Some installation notes and first impressions of the Akrapovic GP shorty full system exhaust and Rapid Bike Evo controller
Because it is unlikely that anyone will read the whole thing, I will start with a big Thank You! To Mani from Motomillion
. He helped me make an informed purchase decision, answered the phone each time I called him with questions during the installation, and never referred me to the Search function. Highly recommend Mani and Motomillion as a vendor.
Summary of changes
- Akrapovic full system, with stainless steel headers and titanium GP style shorty can
- Rapid Bike Evo fuel controller
- Brock’s Performance PAIR valve plug
- 2015 belly pan
Take time to empty the tank. I didn’t have enough time to ride before the rain set in, and had 2 gallons left in it. Not a major impairment, but it would have been easier to install it back if it was empty. Disconnecting the servo cables was easy. Removing the rear servo motor was a pain in the rear. After rerouting the brake fluid reservoir, it was supposed to just slide off, but I could not get enough clearance. I didn’t go all out like the guy who took apart the whole bike (Marcel?) to get to it, but I ended up lifting the subframe by removing the lower bolts and loosening the top. Not a big deal once I figured what to do. Removing the headers was like pulling wisdom teeth, through the anus. The biggest pain was the wire bracket that holds the radiator and oil cooler both at their bottoms and attaches to the engine. The screw is hard to access, and Loc-tied. I did not see an easy way to remove the radiator fan, and could not get a great clearance. With lots of patience and cussing when the patience ran out, it was done.
I was surprised by how light the headers were. At first I thought that they have sent me the titanium ones. The whole system, including headers, collectors, link pipe, muffler, springs, clamps and all, weighs 11 lbs, just a little more than the stock can alone. The instructions were better than most I have seen, and I supplemented them with 650ib’s video of the installation. I have a good arsenal of tools, but nothing that would have allowed me to torque the flange bolts after mounting the headers, so I hooked the springs and torqued the flanges before installing the headers. The little link pipe between the two center headers took a bit of fiddling to connect, but eventually it got there. Just take your time. After attaching all the springs, I was left with two extra. They are supplied in case they are needed for the muffler, and in my case, they aren’t. One thing that the instructions don’t say is that you don’t need the graphite gasket supplied with the slip on. The stock link pipe is a smaller diameter than the Akrapovic, so it is not needed for the Akrapovic headers. Plugging the PAIR valve and installing the Sprint P08 filter was easy and straightforward.
Rapid Bike Evo
The instructions supplied by MotoMillion are great. Probably the best instructions on modding I have seen. I had a couple of minor questions during the installation and Mani was very helpful. All in all, a very straightforward installation.
2015 belly pan
With the cat gone, I wanted to give the rear a more finished look. I picked a used 2015 belly pan from a local performance shop. The right side attached with no issues. The left side needs a 2015-specific mounting bracket. I have one on order from Max BMW.
I demonstrated it separately to my both sons and my wife. Each of them would jump back when it fired up. Whoever said it is not much louder than stock has a different definition of “loud” than my family. It IS loud. I wasn’t aiming at that, but well, here we are. The sound is mean. The exhaust gas comes with some force. Standing up 6 feet behind, it would ruffle my hair. My hat literally blew off from the hanger I had behind the bike.
Pulling out of the driveway, I stalled. Then the RB learning took over and it fixed itself, so take-offs are no longer a problem. There were some pops and burble when downshifting, but after 50 miles they mostly cleared. There are still some at around 3000 RPM when coasting or going downhill. I am hoping they will be cleared.
Under normal riding, the bike pulls much, much harder. Before buying the BMW, I test rode the Tuono, and I remember the feeling of raw power and ferocity. The BMW in stock form, up to 9,000 rpm, is almost docile in comparison. Not anymore. The bike is transformed. It is louder, stronger, badder. It is much more engaging.
Shifting improved. At moderate acceleration and less than full throttle, the quickshifter is now much smoother, both up and down. Especially going up and down between 2nd and 3rd gears.
There are some vibrations felt in the frame and clip ons. I am thinking of putting rubber washers around the hanger bracket.
Is it worth it
Absolutely. It looks great, sounds great, and adds a considerable amount of power in the mid range. Since I broke the "One change at a time" rule of modding, I cannot say which change contributed the most, but all together, the improvements are undeniable. The only consideration is that the loud noise at idle may be disturbing to family or neighbors.