Just got a low mileage (500) 05 Road King Custom . I'm noticing a noise in fourth gear when accelerating. Is this common for this trans? Almost sounds like a bad bearing.

 

Check the tranny fluid. Change to a good synthetic gear oil like Red Line, Bel Ray, Amsoil, Spectro etc. You'll be glad you did. Syn 3 is for Engines, and Formula plus is not as good as the old Semi Synth tranny oil Harley sold as far as smooth shifting and noise go. Hard to believe a bearing went bad in 500 miles unless it was run dry.

 

They whine in 4th. I've heard its the way the gear is cut.

 

Yeah,my 05 electraglide whines in 4th also since day one.Switched to amsoil severe gear 75w90 in trans.slightly quieter now but still noticeable.

 

I changed the fluid out to Mobil 1 75-140. Didn't make much difference. The only time it's noticeable is when I'm throttling up.

 

Same as my RKC. Amsoil will help, but not cure.

 

Probably same trans as in my 05 Ultra - never heard any trans noise - I use Moble 1 75W90 full syn oil in the trans - change every 10,000 miles. Have like 35K miles on her.

 

Normal. Cut of the gear. I consider it my 4th gear audible warning indicator.

 

I'll go with normal if it is a whine. My 01 does it and my buddies 03 does it. Consider it your new scoots way of telling you have another gear available. Enjoy the new ride.