Join Date: Apr 2009
Location: Minneapolis, MN, USA
Knocking or misfires at speed
My K100LT is producing some kind of knocking at 2k RPM and above. It seems to idle just fine, but when you give it gas, it starts running rough. A couple of times, it only felt sluggish, with less power, and I was able to keep it at 55mph with a bit of extra throttle. But once, I couldn't even get it to 25mph, and there was a knocking feeling I could feel through the handgrips and my knees, as if someone was rapping the engine with a mallet.
- The bike has always been cold-blooded, needing "choke" to start and idle, even at 50 degrees F (10C).
- I did experience a"power cutting in and out" feeling on it twice last year, both times while riding in heavy rain. I had assumed there was a marginal sparkplug wire, but I pulled the plugs yesterday, and I thought they looked OK (on #2, the insulator tip was white on the sides, but black on the end... weird).
- I suspect that my battery may be going south. This morning, it wouldn't start the bike; I put it on 1A charger, and it was reported as "full" within 3 hours (I'd expect it to need the chargr overnight). But I still have this problem immediately after charging the battery.