Long awaited post. Sorry for the delay. The Yoshimura is a good alternative option to the Akrapovic system. Each have their pros and cons. Will be discussing each along the way.
First set of data. The blue line is bone stock average blue. The green line is only installing the yosh system, and flashing the Akra map in ecu. Still retaining the stock air filter and lid/snorkel. The yosh makes more front side power BUT less peak hp and over rev, with a slight insignificant increase in peak torque. I suspect with stock map in ecu the AFR would've been leaner resulting in an even larger loss of peak horsepower.
The second graph shows the gains from installing the K&N filter and modifying the lid. Green is same run from before just the yosh and akra map. Red is after the filter install and lid mod. Still no PCV tuning just parts swap, at this time. You can see nice gains from filter and lid like always. Biggest bang for buck gains on these bikes. Denoted by the Akrapovic testing previously too.
The third graph shows actual gains from PCV tuning. Red is final numbers after tuning and all the mods vs no tuning (blue).
The final graph shows the Akra vs Yosh pipe, with same mods and being "tuned". The yosh makes better front side gains and mid-range (blue). The Akra makes more peak hp with better over rev (green). The yosh makes more peak torque though.
So final gains on this yosh system with the other stated mods are 2.32 hp, and 3.03 ft/lbs increase. Strictly bolting the exhaust system on with no other mods will loose power.
At this point in time it's a toss up/personal preference for which to use on your build. The yosh is about a full pound heavier than the Akra. The yosh system is considerably louder than the Akra system. You might have trouble at some tracks around the country with noise requirements with the yosh. The dB killers in might sneak it by, it would be close, needs to measured with professional equipment. The drawback to the yosh for track use is adding the weight up high under the tail where it doesn't need to be. The yosh for a street bike is a good choice, in terms of appearance and noise (if that's what you are looking for). I have a very nice map built for the yosh system now. It will be included with an exhuast or PCV purchase if so desired. Any other information/questions let me know.
Links to purchase below.
KTM RC390 Yoshimura Dual Exit Exaust
or
KTM RC390 Yoshimura Dual Exit Exaust
First set of data. The blue line is bone stock average blue. The green line is only installing the yosh system, and flashing the Akra map in ecu. Still retaining the stock air filter and lid/snorkel. The yosh makes more front side power BUT less peak hp and over rev, with a slight insignificant increase in peak torque. I suspect with stock map in ecu the AFR would've been leaner resulting in an even larger loss of peak horsepower.
The second graph shows the gains from installing the K&N filter and modifying the lid. Green is same run from before just the yosh and akra map. Red is after the filter install and lid mod. Still no PCV tuning just parts swap, at this time. You can see nice gains from filter and lid like always. Biggest bang for buck gains on these bikes. Denoted by the Akrapovic testing previously too.
The third graph shows actual gains from PCV tuning. Red is final numbers after tuning and all the mods vs no tuning (blue).
The final graph shows the Akra vs Yosh pipe, with same mods and being "tuned". The yosh makes better front side gains and mid-range (blue). The Akra makes more peak hp with better over rev (green). The yosh makes more peak torque though.
So final gains on this yosh system with the other stated mods are 2.32 hp, and 3.03 ft/lbs increase. Strictly bolting the exhaust system on with no other mods will loose power.
At this point in time it's a toss up/personal preference for which to use on your build. The yosh is about a full pound heavier than the Akra. The yosh system is considerably louder than the Akra system. You might have trouble at some tracks around the country with noise requirements with the yosh. The dB killers in might sneak it by, it would be close, needs to measured with professional equipment. The drawback to the yosh for track use is adding the weight up high under the tail where it doesn't need to be. The yosh for a street bike is a good choice, in terms of appearance and noise (if that's what you are looking for). I have a very nice map built for the yosh system now. It will be included with an exhuast or PCV purchase if so desired. Any other information/questions let me know.
Links to purchase below.
KTM RC390 Yoshimura Dual Exit Exaust
or
KTM RC390 Yoshimura Dual Exit Exaust
