I gotta think the problem is more aftermarket bars, and their installation than just with the Road King.

 

i had a pair of 16 regular size apes crack like this. mine were also drilled for internal wiring. the combination of that and the small clamps is a bad one. my bars were splitting where the hole was. i rode the bike everyday for transportation and couldnt afford to be down. so, at that time simply putting the top clamp on fixed the torn bars until i could order more.

ive always used the stock harley one piece clamps with no clearance problems. the newer(08 and up maybe) bikes are coming with a one piece clamp now.

head

 

So, to answer:

I got the one-piece clamp from Drag Specialties. Cost $16.95, is chromed, and fits under the cover very nicely.

I, too, thought that the problem might have been that the bars were drilled/slotted. But the indy explained that the bars would not have cracked & busted had the risers been properly tied together. It appears that no matter what your riser bushings are made of, they will flex independently to some extent if they're not tied together.

One thing's certain though...Damned glad we weren't in serious traffic. And thanks for all the good thoughts!

Now I just gotta get the 1 1/4 inch bars to replace the stock ones!!!

 

I went with a one piece top clamp when I installed WO508's on 07RK. I had to counter bore the holes a little deeper in the clamp to clear the nacelle. The clamp was off a Dyna not sure what year.

 

Yeah, I'm basically of the same mind, mostly on the installation side.

I bought the bike second-hand, and the orig. owner had already had the fatter, wider bars installed. It seems that the wrench at the Harley dealer's shop that installed them didn't know to use a one piece clamp, chose not to use one, or they simply weren't available then. In any case, it's most certainly a combination of things that led to the bars failing: Drilled/slotted bars, excess torque due to the width of the bars, and using separate clamps for each riser.

One other thing for those of you planning on mounting a one-piece clamp:

Be prepared to need to squeeze the risers a touch (1/16"-1/8") in order to get all the bolt holes to line up properly. I used a bar clamp to do it, and it worked out just fine.

 

There is no extra torque or stress on the bars or risers due to bars being wider. You push on one side of the bars or the other and the forks turn. Now if the front end was locked so it wouldn't turn then yes, you would be able to apply "excess" torque. The only situation you're going to see close to this would be when you're pushing your motorcycle around in the driveway.

 

I replaced mine with OEM one piece clamp when I put the PYO bar.

 

After reading RK Cal's post, I decided to go ahead and put a one piece clamp on my RKC. I've had beach bars for 10 years and they haven't crack yet, but still...I bought a one piece clamp a while back at a swapmeet for about 3 bucks. It was a stock one from a late model bike. It has an '01 stamped on the back. It also looked just like the stock one on my '77....Anyway, I put it on and put a dab of Goop adhesive under the clamp for extra holding power because my beachs could be moved if you pushed 'em hard enough with the stock clamps, even though they were snugged as tight as I could get them...I broke a bolt when I put them on because I ratcheted them down so tight....Even before the Goop dried, I could tell the one piece clamp held the bars tighter than the two piece...The chrome clamp cover fit fine with this particular clamp.

 

Well, that's perzactly what it was, when you think about it.

What I mean is, the pushing it around the driveway, in & out of the garage, maneuvering into parking spots. Even more so when there's a load of gear or the wife on the back.

Regardless, it did add up!

 

Just a follow up.... I went with the zinc one piece Harley top clamp. The dealer ordered me a set of Poly bushings, ended up being Arlen Ness brand (not a fan but they wouldn't take back special order parts) that were .320 to big for the hole in the triple tree I had a friend mill the Ness bushings down,installed, now I have less than 1/4" of play as opposed to the almost 2" of play before.
Thanks to all for the input and Part #'s