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2018 KTM 790 Duke
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Discussion Starter #1
i know this has been covered... but a lot of the posts are a couple yrs old. any updates
what is the best most cost effective way to smooth out the throttle at slow speeds.
the bike has a slip on ixil mk2 with out baffle.

akro map?
boosterplug?
PCV?

im not chasing more power. just want to smooth out the bottom. if i gain more power in the process so be it. i also dont want to spend a fortune. im more inclined to upgrade brakes and suspension before power.

any shared personal experience will be appreciated..

Cheers
 

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I think I know what you are talking about. 2nd gear? in hairpins? Last time I rode my bike I thought that it would actually ride better with a taller gear ratio, to make 2nd gear less buzzy, but that would most likely render 6th useless.
I find 1st is very low already, like enduro bike low, but I guess you could go lower, therefore making 3rd gear your hairpin corner gear.
More power, tune and more corner speed might solve all your problems too. Im gonna be putting off a gearing change until I get a tune.

(edit) I honestly think Coober is the best option for tuning as it retains the o2 sensors and knock protection. PC5 will give you an engine light. Booster plug I wouldnt bother.

(Akro map I know nothing about but my KTM dealer quoted me $1700 for the Akro slip on and said nothing about a different map being included for the eye watering price)
 

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Not to open this can of worms, yet again, but we have some very strong recommendations in the forum for PCV in street mode and O2 sensors connected. Most reviews indicate a much smoother power band, with the street mapping. Evans just posted a great thread AND a very detailed article.

Saving you the search: Review of Power Commander V and Rottweiler street map with Power Plate
 

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2018 KTM 790 Duke
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Discussion Starter #4
QCS. Sounds good and affordable. The coober and atom were a bit pricey for my liking
 

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QCS. Sounds good and affordable. The coober and atom were a bit pricey for my liking
I didn't see anything in the article about it curing low speed roughness though. In fact the article states the PCV only kicks in around 4500 rpm.

What do you mean by "low speed" ? 15-20 mph?
 

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I have the same issue with low-speed, around-town smoothness at steady-state fueling under 50kph. I did fit a Boosterplug which helped, but by no means eliminated the problem.

What I am discovering is that fueling is DRAMATICALLY improved in Rain mode around town, and I don't miss the peak power while I'm fooling around in the city. What I don't understand is why Street mode can't be that smooth at low revs with almost no power requested. They should be able to eliminate bucking and surging in all power modes, you'd think.
 

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In the US - the PCV has an important price advantage over COOBER. Here not so much. Add import duties and VAT and the PCV is way more 'spensive over here.

What I do not believe is that the PCV recently tested by @EvansB2 makes ignition changes - this is quite an important part of what the COOBER does. If not the Ignition box from Power Commander is more expensive than the fuel box. Here that would make the PCV F+I way more expensive.

Where both score is the improved granularity of measurement and change. I don't know what the KTM stock granularity is - but I am guessing 500RPM-ish cells. Maybe more though from observation of how the tacho reacts with and without the COOBER, my gut says close to 500. .

The PCV I have on my Triumph has 250 rpm cells (there is the option of 500 or 250 on my PCV) - COOBER reportedly is 100rpm. At low throttle openings this makes a big difference to smoothness. Over 10% it all becomes a bit moot. Over 30% - not really much effect honestly. But under 5% it is really key. To give you an idea - feathering through traffic in Madrid - The Triumph (Rocket III) is at 2-5% TPS generally

You can make VERY fine adjustments with the PCV if you have time and a Dyno. And set very custom TPS values. The PCV can also map differently in each gear if you add wires.

The COOBER does take a "leap" of faith. I decided to do it as I spent 100's of hours tweaking the Triumph and really had had enough.
 

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2018 KTM 790 Duke
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Discussion Starter #12
I find riding from 0-50kms frustrating, that's in a straight line. Not to mention tight corners on bumpy roads in town. At these speeds no matter which gear I'm in it feels like the wrong gear.

Coming from Daytona 675. On which I could pick 2nd or 3rd and could commute thru town without changing gears.

The other issue I have is my ktm stalls every time I start it. I usually start my bike then put gloves on. I'll get one on it turns off. I'll restart it and for the first 20 seconds it revs between 1-3k. Before it settles.
 

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Just thought I'd chime in with another view...

Maybe I'm missing something here, but I haven't felt I've had any problems like this surging at low RPM particularly after the first service at 600 miles. The fueling definitely improved for me after that - most noticeably in the 30mph (50 kph) zones through the villages we have here in the UK or in town.

Before the first service, to keep a steady (quiet) 30mph through the villages did feel awkward - 4th gear was too high, 3rd gear felt like it wanted to be given gas and speed up.

After the service this all went away. In 4th gear at 30 mph the bike will happily bimble along nicely on almost zero throttle or in 3rd with a few more revs. It will pull just fine in any gear with no surging as I get up to speed out into the 60 mph zones.

I am pretty convinced that the engine map was changed in some way at this first service.

The quick shifter was also loads better too after this service - the technician told me he spent a while adjusting it, riding it, adjusting it some more - it's awesome now.
 

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I really dislike the jerkiness of mine at low speeds around town. Turning on residential streets is annoying at best. Unfortunate, it totally detracts From the rest of the bike.

picking up the throttle mid-corner and having it jerk all over is uncomfortable.

1)the dead spot in the throttle where the first few degrees of rotation.... don’t feel any different, but are not affecting the engine.
2) the hunting at low rpm

Faster corners are not an issue, it’s the 90 degree or tighter residential corners.

Or worse are the very slow 20mph exit ramps

never rode a bike that behaved like this; it’s a shame.

Anyone try flashing their ECU?
 

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Rottweiler tuned PCV, Rottweiler Performance Power plate, de-cat, stock pipe cleaned up running top to bottom, now when I hit the start button it fires like right now never had a bike that fired so quickly. Also have lithium battery.
 

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In the article. Not in the thread.

"When riding the 790 with the Rottweiler map and Power Plate in place (even while troubleshooting the Power Commander issue), I was impressed by how the midrange felt tighter and more responsive..."

"So now, as I roll on the throttle exiting the corners of my favorite winding road, my smile is even bigger. Fueling is hiccup-free..."
 
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