V-Force 3 Reed Valves

[ian wright]

I've just managed to fit a set of 3 Yamaha Banshee / YPVS 350 reed valves to my trackbike NS475.

It involved quite a bit of grinding out of material from the inlet castings to squeeze them in but looks like it will work well in conjunction with, bored inlet rubbers and NSR250 32mm carbs. To avoid having to bore too much out of the manifolds and avoid them splitting I've machined the outside of the carb stubs to reduce the external diameter so they fit easier.

I should be doing some dyno testing with this set up in the next few weeks so will be hoping to better my best bhp figure of 84 (my road bike, with standard reeds and carbs) to ??

Cheers Ian

[Seacoast69]

How did this end up working out ?

[OZZYSBIKES]

It would be interesting to know the outcome as there’s several alternative reeds for power valve yams,

[OZZYSBIKES]

I have acquired a set of spare NS 400 cylinders so I will be able to look at fitting 350 YPVS reed valve assemblies as I have spare ones for my YPVS, I'll let you know the results if still interested (seacoast ?)

[Doomman400]

any dyno results yet? i have a set of banshee reeds ready to go but dont want to grind away anything if there is no gain in using them!

[dinogt]

I have always put banshee reed box (350 LC 31K) in a 400NS... it is not plug and play.
VF4 must be very difficult to adapt