Question about Blade Brake Clutches

Hello all, I don't have much experience with lawnmowers outside of simple push lawnmowers cutting smaller lawns in the suburbs. Lately I've been trying out picking up lawnmowers people get rid of, fixing them up and re-selling.

One lawnmower a lady put curbside was a Craftsman 917.377792, which is a 21" self propelled with Honda GCV160 engine. It's also the first lawnmower I've run into with ball bearing wheels - so a pretty nice one to me.

It also has a Blade Brake Clutch - again first time I'd seen that. I get that you can have the engine running without having the blade spinning, but is that really a big deal? What's the appeal of it in a push mower? Seems like one more thing to maintain.


As a sidenote, when I go to engage the clutch, it's a bit rough - seems to bog down the engine until it's fully engaged and then the engine comes back up to speed. Is that normal?

Thanks.

There is a certain section of the government ( usually creationists ) who believe they can prove Darwin wrong through legislation.
Thus most mowers now have to be set up so it is impossible to shove your hand in the discharge chute and get your nails clipped at the wrist.
Blade brakes is one such method.

Yes, that's what I thinking. Hopefully there must be some mowing application that justifies it. I really like this Craftsman mower (strong rear-wheel self propelled), but would rather it didn't have the BBC.

I had a BBC mower for a short time.
At times it came in handy when having to clear the way ahead of mower such as removal of large debris.
Instead of having to kill the mower, I would simply disengage the blade whilst the engine kept running.
Did not have to worry about restarting every few yards or so which I believe was its intention, and was not a government mandate.
It is not a new or even recent design. First one I saw (and used) was manufactured in the late '50's.

Blade brake or dead mans ignition or engine brake are law
Some even have all.
Some have been fitted for a long time but now days a mower is not allowed to be sold if it can be left unattended with the engine running & the blades spinning.
How the mower companies achieve this is up to them.
Most cheap mowers simply run a fixed throttle with inbuilt ignition switch on a spring loaded handlebar bail, others go a more expensive route.
There is 10% of good reasoning in there but lets face it, if you are stupid enough to leave a mower running at full speed while you empty the catcher or unblock the chute then you deserve to loose a hand or eye