os 120 surpass hs-needle
05-30-2007, 08:37 AM
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os 120 surpass hs-needle
While adjusting the high speed needle on my os 120 surpass, I noticed that the more I ran the engine on the bench during break-in, the further the closed-point move toward the lean side. In other words, if at first I closed the hs needle, and it stopped at the 6 o'clock position, the stopping point has progressed in a clockwise manner, to where now it is fully closed at the 11 o'clock position. The engine runs great, no complaints there, but is this normal for the fully closed position to change from the initial point fresh out of the box?
05-30-2007, 10:22 AM
#2
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RE: os 120 surpass hs-needle
What's happening is that the needle is enlarging the needle seat. You may be "closing" the needle valve a bit firmly. You only need a gentle touch. After a while, you'll find that the needle won't allow you to get a proper adjustment because the needle seat will be too worn out...you'll need a new carburetor body at that point.
Generally, the only time you'd fully-close the needle valve would be when you initially set up the engine. After that, you'd almost never need to close it.
Generally, the only time you'd fully-close the needle valve would be when you initially set up the engine. After that, you'd almost never need to close it.
