Rough riding after valve clearance adjustment

'77 KZ1000A

Shortly after buying my bike (a first experience with this type) I started hearing what I thought were tapping valves, and so I decided to check the clearances. Ended up adjusting all four exhaust sides from .006-.008 down to .003-.004 (the mid/higher end of the range according to Clymer).

Got everything back together, changed oil (10w40), and started her up. Things seemed nice and smooth at first (although I did end up messing with the idle screw a bit), until after warming up I started going through the gears and picking up speed.

First symptom is a rough sound starts coming from in the left side of the engine (which I'm hoping just means I need thicker oil, since I did have that side cover off to replace the gasket).

Second, and of most inconvenience, the bike will eventually just stall while rolling off the throttle to shift or slow down. To get going again the choke has to be on and the idle kept high. Then she revs up and once you get going you can turn the choke off and the idle back down, but soon enough things get rough again and the cycle repeats.

I'm also still hearing the original tapping sound, and so it seems I need some advice. Have a go at it.

I'd get the bike on the center stand, and if possible, slightly lean it to the right to minimize and oil loss. Open up the left side cover & look at the magnetic rotor. There have been reports of the adhesive failing, that holds the magnetic segments in place.

Any battery charging problems?

Everything seemed intact when I had the cover off before, but I could recheck it. Was thinking I should go back in there anyway to make sure that smaller gear piece is in correctly.

The original battery (old acid fill style) did have a charge holding problem. The first time I took out the bike and noticed its issues I had to walk home because the battery finally died after stalling and restarting so many times.

But I bought a brand new modern style battery and it's working very well. It just started right up after sitting a few days.

Check your plugs and intake boots.

MFolks wrote: I'd get the bike on the center stand, and if possible, slightly lean it to the right to minimize and oil loss. Open up the left side cover & look at the magnetic rotor. There have been reports of the adhesive failing, that holds the magnetic segments in place.

Any battery charging problems?

Those rotors don't do that. That's the early style charging system with the small rotor that spins inside the stator. It's the later models, 79+ that happens to.

sounds like a carb problem. Is the tank/petcock clean? Inline filters clean?

mtbspeedfreak wrote: Check your plugs and intake boots.

My bike did that when my plugs were fouled very very badly. I had no idea because I just bought the bike. Also, my intake boots were cracked and air was getting in, messing with the air/fuel mixture.

Probably not, but did you in any way effect your cam timing? Maybe pull the tensioner loose?
If you had to remove cams I would say cam timing but if you didnt mess with any of that, your probably ok there.
P.S. Exhaust leaks on a KZ often sound like vale tapping.

I'll check the plugs and intake boots next. When I had the tank off for the valve clearance check I noticed rust, so I cleaned it out along with the petcock before reassembly. Maybe the same needs to be done with the carbs. Inline filter is fine.

Didn't mess with the cams at all, but that exhaust leak bit sounds interesting.

I checked and rechecked the carb holders and didn´t see anything wrong with them until I sprayed them with starter gas. I had also renovated the valves and seats and went down 1 size in 4 places. 3 exhaust 1 intake. But the hose clamps were streched so they didn´t grip tight and until I found that problem and replaced the hose clamps I was going nuts and trying everything that could be wrong with it. So spray the card holders with start help gas and see if the idle changes. If the holders are ok then nothing will happen, if it changes even a little then you might have the problem right there.

daless wrote: '77 KZ1000A

..Got everything back together, changed oil (10w40)..First symptom is a rough sound starts coming from in the left side of the engine (which I'm hoping just means I need thicker oil, since I did have that side cover off to replace the gasket).
...

Thicker oil will not fix anything.

You might want to synchronize to carbs. In some cases, changing valve shims will change the cylinder vacuum on each individual cylinders thus creating a rough idle condition. Don't forget to check the cam chain adjustment and timing too.