Bead locks on a KZ650?

this is a new one on me. Getting ready to put new tires and tubes on a 78 KZ650 and I see two of these on the rear wheel. Look like bead locks?

Untitled by j_dvorchak , on Flickr

Yes, they are bead locks; sometimes called rim locks. They are designed to prevent the rim from slipping inside the tire and damaging the tube. Bikes that do not use tubes do not need them, but for bikes using tubes I do not recommend leaving them out even though some folks do. Here's the risk if you leave them out: each time you accelerate or brake hard the rim can slip a little itty bit inside the tire but of course the tube stays tight in the tire and moves with it. However, the tube’s valve stem cannot slip because it is sticking out through the hole in the rim. If the rim slips enough times (maybe a thousand of an inch a thousand times) it will shear off the tube's valve stem and POOF - ALL the air goes out in one fell swoop.

Can this really happen? YES INDEED! It happened to me years ago on my BSA in heavy traffic at about 45 mph when I shifted gears. I can tell you it is NOT an experience I wish to repeat!! My racer friends back then showed me a trick to prevent it from happening again. This involved drilling many small holes around the rim and running short screws through the rim into the bead of the tire to lock the tire to the rim. Thankfully, Kawasaki understood this problem and solved it with the bead locks. I seriously doubt they would have gone through the effort and expense to provide them if they did not consider it to be a safety issue. It may take an extra 10 minutes to install them but considering you don’t swap out tires very often it seems to me the 10 minutes is well spent for the extra protection. Ed

Thank you for the explanation. I am familiar with bead locks and, like you, used to drill and screw the bead to the rim on my old racing bikes back in the day.

Having owned a half dozen or so Kawasaki's, this is the first time I can remember seeing them installed. Trust me they are staying installed and in use if they are in good shape.

I suppose my hands are too big. As I was trying to fit my tires and bead locks at the same time all I was accomplishing was scraping the bark off of the backs of my hands. So I slowed down and built at pair of bead spreaders. They worked great.



Now if I could invent a tool that made installing intake boots as easy as these bead spreaders make installing bead locks, I'd be a rich man.
Bill

Hi KZQ,
We like that! Thanks for posting.

How is the crosspiece retained?

Good Ridin'
slmjim & Z1BEBE

Hi Jim.
The cross piece is just a fulcrum. I just laid the wheel and spreader on the floor, hooked up the "Lips", placed the cross piece wherever the leverage was good, pressed down and placed the loop of tie wire over the ends.
Bill

So when you are doing the tire change you completely remove the rim lock?

So loosen the rim lock
pull the tire bead over the rim and rim lock
pull the rim lock out
put the bottom bead on
put the rim lock in
install the top bead?

I do. When I change the tire I remove everything from the rim and clean it really well. Ed