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Discussion Starter #1
It doesn't take me long before I get the bug to make something run better. My TW is a Calif model and the carburetor seems to surge at light throttle and low RPM. I adjusted the valves today (1950 miles) and while I had the tank off, I went for the carb. I took the black top off of the CV carb and pulled the diaphragm out to see if I could raise the needle a notch. No such luck. I made up a .015" shim to raise the needle. Man...It woke that little engine up! Still has the low speed lope, feels almost lean? Probably the CV carb,

Does anyone have a suggestion on an older style but new slide type carb or remedies for the existing one? I thought about shortening the existing slide spring so the slide raises earlier. MIKUNI for the TW???
 

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No, have not re-jetted. I don't know if the Commiefornia carburetor has removable main jets or pressed in. The carburetor and main is different than the 49 state carb according to the parts fiche online.

I will have to check the low speed air screw. So where do you drill out the vacuum port on the slide? What size drill? I saw a small brass, pressed in orifice at the top of the carb when I removed the black top cap. I DO have some pin drills. Used them alot on old VWs and Porsches.
 

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No, have not re-jetted. I don't know if the Commiefornia carburetor has removable main jets or pressed in. The carburetor and main is different than the 49 state carb according to the parts fiche online.

I will have to check the low speed air screw. So where do you drill out the vacuum port on the slide? What size drill? I saw a small brass, pressed in orifice at the top of the carb when I removed the black top cap. I DO have some pin drills. Used them alot on old VWs and Porsches.


The only difference between your carb and the 49-state carb is the vent port for the canister and a RICHER jet.



If you're loping and/or surging you've got other issues..
 

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Check the stickied carb tuning thread in technical, and do one thing at a time. I'd just about guarantee the idle mixture screw is set way lean.
 

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Discussion Starter #7
Thanks guys. I'll check the idle mixture.


Pulled the carburetor off today and removed the block off plug for the low speed mixture screw. I opened it up about 3/4 turn and got rid of the low speed lean surge. I also put a .020 spacer under the slide needle. Runs good now.
 
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