VF4B Pivots

All the VF4B (Virtual Floating four bar) frames are equipped with entirely new pivot assemblies for 2008.

By reducing the complexity and part number I have made the pivots far easier to maintain, whist also reducing weight and increasing lateral stiffness.

For 2008 the Rune, Rampant and Pyre will all be using iglide polymer bearings. This decision has not been made lightly. We have considered all the pros and cons as well as done a substantial amount of field testing (actually I would say that hardcore BC trails are far better than fields for testing to the limits!)

what are the benefits?

• Increased lateral stiffness


• Reduced weight


• Reduced maintenance


• Cheaper for customers to replace


• Self lubricating

I realise that there are a lot of die hard bearing fans out there... but what you have to realise is that bearings are designed to take complete 360degree rotations like you get in bottom brackets, and not angular rotations (less than 90degrees) like you get in suspension pivots. This means that the whole load in bearings is constantly wearing out just 2 or 3 of the ball bearings in a conventional bearing, whereas the polymer bushings wear evenly due to the design.

You can find more information on the bearings here.. http://www.igus.com/show_iglide.asp and you can also order replacement bushings directly from them quickly and at a low price.

Axles:

The axles for the main pivots have been specifically designed for performance, simplicity, and ease of maintenance. This has been achieved by:

• Direct grease injection ports with set screw grease zerk


• Grease injection can be done in under 30 seconds, just unscrew the set screw, inject grease, screw in set screw. (obviously the area MUST be clean when you do this to stop grit getting in to the pivots)


• 3 parts to the axles... axle, bolt and zerk ... that's it, why over complicate things?


• Double helical groves on the axle surface to allow the grease to push under the bushings.


• Hard anodised finish to axle surface improves the life of both axles and pivots. (not seen in prototype above)

Basically the you inject the grease in through the end of the axle and it feeds through into the gap in the pivot between bushings due to the machined grease path. (you can see the grease paths in the following cross section picture).

Yes the bushings are self lubricating, so if they remain clean then there is no need to even grease the pivots, however if you suspect there is some grit in there then injecting grease can force out the grit without harming the bushings.

After spending months testing and abusing the prototypes that all had the new pivot assemblies we are very confident that they will help improve your riding experience.