Don't panic!
Just roll them back from each end in turn and thoroughly rinse underneath. Just like your Momma told you.
As long as you use something water soluble to get them on you're ok.
Not had Balders problem even in torrential rain but if they keep slipping; how about a few tiny drops of silicone sealant on the throttle side grip?
silicone sealant on the throttle side grip?




