I’ve reset the bearings on my Lefty a few times and the problem keeps recurring within the first ride.
It feels like there’s no damping for the top 20mm or so of travel.

I went a bit further today and stripped the fork almost completely and this is what I found.

The three white spacers at the top are travel reducers as it’s the 29er version.
Immediately below them is a small black spacer.

Below that is a white plastic cap that screws in to the top of the long red tube.
That cap was loose, completely unscrewed, when I stripped it.

You can see the bottom white cap off as well. I unscrewed that one.

There was a bit of oil everywhere, I take it the red tube should be a sealed unit with the two white caps keeping the oil in ?

So, the question now is, how much, and what type of oil, do I put in there ?
Is it two separate chambers, or are they linked ?
Fill it up, or leave a 10mm air space ? Or is there a specified volume ?

One other thing that I noticed is that the long flat steel tracks that the needle rollers run on are slightly curved.
Does that matter ? I can’t see it being a problem once everything is in place.

Sorry, I thought you were talking about the demise of the labour party.

Bump for the evening crew.
There’s a few how to articles on the web, but none of the ones i’ve found cover damper oil.
Anyone know the volume and grade or got a link ?

Log on to MTBR.com and go to the Cannondale forum.

Lots of knowledgeable folk there.

Hopefully Mendoncyclesmith will be online and he will sort you out for sure.

I thought Junkyard was having a breakdown…

I’ve asked on mtbr, no replies yet.
I cant be the only person in the UK to strip a Lefty. Someone must know.

I’m currently investigating how to service/overhaul my lefty – it isn’t hard, its just knowing what to do! I have found a few You Tube vids, one done in real time where a guy overhaul his in about 15 mins. Anyway I can’t answer your question from experience, but from the research i’ve done I thought the red damper unit is a sealed unit, so not serviceable and need to replace. There are alot of different Lefty models around so that might not be true for all, but certainly the research i’ve done so far suggests the damper is sealed.

Have you dropped Qwerty cycles an email? Sorry I can’t be more specific.

I thought this was going to be a report in how TJ was holding up following his expulsion from paradise.

Morning, I have serviced a few of these,

– it is one chamber, fill to the brim with oil, to the point that when you screw it back together some oil leaks out, this ensures you have no air bubbles, as you pour it in cycle the damping shaft up and down to get air out, (make sure the lock out is off).

– I just use motor cycle fork oil, you can choose the weight of it depending on your riding style. It may be worth changing some of the o ring seals, the original oil escaped for a reason.

– the bend in the bearing plates is not an issue.

All my bikes are dales and mtb’s have lefty but my lbs sort them out. So I’m no help tbh but I do have lefty’s

You’re best getting some ‘proper’ forks.

lefty’s usually use 5wt fork oil .The bend in the plates is pre load for the bearings so fine

Thanks, andrewlyness. I used 10 weight motorcycle fork oil and did it pretty much as you describe.
When I stripped the fork, as well as the damper unit top cap being unscrewed, the damper unit itself wasn’t particularly tight either. I undid it easily with a pair of circlip pliers.
To put it back together, I made an improvised castle nut tool.

The fork from the top, showing the castle nut top of the damper unit.

The tool. A bit of 25×5 steel strip cut, bent and ground to fit.

The tool in use.

Plus one to o-ring replacement the oil moved for a reason, o-ring, seals need replacing they ware out. I like your tool other fork techs I have worked with have made them out of plastic to do the job.

working on the inside of your forks with muck and filth everywhere? Sorry this isn’t much help but I’d be concerned about debris contamination. Good luck!

Below that is a white plastic cap that screws in to the top of the long red tube.
That cap was loose, completely unscrewed, when I stripped it.

Followed by…

It may be worth changing some of the o ring seals, the original oil escaped for a reason

and…

Plus one to o-ring replacement the oil moved for a reason

http://singletrackworld.com/forum/topic/forum-etiquette-people-who-obviously-havent-read-the-question 😛

jontawn, I overhauled the fork at home and tightened the castle nut as best I could with circlip pliers.
I took those pictures at work after only removing the top cap to tighten it properly with my custom made tool.

Every time I see there’s a new reply to this thread I’m disappointed now. I keep hoping it’s going to be the bicycle fork/socialism joke for a fourth time. 😥

Good improvisation!

Every time I see there’s a new reply to this thread I’m disappointed now

Here you go 😉

Is the a bleed screw hidden in the bottom of the lower shaft? There always was in the Headshok? As you tighten the plastic cap, you were meant to release pressure using the bleed screw (a bit of a bitch to get to IIRC) otherwise the oil is under too much pressure, feels over damped and can blow seals.

Walleater, I wondered about that bleed screw.
As I said at the start, “Fill it up, or leave a 10mm air space ?”
But then, andrewlyness said, “fill to the brim with oil, to the point that when you screw it back together some oil leaks out” so that’s what I did.
I’m worried now that as it warms up and the oil expands, it’s going to have nowhere to go.
I think I’ll remove the damper unit again tomorrow so I can get to the bleed screw and drain the oil down to that level so there’s a small air gap.

It does need to be completely full, otherwise the lockout has a bit of play in it (IIRC, it’s been a while since I worked on them), but by just tightening the white caps down the cartridge does stay under pressure even with oil leaking though the threads of the cap as you start to wind it down. If you’ve got the time / patience it’s probably worth pulling the cart again and unscrewing the bleed screw just to check that it’s not pressurized.

Hi there.
Just done a full strip down, oil replacement etc on a lefty. Got the tools etc. Dropped you an e-mail on your website. If i can help get in touch. Mobile number on e-mail Cheers Keith

I’ve been told by a bike machanic that 80aid is/used to be the service centre for cannondale

Disappointing, I thought this was going to be about old Tony Blairs being dismembered.

Every time I see there’s a new reply to this thread I’m disappointed now. I keep hoping it’s going to be the bicycle fork/socialism joke for a fourth time.

Thank you, pypdjl. Anyone want to make it five ?

And thanks, teamslug, but I’m sorted now with my home made tool.
That’s not my website, by the way, it’s just a club I’m a member of.

MidlandTrailquestsGraham – Member
Thank you, pypdjl. Anyone want to make it five ?

working on the inside of your forks with muck and filth everywhere? Sorry this isn’t much help but I’d be concerned about debris contamination. Good luck!

LoCo would say ‘Dirty!…. Dirty!’.

He was always having a go at me for not cleaning my forks before servicing them, although I think his level of clean is a good way above mine.