loudhvx wrote: The only aftermarket support the 440's have, luckily are new diaphragms for the carbs.
Very closely inspect them for rips right near where they attach to the slide. That is often the first area that rips.
If they have holes, that will cause bogging. There are many other causes for bogging, but that is one, and a common one on the 400/440's.
There is a place called JBM industries that makes diaphragms.
Like Moveover said, messing with the airbox or pipes may require minor or major rejetting. You will want to make it run right on stock exhaust and airbox first to make sure there aren't other things going on. After it's running perfectly, then you can try and alter one thing at a time to make changes. That way you will know what each change does. It's a lot easier than making a whole bunch of changes on a bike that doesn't run right in the first place and then guessing which change caused which effect.
I'll echo this. I got my '80 KZ440 D1 as a no-runner of 4 years. First thing I had to replace was the diaphragms. I've been running my JBM Industries ones for a few years now and my bike runs like a dream (after many carb cleanings). As for the pulling the carbs, they're pretty easy to get out. If you've got the stock airbox on, I always undo the 2 screws bolting it to the frame and then pull it backwards after removing the air filter to give myself extra wiggle room. I can get em in and out in less than 10 minutes.
