440 cyclone clutching (ovals)

[liquidator76]

I was wondering if someone could point me in the right direction for clutching a 78 440 cyclone for a half mile snow track, fresh engine , stock porting dual 34mm carb set up to 78 440 lf specs, as of right now I am running a comet 100c, silver spring with "u" weights that are 63 grams, stock secondary with a blue spring set at 11lbs, I believe they are 46hp at 6750 rpm , I have done a little research from what I gathered depending on the weights using in a gold, purple, or silver are right around 4800-5200 engagement, I know the lighter the weight the faster they will shift but my question is where do I start for weights something with a quick shifting profile

like an a1,r1, or ab1, I almost thing I remember seeing a silver spring with r1 weights was a good combo on the 76-77 440 lf's

Thanks for any input fellas

[air mechanic]

The lighter the weights, the higher the engagement for a given spring. I'm use to "cats" so lots of helix and spring options for the secondary clutches that you don't have with Deere. Not a clutch man but rule of thumb I believe is primary clutch you set engagement,secondary is shifting. Its a balancing act,and thinking your limited on options for the secondary. A heavier weight will shift her up quicker. With twin carbs,not sure how these compare in porting to a Liquifire but thinking I would shoot for 6800-7000rpm peak. 1/2 mile will let her run up some,getting near top out maybe,other thing is gearing. Hope you have a field or lake for testing,welcome to racing! Write down your combinations as you go,trust me you will not remember all you try after awhile.