I've used nothing but tubeless tires on my Triumph for a really long time. I've had several flats on the rear with no rim lock, and it didn't even break the bead. I was able to ride on it, those tires are so stiff even without air. I think if I were running the original tube type tires that would be a different story.
For the same reason a front-tire blowout is more dangerous than a rear-tire blowout
A blow out is a blow out, David, whether the wheel is balanced or not. The effect of a blow out, front or rear, has nothing to do with the wheel being balanced or not.
So you did not answer my question: Why is wheel balancing more critical on the front wheel?
The only reason might be: There is more mass in the rear suspension than in the front susspension. So the effects in te rear will be less transmitted to the bike / rider than in the front; where in the front the effects will be transmitted directly to the steering bar / hands of the rider...
No arguments for or against the use of rim locks, since balancing is not more or less complicated with or without. The only difference is you need a bit more weight on the oposite side of the rim lock.
back in the middle ages, i took off the steel rim from the rear of my T120 and replaced it with a shouldered borrani. on the advice of the clymer bonneville manual, i dumped the rim lock and just drilled the borrani for four sheet metal screws on each side.
been okay for a long time, but i can't recall whether i've ever had a flat with it or not. i always run new tubes whenever i change tires, and so far perhaps i've been luckier than some.
at 69 i still change my own tires,,,dont use rim locks any more,,,they only throw your tire out of balance,,,dont need them ----if you dont do wheelies and slip the tire on the rim,,,,,if you are using K70 tires,,,they are soft as mush when they deflate on you,,,cant ride them home,,,-----switch to a good firm tire like harly uses,,,,the wont squish and throw you------even K81 are a lot stiffer than K70