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If all you change is the stage 1 exhaust, do you really need to unplug the 02 sensors? I ask because I hear and read there is not much difference in stock and stage 1. The long range plan is PC5 and Lloyd's air filter, but for now I just have the pipes. Kyle is only close enough 2 times a year at Myrtle Beach, so timing is a big influence on when and what I do. I don't have enough cash right now to do everything before the rally in 3 weeks and I don't want to wait 5 months until he comes around again to put on the pipes. Unplugging the 02 sensors for 5 months is also not part of the master plan as I do most of my riding during this time. What do you think? Just asking an open question......
 

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qwhat Rylan had to say
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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Rylan Vos
The Vic Shop, Inc
 

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I know with my tune he spent more time tuning the low mid and upper RPM/throttle position than the wide open throttle. The air/fuel varies with even the slightest change in throttle/rpm.
 

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Vj pretty much summed it up with that one...all bikes are different and unplugging the o2 will help if you need it. You will have to unplug them when you get the pc5.
 

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If all you change is the stage 1 exhaust, do you really need to unplug the 02 sensors? I ask because I hear and read there is not much difference in stock and stage 1. The long range plan is PC5 and Lloyd's air filter, but for now I just have the pipes. Kyle is only close enough 2 times a year at Myrtle Beach, so timing is a big influence on when and what I do. I don't have enough cash right now to do everything before the rally in 3 weeks and I don't want to wait 5 months until he comes around again to put on the pipes. Unplugging the 02 sensors for 5 months is also not part of the master plan as I do most of my riding during this time. What do you think? Just asking an open question......
1. Install pipes.
2. unplug 02's if you have excessive popping or any backfiring.
3. Ride and assess.
4. Leave unplugged, or plug them back in, depending on assessment.

I did it on my Judge after modding my pipes and getting some pops and poofs. Still had a little here and there after unplugging but WAY better. It has almost gone completely away since my timing wheel install. Unplugging and plugging only takes a minute so try it out.
 

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You don't have to unplug your 02's. You will get popping more than likely and unplugging the 02's just made it worse on my bike. Just will have to learn to shift at a higher rpm.
 
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