White Brothers power up kits

Stage I

The first step in increasing power on any 4-Stroke single is to improve intake and exhaust flow. This allows more air/fuel mixture into the engine to increase power and efficiency. WB offers many types of performance exhaust systems designed to improve exhaust flow and increase power.

Most stock airboxes on 4-Stroke singles are very restrictive and performance gains can be realized by simply drilling a few extra holes in the airbox cover and installing a White Powerfilter, Twin-Air Filter, or hi-flow K&N replacement air filter. The increased air flow resulting from the exhaust and airbox modifications may require slight richening of your standard carburetor jetting. All WB exhaust systems include rejetting information.

Stage II

The next move towards more performance is a larger, more efficient carburetor. WB offers the Mikuni performance carburetors that are larger and more efficient than your standard carb.

Many machines receive a significant power gain after installation of a larger carb, where other machines we recommend use of a larger carburetor only after a performance cam and piston are installed. Check with your WB salesperson or technician for their recommendation.

Stage III

Now we dive into the engine. WB offers performance camshafts for most 4-Stroke singles. These increase power by lifting and lowering the valves quicker, and provide a longer duration of opening for more fuel/air mixture flow into the cylinder.

Most performance cams require a heavy duty valve spring kit designed to handle the higher lift and more rapid opening of the valves. WB considers it a must that you also install a higher compression piston to match your performance cam. Remember, your piston is the pump that makes everything happen; don’t neglect increased compression when building your performance engine.

WB also offers Big Bore Piston kits for the 4-Stroke singles that reliably accept a larger bore. Nothing works better for achieving performance than to increase the displacement of your engine. Porting and flow testing can also be added at this stage. And don’t forget to have your valve seats checked and reground if necessary.WB, along with many qualified dealers, offers this service.
The finishing touch in your WB performance engine is the attention to detail. We recommend a good engine oil, plus frequent oil changes (this applies to stock motors as well), and hi-octane petrol (minimum 91 Octane Unleaded or Leaded). Race motors with 11:5 to 1 or higher compression will need an Octane Booster or Racing petrol.

Heavy duty clutch springs, oil cooler kits, non-resistor plug caps, plus many other accessories are also available. WB performance products are thoroughly tested and will provide significant power gains and excellent reliability when installed properly. All WB performance products can be easily installed. However, if you are not sure of your mechanical ability, have your parts installed by a professional.

Power up kits XR600 89 to 00