r/Softail • u/DConmusic • 1d ago
Softail vibration help
2017 Softail Slim 103 twincam vibration issue.
I’m sharing this for input and also just to share info that might be helpful to others.
Milage 12k
I bought this bike new from dealership. I have had no issue with the bike. I haven’t put many miles on it because I have other bikes and switch up a bit.
The rear tire needed to be replaced so I pulled it and took it for replace ( local Cyclegear ) I also got some new front and rear brake pads to install while I was working on it. I installed the new pads and rear wheel. I have the tools to check drive belt tension and rear axle alignment. All checks good. I took the bike for a test ride and I immediately noticed vibration under acceleration and at highway speeds. This was not here before the new tire. I immediately pulled the wheel and has cyclegear rebalance the wheel. It was slightly off so I has hopeful but no improvement after the additional balance. The front tire also needed replacement so I did that too. Vibration remained. I checked the following:
Drive belt tension
Rear axle alignment
All torques
All checked out ok. I still had vibration that can be felt in handlebars and floorboards. It may be in my mind but I think it increases after the engine gets up to high temperature.
Next item: I put the bike in neutral and revved the engine. The vibration is there so I started attacking other items. I replaced sparkplugs thinking maybe it was firing perfectly. NO improvement.
I pulled primary cover and thought maybe I would seem an issue there. The nut was not loose and everything looked brand new. I pried a bit on the compensator and there was no movement. I didn’t check the nut torque because I don’t have the correct socket. I did try to move it with a huge pair of channel lock pliers ( I realize I can’t get much torque with those ) but it seems tight. Things “ looked “ ok. No metal shavings in primary oil. No indication that there was an issue.
My next thought was maybe the exhaust was binding for some reason. I removed the slip ons and did a test ride. No improvement, vibration still there. I have also replaced the riser bushings with new OEM rubber bushings. The ones I removed had not hardened. No improvement with that either.
Next plan is to pull primary cover again and check the compensator nut torque and also check the chain tension again. I’m thinking maybe the chain is actually too tight. I didn’t do a thorough check last time. I just couldn’t get my head around a bike with 12k easy miles having an issue like that. But there is certainly something that has change. This vibration just started. It is very annoying especially on the throttle hand. For reference I’ve been riding and working on Harelys since the 90s. I’ve owned ironheads ,shovelheads, evos and build a rigid chopper using a Buell engine. I’ve done lots of maintenance and upgrade work in the past. This is however the first twin cam I’ve been exposed to. I was thinking that I did something when I changed the tires and brake pads but as I said there is significate vibration in neutral also. I plan to pull primary again this weekend. I would like to hear your ideas and recommendations. I may be entirely off base but I’m so confused LOL.