KTM Forums banner

1 - 13 of 13 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter #1
Hey All, I have a 2015 SD 1290R with arrow de cat, akra slip on, sas delete, k&n air filter and akra tune. So basically the same as full akra exhaust. Bike dynos at 162 hp and 98 lb ft.

My buddy with the same bike with motohooligan airbox (similar to Rott) de cat, and dyno tuned with power commander Is making the same HP and TQ

not sure I have much to gain doing this? Any insight if this would produce gains over current setup?

Thanks
 

·
Registered
Joined
·
122 Posts
In theory the Motohooligan airbox should provide the conditions for bigger numbers than your setup. That's because the stock airbox is kinda crappily designed. Velocity stacks are too tall. With your setup the bike's ability to breathe is much better.

So I guess the stock headers might be what's holding it back. The Akra full exhaust isn't just fancy titanium to save weight, it has a lot to do with capturing resonance waves and what not. Airflow. The stock headers aren't engineered for max power output, the Akrapovic ones are.

What's the gas quality like in your region?

Ever had a need to synchronize your throttle bodies?

Decent quality motor oil?

Etc.
 

·
Registered
Joined
·
8 Posts
Discussion Starter #3 (Edited)
The gas quality is typically 91 and I get ethanol free when possible. Always use motorex 10w50 full syn I have not synced throttle bodies and have 20,000 miles on bike...may be time to do that.
If I knew the bike would pick up 10 hp + then might be worth it to install rott stage 3 but then a power commander would be necessary or a tuner. I’m sure there would be some midrange gain but not sure how much

looking at the numbers again my bike actually makes + 2 HP over the motohooligan setup with dyno tune, same dyno
 

·
Registered
Joined
·
812 Posts
Yo
The gas quality is typically 91 and I get ethanol free when possible. Always use motorex 10w50 full syn I have not synced throttle bodies and have 20,000 miles on bike...may be time to do that.
If I knew the bike would pick up 10 hp + then might be worth it to install rott stage 3 but then a power commander would be necessary or a tuner. I’m sure there would be some midrange gain but not sure how much

looking at the numbers again my bike actually makes + 2 HP over the motohooligan setup with dyno tune, same dyno
You will not see a marked difference if anything at all with the Rotty set up. Don't know the reason for the disrespect on the stock airbox? Unless you have a flowbench to actually test stuff you shouldn't be spreading misinformation. Short velocity stacks only help raise the peak HP to a higher RPM number .... doesn't promise actually raising HP.
PS: this was my specialty - airflow


Get one of these and then we'll talk ... warning there is a steep learning curve.
 

·
Registered
Joined
·
24 Posts
Have you been able to compare the dyno charts? Is it possible they match hp and torque only at max? My understanding is that the airbox increases power in the midrange quite a bit, which wouldn't be reflected by max numbers. Just a thought...
 

·
Registered
Joined
·
812 Posts
Airbox tuning is in itself quite an undertaking. The factory has forgotten more than we will ever know on the subject of their own engines. There is a well known brit who takes his Rott airbox equipped SDR to a dyno ... look it up on youtube. He was disappointed for the amount he spent ... the dyno guys knew their stuff however and did a few tweaks to gain some ponies for him. Which would have been done anyway.
We have had this discussion before on plenty of threads here. Boils down to this: modern engines have no more room for shade-tree mechanic improvements. V.E. Volumetric efficiency is so high that any "improving" usually hurts the power band somewhere else or harms overall, the exception is mapping.

Little known fact is that if you look at a dyno chart there is without exception a torque/HP cross-over at 5250 RPM give or take a couple hundred. Torque wins below 5250, HP takes over after 5250 ... always. There is in every case a trade-off between HP and torque ... RPM can and does solve this but street engines do not turn that fast (yet).
 

·
Registered
Joined
·
8 Posts
Discussion Starter #7
Thanks for the feedback, i do have both charts so I can look to compare midrange. I just don’t think the cost is worth the change at this point. I will stick with what I have

I appreciate all the insight
 

·
Registered
Joined
·
1,264 Posts
I think many folks believe a modification such as the Rotty (or Mh) airbox is an end unto itself when it really does little unless used in the correct combination with other mods.
As Sparty said, the factories have forgotten more than most of us will know about these things. One of the mags tested an expensive titanium exhaust system and the power gain over stock was zero.
 

·
Registered
Joined
·
60 Posts
I have an 18 sdr with pcv, full akra, k&n, dyno tuned - while not apples to apples, my buddy has a 17 sd-gt with full akra, pcv, rotty airbox/stacks - and we're within 2hp/ft lbs of each other....I have seen dyno's where the Rotty fills in the akra 5k rpm dip (my actual bike dyno shows too, and his doesnt)...so I have considered getting a Rotty airbox just for that fact - given 4-6k rpm torque is used a lot...so may or may not help top end max hip numbers a lot but does appear to help considerably in the mid range.....we're at 6k' altitude so we're only doing 154hp / 93tq...not in any hurry as bike runs bad *** at present and I dont necessarily want. the noise of the Rotty airbox (loud af on my buddies bike)
 

·
Registered
Joined
·
14 Posts
I really like the intake howl of the Rotty airbox and I'm very very sensitive to loud exhausts. I did leave the sound insulation on the underside of the tank, which according to Internet Wisdom, should help as it's reportedly REALLY loud if you remove the insulation.
 

·
Registered
Joined
·
326 Posts
I really like the intake howl of the Rotty airbox and I'm very very sensitive to loud exhausts. I did leave the sound insulation on the underside of the tank, which according to Internet Wisdom, should help as it's reportedly REALLY loud if you remove the insulation.
Wow, so folks are removing their under tank insulation as well? That is something I would never consider (or do, frankly). I am about to swap boxes funny enough from my Rotty to a Motohooligan over the Christmas holiday. Just personal preference on "build quality" and frankly if its neither/or as far as power gained or loss...it does not matter to me. I am ever so slightly hopeful it does cut down on some of the overall noise, as I also have an Austin GP1 I have modified a bit to be quieter.
 
1 - 13 of 13 Posts
Top