Continued tuning required!

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Apr 1, 2024
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Wisconsin USA
Didn’t get any more replies on my other post, not sure if there’s a way to bump that one up or not. I got my carbs all balanced nice and evenly, very impressed with the smoothness and response. One area I am not satisfied in is when cruising with the throttle just cracked open. There’s a popping come from the exhaust once the load and RPM’s and load have stabilized. I’m thinking the idle circuit is too lean but I don’t seem to be getting any results going 1/4 turn out at a time on the mixture screws. The only other thing I’ve noticed is it never gets up into the middle of the temp gauge. I know if it’s running cold it will be lean as well. I don’t want to keep messing with the mixture screws if I’d be better off looking at the thermostat. Thanks in advance!
Note that it is a temperature indicator so the needle position on the gauge is not telling you how hot the engine is running.
If you are concerned you should check for correct functioning of the indicator, temperature sender and thermostat.
To check the indicator remove the wire from the temp. sender. With the ignition on the needle should be on the 'C'.
Now earth out the wire and the needle should be on the 'H'. NB Only do this for as long as necessary to, perform the check to avoid damaging the indicator.
The procedure for checking the sender unit is described on p7-50 of the Service manual and the thermostat on p4-8.

If altering the idle mixture screws doesn't affect the condition then that would suggest to me that it is not the cause.
Check that you have the correct PAJ1 & 2 fitted.

Carb Jets.jpg
You could try doing a plug chop when the condition is occurring which may give an indication if it it a fuelling issue.

Also check for exhaust leaks.
Thank you I will verify the sensor and indicator. I should have mentioned in the first post that it has the Dyno-jet stage 7 and a 4-1 ufo exhaust. I did verify while apart that all of the jets and needle clip positions were correct as far as dyno-jets instructions. I just had the carbs off, ultrasonic cleaned and rebuilt them, as well as replacing all of the boots and o-rings between the carbs and heads. I will look It over for exhaust leaks, and what exactly is a plug chop?

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