K&L pilot jets for KZ550 F1

Howdy,

I just got a K&L carb rebuild kit for an '83 KZ550 F1, took the carbs out and am now comparing the replacement parts with the original. Just in case

One of the problems I've been having recently is bad throttle response in the pilot jet range (1/8 throttle). Well, in comparing the old pilots with the new, I've found that K&L didn't stamp their pilots with a size. The stock pilots are severely clogged but are clearly stamped with a "32." I was able to get one of the old pilots clean and sighted down it, with a new pilot next to it, to compare jet sizes. Well, they appear to be the same size but...

Another discouraging thing is the label on the carb kits themselves "for zx550a 84-85." The pilot sizes listed in the Clymer vary by 2 between my bike and the ZX500 (they don't even list a ZX550). Meaning: stock size for my F1 is 32, while stock for the ZX is 34. The small drilled holes on the shaft of the pilot are clearly larger on the stock pilot. So, after all that, my first question is this: would you recommend using the new pilots or cleaning out the old ones? With smaller holes on the pilot shaft, will the new ones noticeably affect performance? Is it safe to assume that the pilots in the kits are 34 and not 32?

Thanks,

Andrew

An addendum:

These kits (part no. 18-2461) are what Z1 Enterprises sent me based on the bike's year and model. Ebay stores also have the same kits and the F1 Spectre is on the list of applicable bikes.

Cheers

Definitely use the pilots from the rebuild kit. Regardless of what you may think, it isn't really all that easy to clean old pilots out. Generally, you need a special tool which is essentially a set of wires with serrations on the edge. These things act as a small file and I am sure when you use them, it opens the pilot hole a tad anyway. The stock #32 pilots on your bike are a shade to the lean side anyway, and the bike will start easier and warm faster with #34 pilots. If the bike idles quite a bit; such as the place where you live is chilly and you need to warm the bike up before riding, check the plugs to see if they soot up. If they do, see our website for the "Coil Repowering" mod listed under wg's Tech Stuff Index.

Thanks for the advice WG.

wiredgeorge wrote:

The stock #32 pilots on your bike are a shade to the lean side anyway, and the bike will start easier and warm faster with #34 pilots.

The thing is, I'm not completely convinced that the new pilots are #34's. Like I mentioned before, they have no stamp on them. Also, the diameter of the drilled holes on the shaft of the pilot is smaller on the new guys. If they are indeed #34's, shouldn't ALL the holes drilled be larger than the stock pilots?

I wish I could attach a pic. Know what I mean, though?