I am currently running 150mm Rocksox Sector solo airs with 20mm axle on my El guapo and am finding them a bit flexy fore and aft. I am looking for some stiffer forks that don’t cost a fortune and had settled on some X fusion Slants when my mate thew a spanner in the works and told me he can get me some Marzocchi 55 cr at trade cost. Unfortunately they only come with a 1+1/8 straight steerer against the tapered one on the slant but have slightly bigger stantions. Where is most important for stiffness in a fork steerer sise or stantion size?

Stanchion size will make a far bigger difference, particularly torsionally. You won’t find 55s lacking in stiffness.

Stanchion size will make a far bigger difference, particularly torsionally. You won’t find 55s lacking in stiffness.

i’ve got a pair of 55cr’s and have to agree they are stiff as hell!!
i’m a big marzocchi fan and will always go for their forks over other brands due to their stiffness and reliability…i’m happy to accept the extra fork weight for this too…

Based on considerable expensive experience, the through axle helps to stop the legs twisting, a tapered steerer reduces fore-and-aft flex and beefier stanchions reduces sideways movement in the corners.

Tons of variables, you could build a really stiff straight steerer or a really lightweight, less sturdy taper… Like, a QR Revelation with a straight steerer is still stiffer than a Fox 32 with a bolt-through and a taper.

I’ve just got some new old stock 06 130mm 20mm axle Z1’s from my LBS for a peanut packet of biscuits.. Not as light as newer 32mm legged forks and 1.18th steerer, but they’re like mini 36’s, stiff as a very stiff thing with that Marz slurpy squelchy plushness that they where famous for..

i’m happy to accept the extra fork weight for this too…

+1

stanchion size imho makes the most difference

I ddnt really notice till i put M4s on my 44s and see a lot more fore and aft flex when breaking
tho is suppose that could be the 15mm axle

by comparison my 66s with a 20mm axle are like well ard