorrow, and I can try the "new" fork on some rough singletrack!

    -e

  32. #32
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    hi,
    anybody have any idea what makes my fatty70 move when locked out?
    If I turn the dial and push the fork it moves down about 1 inch, then stops. When lockout released, it makes a little noise like taking a breath and moves up by that inch.
    I filled the cartridge with new oil, there's no air in it. what is it???

    thanks, bence

  33. #33
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    Quote Originally Posted by derbence
    hi,
    anybody have any idea what makes my fatty70 move when locked out?
    If I turn the dial and push the fork it moves down about 1 inch, then stops. When lockout released, it makes a little noise like taking a breath and moves up by that inch.
    I filled the cartridge with new oil, there's no air in it. what is it???

    thanks, bence
    Sounds like air to me. Did you fully bleed it as is needed? Also, when it there, did you replace the seals? The one on the piston creates the lock seal, without it being nice and fresh, oil can weep past it.
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  34. #34
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    Thx waderster for the post - excellent!

    Question: a friend bought a new inner leg (the part with the axle). If I see this now I need new inner leg races with proper thickness. So how do I find out how thick races do I need? How do I order these without knowing the thickness?

    The inner leg needed to be exchanged because the brake caliper mount broke , or rather was worn out by the screw.

    cheers
    www.swotch.com - Tenerife Island Trail Web

  35. #35
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    Quote Originally Posted by Dotkom
    So how do I find out how thick races do I need? How do I order these without knowing the thickness?
    Welcome to hell. There's no formula, it's trial and error, and it may vary on each one, though generally they are within a thousandth of each-other, and usually are within a range of .021 - .025. Best bet is to obtain at least three or four of each of those, and swap them out till you get a nice bearing preload. Best of luck, let me know if you need additional help
    This is a Pugs not some carbon wannabee pretzel wagon!!

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  36. #36
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    The lefty manual on c'dales website (117105.pdf) shows everything except on how to remove the rebound shaft seal housing and seal. The manual also has some typos and it also miss-identifies some of the illustrations. If you have a SPV type damper Lefty, I have found that all you need is the quad ring seal (Quattro seal) because most all of the other seals will be in good condition and are static (no movement); the material is called Buna-N. If you feel the need to replace all the o-rings buy the set from c'dale (KF225) and measure them with a pair of calipers and note their sizes. Most o-rings conform to the AS568A standard. You can buy o-rings from a supply house like McMaster-Carr. The quad rings are numbered the same as standard round o-rings so the quad ring’s number will be AS568A-204 (1/8” thick X 3/8” Inner Diameter X 5/8” Outer Diameter). You’ll also notice that the o-rings do not exactly match the listed numbers. So when you measure to match them you just need to be close. (ie .109 x .365 x .619 = 1/8 x 3/8 x 5/8). The bike shop had me waiting for a month because c’dale had problems getting the foam strip for the FFC and TPC dampers. I hope this helps all of you.

  37. #37
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    The lefty manual on c'dales website (117105.pdf) shows everything except on how to remove the rebound shaft seal housing and seal. The manual also has some typos and it also miss-identifies some of the illustrations. If you have a SPV type damper Lefty, I have found that all you need is the quad ring seal (Quattro seal) because most all of the other seals will be in good condition and are static (no movement); the material is called Buna-N. If you feel the need to replace all the o-rings buy the set from c'dale (KF225) and measure them with a pair of calipers and note their sizes. Most o-rings conform to the AS568A standard. You can buy o-rings from a supply house like McMaster-Carr. The quad rings are numbered the same as standard round o-rings so the quad ring’s number will be AS568A-204 (1/8” thick X 3/8” Inner Diameter X 5/8” Outer Diameter). You’ll also notice that the o-rings do not exactly match the listed numbers. So when you measure to match them you just need to be close. (ie .109 x .365 x .619 = 1/8 x 3/8 x 5/8). The bike shop had me waiting for a month because c’dale had problems getting the foam strip for the FFC and TPC dampers. I hope this helps all of you.

  38. #38
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    I also found that when you use a 9mm wrench to remove the spring retainer assembly from the main shaft damper rod I slightly deformed the wrenching flat; I raised a burr. The last time I rebuilt the shock I noticed the burr and filed it smooth. My local bike shop told me to use Teflon seal tape to cover the wrenching flat to aid and protect the reassembly of the shaft into the rebound shaft seal housing.

    FYI- another bike shop said that I could use an old inner tube to cover the main compression spring to suppress any rattling noises. WHAT A EFFIN MISTAKE!! Never do this, the rubber of the inner tube disintegrated into a slimly black gooey mess. It took me quite a while to remove the pieces and clean out the upper part of the shock.

  39. #39
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    New question here. how to open lefty fork?

    Hi lefty fork experts , how did you open up your lefty fork? What tools did you use?

  40. #40
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    Quote Originally Posted by leadpack
    Hi lefty fork experts , how did you open up your lefty fork? What tools did you use?
    Uhm, a suggestion, you may just want to read this thread, perhaps... Or another idea, you could check the manual.

  41. #41
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    I've got a 2000 Lefty DLR that is basically new, but I want to make sure I have all the stuff I need for it if it breaks. I've go the bearings, seals,etc... but what I don't have is the exploded views and tech notes that I can see in the pics (background) of the first post.

    Can someone point me to a link or post that contains these?

    Thanks
    Mark

  42. #42
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    This isn't a "you're doing it wrong" topic.

