Hello everyone. I've been a reader of this forum for a long time now and have gotten alot of great information. I've got a 08 Ultra that I've put over 20k miles on and I recently added the PC-V from Fuel Moto along with their SE air intake and SE slipons that I already had. I'm pleased with the overall performance but the afr between 2k and 4k is alittle rich for my taste. I've noticed a marked increase in part throttle snap and response by leaning up this range by a few percent in the PC-V programming. Who else has done this and what was your average percentage drop? Part throttle response is the most important factor to me as WOT is fine. I also noticed on their map there are no changes in timing. Has anyone played with this? It really runs great and I'm just fine tuning trying to get the most out of the PC-V without getting the autotune.

 

Anyone? This thing is fun to play with but maybe the autotune would be more fun. I'm starting to obsess.

 

I don't know how it would translate for the '08, but I had my '07 running largely zeroes in the cruise range (2000-3000rpm @ 5-20% TP). On my bike with the stock cams that translated into about stoich (14.7:1), which is about where the ECM was running in stock form with the O2 sensors connected and no PCIII or PCV. First thing, though, before messing with the base map is to save the original to your computer. Then alter it as you see fit and save the result to another filename. To change a number of values on the map, select the ones you want to change, then hit the pg-up/pg-down key to move the value up or down 1%.

Fuel Moto tunes for cooling and throttle response in the cruise range, and that means your mileage will usually decrease, probably around 10%. You could cut the positive values in half and try that, as this would not cause the bike to run excessively lean, then keep going until you're happy with the result. You may lose a bit of throttle response, but I've never been able to feel the difference.

Go by your senses. If it is too lean it may detonate, surge, and/or run hot, as well as hesitate if excessive. Surging without hesitation when cold is not a problem, IMO, but I would back off if it does so when warmed up. If you have installed an oil cooler you can lean the AFRs more since it will help to dissipate engine heat.

Another trick to consider is to add a switch, which will allow you to select between two maps. Keep the original rich map so you can select it when the going gets hot, then run a leaner map most of the time for better mileage.

Changing the values in the base map is guesswork without putting the bike on a dyno or using a sniffer, but I do think you can tune the PCV by the seat of your pants with a good result. Just listen and feel for the telltale signs of excessive leanness. Just don't change any of the values above about 40% TP, as you don't want to hinder performance when you nail it.

Then again, you could add Auto-Tune and eliminate the guesswork altogether, but that's not really necessary for most riders. If you are an incorrigible tweaker and/or plan on making changes to your hardware (cams, different mufflers, etc.) you might find it very useful.