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Discussion Starter · #1 ·
Removing pebbles from tire tread reduces 4C's propensity to clench the dampers in response to minor bumps.

Today they were fuller of pebbles than I've ever seen, and removing them helped more than ever. (Beats me how people with Rs drive on studded tires.)

I even got a machine to semi-confirm my perception today. I was pulling pebbles before the the wheel+tire assemblies went on the road force balancer. I was being pretty meticulous about it. The first read 7 lbs of road force before balancing and 7 lbs after. The second was the same. The 3rd read 10 lbs before balancing and 10 lbs after.

But the 4th I only got all the big pebbles out; there were still little ones deep in the sipes near the shoulders that are barely more than slits. But the machine was ready and, well, how could it matter that I hadn't gotten every last micro-pebble? Well, the balancer said 14 lbs of road force. So I decided to minimally interrupt the process and take the opportunity to do a little impromptu experiment, and hurriedly removed most of the tiny pebbles embedded within the slits (with the assembly still on the balancer). A respin indicated 12 lbs (the only before/after difference seen across 4 wheels+tires).

I maintain that if the road force balancer can feel the difference even just from teeny tiny pebbles embedded within tread sipes that are barely more than slits, with the rubber an/near room termperature, so can 4C... (So imagine the effect on tire roundness/uniformity of big pebbles in the tread, when the rubber is colder/harder and less flexible...?!)

So if your 4C is being a little extra rough on you lately, thoroughly/deeply clean out your tire treads -- eveidently this is a not-insignificant part of R maintenance, especially when it's cold out.
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