KZ550 Project Questions

Since I've already started a few question threads about my KZ550 project I've decided to just start a single thread about it so I don't clog up the forum with my questions.

So, I got some superbike bars for my KZ550 and I've pretty much gotten it all installed except for a few issues.

After replacing the bars, my throttle sticks quite badly. I lubed the cables and it works fine with the throttle off the bars but still sticks when its on the bars. It's almost like the bar is a bit too large and won't let the throttle move freely. Any ideas?

Can you measure the outer diameter of the handle bar and the inner diameter of the throttle sleeve with a dial caliper? This will tell you what the problem is.

The bar may have a weld or paint build up just enough to cause it to bind up.

The problem isn't paint, because the handlebars don't have paint where the throttle grip is (though maybe there is a bit of overlap with the throttle grip, I'll have to check).

I did take a small crescent wrench (the poor man's calipers, haha) and compared the diameter of the new bars to the diameter of the old ones. The old ones are ever so slightly smaller in diameter than the new ones, so that might be the culprit.

If you put new rubber grips on the throttle, sometimes the flange on the thumb end rubs on the throttle housing. Pull the rubber grip away from the housing by a mm and see if that makes a difference.

Did you replace the cables with the bar switch? If your cables are too long you will have a nasty time with friction from long sweeping bends or tight short ones. Release your bars from the hold downs. Then try the throttle while changing the angle of your bar/cables. If they are better at a different angle it's you cables, routing or length. Usually the bar thickness is not the problem. Also some switch housings have a little boss that locates into holes in stock bars and have to be ground off for bars with no locating holes. Pics might help.....

Locozuna wrote:

Did you replace the cables with the bar switch? If your cables are too long you will have a nasty time with friction from long sweeping bends or tight short ones. Release your bars from the hold downs.

I bet that's it! The controls are about 5" or so closer to the center of the bike. I'll have to get under there and see about pulling the throttle cables out to avoid the tight turns.

I actually drilled a new hole in the bars, though I might grind off the little nubbin anyway.

Rerouted the throttle cables and everything's great now.

I'm suffering the same issues that you had. How did you go about re-routing your cables?