Looks like my shoes are not making full contact with the drum. Cause for concern or send it down the road?
I don’t think it’s anything to worry about. Let’s take two things into consideration with their clutches. Once fully engaged, they’re at a 1:1 ratio between the shoes and the basket. And, if you look at the manufacturing…it’s not like they’re high precision units. By that I mean, the way the shoes slide into the center cross hub, there’s a few thousandths play. The baskets are stamped so there’s more inherent imperfections in the design. As long as it’s engaging properly from a stopped start leaving the pits, Send It. If set up properly based on springs used it shouldn’t slip throughout the run. If it does, it’s probably contaminated with chain lube or an over greased bearing.
I’ll be doing standing starts, I should have mentioned that. Sounds like it’s fairly typical wear though.
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Judging by how deep the lateral grooves are, are these fairly new shoes? If so, they’ll probably just wear in, and you’ll start seeing more and more surface contact as they wear.
Yeah clutch is pretty fresh and probably has under 25 “cycles” on it at this point.
@KartingIsLife looks normal for a new shoe that isn’t bedded in yet. Tolerances aren’t great in these.
Some people get a bedding kit to speed the process up. We haven’t done that.
Rough surfaces up with sandpaper, clean the grooves, wipe down with WD40, and send it.
The roughing up helps keep the shoes from glazing and getting slick. The grooves give somewhere for metal to collect and helps reduce galling or scoring of the surfaces. The WD40 isn’t a strong lube and has some solvent in it, so it won’t stay long once the clutch heats up. It’s what Hilliard calls for in manual.
We do our clutch springs after every 2 club weekends or 1 big regional weekend. And we rough up the surfaces after every club weekend and between days at regional events.
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Thanks. I’ve been periodically scuffing the shoes and drum although avoiding WD40 since I end up cleaning with brake cleaner anyway, sounds like the WD is a breakin recommendation though?
Wonder if a little lapping paste would help things 
Maintenance instructions straight from Hilliard.
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