One of the simple pleasures of a new bike is that satisfying clunk as you let go of the throttle and it snaps smoothly shut. But that’s not the whole story. While visiting with Honda’s Eric Crippa, he said, “People will twist the throttle, and when it snaps back, they say, ‘Oh yeah, it works fine.’ But put a load on it. Put pressure on it with your hand like you are when you’re racing, then try and turn it. That’s when you see the real story.”
Of course, Eric has been wrenching on motorcycles for¿well, pretty much forever, scoring a title as far back as 1976 with Kent Howerton as his rider. With that kind of history, you know he’s got a couple tricks up his sleeve, and he didn’t disappoint. Here’s how he keeps the throttles on his bikes working smoothly.
“Usually if you turn the bars in one direction or another, you can create enough slack that you can remove the throttle tube without having to disassemble the housing. After loosening the bolts I take the throttle tube off and put some grease and a squirt of lube on the inside of it.
“But before I slide the throttle tube back on, I also tear up a bit of a paper shop towel or something similar, wad it up, and push it into the handlebar with a long t-handle wrench. That way, even if you crash on the left side of the bike and tear the grip, it prevents dirt from traveling through the bar, and messing up the throttle action.
“After you’ve got your lube inside the throttle tube and the wadding inside the bar, you can slide the throttle housing back into place. I hold the throttle tube and throttle body together to take up all the side-to-side clearance, slide it all the way onto the bar, then back it off 1-2 millimeters so the throttle tube has enough clearance from the end of the bar that it won’t stick.
“Once you’re finished, you’ll find that it makes the throttle a lot smoother, and for a longer time.”
Here’s one more tip from Eric about centering the bars (for really fussy riders). “When I center the bars on the bar clamps, I take the thickness of the throttle housing into consideration, and may nudge the bars slightly to the left. That way your grip position is really centered. A technical rider can feel it if they’re not properly centered.”