2005 Vulcan 800 Engine Noise - normal?
OK all, I got this 05 Vulcan 800 Classic back in 2010. Engine had 700 miles on it then, but it had sat for almost 5 years. I took it to my mechanic, and he replaced the tank, rebuilt the carb, replaced the battery and fluids and tires, and it was good to go. I had him do all the maintenance since then, and in 2017 I bobbed it out. Hadn't ridden it much because it needed new tires and I have a 2016 Vaquero I do most of my riding on.
Flash forward to this past weekend, when I dropped it off for service and new tires.
I picked up the bike this morning (44 degrees out) and she ran great! Rode on the highway to work (25 miles or so), no issues.
It was about 63 degrees when I left work this afternoon, and got on the highway again, but hit a bunch of traffic. Lots of stop-and-go, low speed, and a few bursts to highway speed. After I got off the highway, at the first lengthy light I sat at, I noticed a noise that seems to be coming from the engine. I've never heard this noise before. It sounds like when a manual transmission's throw-out bearing is chattering, but I don't think it is, since it doesn't go away with clutch engagement or disengagement. Seems to go away if I rev above idle.
I had to park the bike to go to dinner, so I did, but what do you all think it could be? Engine was plenty warm at this time. The valves haven't been manually checked - I was told by my mechanic that you could hear them before they got too far out of tolerance to be an actual issue. I've trusted him with all my motorcycles for the past 8 years, and have never before had an issue, so I trust him quite a lot. I'm hoping it's something simple and cheap, since I have just dropped a ton of money on new tires for 2 bikes and services for the same bikes, and the wife definitely won't be happy if I have to drop a bunch more money to keep the bobber on the road.
2016 Vaquero (mostly stock)
2005 VN800B Bobber (Blue Collar Bobbers kits)