Clutching

[kwcrawler]

Primary
Whats the differences of E ramps and F ramps.
Whats's the difference between Black spring and a yellow striped spring.
Does the primary get any lube between the bushings and the shaft?
 

[jimvw57]

According to the 1980 Invader manual, the Black spring is rated at 99.2 lbs, the yellow is rated at 77.2 lbs

the "E" ramp is for the 340  and the "F" ramp is for the 440

It also states the clutch should be assembled using Never-seez but don't use too much as it could end up on the belt once things start spinning.

[kawhead]

never seize on pins,
and shaft....f ramp is more aggressive....f and black spring is a good combo

[kwcrawler]

Had black spring and F ramps. Sled would hit about 20-30 MPH then fall on its face. It would be running 7500-8000 RPM running good then when hit around 30 the rpms dropped down to 4500-5500. Any recommendations on fixing it.

[gixxer6]

E ramps weren't just for 340's, they came on 440's too...  You're problem doesn't sound like a clutching issue to me.  Maybe you're running out of fuel?

[kwcrawler]

Going to go with getting seals put in first. I wonder if it is a weak fuel pump.
The clutch looked like it had a lot of weight on the arms.
More weight takes more RPM or less RPM to engage and hold clutch.
More weight needed to engage on steeper ramps: correct?

[kawhead]

i wouldn't try to tune without crank seals first