[Dwilliams]

I purchased a 2012 Scrambler a few months ago and have noticed what feels to me a surging or pulsating feel at constant throttle at most any speed. I am running the 2 into 1 arrow exhaust with the correct map. I don't believe it to be a lean situation as it still does it when I pull out the choke a little bit. I have had it to two different dealers and they haven't noticed anything amiss. My question is could what I feel as surging actually be due to the 270 degree firing order? I am coming off a BMW R1200S and have never experienced any surging or pulsating on it. Any comments from those of you that have rode both the Scrambler and Bonneville would be appreciated.

Thanks!

 

[richm]

pulsating or surging? "Pulsating" could indeed be down to the uneven firing pulse in a 270 motor, but it should not surge. If what you're feeling is the throttle being a little snatchy/uneven at small openings, an adaptive reset could help smooth things out. I would also remove the Air Injection system (or at least block it off) before doing the reset. BTW, the "choke" is not really a choke on an EFI bike, it's more of a fast idle for use when starting.

 

[Dwilliams]

pulsating or surging? "Pulsating" could indeed be down to the uneven firing pulse in a 270 motor, but it should not surge. If what you're feeling is the throttle being a little snatchy/uneven at small openings, an adaptive reset could help smooth things out. I would also remove the Air Injection system (or at least block it off) before doing the reset. BTW, the "choke" is not really a choke on an EFI bike, it's more of a fast idle for use when starting.

I have the AI immobilized (marble trick) and have tried the adaptive reset twice. You may be right about the fast idle, so it still could be a lean situation I suppose. I am considering capping off the O2 sensors, going with a DNA filter, Breathe system and remap offered by Triumph Twin Power (TTP) in England but I wanted to get this situation sorted out first

 

[GDCobra]

Surging at a constant throttle is possibly caused by the EFi system going into closed loop mode, would not expect this at high speed though. The 10 minute adaptation may help as it should allow the system to closer to expected AFR and hence less hunting when in closed loop. Maybe.

 

[Papa Weeley]

I don't know if this is answering your question, but I'm addressing your thread title: my understanding is that the Scrambler has a 270 degree firing order, and the Bonneville a 360, which makes for a very different effect.
I just bought a new Bonnie, so have recently ridden both, and I can tell you that the Scrambler has a much more "lumpy" idle and rev than the Bonnie. Kind of like the lopey sound/feel of a Harley V-twin vs. the smoother Ducati V. Personally, I didn't like it, and it was one of the reasons I went with the Bonnie.
The phasing of many twins' firing order is different by design - even in similar engine layouts - giving a totally different feel, sound and power output.

 

[Dwilliams]

I don't know if this is answering your question, but I'm addressing your thread title: my understanding is that the Scrambler has a 270 degree firing order, and the Bonneville a 360, which makes for a very different effect.
I just bought a new Bonnie, so have recently ridden both, and I can tell you that the Scrambler has a much more "lumpy" idle and rev than the Bonnie. Kind of like the lopey sound/feel of a Harley V-twin vs. the smoother Ducati V. Personally, I didn't like it, and it was one of the reasons I went with the Bonnie.
The phasing of many twins' firing order is different by design - even in similar engine layouts - giving a totally different feel, sound and power output.

Thanks! I would like to hear from people who have had both bikes

 

[warrewp]

I see that your thread has died off a little, but I am having the same or similar issue with my 2012 Scrambler. It rode great the first 2500 miles, but now it has begun to give me a pulsing or surging sensation when riding at a constant speed or attempting to accelerate. At first it was very subtle, but it has gotten worse. It feel like it is going to lose all power at any moment in accelerating. I am not sure what the issue is... I thought something could be caught in the air filter, because this is how my car acted when the MAC got disconnected, but... nothing in the air filter, no check engine lights. Everything on my bike is stock at the moment.

 

[Dwilliams]

I see that your thread has died off a little, but I am having the same or similar issue with my 2012 Scrambler. It rode great the first 2500 miles, but now it has begun to give me a pulsing or surging sensation when riding at a constant speed or attempting to accelerate. At first it was very subtle, but it has gotten worse. It feel like it is going to lose all power at any moment in accelerating. I am not sure what the issue is... I thought something could be caught in the air filter, because this is how my car acted when the MAC got disconnected, but... nothing in the air filter, no check engine lights. Everything on my bike is stock at the moment.

Thanks! I thought it was just me. My bike has a little over 2,000 miles on it. I am considering going to the TTP system which plugs off the O2 sensors, AI and adds the breathe cover,DNA filter and EFI remap hoping this would eliminate that surging. I got to thinking about my new throttle and thought the cam on it might also be a problem but haven't switched back to the stock one to check out that theory. I want to go back to the dealer and ride a Scrambler demo to see if I still feel the surging on a stock bike. Let me know if you find a solution and I will repost when I finally figure out what is going on

 

[casida]

You'll want to check your throttle body balance. I've noticed it swings out of spec in the first few thousand miles pretty regularly. This can be done with an OBD-II cable and TuneECU. TTP site has a good little how-to.

http://www.triumphtwinpower.com/tuneecu-key-functions.php#H

It's very easy. The symptoms of misbalanced throttle bodies are a pulsation, jiggly idle, and unevenly heated exhaust runners (evidenced by uneven bluing or just measuring the runners with an IR thermometer.

 

[richm]

Thanks! I thought it was just me. My bike has a little over 2,000 miles on it. I am considering going to the TTP system which plugs off the O2 sensors, AI and adds the breathe cover,DNA filter and EFI remap hoping this would eliminate that surging. I got to thinking about my new throttle and thought the cam on it might also be a problem but haven't switched back to the stock one to check out that theory. I want to go back to the dealer and ride a Scrambler demo to see if I still feel the surging on a stock bike. Let me know if you find a solution and I will repost when I finally figure out what is going on

HIGHLY recommend a TTP tune, especially with the Breathe, DNA filter and air box baffle removed (and, I assume, a decent flowing exhaust). Once you do, it will feel like a different bike.

 

[warrewp]

Okay, I'll try all of this, this weekend. I took off the snorkel last night and I'm planning a bafflectomy and remap next week.


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[Olhogrider]

Just do it! My 2012 Bonnie ran great but the dealer said the throttle bodies were out of sync. The Scrambler came with the Arrow 2-into-1 pipe. I did the A/I, o2, baffle removed from the airbox, Breathe and DNA. Added the TTP tune. This bike is PERFECT! You will love it!

 

[Armando Gonzales]

I purchased a 2012 Scrambler a few months ago and have noticed what feels to me a surging or pulsating feel at constant throttle at most any speed. I am running the 2 into 1 arrow exhaust with the correct map. I don't believe it to be a lean situation as it still does it when I pull out the choke a little bit. I have had it to two different dealers and they haven't noticed anything amiss. My question is could what I feel as surging actually be due to the 270 degree firing order? I am coming off a BMW R1200S and have never experienced any surging or pulsating on it. Any comments from those of you that have rode both the Scrambler and Bonneville would be appreciated.

Thanks!