Replacing Fox F100 RL Susp Forks with rigid

[2wheelsgeth]

I'm looking to replace the Fox F100 RL forks (100mm travel) on my 2008 Gary Fisher Big Sur with rigid forks, but am concerned about getting the geometry wrong. Can anyone recommend decent replacements, or at least tell me which measurements I need to get right? I can see me making a right mess of this if I'm not careful...

 

[RecordAceFromNew]

I believe the axle to crown (A2C) distance of your forks when fully extended is about 470mm. Assuming 25% sag e.g. for general XC purpose that gives an equivalent rigid forks A2C of 470-25%x100 or 445mm for maintaining headtube angle/bike geometry. Many rigid forks are available with that dimension.

Well that is partially the theory, since the offset of specific forks will also make a difference to trail and therefore handling, but I don't know if Fox even publish those figures for their forks, and it is not always possible to find such figures for potential rigid replacements either. We will probably have to assume new and old are similar.

Obviously choice will also depend on why you want to switch, given the F100RL has lock-out? and at around 1.7kg it is not exactly heavy for suspension forks. Although the lightest rigid mtb forks can save you 1kg, many rigid mtb forks weigh over 1kg too.

Many replacement mtb rigid forks have 1 1/8" steerer for 26" wheel and standard 100mm quick release front axle. You will need to decide whether you want disc and/or v brake fittings.

Hope it helps.

 

[2wheelsgeth]

I believe the axle to crown (A2C) distance of your forks when fully extended is about 470mm. Assuming 25% sag e.g. for general XC purpose that gives an equivalent rigid forks A2C of 470-25%x100 or 445mm for maintaining headtube angle/bike geometry. Many rigid forks are available with that dimension.

Well that is partially the theory, since the offset of specific forks will also make a difference to trail and therefore handling, but I don't know if Fox even publish those figures for their forks, and it is not always possible to find such figures for potential rigid replacements either. We will probably have to assume new and old are similar.

Obviously choice will also depend on why you want to switch, given the F100RL has lock-out? and at around 1.7kg it is not exactly heavy for suspension forks. Although the lightest rigid mtb forks can save you 1kg, many rigid mtb forks weigh over 1kg too.

Many replacement mtb rigid forks have 1 1/8" steerer for 26" wheel and standard 100mm quick release front axle. You will need to decide whether you want disc and/or v brake fittings.

Hope it helps.

That's brilliant - thank you very much. This is exactly the kind of thing that I was struggling to figure out.

I know the Fox forks aren't particularly heavy, but I have a preference for the feel and look of rigid forks (just old-fashioned, I suppose). And since the frame was designed for discs, there's not really too much choice on that front.

Thanks again for your help - really appreciated.

 

[2wheelsgeth]

[QUOTE 1652352, member: 45"]On-one do some nice, cheap rigid forks. As do Kona.[/quote]

Nice one - hadn't thought of On One. There's some good options out there.

 

[Globalti]

I put a pair of rigid carbon forks from here on my Ti frame: http://www.carboncycles.cc/ they are fantastically comfortable, so good that I'm going to sell my suspension forks.

 

[2wheelsgeth]

I put a pair of rigid carbon forks from here on my Ti frame: http://www.carboncycles.cc/ they are fantastically comfortable, so good that I'm going to sell my suspension forks.

They look really nice - thanks for that.