I purchased a set of Aftermarket levers for my bike a couple weeks ago. Yesterday afternoon I went on a 100 mile ride just around the area with a friend. Everything was great until we were heading back home. At one stop light I couldn't get the bike to down shift lower than 3rd gear. When I went to downshift to second, it didn't even say "1" "N" or "2". It was just a blank area with nothing visible. My options were that or 3rd gear. I just went with it and got it to go at 3rd gear when the light turned green (but barely). I rode for another mile or so and at the next red light the shifting problem happened again. At that time I just cut the bike off, re-started (since I had more time at said light) and didn't have problems since.
My question... is something maybe off with my shifting cable and needs to be re-adjusted, or was I doing something wrong? I have never had this happen before, but I have only owned my R3 since September and I just got my license in May.
Like Kojiro said the only thing that new levers would have to do with shifting problems is if you got the cable free play wrong. The other thing to think about is how/when you are downshifting. Did you come to a stop first, then while stopped start down shifting? Motorcycle gearboxes shift much easier when the wheels are in motion. Even if you are creeping along at 5mph with the clutch pulled in you should be able to select any gear you want easily. Once you come to a stop shifting is much more difficult.
I was having this same issue when coming to a complete stop from 4th gear or higher and I would forgot to downshift while rolling. I noticed while at a complete stop when i would try to select a lower gear it would either be blank or stay in 4th or whatever. This issue was due to me being a new rider and the way I rode....nothing wrong with the bike.
Rc racer hit the nail on the head you need to get all your down shifting done before you come to a complete stop
I asked my dealer and they said it had something to do with how motorcycle transmissions operate forgot the technical details
Next time if it happens try feathering the clutch when the gear indicator is reading blank