1977 Kawasaki KZ400, Part 2

I’ve lost track of how long the KZ400 spent on the other side of the shop, collecting dust, before I got back around to working on it. I do know that I finally got back to it on a Monday, eight days before the event I was preparing it for.

The last minute work included some straightforward bits: replacing the fork seals, affixing an Emgo replacement headlight and shell, adjusting the valves, changing the oil and filter, replacing the hand grips, and installing a new chain and sprockets.

The more difficult work included repairing an enormous hole in one exhaust pipe, right up at the cylinder head. A previous owner had apparently applied window glazing putty to the hole to seal it up. I have no idea if that actually worked, but it surely fell out when I bolted the exhaust back on. I had Stan Pugh come by (this was very last minute), and he spent at least an hour welding and grinding and welding again. This was not a “clean” fix, because the edges of the hole were terrifically rusted. But for the Ozark Mountain Scramble, you patch things up well enough that they’ll work for 600 miles, and you cross your fingers. (That was my take on the ethos of the event — others had much cleaner bikes than I.) After welding the exhaust pipe hole shut, we also banged on the muffler to help it clear the rear brake arm. It didn’t take much, and the rear brake could be applied and released normally after that.

I never did sort out why the handlebars and front axle weren’t parallel, but once I proved to myself the bike would ride in a straight line regardless, I left it alone. What I did figure out was a way to hold saddlebags to the KZ400’s original luggage rack. It seems this bike was a KZ400 Deluxe, which came with a windscreen, rack, and saddlebags. Only the rack remained, but I remembered I had a pair of Honda Silverwing (GL500) saddlebags in my basement. They hooked over the rack in two places, then a tie-down strap got them away from the rear shocks, and a few large zip ties held them to the rack well enough to prevent bumps from kicking them off the rack.


A lunchtime road test of the bike showed that it was tracking pretty straight, but the engine wouldn’t idle normally. Instead, once it warmed up, the engine wanted to race to something sounding like 5000 rpm. Sometimes I could bring it down by using the clutch to slow the engine. Sometimes that wouldn’t work. I confirmed the problem was most likely a vacuum leak, then decided there wasn’t time to address it properly. (I recalled the hateful job of putting not-quite-fitting carbs back on the engine and didn’t really want to repeat the experience.)

The same treatment was applied to the clattering cam chain, but less out of laziness than out of fear that removing the cam chain tensioner would expose worse problems. Better to leave it until after my return from the trip.

I never did treat the fuel tank. I decided instead to put gas in it, see if it leaked, and deal with any loose crap in there by adding a small fuel filter to the system. (Keep that in mind for later.)

I did, at some point, put new float valves in the carbs, and those worked great. It’s nice knowing that if you forget to shut off the fuel petcock, you probably won’t come back from lunch to find half a tank of fuel underneath the bike. I also tried replacing the carb holders (rubber boot between the carb and the cylinder head), but the ones I got weren’t a correct fit. (So I did try to resolve the vacuum leak once, at least.)

I never did figure out why the luggage rack looked crooked relative to the rest of the bike. Given the bike’s handling, there’s no reason anymore to think that it was crashed badly. Perhaps it was just dropped, bumped by a car, or generally mistreated.

by Andrew | June 18, 2012 at 12:24 am | Outside Work | 3 comments