TOPIC:

That's a fair point Ed and well taken. I will be doing my points tomorrow if all goes well. And my carb tuner just came in as well so tomorrow should be a fun day.

Update:

Got the new points and condensers installed, took my time and carefully set the timing. Got it so 1/4 are right on the F mark and 2/3 are slightly to the left of the mark (after F in rotation). Still didn't start up, so I checked for spark.

3 has a nice spark right between the gap. 4 has faint spark and it looks like its coming from under the node/cylinder. Is this what it means if a plug is fouled?

Backstory: when I did get her running for a bit last week, it was running very rich. Black smoke out the exhaust. After a bit of adjusting the fuel mix screw and idle screw, I got the mixture healthier. This must have gunked up the plugs pretty good right? Should I replace or try cleaning them?

I was able to start it today after replacing the plugs with new ones, rechecking the ignition gaps/timing. I tried to really get both 1/4 and 2/3 firing right at the F mark but whatever I did I couldn't. If I set 1/4 exactly on point and I maxed out the adjustment on the points bracket so that 2/3 has the most amount of adjustment, The best I could get 2/3 was about 2-3mm after the F mark. Not sure what this means? I max out the bracket on the 2/3 as well and it seems like its not enough.

Anyway, I was only able to get it started by backing out the fuel mixture screw (making it more rich). I had the choke at about 3/4 and throttle closed. When I had the mix screws in (leaner) you could hear it trying to turn over and it was close but it wouldn't go.

At this mixture, it's running very lean, lots of smokey exhaust and even some sparks out the exhaust. Also, my idle is very jumpy which I think is because carbs need to be synced. Why does it have to run so rich to start? I'm thinking that the air ratio is too high, but maybe syncing it would help? Maybe just one or two of the carbs are causing a very lean mixture ? Any thoughts welcome!

The KZ650-B1 points plate should look like the one pictured below. It should have plenty of room for adjustment because not only the entire plate can be rotated but also each set of points can be further adjusted. If yours does not have the two adjustment places pointed to by the arrows someone has installed a later points plate.

Regarding startup - the choke should be opened most of the way when the engine is cold. As it warms up the choke lever should be pushed down into the closed position. After the engine is warm the choke lever should remain closed when starting and running the bike. Ed

Hi Ed,

Yes that's how my plate looks. I will try again tomorrow but I did play with the secondary adjustment per point as well. I maxed out the left one rotated clockwise so its sitting on the bottom of the adjustment oval. I did this to try and give myself as much adjustment room on the right points. When I had my multimeter hooked up I was not getting any reading at the F mark no matter how much I adjusted the right points alone. Ill try again tomorrow by maxing out the left points the other way, timing the left points perfectly then I should see a significant difference in terms of what position I get a reading. Will try.

I had choke on full at first, and then I was just trying different positions of choke and throttle to see if I heard any difference. The main difference was made by backing out the fuel mix screws. Why would it need to run so rich to start? Does that indicate carb might be way out of sync?

I doubt it would be sync. The pilots may not be clean. Pic of the bike?
Steve

Hmm I had the carbs and jets cleaned and new gaskets installed. I have pics and what I've done so far posted here:

kzrider.com/kunena/11-projects/611623-77...0b-restoration-build?

Pilots may be too lean.
Steve

You were right Ed, I had to play with the ignition plate for some time but I finally got it exactly right. I get the points firing right at F. I've charged the battery, it shows 13.5 V, points replaced, ignition timed, gap set, choke full, fuel mix screw 3 turns out, carbs cleaned and rebuilt, new spark plugs. Still doesn't start. What am I missing? Whats next to try?

I think I'm going to go grab some starter fluid and spray it in the air intake. If that starts it up then I have a fuel problem right? Probably need to try cleaning the carbs again?

Tried a couple things today. Starter fluid in the air intake sputtered the engine a couple times but not much and not reliably. I then noticed my carb slides were very high, I thought they were set lower than that. Since I think the leanness is the issue, I dropped the cylinders down. Even at the minimum position I had probably about 4 mm gap, which was significantly lower than before. After setting all four to the lowest setting, still no luck starting but it was sounding a bit better.

I then did a spark check/compression test. These new sparks are again fouled... 1 of them have some spark but its crappy, 2 of them have no spark at all, and the last one is grounding itself, spark never reaches across. What makes the sparks foul so fast? They're all wet and black.

My compression test surprised me, I was happy to see 125 psi on cyl 1 and 2 and 130 on cyl 3 and 4! (I did the test with all plugs out, throttle wide open).

So I can rule out compression as a problem. Timing is set properly. I've richened my ratio. I can try new spark plugs again tomorrow but before I do is there something else I should look at?

Are the coils switched? I've done that.
Steve

I hope not! How can I ensure the order is correct? Both coils have wires labelled 1 and 4 so I guess previous owner replaced the 2/3 one with a 1/4 but they should be the same right? How can I test to see that the wires are ordered correctly?

I will check the resistance of the coils today and see if I find anything interesting.

Also, if the coils were switched, would it have started at all? I did get it to start twice on brand new spark plugs each time, and all four cylinders were running because the exhaust was hot on all four. Doesn't that indicate the coils should be working and ordered correctly?