KTM Duke 390 Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
Hi all,

A new bike, a new forum!

D390 2019 with 39 miles on the clock so still running in and a Akrapovic slip on (unfitted).

I have done the usual over searching on the forums and decided I need:-

41t rear sprocket - Any UK distributors that are recommended? - Jerkiness
Coober ECU performance kit - help other mods that will be added
DNA airfilter

Cheers

Adi
 

·
Registered
Joined
·
6 Posts
I forget what the sprocket sizes were on the 390 I used to own so don't know if 41T is going the right way. However, I raised the gearing on mine (ie smaller rear sprocket) which made it much more pleasant - less snatchy in first gear and less frantic on the motorway or open road. No open road loss of performance.
I don't know if the 390 still has a cable-operated throttle but there was a different, more progressive, insert for the twist-grip - it's like a white delrin or nylon snail cam that the cable inner winds over and its form determines the rate of throttle opening. It slowed the initial rate of opening, which seems to be adjusted for traffic light heroes, (like the gearing). It may have come from the R version. I got it from the KTM centre in Hemel Hempstead.
 

·
Registered
Joined
·
4 Posts
Discussion Starter #5
I forget what the sprocket sizes were on the 390 I used to own so don't know if 41T is going the right way. However, I raised the gearing on mine (ie smaller rear sprocket) which made it much more pleasant - less snatchy in first gear and less frantic on the motorway or open road. No open road loss of performance.
I don't know if the 390 still has a cable-operated throttle but there was a different, more progressive, insert for the twist-grip - it's like a white delrin or nylon snail cam that the cable inner winds over and its form determines the rate of throttle opening. It slowed the initial rate of opening, which seems to be adjusted for traffic light heroes, (like the gearing). It may have come from the R version. I got it from the KTM centre in Hemel Hempstead.
Hi Andy,

What year was your 390?
 

·
Registered
Joined
·
6 Posts
Hi chap

welcome. Google B+C Express in Lincoln.
They will make what ever you want, they look like a Renthal sprocket.
Take a look at my profile pic.

cheers.

N. I’m in Matlock.
 

·
Registered
Joined
·
6 Posts
Hi,
Yes I saw those but just didn’t want an orange sprocket with gold chain, I wanted silver with 47 teeth.
 

·
Registered
Joined
·
1,005 Posts
Fair enough, you can get these in black or a couple of other colours and the chain (in this case an RK x-ring) is available in many colours as well.
I only posted the pic to give you an idea of what they look like.
The number of teeth options are plentiful.

Hi,
Yes I saw those but just didn’t want an orange sprocket with gold chain, I wanted silver with 47 teeth.
 

·
Registered
Joined
·
6 Posts
Hi Andy,

What year was your 390?
I think my 390 was 2016. Some people seem to like gearing them down (ie more revs for less speed). I went the other way (lower revs at same speed) and found the bike far smoother and no slower. As I am traditionalist and don't want to wheely away from traffic lights it suited me just fine. I think from memory it was one tooth more on the gearbox but it might have been two or three less at the rear wheel.
 

·
Registered
Joined
·
6 Posts
Hi Andy

what ever is your poison with regards to gearing, the message was just about B+C. Really good quality at a reasonable price, they will do what ever size you want.

Cheers chap.
 

·
Registered
Joined
·
592 Posts
If you just want to cure the jerkiness at low speed then fit a Rapid Bike Easy. It’s a small box that alters the fuelling slightly to cure the issue at low speeds.
It transforms the bike for around £140.

There’s also another device called “booster plug” which is not as sophisticated but does also cure the jerky low RPM issue on this bike.
 
1 - 15 of 15 Posts
Top