Six simple modifications for the KTM 390 Duke

The Ktm 390 Duke is an excitingly fast motorcycle as it stands but there is scope for more. The logical upgrade is to install a reflashed or piggyback ECU. However past experience with these on my R15 left the engine feeling rough, even after I returned to the stock ECU. So I set about looking for simple but efficient ways to sharpen my Duke and extract a bit more performance without affecting the warranty. None of these add power or increase the top speed but each one has undoubtedly helped me go faster, be it on the track or the street.

Small mods combine to turn the 390 Duke into a sharper tool

1. Quick throttle

A reduced throttle action makes the bike feel alert and more reactive. It's easier on the wrist too

The 390 Duke is designed for entry level riders overseas and has a throttle to match. I found the the turning action on the 390's throttle was too long, something KTM addressed with the 2015 model. Since mine was a 2014 bike I looked for options and found one made by a gentleman named Dhaval Mahidharia. An engineer by trade, Dhaval has built quite a few nifty solutions for the KTMs like a side stand by-pass switch and more. Dhaval's quick throttle reduces travel by about 20 per cent and is an easy fit. It doesn't affect the rideability in stop and go traffic but makes simply makes the bike feel more urgent and reactive. I've enjoyed using it for a year now without hiccup. Drop Dhaval a message on Facebook to purchase a set 

Price: Rs: 1,000

2. Stomp Grips

Stomp Grips help you hold the bike with your thighs better, which improves control

Stomp Grips are a simple rubberised pad with small bumps that stick to the side of your tank. They are designed to help you grip the bike better with your thighs, reducing strain on the arms which helps you ride better. I found these hugely helpful at the track but also in everyday traffic. The bumps, or volcano dots as Stomp Grip calls them are soft and designed to wear down with time but I have noticed that your pants will wear out at a slightly faster rate at the points of contact.

You get them in pre-cut shapes for the RC 390 at performanceracing.in but I had to buy a square sheet and cut them to size for the Duke. They're expensive but very worth it in my mind. Every motorcycle I own henceforth will be stomp-gripped the moment they get out of the showroom. I've found a cheaper Rs 860 (in America) option  but I have no idea how well this would work.  

Price: Rs 4,000

3. Heel plates

Yamaha v1 heel plates bolted onto the stock heel plate improve the rider's grip on the bike

The Duke has  tiny heel plates that you can't really hold onto with your boots. The reasoning behind this mod is the same as using the Stomp Grips - better grip on the bike with the lower body. Shumi's solution was to pick up a pair of of the R15's heel plates from a Yamaha showroom and bolt them on. Unfortunately, they weren't in stock when I needed them so I had to settle for a set from the FZ v1. The FZ's are cheaper but are slightly curved outwards, making the heel stick out a bit. It's not a problem but I'd have preferred the R15's. You can pick these up from any Yamaha authorised service centre.

Price: FZ heel plates: Around Rs 380
           R15 heel plates: Around Rs 750

4. EBC FA 606HH

These pads generate a sharper bite but only hard riders will appreciate the improvement

The stock KTM brakes are perfectly upto the job but I found myself looking for more. The easiest solution was a brake pad upgrade. EBS makes a sintered brake pad that adds some more bite and lever feel. I could lean on the brakes harder at the racetrack with these pads on and also felt the lever feel was a little nicer. EBC makes a set for the rear brake as well but I didn't bother as I hardly use it.

Unfortunately some accumulated muck in the front calliper jammed one of the pistons which ruined the pads on a recent long ride. I reverted to stock pads after using the EBCs for about 7,000km. Judging by the wear, the EBCs should last about 10,000km which is similar to the stock pads. Are they worth the Rs 3,000 asking price? I'd say only if you're a very hard rider looking for the extra edge. The stock pads get the job done well enough. Purchased at X-torque, Pune

Price: Rs 3,000

5. Philips Xtreme H4 Vision

The more you can see the faster you can safely go

You can go as fast as you can see. More light at night means more confidence to go faster without compromising safety. The stock KTM bulb is quite good but I found that the Philips Xtreme vision which has the same 60/55W rating has a stronger and wider throw of light. It's not a difference of night and day but worth the price, even if it's three times the cost of a standard bulb. Available at amazon.in

Price: Rs 785 

6. Resonate ChargePlus and Rynox phone mount

An efficient, reliable USB source of power designed for motorcycles

This one is a bit of a cheat, but the reasoning is sound. I have a rather terrible sense of direction and get lost pretty easily. Nothing loses you time on a long ride like constantly having to slow down and ask for directions. A simple phone mount partially solves the problem. I use the Rynox phone mount but have my eye on one of those excellent RAM mounts. The issue is that running navigation is a major draw on battery life and a dead phone is never a good thing on the road. Here's where the ChargePlus comes in (LINK). It's expensive but well built, reliable and works well no matter the conditions. Both devices are available at amazon.in

Price: ChargePlus -Rs 2,799
           Rynox 5.5-inch phone mount: Rs 850 

What's next?

I'm pretty much happy with the way the bike is right now but there is one more thing I want to play with - sprocketing. The Duke 390 hits just over 170kmph on the clocks but anything over 150 is slow progress. I'd rather have harder acceleration with a lower top speed. After all, how often do you cross 150kmph?

A bigger rear sprocket will mean harder acceleration at the cost of top speed

I plan on going a tooth up to the 46 tooth rear sprocket. It may not generate a big difference but it will fit with the stock chain. If that's not enough, perhaps a 47 tooth rear sprocket with a longer chain to match, but I suspect it will compromise highway cruise-ability, something I'm not keen on.