The Rattlers we had experience with had .0015"-.002" interference fit, which is what all other aftermarket balancers have including the OEM ones, so they were not too loose on the snout. It was an inherent flaw with the "rattling" of it as it was in operation that was causing the galling of that brand. They gave us two dozen of the first batch they made, but we never used them, Headrick finally threw them all in the dumpster after we had them for a couple of years and saw all the problems others were having with them. Even though we helped TCI in the prototyping of them, Headrick didn't think the design was going to dampen much, they still are basically a solid balancer with metal slugs loose inside of it, kinda' like the balls they put into tires that you can't balance with normal techniques. That concept might work for tires, but it doesn't for cranks!
