Last year, I had a medium speed lowside where my bike tumbled a bit. The bike ran fine afterwards, with the exception of a very low RPM stumble. Basically, if I slowed down too much for a corner, or didn't downshift enough, when I went to get on the gas, it would hesitate for ~1 second, slowly build RPM, then accelerate normally once the RPM's raised a little. I rode it around the neighborhood a couple months ago and it was repeatable there as well. I'd like to start getting the bike back into good working shape. Where should I be looking to address this issue?
Actually not sure what controls them, so what @DonTZ125 said may already cover this, but I instantly thought of the velocity stacks that go up and down in the airbox. They are controlled by a servo with quite a few moving parts, possibly something is disconnected? I do remember you could hear them cycle when turning on the key.
if the v-stacks are unpluged or for some reason not operating, the bike will start, idle, and run up through midrange perfect. Even if in upward position. You will have dramatically lower power as you try to get higher in rpm range though.. so not likely the issue. Can check your TPS settings and sweep range (twisting throttle) by putting your gauge in diagnostic mode. manual will show how to do this, and give you acceptable ranges for readings that appear on the dash.
Yep stacks were what I thought. Also make sure the teeth are lined up on the gears in there. Mine were off before
without a doubt.. the bike will run like it has half power with em not connected and working ! .. and will say, it's worth a look-see in the air box, who knows what issue is caused if they are misaligned. lots of stuff could have been jarred in a tumble. i'd be going over the bike top to bottom. Something like a temp sensor in the plastic ram air tube in front fairing could be broke (but that will throw a code), stator could be on way out (not making sufficient voltage at lower rpm, not really caused by crash, just coincidence)
Yeah, what Rick said, always start with the simple things. I've had several customers self diagnose stuff and spend hours and hundreds before they give in and bring it to me and it turns out it's just the battery for example.
This same thing happened to a racer friend. Ended up taking out the fuel pump, and saw that it had started to come apart. There are pieces of the pump that are held together by clips and those broke and separated the unit from the housing. Just throwing yet another thing to look at.
for sure easy to check.. just swap out a buddies tank with known good pump. snap fuel line in place, ride in pits to see if has stumble..