Pre rotator clutch performance

[Mike G]

The attached graph shows the rotor speed plotted against the engine speed during pre rotation. Also shown is the theoretical speed ratio of rotor against engine speed assuming a non slipping V belt clutch.
When the actual curve is below the theoretical curve the clutch is slipping. This is easy to see up to about 185 rotor rpm. The theoretical line is calculated from the outside diameters of each V belt wheel which is not really correct.
What's interesting to see is that after 185 rotor rpm (at which point the clutch lever is fully in) the actual line runs parallel to the theoretical line, meaning that there is a constant slip and that it doesn't slip any more even up to 250 rpm rotor speed. From this I can assume that the clutch part of the pre rotator is good for a higher power and speed. I wonder what part is the weak link, I always thought it would be the clutch.

Mike G

[Friendly]

I could not open the file, but I still think the friction drive on a Wonderlich is the weakest point. I can spin my rotors to 260+, but it going to cost me some rubber off the drive wheel.

[Mike G]

Mark
This is a Magni M16, the clutch is a double V belt arrangement.

Mike G

[Friendly]

Do you have some pictures, I like the ideal of belts better than the friction wheel, There is a lot more surface area to work with, but the engagement could be too hard. I am interested in your arrangement.

[fiveboy]

I could not open the file, but I still think the friction drive on a Wonderlich is the weakest point. I can spin my rotors to 260+, but it going to cost me some rubber off the drive wheel.

I wish that were the case with me. I have (apparently) a Wunderlich wheel but the rest is proprietary to AC. Im on my third cable..... this year. They did just change the design of the square end piece that seats into the Bendix so I am

A. Thinking it might get better
B. Thinking it might not have been all me (after all why would the design change if its fine!??)

BTW Im happy if I get 120 anymore

[JEFF TIPTON]

Converted the word document to PDF.

[Mike G]

Mark
I'm not at home at the moment, I'll post pictures next week. It's the standard Magni setup, so perhaps another member has photos.

Mike G