Topic: CB500 Carb needle clip position question

[Flyin900]

I am doing a cleaning on a set of #627 CB500 carbs that a friend recently acquired on the bike with a POD filter set and an aftermarket exhaust.
He is putting a stock air box back on the bike and possibly keeping the aftermarket exhaust.

The stock main jet is supposed to be a #100 size and the Keihin jet in there now is a larger #105 size. The correct stock needle clip position is 3 down from the top. The current position is 4 down from the top, so a richer setting along with the larger main jet.
The slow speed jet is a #40 which is the correct stock size, so no changes made there.

The question is take the needle clip back to the #3 stock setting with the stock air box or move it one notch higher to the #2 position to compensate for the larger #105 main jet vs the stock #100.

He will not be interested in farting around with different needle settings on these carbs to try and dial this in after my work is done.

So what are the thoughts from members who are knowledgeable on carbs in general, with some real world experience please.

[jonda500]

I would leave them at #4 or if you know it was running rich in the mid throttle range #3. Both my 500's with original air cleaner and exhausts have the needle clips at #4. The jury is still out as to whether #3 or #4 is the original clip position?
John
ps with #105 mains, #4 clips, #35 pilots and air screws 2.5 turns out my resurrected to all original 500 runs very well (albeit very slightly lean idle circuit as it is rich with #38's).

[Flyin900]

Thanks John for the info on your set up.

I see your in Australia and I am in Canada, so there are possibly some differences in the gasoline mixtures between countries. We have 10% ethanol in our regular 87 octane gas, while our premium 89-91 octane can be found with no ethanol in the mix.

The specs I have found show a stock setting of a 100 main jet, a 40 slo jet and needle clip 3 from the top. This is for a general export bike on that model using those model 627 carbs.