hey guys, I'm tossing up whether to put a duke 390 underbody GPR power core on or the new GPR ghost line. what do you guys think is better? sound and power wise?
I am looking at the ghost line, I am more interested in power over sound, it's a track bike for me. But I am going to wait and see what formula390 comes up with. I would much rather buy this side of the ocean.
Dean, weren't you the one selling the AHM exhaust? What exactly are you after? I think that system sounds amazing.
Hey guys,
I received the Akrapovic slip-on exhaust (KTM PowerParts) recently and just noticed it says it's for a '14. I assume it will work with the '15 as well?
There haven't been any dyno results published from either as far as I know. I have my exhaust designed, but won't be releasing it until such time as I can finish dyno testing and be able to publish performance data. Without dyno results, you are just crossing your fingers and hoping. From all accounts without remapping, any modifications to the intake or exhaust will result in a potentially dangerous lean condition. The Power Commander V will be out in about a months time, and my intent is to release my exhaust to coincide with that so that mappings for it will available concurrently. It's possible to have the dealer map your stock ECU with the Akrapovic mapping, which would be an improvement, but still not optimized for any modifications to intake or exhaust.
He is still in the production/test phase I think. Dyno time coming next weekend. I think there are a few of us in line when he is ready.
Yea im waiting for your exhaust as well Matt. i want something that keeps the stock position. since we have to wait for the PCV to release anyway before putting any exhaust on (besides the akra) i decided im just gonna live with stock for now. once the PCV is available i am assuming/hoping you will have a map for ur exhaust PLUS a K&N air filter with the billet airbox mod
My understanding is the exhaust was initially designed for the Duke and was then mounted on the RC for the cup bikes. It was the only available slip-on at the time (tho Arrow and a few others followed soon after the RC was released). There is no difference for the RC as there is still only one model year, with the Cup and Street versions being virtually identical but for the upgrades the Cup bikes got with the WP suspension, exhaust, bodywork, ECU mapping, and the restriction plate.
Thanks, do you happen to know the stock exhaust weight?
Yeah... 3.79 metric tons!!! No actually 5.2kg / 11.5lbs. It's a SERIOUS chunk of steel and weight to be sure. The first time I pulled it off it shocked me with how much it weighed even with my EXPECTING it to weigh a lot.
A1VW2NV cut his open, and you can see why it weighs so much:
The routing in the can lengthens the total exhaust length and provides the dampening... but to total length doesn't need to be nearly this long. Of course, stock exhaust systems are all about noise mitigation with the hope it doesn't hurt power too much. That's 180 degree turn it has to make with the exhaust gasses however isn't doing the motor ANY good. That's just basic fluid dynamics theory!!! You just don't, or at least SHOULDN'T, do that!
Thanks for that info. Very interesting to know as I weighed the Akrapovic slip-on exhaust and with all mounting hardware included plus the Akrapovic hanger eliminating the passenger peg (minus the Duke 390 bracket which isn't used) it comes out to 10 lbs, 12.6 oz. Or with just the exhaust system and no mounting hardware 9 lbs, 6.5 oz. $1000 and I thought there would be a bigger weight savings. It's no big deal as I will be saving enough weight elsewhere on the bike.
He is still in the production/test phase I think. Dyno time coming next weekend. I think there are a few of us in line when he is ready.
Im really not looking to wait too long, there are plenty of good exhausts on the market and the ghost is product by a company with lots of resources, I thank its a great option. I'd be interested in a hard timeline and I'm sure im not the only one that would appreciate an eta on the exaust.