NRHS Stage 2 for 07 XB12R

[mike lowary]

Why tune to 14.7 to accommodate a narrow band O2 sensor? It will run cooler and have better throttle response at about 14.2. Plus, those sensors are not the most trust worthy. I only keep the O2 sensor active to sense and report a lean condition with a CEL in the event something mechanically goes south. In CL the ECM will just compensate for a problem without you knowing about it (with the factory CL settings anyway). Add a baro sensor for air pressure compensation. Using a NB O2 sensor for sensing elevation is a terrible idea. You have intake air and engine temp sensors to adjust for temperature. What else would the ECM be able to (and need to) adjust for in CL?

This is an interesting write up, even though it's about Harleys: https://www.drdyno.com/AIM_2010-07.html

A lot of people disagree with you on this. Makes sense to me though.

 

[outthere]

I've been running open loop for a few years using wideband O2 sensor and never an issue. AFV set to 103. Bike not street ridden though.

 

[34nineteen]

I can see why more knowledgeable riders like upaero and outthere run their bikes that way. They appear to both be extremely knowledgeable and well versed in the operation of their bikes and able to troubleshoot and resolve problems if and when they arise.

For the rest of us, myself included, running like that is like giving a machine gun to a monkey. I can figure out *most* but not all issues on my own, but even I know that I can easily get in the weeds when given too much control over the tuning. I know just enough to be dangerous, and would need a lot of patience and hand holding if I ran my bike in that configuration. Pre-canned tunes are best for me.

YMMV. Just my $0.02.

On another note....hey outthere, what exhaust is that? It looks like you married a Force to a SS Drummer? I like it!

 

[mike lowary]

I've been running open loop for a few years using wideband O2 sensor and never an issue. AFV set to 103. Bike not street ridden though.

Mike check this out. Shaved 4.5 lbs off the drivetrain with this setup. You need it.

 

[Cooter]

Primary Porn

 

[lawdog]

Did you guys change your timing at all from stock? I have left mine stock but Hammer Performance suggested Harley stock maps may be too aggressive for the big bore kits due to the higher compression.

 

[cvc]

Mike check this out. Shaved 4.5 lbs off the drivetrain with this setup. You need it.

What primary is that? And do the do multiple ratios?

 

[mike lowary]

Did you guys change your timing at all from stock? I have left mine stock but Hammer Performance suggested Harley stock maps may be too aggressive for the big bore kits due to the higher compression.

Yes the ignition timing maps were changed. The stock and race timing maps are ok up to a certain point. What’s your compression ratio now? Did you get the 30 degree reverse dome pistons?

 

[cvc]

Should have blown up the pic before asking. That’s what I get for looking at stuff on my phone.

 

[mike lowary]

What primary is that? And do the do multiple ratios?

Evolution industries billet clutch assembly and engine sprocket. As far as ratios go, they make engine sprockets with many different tooth counts. You can go up or down one tooth on the engine sprocket and still use the stock primary chain.

 

[lawdog]

Yes the ignition timing maps were changed. The stock and race timing maps are ok up to a certain point. What’s your compression ratio now? Did you get the 30 degree reverse dome pistons?

I am running the stock timing map right now. Looking through old posts it looks like I played around with timing about 10 years ago, wasn't satisfied with any changes I made or the race timing maps, and went back to stock. I have the 30 degree reverse dome pistons with a target compression ratio of 10.5:1. I have never actually measured it.

 

[mike lowary]

I am running the stock timing map right now. Looking through old posts it looks like I played around with timing about 10 years ago, wasn't satisfied with any changes I made or the race timing maps, and went back to stock. I have the 30 degree reverse dome pistons with a target compression ratio of 10.5:1. I have never actually measured it.

Several factors come into play with this. Raising compression, 30 degree combustion chamber, and getting the squish band dialed in. All of these things require less timing to make power. Especially the 30 degree chambers and squish band. The 10.5:1 compression isn’t really high enough to make such a difference. In my case it would because I’m at almost 12:1. I could whip you up a better base timing map if you like. Let me know. What year is your 12?

 

[lawdog]

2009 XB12R with BUEZD

 

[outthere]

I do like that primary set-up. The Norton could have used something like that.

Running open-loop still lets the ECM correct for lean conditions. I seem to help bottom power more than anything. The bike pulls a well-running open loop.

That is Force/Drummer combination. It Fits Dean's muffler also but it's in a bit of a bind so I'll give this a go this year.

 

[upaero]

Running open-loop still lets the ECM correct for lean conditions. I seem to help bottom power more than anything. The bike pulls a well-running open loop.View attachment 15205

Actually, in open loop the ECM will not correct for a lean or rich condition. However, the O2 sensor can still be active to inform you about sensed lean condition with a CEL. That way you can do something to fix the problem instead of having the ECM try to compensate for it without you knowing.

 

[outthere]

^^^^^always learning