Ignition System
Stock Kaw 650s turned about 6200rpm, and the stock limiter is at 7000rpms. This stock limiter is easily high enough to accommodate the 6600rpm of Rob’s stock-pipe F650. In fact this limit is also okay for most of the older aftermarket pipes (Westcoast, Mariner, Coffman, etc). However the Factory Pipe exhaust on our in-house F650 project has a peak between 7100-7200 rpm, and so a limiter mod was needed. By far the best limiter modification available is from Dale’s Jetsports in Texas. Dales sells a complete cdi box, with built-in coil, that eliminated the limiter altogether. We have found the Dales cdi to offer the best long term reliably of any of the mods we tried.
As mentioned above, the stock ignition flywheel is a very lightweight part, but it can be lighten even further. Group K does a lighten modification for these flywheels that reduces weight by about.3 pounds. The weight reduction is not huge, but it has a noticeable effect because we remove the weight from the outer parameter of the flywheel where it hurts the inertia the most. Rob opted to keep his flywheel stock, while we lighted the flywheel on our in-house F650.
The Kaw 650SX models never came equipped with a lanyard “dead-man” switch that came on all future 750 stand-up models. Since these 650s were both going to run considerably faster than a stock, we decided to get lanyard-style 750 hand-switches for both of theses 650s. We found these switches at a mail order salvage shop for a lot less that the $128 that the Kawasaki shop wanted for a new one. The installation was easy, and the added safety margin is well worth the cost.
Cooling System
