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Discussion Starter #1
I understand that unplugging the o2 sensors changes it to 13.5:1. My question is does it do that through the whole range, or only closed loop area. I hate the lack of info available for the Vic fuel injection. Do they have ve table like the hd? I wish there was a tuner like the power vision available for the Vic's.
 

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This is the first I have heard of an actual number that unplugging the sensors puts it in. I also doubt it is consistent since the bikes are so differ in the way they act.
If you want a HD you should have one, be happy. If you want actual numbers, find a dyno tune, or get a controller to put the A/F ratio where you want it. Plenty of things out there. Unlike some other MC companies, Vic doesn't sell you a bike with the intention of "upgrading" it. It is very rideable and has the gumption to go without telling you that you "need" to upgrade before you start it for the first time.

You'll have to pay for it anyway, so figure out the controller you want and go for it, or leave it alone and see how it does.

Cheers
 

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No where in my post does it say I want an HD. I traded it in on my XC. What I want is to be able to tweak my af ratio after the pipes and air filter were added. So I can get rid of the pesky lean surge at cruise. I like closed loop efi for elevation and temp swings. Just wish I could run 14.2:1 instead of 14.7:1. So it wouldn't surge. I did want a little more sound from the pipes, just because I like it, so I put pipes on. If I wanted a bike to just ride and not mess with I would have bought a Honda F6B.
 

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This is the first I have heard of an actual number that unplugging the sensors puts it in. I also doubt it is consistent since the bikes are so differ in the way they act.
It's also running open loop, hence the amount of fuel being delivered at a given rpm/throttle position will be fixed. Anything that might alter the amount of air delivered (altitude, dirty filter, hot day etc) will cause that a/f to fluctuate.

To the OP, yes, all these systems work the same. They have crappy on/off narrowband O2 sensors that will keep the a/f running approximately stoich at idle and steady throttle. During acceleration, it reverts to the same open loop fuel map it would use if you unplugged them.

So the benefits are that the engine will likely run a little cooler without them. May even respond a little better to sudden throttle applications. The downside is you'll probably lose some fuel economy.

I find that with my O2 sensors unplugged, I generally get 37-38 mpg. With them plugged in around 41-42 mpg. But I did do a long highway trip last year with them unplugged and got some ridiculously good mileage like 45 mpg or so as I recall. The stars must have been aligned for that ride...or I had one hell of a tail wind.
 

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Read one of the pros somewhere say it gives you slightly richer AFR in acceleration and WOT but still rather stock levels lean in cruising.

That said, I'm disconnecting them so I can ride gingerly with the tri ovals installed, all else stock, to Helen for a bit of business on Kyle's bench where such issues become moot after cams, timing wheel, filter, PCV and dyno tune. Hoowah!



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What THE pro says

Here is a link to a thread where I copied and pasted email communication from the best in the business. Lloyd. This was regarding pinging and the causes of it which he thought could be from running too lean. As you'll see by reading the email communication, basically, you can't count on unplugging the O2s to do anything specific for you. It MIGHT go one way or it MIGHT go another way. There certainly isn't a set number that any bike will run at with them unplugged. Your best bet is to get a fuel tuner!

http://www.victoryforums.com/showthread.php?p=822697#post822697
 

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I understand that unplugging the o2 sensors changes it to 13.5:1. My question is does it do that through the whole range, or only closed loop area. I hate the lack of info available for the Vic fuel injection. Do they have ve table like the hd? I wish there was a tuner like the power vision available for the Vic's.
H-D has a great ECM and race tuner.
Vic is stuck in the 60's with there ECM technology.
The best thing you can do is do all your performance addon's and then ride down to The Vic Shop and have Rylan tune it. If your only going to air filter and exhaust you'll be a little lean. Buy a PCV and go have Rylan dyno it. Its only about a 4 hour ride and he can do it in a day. Or call Rylan now and talk to him about what you want from your bike.

02's tell the ECM what amount of fuel is not be burnt so the ECM can adjust accordingly with 02's un hooked there is no information so the ECM bike runs about 3 miles per gallon richer
 

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when i had mine dynod with the vfc settings almost off, lloydz filter , timing wheel , thrush packs, my af was all over, all rich especially low and top end, top end was in the high 11s for af, black smoke was a rollin out of the pipes!


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Here is a link to a thread where I copied and pasted email communication from the best in the business. Lloyd. This was regarding pinging and the causes of it which he thought could be from running too lean. As you'll see by reading the email communication, basically, you can't count on unplugging the O2s to do anything specific for you. It MIGHT go one way or it MIGHT go another way. There certainly isn't a set number that any bike will run at with them unplugged. Your best bet is to get a fuel tuner!

http://www.victoryforums.com/showthread.php?p=822697#post822697
Here's the problem I would have going in that direction. Has any aftermarket fuel processing supplier done a before (plugged in sensor) and after (unplugged sensor) test on AF ratios??? I've yet to see one. Any aftermarket supplier of a fuel processer is bound to steer you toward their product. Imagine if we found out the AF ratio went from 15 to one to 14 to one unplugged. They would lose a lot of business because that's what most of us would look for unless of course we put in cams, degree wheels, big bore kits and the like.
 

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Discussion Starter #10
Thanks for the input. I really wish I could keep the o2 sensors for elevation and temp. But have it run a little rich. I may go with some xieds. Idk.
 

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I understand that unplugging the o2 sensors changes it to 13.5:1. My question is does it do that through the whole range, or only closed loop area. I hate the lack of info available for the Vic fuel injection. Do they have ve table like the hd? I wish there was a tuner like the power vision available for the Vic's.
Thanks for the input. I really wish I could keep the o2 sensors for elevation and temp. But have it run a little rich. I may go with some xieds. Idk.
If you have the knowledge to adjust the AFR tables go with the PC-V w/ auto-tune. You can play with the tune all you want.
I've been adjusting mine while applying the trims.
 

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What the Vic Shop says

The problem is time and money. We've done some testing, yes. But after you run a couple of stock bikes with different combinations and one is running at 15.0 A/F and another at 14.8 and a third at 14.9 you kind of get the idea and start recommending fuel controllers. That and a person needs to get back onto paying jobs rather than playing around.

I can tell you that a stock bike cruises between 14.7 and 15.1 A/F with the 02's plugged in. Unplug the 02's and it cruises between 14.3.- 14.4ish area. Smack the throttle to get into the open loop and the high throttle positions are about 12.5ish.

So what I always tell people is unplugging the 02 will help richen it up a bit, but it will still be running really lean. A mistake that some make it running it at 100% throttle on the dyno - noting the 12.5 A/F ratio and then going to the forums telling everyone that their bike is running super rich. Yes, they run rich at 100% throttle because thats how the bike is designed. At cruise (5-20% throttle) that same bike may be at 14.9.

So back to OP's typical scenario: Yes, the bike will run just fine with a set of pipes with the 02's connected or disconnected. SUPER FRIKKIN LEAN, but yes. So then OP may get on the forums and say "well my bike without a controller runs FINE!" Well actually it runs o.k. now, but two things to think about:
1) How much better would it run with better fueling? A LOT actually. More throttle response, cooler motor, less popping, less engine damage, etc
2) What are the long-term issue with running so lean? I have opened up motors with 20-30K miles on them running like this and the exhaust valves look like craters on the moon. The motor really does take a beating when you run it super lean for a long time.

So again, motor runs really lean with both the 02's connected or disconnected - slightly richer when disconnected. Combination makes no difference really, it's just splitting hairs to compare. Get a fuel controller and richen up the cruise and lean out the Wide Open Throttle.
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