Backfire when blipping throttle for downshifts

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deforj
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Backfire when blipping throttle for downshifts

Post by deforj » Wed Jul 05, 2017 11:59 pm

Hi,

I bought a 2013 990 smt about three weeks ago. The bike has very low mileage, about 16 000k's. I am already in love with it. But I have had an issue with it, on deceleration, when i blip the throttle to pass a lower gear the bike sometimes make a pretty loud backfire instead of revving up. On two occasions the backfire stalled the engine. Today it happened and the engine made a pretty scary noise when it stalled. It also took more time for the starter to restart the bike than usual. It seems to happen only when the bike is very hot, witch does not seem to take much time in the traffic under the sun with this bike.

Did anyone had a similar issue? What could that be? I'm going back to the dealership where i bought it on friday, would love to have some clues from here first so i know what i'm talking about when i get there.

From what i know the bike is stock. It has stock pipes and everything.
Last edited by deforj on Thu Jul 06, 2017 12:07 am, edited 1 time in total.

deforj
125cc
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Joined: Thu Jun 15, 2017 5:33 am
Country: Canada
City: Montreal
Year: 2013
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Model: SMT

Re: Backfire when blipping throttle for downshifts

Post by deforj » Thu Jul 06, 2017 12:00 am

Just one thing to add:
The bike has not had the 15 000K's valve check done yet.

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Winterwolf
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Re: Backfire when blipping throttle for downshifts

Post by Winterwolf » Thu Jul 06, 2017 12:22 am

My guess is someone's disabled SAS in the ecu, but not actually removed the actual system from the bike and fitted the blanking plates.

Look online for a guide, it's easy enough to see if it's had the blanking players fitted

After only 3 weeks the place you bought it from should be helping you I reckon

I used to get mental exhaust pops on the over run or downshifting because of that.. I fitted the SAS removal kit and it went away.

Though never heard anyone having it stall their bike

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jhalfhide
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Re: Backfire when blipping throttle for downshifts

Post by jhalfhide » Thu Jul 06, 2017 6:26 am

I'd definitely say the previous owner has fiddled with TuneECU. Best thing would be to delve into that yourself as you'll come out the other side with one hell of a bike.


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Now: 2013 KTM 990 SMT
Old: 2010 Ducati Faultistrada 1200s (Broke)
Old: 2007 Yamaha R1 (Sold)
Old: 2009 KTM 990 SMR (Stolen)
Old: 2008 Ducati 848 (Written off... whilst parked :roll: )
Old: 2007 ZX6R (Written off... elderly driver)
Old: 1996 ZX6R (Sold)

Trottllebody
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Re: Backfire when blipping throttle for downshifts

Post by Trottllebody » Tue Jul 18, 2017 9:23 am

Hi, i am running map#20, when adding 1% fuel it started popping a bit

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jhalfhide
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Re: Backfire when blipping throttle for downshifts

Post by jhalfhide » Tue Jul 18, 2017 9:43 am

I'm running 20. Started out with 2% and now dropped to standard 20 map. Was too rich with any extra for me (UK).


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Now: 2013 KTM 990 SMT
Old: 2010 Ducati Faultistrada 1200s (Broke)
Old: 2007 Yamaha R1 (Sold)
Old: 2009 KTM 990 SMR (Stolen)
Old: 2008 Ducati 848 (Written off... whilst parked :roll: )
Old: 2007 ZX6R (Written off... elderly driver)
Old: 1996 ZX6R (Sold)

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