Excellent video, very good explanation and spread sheet easy to follow but:how much misalignment is acceptable to keep slippage and belt temperatures within parameters that provide decent performance and belt life?
The motor mounts are a compromise of alignment and vibration control and this compromise becomes more difficult as engine size and stroke length increase. Anybody that's ridden an 800cc or larger two stroke has probably felt vibration through their feet or through the handlebars.
Skidoo engineers are well aware of these problems but someone makes a decision on cost versus performance which includes vibration and this package was the result. One bright engineer discovered that machining the driven clutch with a 0.024" wobble at a predetermined spot on the rotation of the engine would reduce engine vibration without having to spend more money working on internal engine design such as crankshaft counterweights etc. Initial testing was positive so it was considered acceptable.
New engine with longer stroke and more power, more vibration, new clutch lighter design with less rotation mass and wobble driven clutch, new narrow chassis with limited air flow and tighter packaging of components, snow ingestion in the deep snow (steam) and the sled needs to be light weight, balanced, affordable and durable.
Evolution of the G4 continues:new clutching, new chassis venting, new motor mounts, lower gearing etc. our pocket books are getting lighter and the sled better but I am not convinced we are there yet and in 2 years we start again? JMO.
Happy Remembrance day to all the veterans.
The motor mounts are a compromise of alignment and vibration control and this compromise becomes more difficult as engine size and stroke length increase. Anybody that's ridden an 800cc or larger two stroke has probably felt vibration through their feet or through the handlebars.
Skidoo engineers are well aware of these problems but someone makes a decision on cost versus performance which includes vibration and this package was the result. One bright engineer discovered that machining the driven clutch with a 0.024" wobble at a predetermined spot on the rotation of the engine would reduce engine vibration without having to spend more money working on internal engine design such as crankshaft counterweights etc. Initial testing was positive so it was considered acceptable.
New engine with longer stroke and more power, more vibration, new clutch lighter design with less rotation mass and wobble driven clutch, new narrow chassis with limited air flow and tighter packaging of components, snow ingestion in the deep snow (steam) and the sled needs to be light weight, balanced, affordable and durable.
Evolution of the G4 continues:new clutching, new chassis venting, new motor mounts, lower gearing etc. our pocket books are getting lighter and the sled better but I am not convinced we are there yet and in 2 years we start again? JMO.
Happy Remembrance day to all the veterans.
