Noise from A/C
Tourer
Joined: Dec 2007
Posts: 265
Likes: 14
From:
When you run a big cam you have a lot of overlap which causes the intake flow to reverse during idle until a RPM that doesn't give it enough time to get to the carb. This is called reversion and is why when you lug the engine fuel will get into your air cleaner and drip on the bike. When the reversed flow hits your carb slide it pushes it out and then the flow reverses and it pulls it back and causes the clack.
On another note, if you're not running tapered push rods and you're getting some clicking try drilling or reaming out the push rod tubes. IIRC it's 13.5mm. When they swedge the ridge for the o-ring on the top of the tube it shrinks the diameter slightly. By drilling this out and countersinking the bore then moving your rocker assembly around to center the push rods you can eliminate the clicking. When I had this problem nobody made any tapered rods.
On another note, if you're not running tapered push rods and you're getting some clicking try drilling or reaming out the push rod tubes. IIRC it's 13.5mm. When they swedge the ridge for the o-ring on the top of the tube it shrinks the diameter slightly. By drilling this out and countersinking the bore then moving your rocker assembly around to center the push rods you can eliminate the clicking. When I had this problem nobody made any tapered rods.
Advanced
Joined: Dec 2010
Posts: 53
Likes: 0
From: North Bend, WA USA
I agree, I have discovered it is the throttle plate on the FBW bikes. The sound is masked when using a stock a/c but when using a hi flow a/c the sound becomes more pronounced. Even more so when a cam is installed. The throttle plate does not open until you hit 2500-3000 rpm. When it finally opens, the clacking sound goes bye bye.
). Anyway, any thoughts are appreciated - thanks!
Thread
Thread Starter
Forum
Replies
Last Post
