Trouble starting the V4S

If it’s cold out a lot cold cranking problems will be with the lithium battery. They need to heat up. If you’re cranking us getting stronger every time you crank it it’s probably the battery. Lithium batteries are notorious for this.

n8V4 said:

What octane number is the bike tuned for from the factory? I don't think most places in the world have 98?

I have been using 98 and it's a pig to start in the mornings. I takes 3 attempts at least with the bike in neutral to get it going. Even then it only just kicks over and takes 20seconds of nearly stalling again to settle at idle.

I'm going to try 95, just interested if there is a noticeable drop in power.

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I think the US quote an octane number that is the average of RON and MON, so is usually a lower number, but equivalent to the higher numbers we have here in Australia.

I personally felt the power with Caltex 95 was more than BP ultimate (but that is anecdotal)

jmhamilton68 said:

If it’s cold out a lot cold cranking problems will be with the lithium battery. They need to heat up. If you’re cranking us getting stronger every time you crank it it’s probably the battery. Lithium batteries are notorious for this.

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In my case, it’s definitely not the battery. I bought the bike in August (which here in Australia was the middle of winter). Prior to the 1000Km service, the bike started first time everytime, quite often in sub-zero Celsius temps.

this only started after the first service (so I don’t know if some kind of re-map is done).

almost immediately after the first service, it started happening, and we’ve had 35-40 Celsius days recently. I also tried charging the battery over night once, and had a problem the next day. Strangely it’s not everyday. It’s every 2 - 3 days. Just got back from holidays, so interested to see if it starts on Monday for work ;-). hasn’t had the problem since using RON 95. Fingers crossed !!

DucatiKev said:

I think all these issues would be solved by having your bike’s ECU flashed with something like BrennTuning which has worked well for me, or some other tuning alternative.

it should be specific to whatever exhaust you have on the bike, yes even stock

Also might want to consider removing the EVAP canister

I remember when the 2020 BMW S1000RRfirst launched and ppl we’re having idle and cold start issues. Not to mention 40+hp loss in the midrange. ECU software tune took care of all of that

2018-2019 Ducati V4 / V4S / Speciale Handheld Diagnostic Tool (Stage 1)

Remove your restrictions with a BT Moto and unlock your Ducati V4 / V4S / Speciale with our handheld flasher.

brentuningmoto.com

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My bike had the Akrapovic slip on mufflers, EVAP canister was removed and the Akrapovic upmap tune. Bike still struggled on cold start while using 98 RON. Changed to 95 RON and never had a cold start issue again. I also didn't notice any power loss with using the lower octane fuel as the bikes are tuned for 95 RON from factory and with the Akra upmap.

PanigaleV4S said:

My bike had the Akrapovic slip on mufflers, EVAP canister was removed and the Akrapovic upmap tune. Bike still struggled on cold start while using 98 RON. Changed to 95 RON and never had a cold start issue again. I also didn't notice any power loss with using the lower octane fuel as the bikes are tuned for 95 RON from factory and with the Akra upmap.

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Yup, So hadn't started the bike for 15 days after going on leave, and she fired up straight away. 3 tanks into RON95, and I haven't had a starting issue. I don't want to jinks it, but I think that's job done. It also starts like how it used to (slight hesitation, then strong run at 2K rpm... as opposed to spit, splutter, backfire, surge etc...).

Thanks for all the responses and advice. I still don't understand why... at 14:1 compression you would have thought the RON98 would work well. Ah well, all's well that ends well.

As far as I understand.....

Octane rating has nothing to do with power.

The higher the octane rating, the more resistant to ignition/combustion

If the bike is tuned to run on 95, using 98 is probably not going to help because the fuel is more difficult to burn but it still has the same energy density as 95.

PanigaleV4S said:

My bike had the Akrapovic slip on mufflers, EVAP canister was removed and the Akrapovic upmap tune. Bike still struggled on cold start while using 98 RON. Changed to 95 RON and never had a cold start issue again. I also didn't notice any power loss with using the lower octane fuel as the bikes are tuned for 95 RON from factory and with the Akra upmap.

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I’m suggesting a full ECU flash vs Akra UpMap. My 1299 starts and idles nicer than b4 my flash and I know the 2020 S1000RR is the same way:





I’m sure there are other flashing methods. This one works great for me. I can even shut off DTC and ride wheelies for days

isnt the BrenTuning still in development for the V4?

It looks like it’s ready to go and I’ve seen some videos and reviews of it working well.
Only item still under devolepment is probably cruise control which we’ll probably never see.. but maybe they’ll surprise us

BrenTuning's flash for the V4 has been available since early Spring 2019.