U.F.O.
(Ultimate Flow Optimizer) PATENTED

The UFO is a simple, trouble free, aerodynamic piece that fits Mikuni carburetors from 30 mm through 44 mm. The UFO makes a normal round slide carburetor out-perform the more expensive flat slide carburetor by eliminating turbulence and increasing air flow and velocity, creating a highly atomized fuel charge. Normal gains are 3/4 to 1 HP per 100 cc of engine displacement on 4 stroke engines and 1 1/2 to 2 HP per 100cc of engine displacement on 2 stroke engines. (Minimal rejetting and tuning are required).

Gain up to 7hp on your Banshee

Install UFO's on your Banshee and gain 5.25hp to 7hp.  The maximum gains will be in low end and midrange with modest gains on top end.  This is the biggest bang for the buck that's available (5.25hp gain on stock Banshee and 7hp gain with slight mods).

2628 - Yamaha Banshee carbs and (slide ID 24mm) 

3234 - Most 30 mm and all 32 through 34 mm carbs (slide ID 32.2mm)

The Majority of all applications require a 3.5 UFO Cut-away piece.
This is what is included in all kits as ordered.

When installing UFOs, the pilot jet must be reduced substantially (usually about 50%, sometimes even more).  Most installations end up with a 3.5 UFO and a #17.5 or #20 pilot jet.  These sizes are usually difficult to find locally.  Thunder Products has all sizes in stock for $4.00 each.  List your vehicle make, model and modifications in the special instruction box and we can give you a suggested size based upon our experience.  Or if you know what size you want, list that in the special instruction box and add the number of jets needed to your cart.

Pilot Jets

Idle Screw - Extra long idle screw for 40-44mm VM round slide Carburetors