Clutching Help Please

[96sherm]

Hi All,

I completed the motor rebuild with the RKTek high compression pistons and 13:1 head. Last night was the inaugural flight. It pulls hard, very hard, but doesn't hold rpm. From engagement to pinned (for short period of time, 15-30 seconds) it will snap out at 8000-8100rpm, but instantly fall to 7300-7400 and slowly climb back to 7800-7950. In snow, (1' of packish powder) it would only snap out to 7300-7600... I have the 10-68g factory flatland weights, stock springs (new in primary). The RKTek kit install instructions say that you may have to ADD 2-3g of weight to the primary...

Can someone, in laymans terms, help me figure out which way to adjust things?

 

[sweld]

I would try installing the weight like the kits says to do before any thing else

 

[Rhodesie]

is it a my 12 or 13?

 

[96sherm]

is it a my 12 or 13?

2011...2500 miles. Some strange testing today... Put my 10-62 weights which would typically be used in the mountains in the stock machine. It ran awesome. Pulled 8300-8400 consistantly, totally rocked my world. My buddy suggested putting his complete clutches on my machine with 68g weights. It ran similar to with my clutches and 68g weights, except this time it wrecked a belt. I put a new belt on and it pulled 8600 which is over revving a bit. Back to the garage and put my clutches on with the "new" belt and my own 68g weights... back to 8100. I'm totally stumped. I don't understand how adding weight would bring the rpm to the "happy" place if it seems to run the best with 10-62 right now... Hoping someone can chime in who has had experience with this stuff...

 

[Jeffpro800]

First thing I would check is your spring rates. Did both clutches have the same springs? Primary and secondary?

 

[96sherm]

Both clutches have been "rebuilt". Primary has new buttons, bushings, pins, and 140/330 spring which is the stock spring. I am concerned about the primary because I took it to the dealer to take apart, they returned it to me with a new bushing and said everything else was fine and within spec. So I wonder about the secondary spring being the problem, helix/rollers maybe? Its tough to get a good feel for it here in Sask with most of the snow being track packed or wind packed. We're heading to the mountains Tuesday, I'm going to take a few parts and hope we can dial it in up there!!