Walbro are normally preset at 1-1/2 both L and H and fine tuned from there. First make the metering lever is set at the correct height. The W tool makes it easier but it normal even with the small valley it retracts into for the WA/WTA/WT carbs.
Set the L mixture to best idle speed plus a tad richer then adjust the H speed for best top speed but don't exceed max rated rpm. If it wants to do this enrich the fuel to limit the top speed.
Also Walbro has both IPL and service manual for their carburetors at http://www.walbro.com/partsservice
Last edited by AVB; 19/04/15 07:35 PM.
