Tell me about Lefty steerers -- e.g., MCFK, EP, etc.

Discuss light weight issues concerning mountain bikes & parts.

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Mattias Hellöre
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by Mattias Hellöre

Yes it can be stiff or whatever BUT, original cannondale steerer tube, the older ones are around 115 grams, your point is here. Save weight and using a 1 1/8 inch stem?

My tubes are consistently hovering around 75-80 grams for standard ones. Have made as low as 62 grams, as high as 99 grams.
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seismic
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by seismic

Do not see the problem with a 1 1/8 stem. Could you please elaborate?

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Mattias Hellöre
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by Mattias Hellöre

Fo a total freedom of stem choice, go for 1 1/8 inch steerer tube, but for best stiffness/weight - ratio a combo with steerer tube. stem and handlebar is best option but limitations are fixed angle and in a crash which destroys your handlebar, you are forced to replace the combo.

Lightest stems in 1 1/8 is AFAIK Extralite and AX Lightness, they both are not the stiffest either.
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trackdawson
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by trackdawson

I am curious, for those with the Mcfk steerer, how does the stem interface with the head tube. Specifically how does the crown race attach to the steerer?

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dwaharvey
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by dwaharvey

Like a normal fork does, aside from the fact that the lefty clamp goes on first and the crown race is pressing down onto: 1) the top of the steerer if it's the 1 1/8->1 1/2 tapered, or 2) the 1 1/2" shim/spacer that the lefty is clamping if it's the 1 1/8" straight version. (crown race is a tight slip fit on the steerer).

trackdawson
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by trackdawson

Thanks, until i found this site I was set on the project 321. The split ring under the race of theirs threw me.

awdnut01
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by awdnut01

I just replaced my Lefty steerer tube on my generic open mould 29er FS bike (1.5-1.125 tapered head tube) with Mcfk tapered carbon steerer. The 321 steerer assembly that I took out weighs 182gr while the tapered Mcfk carbon steerer assembly weighs 86gr

http://www.flickr.com/photos/117142033@N02/12447997045/

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