Slipping centrifugal clutch on a BT-80

I know there was a discussion about this a few weeks ago between impulserocket and I, this is why I think it is a dry clutch
You must have missed my post about wet clutch versus dry clutch just before you made this one because we posted at the same time Gordy...lol.

 
I know there was a discussion about this a few weeks ago between impulserocket and I, this is why I think it is a dry clutch
Yeah, but also bear in mind that I don't have one of these engines and no first hand experience.

The design of the "gear box" is to have a small amount of oil mainly there for the benefit of the bevel and counter gear that would be the clutch gear on a normal engine. The picture of the covers provided leaves an open space for oil to get into the clutch area.

That said, I know the oil capacity is about 200ml, which is basically just enough for the oil to contact the gears and get circulated. The clutch drum also faces away from the engine. This leads me to suspect that the clutch isn't a true wet clutch, but is not fully dry either, and they may rely on the oil to contact the drum for cooling purposes.

It actually kind of baffles me that they don't have any literature or data that states what type of clutch this is supposed to be, because it almost seems like it's both and neither.
 
Yeah, but also bear in mind that I don't have one of these engines and no first hand experience.

The design of the "gear box" is to have a small amount of oil mainly there for the benefit of the bevel and counter gear that would be the clutch gear on a normal engine. The picture of the covers provided leaves an open space for oil to get into the clutch area.

That said, I know the oil capacity is about 200ml, which is basically just enough for the oil to contact the gears and get circulated. The clutch drum also faces away from the engine. This leads me to suspect that the clutch isn't a true wet clutch, but is not fully dry either, and they may rely on the oil to contact the drum for cooling purposes.

It actually kind of baffles me that they don't have any literature or data that states what type of clutch this is supposed to be, because it almost seems like it's both and neither.
I assumed it wasn't a wet clutch, but I never checked. What you brought up makes sense, a little bit of oil in the clutch to keep is cool.
 
I assumed it wasn't a wet clutch, but I never checked. What you brought up makes sense, a little bit of oil in the clutch to keep is cool.
I made the same assumption, but looking at a pictures of the clutch drum/bell made me second guess that thought.

They have 2 small holes at the back of the drum on the outside 180 degrees apart. That screams oil drain-off to me.
 
If it is indeed a wet clutch, or at least a partially wet clutch, then skipping or other engagement issues would likely come down to the type of oil used in the system. Much like a motorcycle clutch, if the oil used has friction modifiers or is of the wrong viscosity, slipping issues would ensue. I am not sure what weight of oil they recommend for the BT80, but I would aim for a 4T type oil with a JASO certification, or at the very least use standard oils and avoid words like "efficiency" that indicate a modifier package. Standard store brand oils like Supertech are actually wet clutch safe.
 
If it is indeed a wet clutch, or at least a partially wet clutch, then skipping or other engagement issues would likely come down to the type of oil used in the system. Much like a motorcycle clutch, if the oil used has friction modifiers or is of the wrong viscosity, slipping issues would ensue. I am not sure what weight of oil they recommend for the BT80, but I would aim for a 4T type oil with a JASO certification, or at the very least use standard oils and avoid words like "efficiency" that indicate a modifier package. Standard store brand oils like Supertech are actually wet clutch safe.
I used 10w 30 non detergent.
 
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