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Discussion Starter · #1 ·
Hi everyone, sorry to open yet another thread on this topic, but I want to share the results of this weekend's efforts installing the Akrapovic catless stainless steel headers with the stock muffler and stock airbox. I also installed a PowerCommanderV.

For years, I've been thrilled with the power and torque of this bike- it's fun as heck to ride, but the only thing I've hated is the strangled low-rpm, low-speed choppy throttle. I ride a lot around town, so I spend a lot of time blipping the throttle and low-speed maneuvering around. There's been times I've gone to pull away from a traffic light and the bike has flat out died! This is a little dangerous, and worse embarrassing! I got rid of the flapper valve a while ago, and got a good tuneup from a dealer I like but still for whatever reason I haven't gotten around to finally installing these mods.

Well, I'm kicking myself because some combination of the free-flowing exhaust and Powercommander gizmo has transformed the bike. I took a quick mixed street/highway ride around town today and the low-rev strangled feel of the stock system is gone. There seems to be a little more kick on the pants, but that's not what I was after- I wanted a smoother overall power delivery and this setup has delivered! At low speed burbling up between a line of cars in traffic I don't have the same feeling the bike might die if I whack the throttle open. If I'm downshifting to slow for a turn or come to a stop, there's a pleasing smoothness as the engine slows down (so I can prepare for the turn or whatever)- it doesn't feel like it used to, where it was like a guillotine blade dropped and killed the fuel delivery. Gear shifting up and down at all speeds feels smoother and almost silky. The bike just feels like it's finally able to breathe.

Now, the funny thing is this is without any dyno tune or any scientific approach- I just plugged in the Powercommander and checked out the fuel map it came programmed with on my laptop- this is in the attachment, labeled "shipped-map". I went on the Dynojet website and the Akrapovic sites expecting I would find a map for "stock airbox, muffler plus cat delete headers" or something, but I couldn't find anything. I should have done my homework before the installation! Anyway, Dynojet has a map for "Stock Exhaust/Air filter" on their site, so I downloaded that.

The thing I don't understand is, the map that came with the unit,"shipped-map", has all zeroes (0) in the upper left quadrant. The map I downloaded, which is for my bike, has more positive numbers in the upper left. That means a richer fuel mapping in this problematical low-rev, low-speed region- right?

So, I uploaded the downloaded map (with the richer mixture) to the PCV and the bike runs great. (I know I should plump for a dyno session to really get the most out of the parts I bought). What I'm a little perplexed at is why did the PCV ship with such a different map from the one on Dynojet's website? I haven't tried the bike with the shipped map and at this point I really don't see the point. I'm wondering if anyone has had a similar experience.

I guess I might have gotten a similar result installing a Boosterplug but I was thinking I could find a PCV map for my specific setup so I said what the heck and bought the PCV. I'm happy I did but now I'm wondering what a proper dyno run and tuning session will get me


· Administrator
13,952 Posts
I'm not techy enough to comment in detail, but this is an excellent first post! Thanks for taking the time to write it. The 9T really does benefit from getting a good tune, Low speed performance on low throttle openings I always found were a little snatchy, the ECU tune completely cured this. I have flashed a Bren tune on mine and the difference is startling. As you say it's more about rideability improvements, but it really does improve the torque, especially in the mid to upper ranges. I wouldn't go back, and I expect the PC route does a very similar thing, albeit in a slightly different way.

I would guess that your bike would benefit from tweaking on a dyno as an experienced tuner will get the best out of your investment. I'm hoping other PC users will come along and give you better opinion than I ever could! LOL
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