One bristle from a wire brush works well to clear jets. And that pilot jet hole is very small. Good job checking them against a light.
You should replace the carb O-rings with new. Cycleorings.com sells a VM kit that will help.
I use the Golan Super Mini fuel filter that TexasKZ recommends - it is perfect. Regarding the fuel hose, I have tried a number of different ones over the past 42+ years and found that the GoodYear 5/16" Fuel Hose SAE 30R7 is absolutely the best. The link below has more info. Ed
It appears you have a set of vm24ss carbs that only have a pilot air screw. To the best of my knowledge all of the carbs (VM22 and vm24)that came stock on the 650s in the US market only those with the pilot screw have the additional #50 jet over, or under depending upon who you want to look/explain it , the the pilot jet.
I removed my years ago and the bike runs fine. I am not really sure why this additional jet was added, but feel that the engineers and designers thought it was needed to to provide a rather logical power band.
Thanks guys! Yes I'm going to replace all o rings and gaskets, I picked up 4 carb kits. I want to clean and reuse the Jets instead of using the ones that came with the kit. But I was curious to see what other jet sizes you guys are running now that I have the option of changing it.
The stock jeting on a 77 KZ650 B1 (VM24) is #16 Pilot and #100 main Jet.
Keyster No.: KK-0041 kit offer a #15 and #102 jets
So with your #112,5 main Jet you are a little rich on a stock air box. Your main jets ( #112,5) is more like for runing pot filter.
The best fuel hose I've found is that sold by Suzuki www.partzilla.com/product/suzuki/09352-70103-00B
Order this PN and they send you about 5' of the stuff. Enough to do several bikes. It's 7mm and stretchy, just like the OEM Kawasaki line. You don't need to use clamps, just slip the line over the nipple fittings.
Car fuel line is much thicker and has a braided inner core to resist high pressure (which KZ's don't have.) 1/4" line is very tight and hard to install and 5/16's is looser than stock and you will have to use clamps too or it may leak.
Thanks, I left the 112.5 jets, makes sense they were purposely changed when changing to pod filters.
Thanks for the hose suggestions! I'm going to order some tomorrow morning.
The only hitch I had was with the pilot needle. I didn't check on the first two carbs how far from fully seated the settting was. I noted on carb 3/4 it was about 2.75 turns from fully seated. I got them snug before measuring.
The manual (like to page in the post above) say it should be set to just 3/4 turns from fully seated... So I guess they were way off before? Going to set them all to 3/4 turn and see how that goes
Be extremely careful with the pilot screws since the tips love to jam in the orifice and break off. This typically happens when someone is trying to bottom out the screw before resetting them. Be sure to spray carb cleaner through all the passages and verify you are getting flow through the small hole and into the carb body. If the pilot screw doesn't turn easily buy a tap and clean the threads. I think it's 6 x .5 but measure for yourself to verify.
I think 7mm fuel hose might be a bit loose on the Kz650. The 7mm would be perfect for the 550 and probably the 750, but I think the 650 uses the same size as the 400 which is closer to 1/4".
From researching the parts over the summer, in the fiche, the 550 hose is labeled "7 x 12 x 180 " which I think is ID x OD x length in mm. So 7mm hose is exactly right for the 550.
The 400 hose is labeled "5.3 x 10.5 x 200" in the fiche. I think that is 5.3mm ID. The petcock outlet pipe OD measures 5.8mm on the shaft and the barb OD measures 6.9mm. So if the Kz650 petcock measures similarly, the 7mm hose will probably be too loose. Of course, you can always clamp it down to make it work.
EDIT: I looked up the part on the Kawasaki site, but the page for 1977 B1 and C1 does not list the hose.
I found the 1979 Kz650 lists two hoses. I think the smaller one is the older of the two and may be what is on the 1977 Kz650.