Sorry for a long message, but I want to cover the bases. I have around 2300 miles on my 2018 DL650, running factory tires with proper pressure. I've spent time chasing what feels like an out of balance wheel. I have rebalanced both wheels twice between last fall and this season.
35-45mph speeds give an increasing frequency shudder through the bike, feeling like mainly from the front, I think. Highway speeds make it feel like extra buzz vibrations.
The steering seems okay- no issues with the bearings at the head tube. The tires, visually, look okay.
Each time balancing using the Aerostich balancer, I check the wheel before stripping weights- not perfect but as good as you can get with today's steel stick-on weights. (At least the old lead weights could be cut to custom weights.) I'd then strip the weights and start all over again, working hard to tweak the balance as well as possible. So, this was essentially a static balancing process. I don't know of any local shops that have dynamic balancing capabilities. Maybe a local Harley shop- not too many big 4 Japanese shops left anymore, most are little shops struggling to stay afloat.
Barring static balance issues, what are all the other causes of this speed related shuddering/vibration I'm getting? Bad belt in a tire casing? (Wouldn't show in a static balance.) Throttle body balancing? Steering head bearings? Chain issues? It is lubed and tensioned. The wheels are torqued upon mounting to the bike. Accessories are all properly mounted and remain tight- Givi windshield, SWM crash bars, HB C-Bow hard case side cases. (I'm just throwing stuff out there now...) My first thought is a bad tire belt, but replacing tires would be an expensive diagnostic tool, unless it proved correct.
There is a big recent balancing thread in the +17 DL650 subforum now https://www.stromtrooper.com/dl650a-...balancing.html
but I thought this was a unique issue worthy of a fresh thread.