Briggs now makes the WF engine available under a different part number without the electric starter and clutch. Good deal if you are racing in some series where you do not these items or are replacing/updating your engine.
If it is the latter be aware that since it does not come with a starter there is also no plastic starter gear on the flywheel. I’m sure there is no performance difference with or without the plastic ring gear BUT some organizations (i.e. IKF ) require that ring gear to be on the flywheel with or without the starter on the engine. Personally I would like to see that changed. No starter, no ring gear is the way I would like it to read.
The only advantage of the starter is that you just push the button and it starts right up. For a one man team that may be a nice feature. I don’t like to have that extra weight on the kart especially hanging on the motor but to each his own. Some people do like it on the motor because that have to make weight.
The ring gear does take some HP away from the engine since it acts like a fan. It’s similar to old cars with the fan on the front of the engine. It takes HP to turn them.