Some of you might remember another thread
where I spoke of the issues that I was having with jerkiness at lower RPM. Well, I've wanted to repost this for a while, but wanted to make sure that I got more info before I did, clear up some ambiguity. Maybe some of our new members have some insight
Here's the problem, again...
In the 2.5-4.5k RPM range, my 919 has issues when constant throttle pressure is applied. Not so much when accelerating, but it can be seen with slow, constant acceleration. The issues are that when held at a steady pressure, the engine will become jerky and drop by a hundred or so RPM for a split second, then back to normal, then back down. This really sucks when riding because this oscillating RPM translates into rear wheel jerk. For highways it's not too much of a problem, because the higher RPM of highway driving doesn't exhibit this behavior. If I go 50-60 on the highway, it does. The biggest thing that worries me is when I'm riding in the twisties, I really don't want the rear wheel jerking around while leaned over...not real safe. Most of all, it makes me less confident in the bike's ability. I thought at one point that it could be a chain issue, but even if it's parked, in neutral, and I hold the throttle steady, the bike will still exhibit this behavior. There are times when it doesn't happen at all in a riding session, but it's a good bet that at any given point, it is happening.
A lot of you have given things to try, so let me tell you what I have tried, and ultimately hasn't worked:
- Drive chain is tight, cleaned, and lubed
- Spark plugs are good
- Throttle free play adjusted (tightened)
- No powercommander in use
- Battery connections solid
- Ground wire to frame has good contact
- Adjusted idle speed
- Bought gas at many different stations, and different octanes
Do I take it to the dealer? I can look at things myself, but I just have no ideas as to what the problem could be. I'm fairly competent when it comes to slinging a wrench, but I don't have much experience troubleshooting stuff like this. I do have the Helm manual, but again, don't know where to start. Any of you pros want to come live with me for a week and get it figured out?
Once again, thanks in advance for any advice.