I'm new here, with a question about vibration. I just bought a used 2001 LS650 with 500 miles (not a typo). I just got my motorcycle license, so I'm somewhat new to riding bikes. However, my machine has significant vibration over 20 mph. It feels significant to me, but maybe this is normal for this model.  My LS was in storage for many, years until recently. It was checked over by a dealer before I bought it, and was said to be in good shape. Has a new battery, new carb, but original tires/rims. It starts easily and idles nicely.  Interested in anyone's thoughts.
Thanks much.
Dan
Eagan, MN

At 20 mph, 2nd gear at about 2400 rpm, you shouldn't be vibrating excessively.
1st thing to check out is the engine mounting bolts, if they're loose you will feel more vibration.
Torque values are in the tech section, check out the index link below.

Is the vibration rpm dependent or speed dependent? There is a significant diference.

The LS is a big (one of the biggest) and relatively simple single cylinder engine (aka Thumper). All single cylinder engines vibrate - and the larger the displacement the more they vibrate (there are exceptions...refer to my comment about being simple).

It's not uncommon for riders to complain about vibrations at higher rpms (my bike has a tachometer so I know that the vibration party starts in earnest around 4000 rpm).

If your vibration is rpm dependent it's completely normal for this engine. If however it is speed related I would look first at tire issues (flat spots at the rear or cupping at the front tire) and then suspension issues (blown fork seal, bent forks, broken or bent shock).

The vibration seems to be dependant on rpm. However, at 50 mph I feel like I'm in a coin-op bed that has gone into a high speed wobble. Vastly different from the Suzuki 250 I rode in my motorcycle training class, which was smooth as silk.  My LS engine just purrs at idle but does have some 'gnashing sounds' at 45 to 50 mph (maybe this is the inadequate chain tensioner mentioned elsewhere in this forum?). It does not sound or feel smooth at speed. Correct  . . . I don't know if this thing had oil squirted into the chamber before sitting for 14 years. At $1900, my investment is modest enough to avoid worrying about it. The second owner changed oil right away and replaced the carb and battery, due to storage concerns. This is what he says, but he didn't produce receipts or the original carb.   The oil level is fine. Cosmetically, it looks like new. No leaks, scratches . . . nothing. I do know that one lungers aren't as smooth as a twin, but this vibration seems excessive.  Maybe I'll take it in and have the tires replaced . . .  this is a good idea.

Tires are not the problem. As long as they are not hard or cracked, they are okay. Just don't see how fast it will fly through a corner or down the highway. Do the thumbnail test.
First thing to apply yourself to is the vibration issue.
After that, if it really is time for tires, read up, get the front tire Located, know what you are spending. Get quotes on installing, tube, rim strip, tire. Shop around, you might be ahead to get a tire shipped to you, haul the front wheel and new stuff into a shop. You park the bike and let Them pull the wheel it gets expensive,, fast.
Rear? It's more,

You got Any mechanical experience at all?

I'm voting tires. Who knows, there could be water in there, an ant bed?  After that much time anything is possible besides the potential for flat spotting and dry rot.