Hey guys, I have an '05 cbr600f4i with a dominator exhaust and performance air filter. I recently bought a pcv, and I'm getting an auto tune module for it and wanted to ask some questions like how do i set it up? Do i get it set up and run the bike with it on attached to the laptop, or do I take it on a ride and does the auto tune do the work? Also, I am aware a dynotune would be better, but im not looking for performance mostly just to improve my ride and keep it from running too lean or rich. What would be the best AFR?? Any help would be appreciated

 

Can't help you on how to tune but I can say, from having this done...
You're not going to gain much and, in my opinion, they're a waste of money. The guy that tuned mine was a rider before a bad wreck and is now a tuner for some rider in some series so he was not an amature.
The AFR the factory computer is reading is going to be just fine for any riding the bike will do.
When I had mine DynoJet dyno tuned I only gained somewhere around 2-3HP. The only place I say it improved is on how smooth the power came in.

 

Yes tuning fuel will get you maybe 2-3hp with your mods and PCV. Factory settings are fine for street-riding.

To get any useful and noticeable gains, you’ll need full exhaust with tuned header. Then need dyno-tune with ignition-map advance for high-octane petrol. It’s extra ignition-advance that gives you most gains as Honda set conservative ignition in case you get bad petrol out in middle of nowhere on super hot day. Or fuel-pump starts failing or injectors clog up.

With full-exhaust, dyno and ignition tuning, now you’re looking at +10bhp gain that may be noticeable, perhaps with stopwatch on racetrack. This +10bhp is worth about 0.25-0.50s/lap at Laguna Seca. But after cost of adding ignition module to PCV, you might as well get standalone programmable EFI system like Microsquirt with way, way more capability than factory ECU + PCV piggyback. You’ll be able to adjust:

- temp where cooling fan turns on
- redline RPM, per gear
- disable closed-throttle fuel-cut, makes for much smoother on/off/on transitions under max-cornering
- adjust MAP-sensor fuel-maps per gear (PC can only adjust TPS-sensor fuel-maps)
- adjust ignition maps, per cylinder and per gear
- knock-sensing for safety
- datalogging capabilities for extreme fine-tuning

 

I do appreciate everyones input! I'm not looking to turn this into a track bike, I'm just looking to smooth it out some and perhaps fix that surge whenever i cut off or on the throttle. My bike runs rather rich, and the surge it does when letting off or getting onto the throttle is more than a little noticeable, so I suppose my question is this: Will adding an autotuner fix the richness it runs at, and help tune out that surge?

 

No auto-tune won’t help that stumbling. Surge is not due to running rich. Bike might be running rich before you let off throttle. But the stumbling is caused by fuel cutoff, no fuel at all when throttle is closed. This is an emissions thing.

Then when you roll back on throttle, fuel is injected again and you get surge of power. Very annoying.

You can mess with fuel-settings all you want just before and just after closed-throttle. But there’s no way to defeat the no-fuel cutoff when you let up on throttle without changing ECU. It happened on my F4i, my ‘05 CBR600RR, ‘07 CBR600RR and my ST1300. Even tried Woolich to reprogram ECU on my ‘07 because they claim they got rid of closed-throttle fuel-cut. Nope still there regardless of settings.

Only way I got rid of it on my RRs was ripping out factory ECU and installing Microsquirt. I’ll be doing that on my ST next.

 

ST's are amazing bikes, my dad has one. Well, that kind of sucks. I'll just put up with it I suppose, I'll pay someone to tune the ECU at a later time and just ditch the pcv whenever that time comes. Until then I'll keep running it. Anyone know what AFR i should be shooting for?

 

Typically you only tune high-RPM WOT throttle sections where ECU goes into open-loop and ignores O2-sensor. So LOADxRPM in 100%x8000rpm+.
Factory mixture tends to be rich, so leaning out mixtures to 13.5:1 AFR gives max-power.

In partial-throttle, there may be some lean spots. Around 50-70% load X 4000-8000rpms. Add about +10-15% fuel in those ranges.

Exact data-cells to adjust and amount will depend on actual readings you get. Easiest DIY method is with datalogging wideband-O2. Then you just do couple of runs and record data on road. Then download data when back home, draw pretty graphs and make adjustments as needed. I've used wideband-O2 from TechEdge.au and they work awesome. Completely transparent with their circuitry and how it works along with excellent instructions and customer support. Here's their current DIY kit: https://www.wbo2.com/2j/2j9.htm . Standalone wideband-O2 better (and cheaper) than DynoJet's AutoTune module because you can carry over to other bikes, even tune carbs, and re-use with aftermarket EFI systems at later time.

sample datalog graphed

time 5629-5900 normal cruising with O2-sensor feedback, I've targeted 15.5:1 AFR for better fuel-economy
5917-6394 going up hill, downshifted 2-gears and goes into open-loop mode, more power @ 13.5:1 AFR
6400-6493 going downhill, let off throttle coast, then get back on throttle. Fuel gets cut off and zero exhaust to analyse. It thinks AFR is 380.98:1 due to all air no fuel. This is where stumble/surge occurs

One thing that makes off-throttle fuel-cut much milder is using mechanical throttle-cam with non-linear pull. Initial cable-pull is slow to make on/off/on transition smoother. Then it increases cable-pull as you twist throttle more. Look for "G2 Throttle Tamer"