    WSS/OSS: Open Source Sealant

  43. #43
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    5-week-old Lefty Speed Carbon SL ...

    ... not locking out completely, clunking also. Reset bearings, but fork bottoms out easily and perhaps that is causing premature migration? From what I can tell, sounds like there's not enough oil in the damper cartridge. I special ordered the fork, then a shop travel-reduced it 2 weeks later, so it didn't sit around long. Was locking out completely before reduction, however, I haven't seen any sign of oil leakage in the last three weeks.

    So, don't want to wait for Cannondale, and can't find a competent mechanic locally who is willing to rebuild it, therefore, want to do it myself.

    Questions: anyone have the service manual for this fork? It's not on Cannondale's website. If I could find one, I assume it will tell me what tools I will need: specific castle tool, spanner, seals, proper oil, etc. Will I need to completely disassemble to find out if I need to replace seals, and if not, I am also assuming I only need to partially disassemble to refill oil and bleed, and therefore not have to re-grease negative spring and other such stuff? Also, if anyone has any advice, i.e. what to expect, possible surprises, etc, that would be greatly appreciated!

    Fork feels wonderful otherwise, as stiff and plush (sounds like an oxymoron) as claimed. And freakin light.

    Edit: OK, there is a manual on there website (the DLR in the title threw me) but it doesn't explain the process to change the oil. Is it nominally different than the process for the others already explained here?
    Last edited by perioeci; 05-05-2008 at 04:16 PM.

  44. #44
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    i have reassembled my fork and when putting the pre-load spacers into the top of the spring i could almost slide them in without compressing the spring and once fully assembled the overall length was ok but the boot no longer covered the whole slider. Any clues as to what i have done wrong? i am a bit confused.

    cheers

  45. #45
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    If you have a shorter travel fork (110mm) you need to have more bearing rollers exposed before you insert the lower into the upper. If you have a 140~150mm travel fork you will need a new (longer) boot. All boots are the same now, you can count the pleats on a new bike in your local bike shop to determine if you have a shorter OEM boot; my lefty boot has 13 pleats. Please read all of the threads, they can help. There are some photo instructions attached you those threads, if you can't find them I can send you what I have; not the greatest, but they will give you some ideas.

  46. #46
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    Quote Originally Posted by MendonCycleSmith
    It does not really help prevent it, it just allows for an easier overall re-assembly. I can't recall if you mentioned this, but regardless of methodology, you want 11 bearings above, and 11 below the inner steerer. The pinch is best prevented through very careful wiggling upon reinstalling.
    Not to bump an old thread, but I found this out myself, wish I'd seen it earlier. I put 11 above and 11 below, slid the outer races in most of the way, then worked one outer race at a time wiggling it in to place. Used the big nut to finish them off. Worked great.

    Monte

  47. #47
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    Quote Originally Posted by Monte
    Not to bump an old thread, but I found this out myself, wish I'd seen it earlier. I put 11 above and 11 below, slid the outer races in most of the way, then worked one outer race at a time wiggling it in to place. Used the big nut to finish them off. Worked great.

    Monte
    This scares me, how, if I understand what you did, did the bit nut "finish them off"? You need the outer race retainer clip to be in place, and the outer races position is critical to proper placement. So, they need to be positioned prior to reassembly. Without that, you will likely damage the outer races, by tightening the big nut. This will scrape the crap out of your inner leg, etc etc etc. Unless I totally miss what your saying, this is why Cannondale has a tight lid on how to DIY these forks.
    This is a Pugs not some carbon wannabee pretzel wagon!!

    - FrostyStruthers



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  48. #48
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    Quote Originally Posted by MendonCycleSmith
    Unless I totally miss what your saying, this is why Cannondale has a tight lid on how to DIY these forks.
    Or not...if they wouldn't keep their lid as tight as they're doing, Monte would probably have done it the correct way. They're just bikeparts, and everything bike is pretty easy to work on. No PhD needed, but some instructions do make it a bit easier .

    Monte, like MCS says, all races need to be in their correct places before you mate the two fork halves. Maybe just to be sure open it up again and see if all is right. If you put the clip back on around the outer races I'm sure it is alright though.

  49. #49
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    Quote Originally Posted by Boozzz
    Or not...if they wouldn't keep their lid as tight as they're doing, Monte would probably have done it the correct way. They're just bikeparts, and everything bike is pretty easy to work on. No PhD needed, but some instructions do make it a bit easier .

    If you'd seen the number of forks I have, supposedly "fixed" by their owners, you might think differently. Folks often overestimate their skills, and make some really bad errors in judgement as to what's safe, and not. Not saying it's right or wrong, what Cannondale does, but I'd be leery, based on how many personal injury lawyers are making a comfortable living nowadays
    This is a Pugs not some carbon wannabee pretzel wagon!!

    - FrostyStruthers



    www.mendoncyclesmith.com

  50. #50
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    Quote Originally Posted by MendonCycleSmith
    If you'd seen the number of forks I have, supposedly "fixed" by their owners, you might think differently. Folks often overestimate their skills, and make some really bad errors in judgement as to what's safe, and not. Not saying it's right or wrong, what Cannondale does, but I'd be leery, based on how many personal injury lawyers are making a comfortable living nowadays
    True. Now also in the UK we're heading the way of the suing culture. Rediculous, can't stand people who don't know how to use their own brain anymore and who can't take the blame themselves for anything they do wrong. If you mess up, if you misjudge something, you pay the price. That's how I was brought up. Ok, rant over

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