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UPDATE - Corrections to my initial steps have been made. I hope this is clear now and with all of the necessary steps needed to complete this installation.

Disclaimer. I am not a bike mechanic, just mechanically inclined. I'm not afraid to tackle stuff like my Lefty or other projects. (I taught myself how to do the all plumbing from the ground up on my cottage. Yes, its all done all works too.) If you are not sure what to do and still feel tentative about doing the work, take the Lefty to your LBS if at all possible and have them do the work for you! You've been warned!


It finally came in the mail!!!

Lefty Max 140 TPC Kit.

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The tools...

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...and that's all for tonight. I need to stop by the local Crappy Tire store and pick up some oil for the Lefty.

Big thanks to Mendon for finally getting it out to me. Looking forward to installing it and getting back on the bike. I'll post up and let you all know how it goes.
 

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Well I couldn't exactly wait. So I got a head start on the work for tomorrow.

First off. Remove the Lefty from the bike. You will also need to take the top cap off. I put mine back on to keep any bits from falling out.

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Remove the air bleed bolt.

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Use a 22mm socket to loosen the FFD cartridge. A 22mm open ended wrench is good for un-threading it once loosened.

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Next gently pull the old FFD cartridge out. There will be some resistance due to the tight tolerances and the suction from the oil. But it does pop out eventually.

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Next pour out the old oil. Mine was quite dark. Time for an oil change anyways I guess. Also cycle the Lefty a few times onto a rag as the instructions tell you to. It will dump out a bit more oil which is trapped inside.

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TPC on the Left. FFD on the right. I'll keep it incase the TPC gets buggered up. At least then I'll be able to go back to the original set-up.

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The amount of old oil poured out of the Lefty.

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I also took advantage of the situation and reset the bearings on the Lefty and re-greased the bearing races et all.

Tomorrow. The rebuild.
 

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Man, that one was fast! Still want to know where the other one went....grrrr. You have to have the cleanest bench I've ever seen :D When refilling, make sure to move the rebound adjust fully to one end, and the other, cycling it several times at each point, otherwise there will be bubbles stuck in there. Rock on.
 

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Discussion Starter · #5 ·
Hey guy. What weight of oil do you recommend I put in there. The manual calls for some obscure stuff I've never heard of. I picked up some 10w at my LBS. After one of the techs there did a search on this site and found that 7-10w was acceptable. Should this be o.k.?
 

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prodigalcyclist said:
Hey guy. What weight of oil do you recommend I put in there. The manual calls for some obscure stuff I've never heard of. I picked up some 10w at my LBS. After one of the techs there did a search on this site and found that 7-10w was acceptable. Should this be o.k.?
Well, stock weight is Golden Spectro 85/125. This is more or less 2.5 wt. Thicker stuff will just allow you to use the lighter end of your rebound damping. If you are running a light or medium spring, I ould stick to 2.5, if you are using a firm or X firm, you'll be fine with 7, but 10 may be a bit thick. Good luck, have fun :)
 

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On with the show.

But first. Turn the fork back over and remove the main spring. Then put the whole assembly back together without the main spring. This will help with the next step. I won't get into the details of how to do this. Check the Lefty Max Manual section for instructions on how to replace/remove the main spring.



I used 5w fork oil. Like MSC says different weight oil changes the way the fork reacts. Initially I had put in 10w oil. But after the first re-build it seemed pretty sluggish. So I went with a lighter weight. What follows is a step from Craig of Mendon Cycle Smith.



"Pour the oil in, to within a inch of the top. Reach down to the bottom (normally the top, but the fork is currently upside down) compress the outer leg, and cycle the rebound shaft repeatedly. Have the rebound assembly together, only without the spring installed, as this will allow you to fully compress and extend the shaft. Turn the rebound to fully light, cycle fairly aggressively, turn to fully firm, repeat cycling. Note that the oil level has dropped by quite a bit. Top off, and and THEN install the compression assembly. Not doing this step will leave a ton of air on the backside of the rebound circuit, making the fork clack and click in a nasty way, also, rebound control will be nonexistant." - MendonCycleSmith.

Done. To Craig's credit. It does make a noticeable difference. I'm glad I went back and did it.

Then you insert the cartridge.



I didn't need to add anymore oil at this point either as there was still plenty in there.



So I cleaned it off with a rag. Also note that I wrapped a rag around the Lefty for just such emergencies. Saved me from having to cleaning oil up off the floor.



Next, the cartridge gets torqued down to 10 N-m.



Satisfied that I had wasted enough oil, the bleed screw is put in place.



Close up of the adjustment knob. The TPC kit itself comes with a spare o-ring and retaining nut for the adjustment knob.



Then the put on the adjustment knob. If you are new at this whole Lefty thing. Be warned that the knob has to be ordered separately if converting from FFD to TPC. Note how I lined up the bolts to use as a reference point for trail side adjustments. The knob turns almost a full 180 degrees, clockwise from this perspective, but not quite 180.



