The Mikuni Power Jet kits are popular in 2 stroke engine applications because of their resulting improvement in mid-range throttle response and ability to add additional fuel to wide open throttle running conditions. These are easily installed on Mikuni VM and TM series carburetors and come with a full set of instructions. The general rule is to lower your main jet size by 25% and to then in the power jet kit install a jet of a size corresponding to the main jet drop. For example if you are running a size 300 (HEX) main jet you will reduce it by 25% =225 in which case as the hex jet is only available in increments of 10 over 200, you’d try a 220 or 230 main whilst at the same time installing a 75 power jet (available in increments of 2.5). Some experimenting may be required to achieve the perfect result but generally it’s as easy as following the fore mentioned formula. Use this formula to order your additional tuning jets when purchasing the Mikuni power jet kit, the kit itself comes with an 80, 100 and size 120 jet (N102.221 type).