Should I have bought the RC390 instead? Probably. Do I regret it? Not yet.
I bought my 390 new from the dealership a little under 2 months ago, and I put roughly 6,000 miles on it so far. It has been an excellent commuter and track bike, and it has proven to be quite capable.
Only issues I’ve had so far is the shifter peg snapping off randomly, and shield under the catalytic converter coming loose due to the rivets wearing out; all covered under warranty.
As someone who started by riding dirt bikes, and my first street-legal bike being a dual sport; I wanted something I could take to the track and commute with when I F up my dual sports so bad they’re out of service. Clip ons always felt weird to me, and I feel way more comfortable on a bike with nice leverage-y handlebars.
At The Ridge Motorsports Park in Washington state, my 390 will hit speeds up to 101 MPH on the straightaway and provide full confidence until touching pegs. Although, it could benefit from slightly more race orientated tires (such as the Michelin power cup evo) which provide better tip in and more contact patch at lean. The Power 6’s from factory have provided no issue, although with them starting to square off they aren’t feeling as confident inspiring as they did on previous track days.
Brakes do start to fade after a few laps, I imagine a higher-temp brake fluid and better pads would improve this issue majorly; but I have not noticed a major decrease in braking distance even under the highest demands. ABS can feel pretty intrusive, but it’s mostly trying to prevent the bike from doing a pretty gnarly stoppie.
Power is typical 400cc power, but the mid-range torque helps get you out of tough corners that you’re in the wrong gear for. GP shift could definitely help keep you in the power band in certain situations at the track, but I haven’t felt super constricted with the normal shift pattern quite yet. Only a couple scenarios have I wished to switch it over to GP shift.
Suspension is pretty good, it could use the higher spec Apex Pro drop ins for the most demanding track use; as I do need to raise compression in the rear shock; which is unfortunately not gonna happen with the stock shock. WP offers a replacement for around 1,000 bucks. And drop in cartridges for the front go for around 899, which allow greater fine-tuning, and feel. I have not put any modifications onto the bike yet.
It will scrape pegs, but some cheap rear sets will fix this easily. Necessary, but not life or death for your first few track days. For reference, I’m in B+ group and riding with 600’s and 1000’s mostly, and in the corners keeping up is no issue. Obviously, the minute they can point their bikes in the right direction they can gun it and they’re gone.
The chicane at The Ridge really levels out the playing fields between small and big bikes, it helped me keep behind many of the 600s and allowed me to pass a couple as well.
RC390 will always be the superior track bike, but if you value comfortability for long days and you prefer the egos and feel of naked bikes, I think the Duke 390 is one of the better choices for a 400cc naked track bike.
Does anyone have any suggestions for modifications that could help?
