i would keep all the idler wheels to prevent drag on the track and save your hyfax's do you have metal wheels?if so you can just upgrade to the plastic wheel wich is lighter and i believe slydog has lightweight idler wheels also.
MY SLEDS
96 XCR 600,psi tripple pipes,holeshot skidplate,2000 xcsp600 clutches,plastic ski's 136" coming soon.
94 indy sport 440,plastic ski's holeshot skidplate bone stock.