Exhaust / Fueling question

[Ojn]

Afternoon All,

I have had my 2017 RR Sport for about 6 weeks.
it had about 1200 miles on it when I got it and it has an Akra shorty GP slip on can.

When it is at idle, it very noticeably hunts.
Also when you are in gear and are holding a steady constant throttle, it feels like it surges.
for example, 65mph in fourth gear, 80mph in sixth.
I?m guessing it is running lean?

i believe the can was fitted by the dealer when the bike was purchased new by the previous owner.

I have heard from different sources that with a slip on, there should be no issues, with fueling, but also that, the bike will hunt at idle as a result of the slip on.

I had the TPS reset, but this has made no difference.

I guess my question is, has anybody experienced the above and is there a solution to both issues?

Thanks for your help.
Oli.

 

[Eddievtwin]

Following

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[Chocolatier]

If you think its the can, and you still have the cat fitted, just take the can off and ride to see if its the can causing the issues, it'll be no noiser but watch where you put your foot as the hot gases exit near you.

My 17 plate hunted the same when new and before I changed the can or pipe, get it above 4k and its smooth as silk, its a racer not a shopper

 

[pof]

Get a dyno run. It should only be about ?40 . From there you can see what if anything needs to be done ie pc5/bazzazz or flash

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[alex]

Afternoon,

I have had the surging...this is very interesting as no one else seems to have before. I first had it when the RapidBike was fitted so put it down to the map, tinkered a bit and also thought that it might be the TPS.
I deleted the RapidBike using the terminator I bought with it and on the road it improved but didn't clear completely. It's worst at smaller throttle/rev points - i.e. 30mph in 4th.

Now I have a new throttle fitted but as the bike is off the road I can't test it to confirm if that has changed the behaviour.

My engine mods, RapidBike Race (O2 Sensors still connected), Sprint Filter, Akra full SYSTEM.

FWIW it's totally not normal even with an exhaust on. The lumpy idle is 100% normal. Its the shunting at speed that is very different. Does it feel like it's slightly "stuck" too, mine seemed to be in this closed loop bucket it couldn't get out of.

Afternoon All,

I have had my 2017 RR Sport for about 6 weeks.
it had about 1200 miles on it when I got it and it has an Akra shorty GP slip on can.

When it is at idle, it very noticeably hunts.
Also when you are in gear and are holding a steady constant throttle, it feels like it surges.
for example, 65mph in fourth gear, 80mph in sixth.
I’m guessing it is running lean?

i believe the can was fitted by the dealer when the bike was purchased new by the previous owner.

I have heard from different sources that with a slip on, there should be no issues, with fueling, but also that, the bike will hunt at idle as a result of the slip on.

I had the TPS reset, but this has made no difference.

I guess my question is, has anybody experienced the above and is there a solution to both issues?

Thanks for your help.
Oli.

 

[pof]

Afternoon,

I have had the surging...this is very interesting as no one else seems to have before. I first had it when the RapidBike was fitted so put it down to the map, tinkered a bit and also thought that it might be the TPS.
I deleted the RapidBike using the terminator I bought with it and on the road it improved but didn't clear completely. It's worst at smaller throttle/rev points - i.e. 30mph in 4th.

Now I have a new throttle fitted but as the bike is off the road I can't test it to confirm if that has changed the behaviour.

My engine mods, RapidBike Race (O2 Sensors still connected), Sprint Filter, Akra full SYSTEM.

FWIW it's totally not normal even with an exhaust on. The lumpy idle is 100% normal. Its the shunting at speed that is very different. Does it feel like it's slightly "stuck" too, mine seemed to be in this closed loop bucket it couldn't get out of.

Alex does it do it in all modes?

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[Ojn]

Thanks Alex,

The surging at speed is like your at a constant speed and then you very quickly hit the gas for half a second, but in reality, you haven’t actually changed your speed. I’m not sure about being stuck in a loop though.
For my own knowledge, why the lumpy idle? I’ve had several Blades in the past with slip ons and not had an issue.

Ive had different answers from different people, some say a PC5 will sort it, some say it shouldn’t happen, BMW say a slip on should not effect the fueling, someone else has said you can’t ECU flash the 2017 RR, so not really sure what to do!!

 

[Ojn]

Thanks pof and Chocolatier,

I guess a Dyno would be useful to see what is actually happening.
Just out of interest, do you either of you have a slip on or a full system?
Do you have the lumpy idle?

 

[alex]

Thanks Alex,

The surging at speed is like your at a constant speed and then you very quickly hit the gas for half a second, but in reality, you haven’t actually changed your speed. I’m not sure about being stuck in a loop though.
For my own knowledge, why the lumpy idle? I’ve had several Blades in the past with slip ons and not had an issue.

Ive had different answers from different people, some say a PC5 will sort it, some say it shouldn’t happen, BMW say a slip on should not effect the fueling, someone else has said you can’t ECU flash the 2017 RR, so not really sure what to do!!

Your 'blades didn't have a 200hp engine with aggressive cams.
Listen to me only. Ignore them others (Yep trust someone you've never met )

So, if it's what I've experienced then it's not going to be changed by a PCV as the rapid bike made it worse (because of the extra fuel it pumped in at lower rpm's for performance).
When accelerating and decelerating it is not evident and it works a charm on track.
It's when holding speed for a few seconds or more. Anything under 7000rpm in my experience.

You can flash a 2017. RS2E/Alpha, BMW etc can. But I'd avoid some others...if you go through BMW it would invalidate the warranty.
There's no guarantee it's fixing it.

 

[alex]

Alex does it do it in all modes?

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Yes.

 

[alex]

Oli, can you feel it on cruise?

- Alex

 

[Ojn]

I?m happy to trust someone who knows what they are talking about and knows far more than I do!!
its still in warranty till March 19(2year warranty?) so could always take it back to BMW.
i had it serviced at BMW in Cheltenham and they seemed pretty good.

 

[alex]

I would, I always thought it was the mapping...but maybe something else is going on.

Like I say I have changed the trottle but I have not had an opportunity to test it.

- Alex

 

[Ojn]

Not had cruise control before. The only thing I notice is say you have cruise set at 70mph and you accelerate, it then lurches slightly when it goes back to the set cruise speed of 70mph.
I think this is probably normal though.

 

[alex]

Try cruise at 40-50 see if you notice it at all. Mine was 90% better on cruise but still just slightly there

- Alex

 

[Ojn]

Thanks very much, will do.
i guess coming from Blades with no electronics at all, to a bike packed full of them, there is the potential for there to be more issues!
Fantastic bike though, regardless of these little niggles.

 

[alex]

Let us know what they say, also make sure they know its not exhaust related.

- Alex

 

[Ojn]

Will do, cheers Alex.

 

[Ojn]

Hi Alex,
I was booked in with Mottorrad Cheltenham today at 10am.
They road the bike, agreed there was definitely an issue, thought it might be related to the Akro slip on.
Changed it for the OEM exhaust and rode it again, same problem.
After much investigation, they looked at the software and decided to upload the most recent version, as the bike didn’t have this.
Hey presto....problem solved.
Has also resolved the majority of the hunting on idle, bike also feels a lot smoother.
Fingers crossed, that’s the end of it!

 

[alex]

Nice one oli.

Thanks for coming back and closing the loop on that. Maybe I can get mine the latest firmware too...

Saying that, it maybe Park Lane did that when coding the throttle.

Need to get a test done in a carpark

- Alex