I bought an '07 Wee with 52,000 miles and it had a bad hesitation problem. The exhaust has been drilled out. I expect that that was causing the bike to run a little too lean, which in turn was causing the hesitation. The hesitation occurred if I was off throttle for about a second and then came back on throttle. No matter how smooth I was, when I came back on throttle it would take about .5 to .75 seconds for power to resume. This made the bike difficult to ride well because there often was no power to pull out of corners. Sometimes power would kick in in the middle of a corner, which wasn't good for a newbie.
I thought I was going to have to purchase a Power Commander to fix the issue, and then a few weeks ago, the problem went away.
Now, I get to apply power to pull out of corners. Also, I think there is more power at lower RPMs. Time will tell, but I think my MPG may be less than before.
Even though I can't say what fixed the problem, I thought I would post my observations.
1. Is the problem temperature or weather related? Since the bike started running better, I have been riding varied temeratures between 30F - 65F and the bike has ridden well in all these temps.
2. Perhaps the bike just needed to be ridden a lot. I have been riding as often as possible and running a mild fuel injector cleaner every tank. Perhaps this loosened up some crud in the fuel injection system, or maybe the fuel filter was clogged. I put about 1600 miles on the bike over two months when it started riding better. I have also done high RPM accelerations. Yes, the so-called Italian tune-up.
3. I changed to Delo 400 LE with AutoRX. AutoRx has been known to clean up rings so they seal better, and clean valve train.
4. Adjustments? When I first got the bike, I adjusted the TPS, but found it didn't change how the bike rode much. I haven't adjusted it since.
I am really glad the bike is riding better and for this forum.