Cannondale Lefty help

[jimbog]

Hi All, ive just got my hands on a 2001 f4000sl frame from the ebay Usa. I am looking into getting a lefty carbon for it but dont know much about them in terms of sizing.

I appreciate that loke all bikes the headtube lengths on cannondale frames vary, so do lefty forks come with different spacings between the fork clamp arms or do they adjust?

I see that the fork requires a headset sleeve insert/stem set up for the forks to clamp onto, which I assume need to be the correct length or can spacers be used?

My frame is 18inches ctc and the head tube is 14cm or 5.5 inches.

Is there anything I need to consider other then a lefty specific front wheel?

 

[old_coyote_pedaller]

Re:

Are you including the headset cups in the 140mm measurement? I've just measured 3 of my Cannondale Headshok/Lefty frames and head-tube is around 115mm but 140mm with the headset cups. Original Headshok frames like the F800 and Super V 1000SL bikes I have are all able to be retrofitted with Leftys no problem.

All the head-tubes should be same size from around that time, not sure about later frames, mine are all from '98 to early 2000s so that's what I know about. A Lefty should come with a steerer tube fixed to lower clamp on leg to fit in head-tube, all the same length. The upper clamp for Lefty leg comes off, the lower is fixed. Not sure about some of carbon Leftys as their clamps may be bonded on. You'll need a Lefty/Headshok specific stem as the steerer tube has a diameter of 1.56 inches, it's not 1.50 inches. Again not sure about later Leftys, more recent really, they could be different. Lefty/Headshok forks need a top headset bearing seal/cover that just slides onto steerer before the stem.

The major consideration with Leftys is maintenance and the tools required. Leftys really need lots more maintence than a conventional fork. The different tools necessary are different year on year. Some tools can be used on several different Headshoks/Leftys but the Castle tool needed to remove damping cartridge cannot be bodged. Try to remove without proper tool and you will definitely eff up your cartridge. I have 2 different Castle tools, one is an original Cannondale tool with small kidney adapter, the other is a supposedly universal Castle tool sold as "fits all Headshoks and Leftys", it doesn't. The original Cannondale Lefty tool is difficult to get a hold of and when they are they're expensive, £80 normally back when I got mine a few years ago in the Edinburgh Bicycle Co-op New Year sale for around £8 :mrgreen: . The 2 Leftys I have are from '99 and 2000, later one is the Titanium Lefty, the original Castle tool fits that no problem but doesn't fit earlier one. Neither does the so called universal tool. Headshoks are a minefield of different tools, luckily you don't want one. The universal tool fits some of Headshoks I have but not all.

You could fit a "normal" fork with either head-tube adapters or adapters that fit into the Cannondale headset bearings.

A couple of links for info and to help identify Leftys.

http://vintagecannondale.com/info/headshok/

https://www.eighty-aid.com/en/lefty

And bits

https://qwertycycles.co.uk/

https://www.tritoncycles.co.uk/?utm_con ... 9-59104961

https://www.cannondale-parts.de/epages/ ... Categories

 

[jimbog]

Thanks for the reply bud. Lots of info.

I seemed to somehow manage to get my measurements wrong. My head tube is 11.4cm and including headset cups 13.5cm, so more in line with what you said.

I gather from this that most 26 inch wheel leftys should fit, after all the f4000sl would have come with a lefty or fatty ultra.

Out of interest is the measurement between the clamps on your fitted leftys circa 14cm i.e. the length of the headtube and headset cups together? I am watching a lefty carbon on ebay and the clamps seem to be bonded on so I will need to check that they are the correct spacing.

I may opt to go down the fatty ultra route as the cost of a nice lefty, headset components and new wheel set will add up.

 

[old_coyote_pedaller]

Re:

Just re-measured and yes my head-tube including cups is 135mm, but I'd measured including the top bearing seal to get 140mm. :facepalm: Distance between clamps when fitted to bike is 140mm.
Not having a carbon Lefty with bonded clamps I'm not too sure of this, but if clamps are bonded the steerer tube could be separate and fits up through bottom clamp/headset bearings and is held in place by stem. Just my dim recollection of pictures I've seen. Don't take this as fact, I'm old and my memory ain't what it was.

The first Cannondale I bought was a Super V 1000SL frame off RetroBike. It came with a Headshok and the rather fragile bonded aluminium swing-arm that tended to crack. Mine had a crack but while searching internet for info found out that the CAAD4 swing-arm off a Jekyll fits straight on. Ebay to rescue which also supplied the 100mm Titanium Lefty and it's wheel as well. The Super V with the Headshok had 70mm of travel at front and around 100mm at back, with the 100mm Lefty fitted it was a more balanced bike. A good XC bike and not too bad on DH.

 

[fotorat1]

I am sure the headtubes are the same size apart from the later XL frames. also the very early steerer tubes were > 1.5 (1.57 I recall) but later on they dropped to 1.5. the only problem this causes is with Stems. - you havre to have the right one for the steerer.

If you are after a Carbon lefty - beaware that the upper tube clamps and boned in place- which means you cant replace the clamps.

Also watch out for the clamps being over torqued on the steerer tube- this can crack the bolt collar.:

This is my cracked Carbon Speed 110 ( with a 1mm hole to arrest the crack) - it is quite safe and doesnt get any worse.

The early alloy leftys 2002-2007 have removeable clamps, and have 3 coloured spings - I prefer the black spring which came standard on XL frames - these are my babies:

I am on the look for the Lefty with Fox internals for my old Rush!

 

[jimbog]

Re:

Thanks for the additional info fotorat1. Some nice cannondales there.

 

[The Malcolm]

Hi we have three lefty’s and a couple of headshoks on the bikes in the family and I would recommend the lefty. I service mine myself but I agree with earlier comments the parts are getting rare to find. To service them yourself do your research and invest in the specific tools. Companies like 88 aid will service some but I think even they have a limited supply of spares.

The earlier frames were all the same and now it is a minefield of lefty frame sizes as mentioned above.

For the wheel it is best getting a 6 bolt rotor type. Some of the earlier ones were 4 bolt and it makes finding rotors a hassle. I changed two of mine over to 6 bolt from 4 bolt. I found some bargain hubs on eBay for £30 a few years back and they were the same flange size and was able to reuse the same spokes.