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Remus Powercone exhaust plus K&N air filter equals backfiring

2K views 12 replies 7 participants last post by  Superduper 
#1 ·
Also, since adding the exhaust and filter the bike stalls one time about 20seconds after startup every morning now(unless I blip the throttle a touch). My question is...Between the Dynojet PCFC, Dynojet Power commander 3 or 5, the Procom PowerJet, or BoosterPlug, etc. What's the "easy/economical" go-to for a EFI fuel controller on the 2007 F800S. I've been searching the forums, and I'm hoping someone has my "somewhat common mod" setup on an F800. Currently I'm thinking to go with the BoosterPlug. I just got this bike 3 weeks ago so I'm just getting up to speed on my new machine. Only has 5,500 miles but it is 12yrs old. The sound is nice, and even the moderate backfiring on deceleration is cool. I really like this bike a lot and want it to last a long time so don't really want to run the bike in a too lean state forever. BTW Does anyone know for sure if the Hexcode GS-911 will display the Air Fuel Ratio, live, using the O2 sensor perhaps. That's 2 questions really.
Anyway...thanks in advance for any info that can be offered.
 
#2 ·
Howdy,

If you get a map-driven piggyback controller like a Power Commander you'll need to load it with a map that has been written to work with your modifications. If they are common there might already be maps available, otherwise you'll need to go to a Dyno & have them create a map specifically for you. Self-learning piggybacks will do just that... learn & adjust their inbuilt map as you ride. Whilst not giving as good a result as having a map done by a Dyno... they are still pretty good & unless you are chasing the ultimate performance would be good enough.

I used a BoosterPlug & it certainly worked as-advertised out of the box, but my butt-dyno said it's impact reduced over time. Smarter people than me believe the bikes ECU eventually learns to ignore it. I have been using an AXF-XiED for over 12 months & am really happy with it. Worked out of the box, can easily be adjusted by me to experiment with the effect of different settings & seems to have as much effect now as when I fitted it.

I don't have a GS-911 but I do not believe it'll report real-time A/F ratio. Others with more first-hand knowledge would be of more help.
 
#3 ·
The GS-911 will display O2 readings live as well as data log the info to review later, but don't forget that it's a narrow band sensor, you'll only know if it's richer or leaner than stoic. What it's really useful for is determining if the sensor is working properly or not because if it is, then you're problems won't be solved with a fuel controller, only masked.
My guess is your problem is something else, plenty of people running slip-ons and non-stock air filters on otherwise stock bikes with no issues. I would suggest getting the GS-911 and using it to check for error codes, something as simple as a bad O2 sensor can cause your problem. If all checks out, then us the GS-911 to reset the learned adaptations and that may very well solve it. It may not too, but that's all part of troubleshooting. At the very least you'll have some pretty solid information to move forward with. The data logging alone is worth it to find weird problems that never happen when you want them too.
 
#4 ·
Does it only stall in the morning after a cold start, not after any warm start like during a ride? If so then I would check the Idle Control Valve (item 3) is operating correctly & the vacuum tubes (items 10).

For the low cost and ease, I would replace the vacuum hoses anyway, and worth cleaning the ICV and surrounding area to ensure it's not sticking.
 
#5 ·
A dirty secondary air system valve will also cause popping on decel. It can be cleaned 2 ways. The best, but hardest way is to take it off, clean all the parts, then put it back together. Your supposed to use new gaskets. It's on top of the valve cover. The easy way is to remove the hose from the airbox end and squirt wd-40 in there while holding the engine at 3-4k RPM. It creates a huge smokescreen, but really cleans it out well. Popping gone, or at least significantly reduced. I do mine every few years. I have a Ztechnich slip on and a booster plug. I have noticed that the effects of the booster plug disappear after a few months. So whenever I have the plastic off, I disconnect it and run the engine for a bit with several off and on with key. When I plug it back in it's back to full effect.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 
#6 ·
Well, this is good info. I'm supposed to be Christmas shopping, and now I've all this to think about and do.
I just got the GS-911 and there was only one engine fault code, that seemed to be a fluke as, it was no longer present. I havnt spent enough time to read the O2 sensor lambda info yet. Is getting to the Idle Control Valve under the airbox somewhat quick and easy? (once I remove the 18 fairing screws)[sure] I need to apply sealant to the leaky valve cover gasket too. Unfortunately the AXF-XiED is no longer available. So Ill think on that some more. Nice to know the BoosterPlug can be made to work. Thanks for the informative replys. On the up side, I'm loving this bike. I've been riding/commuting nearly every day for 20+ years and this bike is impressive on a few different levels...I discovered today that the blinkers are self cancelling. Woohoo!
 
#9 ·
You only need to remove the top screws from the side panels, you can keep the lower screws in and the fairing on the bike. It's easy enough to manoeuvre the middles and top side sections out/in once you learn this time saving/faffing technique!
 
#7 ·
The idle control valve is screwed to the bottom of the airbox. Very easy once the air box is off.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 
#13 ·
I do a K&N, seems cheaper to me, I guess I'm a doink for using it letting the microns in, imagine all the microns going into my lungs.
I get muffled pops with the stock can on decal. I also get a stall sometimes on a cold start, maybe even two. Ive just started and twisted the gas to 2K for 10 seconds or whatever.
Just did the tps reset thing? 5 times on and off 5 second thing, I do that once in awhile for whatever it does or doesn't.

I can't remember how to turn out the head lamp? Any one remember the buttons you gotta hold?
 
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