Quick Guide to H2 Performance Gain



Outlined below are steps to significantly improve H2 performance with minimal effort:


-Obtain 2mm copper lift plate for cylinder base


-Buy VM38 carbs

    -Use Q2 Needle Jet

    -Use 35 pilots

    -Use 6DH4 needles (same as VM 34)

    -Use 220-300 mains, dependent of pipes and tune


-Buy FKS 004 spigots. Mikuni brand, easily found on Nichecycles or Ebay


-Make the holes a bit oval for proper carb lift (to clear the cases). Not necessary if a 2mm lift plate is used.


-Use the ex port shape as described here. ROUND ALL PORTS AFTER PORTWORK. The edge cannot be sharp, more like touching a plastic comb so to speak.

    -For a real torquey, not so Wild set-up, do not raise more than the 2mm copper plate provides.

    -For a bit more lively tune, compensate the cyl lift by raising inlet duration by cutting and the make the profiled piston skirt. I would say max 3mm (1,5mm in total).

    -Make sure you get as smooth tapered exhaust duct as possible......there is A LOT of material (castings inside duct) to be removed after the window itself has been widened.


-Remove head gasket and use a high temp silicone sealing, for compression after the lift. The best way is squished-band heads and decked cylinders.




Hilsen Jørgen