QuestionI recently fixed my motercycle i put a new engine i have a honda cb200t 1975 but when I finished and tryied to turn it on the acceleration was allot so what can i do to bring it down.
AnswerLuis.... Whew... Kind of have to read between the lines here, as I am not completely sure of your remarks or question....
I am guessing that you turned the throttle on and the engine went into high rpms and won't come back down. Right????
Okay! All these things can make the engine go too fast....
Throttle cable not routed correctly, pulling on the carburetor slides. Cable should go beneath the fuel tank on the left side. If you turn the handlebars and the engine speeds up, then you have to adjust the cable routing. Make sure that the cables are all securely in the tops of the carburetors. They can jump out of the adjusters and sit on the top edges, raising the engine speed a LOT!
Carburetor slides not in all the way in carburetors OR are in backwards. There are LEFT AND RIGHT side slides. The cutaway part needs to go to the air cleaners! The slides must sit all the way down inside each carburetor. DO NOT FORCE them into the carburetor bodies. There is a slot on the edge of the slide and a matching tab inside the carburetor slide bore. Check this with the air filters OFF the bike.
Ignition timing not correct, either idle speed timing or spark advancer timing. If spark advancer is stuck open (mechanical part on end of camshaft, behind point plate). Should be able to turn it with your fingers and have the spring tension return it to full retarded position.
Timing needs to be set to that the points open at the F mark on the flywheel alignment. Maximum gap is about .014"
Idle speed screws are set too far in, raising the idle speed. Carburetors have idle speed and idle mixture screws on the bodies. Mixture screws are towards the front of the carburetors (turn out about 1 turn to start) and idle speed screws are in the middle of the bodies. Back out idle speed screws and watch the slides open and close with the air filters off. Turn screws in until you just see the slides raise up very slightly on each side.
Any vacuum leaks between the carburetors and the cylinder head, at the O-ring seals will cause poor idling performance.
Make sure that the valves are adjusted correctly at .002" COLD on intake and exhaust valves (compression stroke) and that the ignition timing is set properly FIRST before you start adjusting the carburetors.
Bill Silver
