TOPIC:

DoctoRot wrote: It could be a timing issue. Check your advancer to see if it’s rusty

This? I cleaned this up and it moves freely. Now I am getting popping while idling.

Here is a link to the popping out of the exhaust once it is warmed up just so you have an idea of what I am hearing.

photos.app.goo.gl/qJWArFeGT6xXqAw98

hard to say from the video. If you cleaned the advancer and it got worse I'd verify the timing is good. You shouldn't have to mess with and electronic ignition once its set, so the state of the Philips screw on the ignition plate is a bit alarming. check it with a timing light and make sure its advancing correctly.

I have an 82 750 twin and feel your pain, the intakes and air ducts are extremely hard to find. You'll see an airbox on ebay from time to time but the filters are hard to find too. K&N still makes one though. Took me over a year to find one new duct and I paid alot for it.

My intakes were also leaking a little where they meet the head, fortunately they were in good shape and I was able to clean them up and reseal with some Hylomar/yamabond type sealant to the head. Here is my thread on that.

www.kzrider.com/forum/2-engine/610292-ca...ant-to-cylinder-head

I did find some silicone hoses on eBay that work for intake ducts from the airbox. I will run out to garage a little later and get a pic. The pilot circuits on those carbs are tough to get clean, you really need to be through. MY bike ran absolutely horrible until the intakes were sealed up and the carbs were thoroughly cleaned. Followup with a running sync and a colortune.

That popping at idle doesn't sound like a timing issue, as previously mentioned the timing is not adjustable (although it looks like someone thought it was or removed the pickups for some reason). In my experience that popping is caused by a lean mixture. Are your mixture screws accessible? Any work done on carbs? Not having the stock filterbox etc. will cause some issues with stock jetting.

I think timing was part of the issue. It would pop out of the carb on throttle. After I cleaned it up it does not pop on throttle. Also, there is no leaks at the manifold now.

I don’t think there is any carb work done. I’m going to pull the carbs off again today. What should I do if the mixture screws are accessible?

Stuck or sticking advancer will definitely cause popping and hesitation off idle as you've described. Glad you got that sorted.

If the carbs were ever properly cleaned, the "plugs" on top of the screws will most likely be removed allowing you access to tune the pilot mixture. If the popping is caused by a lean condition, you can richen the mixture to address it. There are multiple ways to do this, I use a colortune but you can also search up "idle drop procedure" to set this. Fuel levels are important too, only takes a few minutes to check them.

So this is the idle fuel mixture screw?

Stop the freaking presses. I pulled the carbs off to thoroughly clean them and I found a missing washer! I guess this could be contributing to the problem.

I'm not sure if that washer missing will cause any issues, I could be wrong though. Maybe someone else can chime in there.

Based on the looks of those jets, that carbs could probably use a good cleaning. The pilot circuit on these can be a pain to get completely clean, I've attached a diagram below that is close (the transition holes are on the bottom of your carb, this pic has them on top). Basically you need to cover different parts with your finger etc. and force carb cleaner and then air thorough all the passages. Start with covering the air jet (lower left when looking at intake side) and blowng cleaner up the pilot jet hole (with jet removed). It should come out of the transition holes. Then cover those and force cleaner again and it should come out the pilot mixture hole. Keep doing this and alternating and you'll get it clean.

Update: I cleaned them the best I could. I am getting some very erratic idle issues where it will jump to 4k rpms and then die. I tried to take it a ride around the neighborhood but couldn't use the throttle because it would bog down. So I removed the carbs again and took them to the shop to have someone else look at them.
His first thought is there is something wrong with the plunger. We shall see.