Finito! Not quite. I cycled the Lefty several times with the adjustment knob in different positions and opened up the bleed screw to let out any excess air bubbles. Some oil also came out as well. Lastly, I re-installed the air filter and washed the Lefty with a mild soap and water bath. Just to get the oily-ness off.



And that's pretty much it. No sweat.

Mendon (Craig). Believe me it didn't always look this neat and tidy. You should have seen the mess a couple of weeks ago. A years worth of crap and stuff thrown EVERYWHERE!!! This is the culmination of two weeks of steady re-organization and housecleaning. I'll seriously going to try and keep it that way from now on. :thumbsup:

 

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Bravo! Well done. You said, "pour in oil, insert cartridge....." It sounds like you were pumping the compression. I assume you were pumping the rebound? Just clarifying, as it confused me, and I'm sure many will follow your pictorial essay in the coming months.
 

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Discussion Starter · #10 ·
MendonCycleSmith said:
Bravo! Well done. You said, "pour in oil, insert cartridge....." It sounds like you were pumping the compression. I assume you were pumping the rebound? Just clarifying, as it confused me, and I'm sure many will follow your pictorial essay in the coming months.
I wasn't too sure how else to put it. How would you explain it?

I put the cartridge into the leg and opened and closed the valve several times while pushing it in to try and knock out the bubbles. Also once all was said and done and I had put it all together, I worked the the Lefty by pumping it like it was on the bike. I should add also that if you are going to do this make sure that the alloy knob is also bolted on. You don't want to shove down hard on that little adjustment spindle (snap!). Then I put it back in the clamp and removed the bleed screw. I figured if there was any air left in it it would have worked its way out (I think). I'm no expert at this by all means.

I did pick up some 5w oil later this afternoon. I figure if the 10w makes it too sluggish I'll just do another oil change.

I'll keep you posted.
 

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prodigalcyclist said:
I wasn't too sure how else to put it. How would you explain it?
Pour the oil in, to within a inch of the top. Reach down to the bottom (normally the top, but the fork is currently upside down) compress the outer leg, and cycle the rebound shaft repeatedly. Have the rebound assembly together, only without the spring installed, as this will allow you to fully compress and extend the shaft. Turn the rebound to fully light, cycle fairly aggressively, turn to fully firm, repeat cycling. Note that the poil level has dropped by quite a bit. Top off, and and THEN install the compression assembly. Not doing this step will leave a ton of air on the backside of the rebound circuit, making the fork clack and click in a nasty way, also, rebound control will be nonexistant. Hope that was clear enough, and that I have not created more work for you now :D
 

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Discussion Starter · #12 ·
Dammit! See they don't tell you to do that in the Manual now do they? There is no mention of removing the main spring and fully compressing the fork in that manner. I'll follow up. Thanks for the insight. Looks like I'll have a reason to add some of that 5w oil after all.

Shane
 

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Great Contribution Men

I have been considering upgrading my Prophet's Max and this was a big help --although I still may send it to you Mendon. Thanks for the awesome how to.:thumbsup:
 

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prodigalcyclist said:
Dammit! See they don't tell you to do that in the Manual now do they? There is no mention of removing the main spring and fully compressing the fork in that manner. I'll follow up. Thanks for the insight. Looks like I'll have a reason to add some of that 5w oil after all.

Shane
All of my statements are based on the assumption that you drained the fork. If all you did was turn it over, pull the FFD, add a bit of oil, and re install the TPC, this is not too much of a concern, since there was most likely not air, on the backside anyway. Still a good idea though, as a bit of air in there, will make noise, and since you are that far in, might as well make sure it's all happy!
 

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Discussion Starter · #15 ·
MendonCycleSmith said:
All of my statements are based on the assumption that you drained the fork. If all you did was turn it over, pull the FFD, add a bit of oil, and re install the TPC, this is not too much of a concern, since there was most likely not air, on the backside anyway. Still a good idea though, as a bit of air in there, will make noise, and since you are that far in, might as well make sure it's all happy!
Nope I drained it completely. The oil was kinda gross. I'll go back over it and do as you suggested. You're right about making sure its all happy. Thanks for catching it.:thumbsup:
 

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prodigalcyclist said:
Nope I drained it completely. The oil was kinda gross. I'll go back over it and do as you suggested. You're right about making sure its all happy. Thanks for catching it.:thumbsup:
When you drain it, make sure you pump the rebound too. There will be residual oil above, which will mix with the new, making it, less new :D
 

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Discussion Starter · #17 ·
MendonCycleSmith said:
When you drain it, make sure you pump the rebound too. There will be residual oil above, which will mix with the new, making it, less new :D
Yeppers I did that. Figured as much. Anyhow. Going on your advice, everything seems peachy. Thanks for catching that minor blunder. Your step involving the removal of the main spring in order to compress the Lefty fully when you add oil, does make a difference. :thumbsup:
 

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Q-Tip said:
Quick question. If you're not going to change the oil, taking the fork off the bike wouldn't really be necessary, would it? Maybe just take the wheel off?
No, just makes it a bit less cumbersome to work on. Not having a workstand though, this arguement becomes less viable. Doing it all with the bike upside down, wheel off, sounds great at that point :thumbsup:
 
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