Kwaka
NFC!
- Location
- South Africa
Anyone have specs for how much to take off where to lighten the stock SXR flywheel?
Lightening Stock SXR Flywheel
- Thread starter Kwaka
- Start date
- Location
- Idaho
No specs but info from GroupK websight
The stock SXR ignition flywheel works well, but it is not a particularly lightweight part. Reducing the weight of the flywheel rotor can noticeably improve the quickness of throttle response. This is best done in two different ways, lightening the stock flywheel, or switching to an aluminum replacement. The logical choice would seem to be simply switching to the lighter aluminum part, however many stand-up riders have found that an extremely light flywheel can offer response that is almost too quick for controlled recreational riding. That is, the lighter flywheel can allow the engine to accelerate so quickly that it creates more difficult throttle control and more violent porpoising (under acceleration), making the boat more difficult to manage. Riders call it a “light switch” feeling which refers to the “all on or all off” feeling of engine operation. The heavier stock flywheel actually helps to dampen that light switch effect to allow for smoother throttle control. An effective middle ground between the aluminum flywheel and the stocker is slightly lightening the stock ignition flywheel. Group K ignition flywheel lightening only reduces the flywheel weight by about .6 pounds, however the effect is significant because that weight is taken from the outer diameter of the flywheel where it hurt the inertia the most. More weight can be removed from the flywheel, but our testing showed that the long-term life of the flywheel became questionable with excessive lightening. In addition, this mod is a bit tricky because the trigger lobe on the flywheel OD cannot be touched. We strongly recommend the stock flywheel lightening for all Sleeper and Hammer kits. Note: no flywheel modifications are permitted in IJSBA Limited Class racing.
The stock SXR ignition flywheel works well, but it is not a particularly lightweight part. Reducing the weight of the flywheel rotor can noticeably improve the quickness of throttle response. This is best done in two different ways, lightening the stock flywheel, or switching to an aluminum replacement. The logical choice would seem to be simply switching to the lighter aluminum part, however many stand-up riders have found that an extremely light flywheel can offer response that is almost too quick for controlled recreational riding. That is, the lighter flywheel can allow the engine to accelerate so quickly that it creates more difficult throttle control and more violent porpoising (under acceleration), making the boat more difficult to manage. Riders call it a “light switch” feeling which refers to the “all on or all off” feeling of engine operation. The heavier stock flywheel actually helps to dampen that light switch effect to allow for smoother throttle control. An effective middle ground between the aluminum flywheel and the stocker is slightly lightening the stock ignition flywheel. Group K ignition flywheel lightening only reduces the flywheel weight by about .6 pounds, however the effect is significant because that weight is taken from the outer diameter of the flywheel where it hurt the inertia the most. More weight can be removed from the flywheel, but our testing showed that the long-term life of the flywheel became questionable with excessive lightening. In addition, this mod is a bit tricky because the trigger lobe on the flywheel OD cannot be touched. We strongly recommend the stock flywheel lightening for all Sleeper and Hammer kits. Note: no flywheel modifications are permitted in IJSBA Limited Class racing.
Kwaka
NFC!
- Location
- South Africa
Anyone have any pics?
- Location
- Idaho
Here are some pics on this thread
http://pwctoday.com/f13/800-750-groupk-lightened-flywheel-207648.html
http://pwctoday.com/f13/800-750-groupk-lightened-flywheel-207648.html
#ZERO
Beach Bum
- Location
- Florida - U.S.A.
Most people lighten those flywheels by turning the outer edge in front and behind the crank trigger pick-up points leaving the area between them untouched.
I'll be able to lighten those real soon between the trigger pick-up points after I get my motorized rotary table working and they'll look something like this flywheel.
I'll be able to lighten those real soon between the trigger pick-up points after I get my motorized rotary table working and they'll look something like this flywheel.
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Kwaka
NFC!
- Location
- South Africa
Very helpful, thanks.