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Author Topic: Anyone recognize this mod - possible fuel controller (?)  (Read 752 times)

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Offline Pete_in_AK

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Anyone recognize this mod - possible fuel controller (?)
« on: June 09, 2020, 08:51:44 pm »
This is connected to my Bolt's O2 sensor.  I'm thinking that it is a fuel controller but I honestly have no idea.  Just curious if anyone's seen this before.  There are no logos / labels of any kind on it, just an LED that flashes quickly once the ignition is turned on; once I start up the Bolt the light turns steady.

My hope is to pull it out and replace it with a stock O2 sensor, since my Bolt is having this weird issue where sometimes when it's been running for a while it will idle really rough, and eventually die if I don't twitch the throttle every 5 or 10 seconds.  At WOT or when cold it runs perfect.  All of that screams fuel issues to me.  So I was going to bring it back to stock except for the Twin Bros air filter that's on there, pull the ECU and send it to Ivan.  Hopefully that all makes sense.


2015 Bolt C Spec

Offline Sdaniels

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #1 on: June 10, 2020, 01:37:01 pm »
Do you know how many connections there are to this thing?  Cobra makes a fuel controller that has a small black box but it has 6 connectors. 
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Offline lunkhead

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #2 on: June 10, 2020, 02:09:35 pm »
That's looks like a Dynojet O2 eliminator. Here's one made specifically for the R6 that was discarded in favor of a flash. I don't know of any made for the Bolt. If it still has the label, you can look it up and see what bike it was made for. Get rid of it if it's running too rich as you've indicated.

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Offline Pete_in_AK

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #3 on: June 10, 2020, 06:42:15 pm »
Do you know how many connections there are to this thing?  Cobra makes a fuel controller that has a small black box but it has 6 connectors.

There are three connections in total.  One connects to the O2 sensor, one goes to the brains of the bike (I'm guessing here since it is the same connector as what goes to the O2 sensor), and one looks to be power.  Sorry I'm really new to motorcycles.

That's looks like a Dynojet O2 eliminator. Here's one made specifically for the R6 that was discarded in favor of a flash. I don't know of any made for the Bolt. If it still has the label, you can look it up and see what bike it was made for. Get rid of it if it's running too rich as you've indicated.

Unfortunately it has no label at all.  It's just clipped in and attached to the frame with some heavy-duty velcro.  My plan tonight after the kids go to bed is to spend some time in the garage seeing if I can bypass it and then run it for a while to see if there is any improvement.

Do you think there's anything to my idea that the problem happens after I've been riding for an hour or so, when the engine is hotter?  Or is that just coincidence.  Today when I came into work it ran perfect (15 min ride).  Last night I rode it for 45 minutes, not a single issue.
2015 Bolt C Spec

Offline lunkhead

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #4 on: June 10, 2020, 09:12:46 pm »
A really rich condition could look like crap on a dyno but on the road, it could feel pretty good because the effects are less drastic than a lean condition. Throttle response might even improve on some bikes. The only way you might know for sure is by the bad fuel economy. The Bolt averages 50+ mpg but it's not impossible to get as low as 35 mpg riding around town or as high as 70 mpg putting down the highway.

There's no reason for anything to replace the O2 sensor. The Bolt doesn't suffer lean issues other than the fuel cut which has nothing to do with the O2 sensor. Any add-on device is another potential source for problems. Not that the O2 sensor is any better as it does "wear" out. IIRC, Ivan originally made a device that removed the fuel cut and other restrictions before the flash was available.
« Last Edit: June 10, 2020, 09:14:39 pm by lunkhead »
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Offline Sdaniels

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #5 on: June 11, 2020, 06:48:36 am »
When I bought a used Vmax, it had a power commander V & autotune on it...under acceleration it was flawless but steady cruising was horrible.  Had a constant sputtering.  All of it fixed by removing the pcv/autotune.  These things go bad time to time. 
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Offline lunkhead

