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Can anyone tell me what size headtube fits a left fork? The bike i am buying has a 44mm internal headtube. Done a couple of google searches but some pages arent opening probably as i am at work 😉 Will a Lefty fit this? Thanks
Isn't it 1.5" for the lefty?
I thought it was some odd unique size, like 1.56"
It's definitely not 44mm, although there are adapters available to fit a lefty to a normal frame.
It definitely is, also meaning that you will need a Cannondale stem, and the bearings are non standard too. I just bought one!
It's not necessarily the internal diameter you have to watch, it's more the headtube length. The distance between the clamps on a Lefty is about 137mm...so the HT plus headset must be no more than that. There is a Lefty XL, with a a larger gap between the clamps too.
If the HT is short enough your best bet will be to go for a 'Lefty for all' steerer or one from Project 321. Both of these are standard 1.125 steerers, meaning you can use whatever headset and stem you want.
Any other questions just ask...I've just bought a custom frame designed around a Lefty, so have just had to go through what you're asking about.
I thought 44mm would accept 1.5" steerer tubes with the right external headset cups?
The Cannondale Lefty SI isn't the same as a normal 1.5" setup. The inside diameter of the headset is slightly larger and the steerer is part of the stem, not the fork.
you can get 1 1/8 steerers for leftys
IIRC Cannondale 1.5" headtubes are the same size as any other 1.5" headtube [b]but[/b] lefty steerers are slightly oversize compared with normal 1.5" steerers, so need a different headset.
Best bet is L4A or the Project 321 kit - these will work with normal stems. Length is going to be an issue though as the distance between the claps is fixed.
Having said all this, there are a few people out there with Leftys on non-1.5" bikes (including a Cove Handjob).
Andy