Always have to start with choke?

Hi!

I have had my KZ550 for a year or so and for the first six months or so I had her she started up just fine. On those cold days when I rode I had to use the choke a little to get her started, but not on the warm ones. So after those six months I had to use the choke pretty much every time I started her up. I now have to turn the choke on all the way, start until I get some gas in there (doesnt start all the way), then turn the choke all the way off and she will start. I have cleaned out the carbs and it still does this. I went from the airbox to pod filters and it still does this, no change. Anyone have any ideas?

Thanks!

Alex

Actually, you should have to use the choke a little bit unless it is too rich to begin with.
The current state does not make sense, however. The bike should start with 1/2 choke, no problem, and turning it off completely to start makes no sense at all.
Installing pods leaned it out unless you rejetted to compensate, btw.
What did you do to clean out the carbs, just spray some carb cleaner in them?

Does your bike rev properly? If you need choke all the time to get it to run and opening the throttle makes it die a bit I'd go with blocked jets.
I know you cleaned the carbs but I'd strip them again, just to check you missed nothing.
Good Luck. .

You may have two issues now.

First, did you have an inline fuel filter? If so, was it a see-through type with a paper filter element? Those types partially seal up over the course of weeks, and become problematic with fuel flow. That would explain your original problem.

Second, if you installed pods, but didn't rejet, it will need choke for quite a while during warm up. Then it will still be lean. Pods will require going up about 2 to 4 numbers on the main, and probably up jetting the pilot to 34 or 37 (from 32). And possibly raising the slide needle a notch. These are just starting points for the pod jetting. The exhaust will also affect the formula, so it will probably need tweaking the needle with shims or minor main jet changes to get it just right.

Just for my own information, is it considered normal for the Keihens not to require choke when cold? I sold my 81 KZ750E years ago, but I seem to remember using the choke to start a cold engine.

If a bike starts with no choke when cold on a cold day, it is likely jetted too rich.

As the years went on, emissions got stricter, so bikes got leaner. The 550's are especially known for needing choke for quite a while during warm up. Without it, at part throttle they go very lean. You can jet them to be richer, but only by drilling the pilot jets. Larger pilot jets are not available, so people rarely have the pilots up-jetted, unless they convert to pods or have a vey open exhaust.