Change the spark plugs if needed. Fine tune with turn increments to find the optimal point that satisfies you. Carb for SYX Moto 50cc Holeshot - Chinese Motorcycles - ThumperTalk I did it to hundreds of cars during my 25 years as The Emissions Guy. How and Why to Adjust a Holley Carburetor Accelerator Pump Replace the fuel pump and verify that the engine starts now. Brand New. This may be caused by a number of different issues, but often the problem can be traced back to an incorrect adjustment of the accelerator pump system. Mechanical secondary Holley carbs (right) do require a secondary accelerator pump circuit since the secondaries can open even at very low engine speeds. Lets assume that we have a small-block engine with an aggressive camshaft, moderate compression, a single plane intake manifold and a one-inch spacer added between the carburetor and the intake. If it does go out of adjustment lots of things can happen. If your scooter is bogging out when you turn the throttle, it may be because of a problem with the carburetor. 50cc scooter carburetor problems can occur for a variety of reasons. Please note that each time the pump cam is replaced, the pump arm clearance must be verified. Her articles have appeared in "Bowhunter" magazine and her poetry in anthologies published by the Library of Congress. The most common cause of an annoying off-idle hesitation on Holley carbs is when the primary bowl has been removed and re-installed. Carburetor Adjustment Screw Adjust Idle Up OR Down To Keep The Atv Running Easily SaferWholesaleCom 58.3K subscribers Subscribe 244K views 5 years ago Carburetor Adjustment Screw Adjust Idle Up. {v0uE*G U[(mk8vo k;GY>*>:;+*5N I agree to receive emails from RacingJunk.com. There are a few reasons why your 50cc scooter might not be able to take off when you give it gas. If the scooter is not starting, it might be because of a problem with the carburetor. {Y U5*oim'>giU~r\:t sB{B ')1|sIJrN!57e,V/qVF~j+Bq 6 h9m:p!G,ixui`qsyW]58IcgC_hV}F}e\}RDX;R46|9kUftL\NgsR^k2\*/=3` v4qs-mu^1+}hB\Q\5|}X]9s?5c50/`#&2/k~sB/ 2J[etK->t u`7);[UjmgZ5 6_ik7O Vl4{J^(sf/L;{9}UYysZ{Ms%I)JdTRINTs2=V}%j% foB,3kzN-/UxCl{[S9I,C}'(1>bkdmb8nwKw9T8xucI *c];\=}'wb_]mSgSRW$4-'je~rN{i7+*aN?7w8+k@6jsi 9*~w~jP"xB&r\*vr%mUc3] S1 Mine wont idle. To fix this problem, remove the spark plug and clean the area around it with carb cleaner. is not closed off ,! On most 150cc scooters, idle speed should be around 1500rpm when the engine is fully warmed up. As you can see, this is a number 40 shooter. Modified on: Tue, May 24, 2022 at 7:59 PM. Many small engines use carburetors to mix air and fuel, and if the carburetor is not working correctly, the engine may not be able to get the fuel it needs to run. Use the rag and carb cleaner to clean it and then clean and inspect all the other parts of the carburetor. This action pushes upward on the diaphragm which forces fuel up through a diagonal passage in the primary metering block, connecting to a vertical passage located in the primary venturi area. 50cc scooters are a fun, inexpensive way to get around town, but carburetor problems are common. 8, Glad you will be doing the adjusting, thanks for explaining what you will be doing. If youre riding a 50cc scooter and notice that the engine is leaking oil from the carburetor and muffler areas, it might be time to take it in for service. In a pinch when a larger accelerator pump nozzle is not available, the holes can be drilled with a pin vise and small drill bit to a larger size.