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #6 on: June 11, 2020, 11:37:37 am »
Some day, I'd like to get a late model W800. It basically comes with autotune but not as an afterthought which means less complexity and more reliabilty. It's hard to find detailed info on it online but I expect a lot of sensors that are typically used for bikes have been eliminated. I haven't looked in the service manual and parts catolog descriptions are vague.

https://m.youtube.com/watch?v=RSE73I4LXe4
« Last Edit: June 11, 2020, 12:19:18 pm by lunkhead »
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Offline Pete_in_AK

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #7 on: June 11, 2020, 05:13:07 pm »
OK boys I just got that thing removed.  Started up the bike and let it idle to make sure it ran ok and didn't throw any error messages.  I'm going on a test drive here in an hour or so and I'll let you know how it goes.  It almost died on my last night on my way home from work so I'm really stoked to have this problem cleared up.  Other than this issue I absolutely love this bike.
2015 Bolt C Spec

Offline lunkhead

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #8 on: June 11, 2020, 06:55:36 pm »
Those things are usually used with a PCV. Have you looked under the seat for one?
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Offline Pete_in_AK

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #9 on: June 11, 2020, 08:47:13 pm »
Those things are usually used with a PCV. Have you looked under the seat for one?
Thanks lunkhead!!  I just checked under the seat and look at what I found.  So now I'm really curious...I'm going to go to their website and see if I can figure out how to program that thing for what it on my bike now - a Two Bros High-Flow intake and the stock exhaust.

I see one on their site that is titled "Stock exhaust, Stock or aftermarket air filter".  I might give that a try?

Also, I'm guessing that I need to re-attach that black box that I pulled out earlier today, the O2 eliminator.  Or maybe not since I have a stock exhaust and O2 sensor in place.
2015 Bolt C Spec

Offline lunkhead

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #10 on: June 12, 2020, 12:08:12 am »
You might wanna put that O2 Optmizer back in so the sensor doesn't conflict with the FC.

You should also look on the bottom of the ECU for Ivan's sticker. The PCV and flash was the recommended combo before Ivan released the 2nd version but the O2 sensor wasn't used.
« Last Edit: June 12, 2020, 12:11:41 am by lunkhead »
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Offline Pete_in_AK

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #11 on: June 12, 2020, 01:18:15 pm »
You might wanna put that O2 Optmizer back in so the sensor doesn't conflict with the FC.

You should also look on the bottom of the ECU for Ivan's sticker. The PCV and flash was the recommended combo before Ivan released the 2nd version but the O2 sensor wasn't used.

Got it, thanks for all the advice.  I really appreciate it.  I feel like I'm getting a crash course in this stuff.
2015 Bolt C Spec

Offline Pete_in_AK

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #12 on: June 16, 2020, 03:34:56 pm »
Just wanted to give an update on this one in case someone else comes along in the future with the same problem.  I got through to Dynojet and talked with them (great cust service btw) and this is what I found:

1. The 'little black box' is indeed a O2 optimizer.  They were made by Dynojet but they don't make them anymore.  This one is not even for this model of bike.   ;D  He recommended that I take it out of the loop entirely and that it is almost certainly what is causing the problem.

2. I confirmed with him the map that I'm using is the right one for my setup.  Hooking the PCV up to my laptop and sending a new map is pretty easy now that I've learned how to do it, so I'm just going to leave it in place. 

Thanks again guys for all your help / suggestions on this.  It's actually kind of cool learning about my bike and all these different mods that people put on them.  Hopefully pulling out the O2 optimizer does the trick.
2015 Bolt C Spec

Offline lunkhead

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Re: Anyone recognize this mod - possible fuel controller (?)
« Reply #13 on: June 17, 2020, 10:49:56 am »
The one I have for the R6 is also NLA. You won't notice much difference between stock and a FC as much as would with a flash unless you're looking at a dyno chart (at full throttle). Some bikes that are super lean throughout the rev range will improve with just a resistor added to right place (Boosterplug) but the Bolt's major malfuctions are due to the factory restrictions at places in the rev range that can't be controlled by a FC.
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