Hey again, back with more newbie questions. With new belts, I'm comfortable using the 5/6mm allen key method (2v motor), but I feel pretty confident that setting an 'old' belt to the new spec tension will degrade the belt more quickly than it should. Is there a revised method for tensioning belts after re-install? The frequency method seems to suggest 90-100hz, but there's also some confusion about where exactly on the belt to pluck.
Secondly, got an odd issue: Horizontal cylinder is running lean, vertical cylinder is running a touch rich. Seems about backwards from the norm. Only relevant mods are slip ons, iridium plugs gapped to .9mm and CCW coils, with no PC3 even though I'd like one. I'm inclined to believe this is a throttle body sync/idle air screw issue, as it was running slightly rich on both cylinders before I decided to tinker with those two things. Throttle butterflies should be synced (at least, closed to roughly the same degree at the same time?), and the idle airs are both pulled out 1.5 turns. Idles pretty well at 1050-1100, but obviously something is amiss. Thoughts?
edit: turns out the idle air wasn't as I remembered. Horizontal screw was at 2.5 turns (180 degree 'turn'), vertical was at 1.5. Brought it down to 1.5 on both.
second edit: Using Gates' Carbon Drive app, I set the tension to 90hz on the horizontal cylinder and 85 hz on the vertical cylinder, plucking between the cam pulley and the intermediate (non-tensioner?) roller while at the cylinder's TDC. If I push down on the belt with light-to-moderate force, I can slip a 5mm key between the belt and tensioner roller on the horizontal, and a 6mm key on the vertical, both with ease. Without pushing down on the belt, it is somewhat more difficult to do so, requiring some force or two hands (ask me how many times I scraped my knuckles on that oil cooler line). The frequencies all seem to be good, and I can rotate the belt (at the same point used for the frequency) to about 45 degrees. This procedure sound about right?
Which bike/motor?
Sorry, thought I had mentioned that. Bike's an 02 M620.
You can go slightly tighter on a used belt.
You need to sync comparing the vacuum in each TB.
Optical or mechanical sync will barely get you within shouting distance.
This covers a lot mote, but it's got the sync setting info:
http://bikeboy.org/ducati2vthrottleb.html