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Ok I have searched around bit and posted before, but I am still having problems with sputtering at low rpms (under 4000)

My bike: 02 f4i, APE cam chain tensioner, two brothers V.A.L.E slip on, power commander with two brothers map from powercommander.com, anything else is just cosmetic.

Situation: Bike starts and idles fine. No noticeable low rpm power issues (i.e. acceleration is fine even from stopped position). I get a sputtering/popping sound at lower rpms but especially when I let off the throttle. I sometimes smell gas (unless I am going crazy). I do not see smoke or flames from the exhaust. Battery connections are fine (just connected my PC so I checked the connections at that time)

I am confused for a few reasons I thought sputtering indicates running lean and gas smell indicates running rich? Also the power commander smoothed out the problem a bit. The problem used to happen in the midrange rpm as well (around 5-6k) and the PC got rid of that.

I thought maybe fuel pressure regulator, but don't you get start and idle problems with that issue?

I'm new to self dianosis so bear with me. If you have any ideas of what I should check next or need other info let me know.

One other thing I have the two brothers p1r silencer installed, but I doubt that would cause sputtering. I could be wrong.

Thanks

 

what was the last thing you did before you experienced this?

when was the last time you got the plugs done?

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Mawfaki # 0.5
"Let the ignorance die with the ignorant" - Tahoe SC

WOW....TAHOE........You are still alive........LOL

You could try a different map(s) and see if it goes away......those maps are just a base map anyways.

Jeff

 

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My bike-2002 F4i-With OEM CCT......And no rattle
"Life would be boring if everyone was perfect"

Plugs were changed in march/early april.

The last thing that changed before this problem started was the two brothers exhaust. I had a very very small amount of sputtering sound with the stock can, but nothing that botherd me too much or caused alarm.

I recently checked the exhaust for leaks but could not find anything. Although, I'm not sure how to really do a thorough job of this.

I also adjusted the map a bit but it didnt make a noticable difference.

 

I've got an '01 F4i that I picked up about a month ago. It's basically stock mechanically with the exception of a Jardine exhaust. My bike does the same thing. If I'm going slowly through a residential area for instance, it sputters. It doesn't like just sitting in the low rpm range, under 4,500. The bike seems fine other than that, on the streets under most any condition it's cool. My bike's got around 12k miles on it and I don't know much of anything about it's maintenance history.

My bike hasnt been out much in the past few weeks cause I was moving. I have a fuel pressure regulator and a new air filter waiting to be installed. I'm still hoping it is a fuel/air ratio problem that can be fixed by something simple like the fpr or filter. I'll keep posting any results I have, but it may be slow coming. I just hope if it is the fpr that I havent fouled the plugs by riding while the cylinders are being flooded with gas, but I guess we'll see. The season's almost over up hear in Toronto, so I'll have a winter project.

Check your air filter to make sure it is clean and replace if necessary.  Also is your power commander map made for the slip-on or for the full system?  If it is the later then you will be running too rich.  You can also manually adjust PC without connecting it to a computer.  Play with the buttons to make it leaner then richer and see whether it changes anything.  Let us know how it goes.

I'm just waiting until I have a spare minute to change the filter but I think I'll give the power commander buttons a whirl tonight after work.

Thanks.

Just an update....replaced the FPR and airfilter and checked to make sure there were no loose or kinked hoses. My bike is still not running perfectly yet. I think I may eat the cost and send it to a professional. I don't want to keep ordering parts with no idea what the problem is.