1982 KZ440 Single Carburetor Set Up

  Hi Ya'll!

This is my first time posting on this forum. I've been riding for years and have owned every sort of make and model you can think of. All that aside, I recently relocated to Lynchburg Virginia and have been shopping for a new toy since. Well right before the end of 2024 I purchased a 1982 hardtailed kz440 with a single carburetor. It's a little different like me and I like it quite a bit. Through reading various posts about others who have decided to ditch the dual carb airbox setup I've been reading of peoples jet sizes. Mine currently has a 150 main and a 30 pilot. I've read of folks having anywhere from a 170 to a 135 main and a 25 to a 35 pilot. just curious if anyone else might have any insights. As winter is in full swing I haven't had much time to work on the bike other than changing out bars and the headlight, but I'm thinking new jets are in order as when I rode her before winter I noticed a few flat spots and that it just didn't seam to have the top speed I would have assumed with it not being as heavy as it would have been stock.

Anyway hope all is well in the world of kawasaki and two wheels. I appreciate any feedback!

Welcome to KZRider
Next time you post a picture complete the install by clicking the insert all tab .
I fixed it for you this time 
Dave

Welcome from the UK

Welcome aboard.

In all the threads you have read about a single carb conversion, did you find any that ended with, YAHOOOO! This thing runs like a raped ape?

I completely agree with your mindset, to some extent. If anyone willing to take the time and read the post one can see that I purchased the bike with some quirks. With that being said I have had that WOOHOOO moment several times over the years on many different bikes. It takes time re inventing the wheel. I'm well aware I do not work in the R&D department at Kawasaki, or any motorcycle manufacturing facility. The purpose of my post was partially to see if there were other people who had experience thinking outside of the box. I may not have stated it out right, but I plan on buying a range of mains and pilots and I'll get it dialed in. Hope yall enjoy your bikes. Ride safe.

There is quite a bit of outside the box stuff around here. Build threads by members like Zed1015, DoctoRot, Wookie58 and others are packed full of really creative stuff. Sometimes outside the box leads to more frustration than joy. Sometimes there are reasons for things to be outside. The single carb conversion seems to be a modification that more often leads to frustration than anything else.

When a new member joins, we have no idea how much knowledge and experience they bring along. Sometimes very little. I have no idea about you, so my intent was to help you get a clearer idea of what you might face. If you are comfortable with the challenge, then by all means plow ahead. The rest of us will offer advice and support along the way.

Personally, I think it would be a real help to the small twin fans if somebody could develop a single carb conversion that worked really well.

I'm unaware of a regular contributor here with a single carb 400/440.  Hopefully, someone reading this thread will have beneficial information, though.  You never know.

Failing that, you would benefit from learning how to perform plug chops.  I'm not talking about riding the bike around then pulling the plugs and looking for color.  Plug chops require driving in certain throttle positions, under specific load situations, where the carb is largely working off a particular circuit (pilot, main, needle, etc).  It can be fiddly time-consuming work.  Good luck with all that.

Edit: if you have a Murray kit, you may want to call them for jetting advice.  They claim their kits are plug and play. 
murrayscarbs.com/product/kz440-kz440ltd-...tor-kit-mikuni-vm34/

I do recall reading several posts/topics related to conversion form dual carbs to single.in the past. As others have said do not recall any indicated it worked correctly. I just did a quick search on this site and returned several pages of posts/topics but it appears that some have lost attachments (pics) and none appear to be from the recent past. It might help to learn just how your conversion is set up. Though my memory is not what it once was, as I recall several were making intake manifold from copper pipe. The Murray set up looks interesting and there are some positive reviews for it.

Depending upon what sort of set up you have it may require more than jetting changes, but what do I know. I would suggest you keep the forum informed on your project and if you find the perfect set up tell us what it is.

Welcome.

While I applaud innovation, fresh ideas, and creativeness, I believe you may be chasing your tail a bit on the one carb thing.

If it had ever succeeded, those conversions would be "the" thing to do on any small twin.

what difference does it make. hardtail motorcycle already modified. doing the carburetors won't matter.

not mine. pic posted here on kzr previously. single carburetor for a kz650.