Bigger Headers on 2.5

Taz said:

So what was at the wheel? I am willing to invest somewhat in my R3R but I just don't want to go down a big rabbit hole where I p!ss away money like there is no tomorrow. Did you do a remap of the ECU? It seems like a Penner Tune or BT Moto picks up a lot of HP even on a stock bike.

I am trying to understand how much more the header might net me.

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Paul Bryant said:

182.5 RWHP.
The bike MUST BE Dyno tuned to suit.

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Paul Bryant said:

There's a lot of "interesting" opinions stated here.
We built a header for the 2.5, had it tuned properly, 215 crank HP. That's a 35% increase over stock.


No other mods.
So for those who say "just a header won't make much difference" you're way off base.

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2023R3GT said:

Interesting. where did you find an engine bench to measure crank numbers?

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Paul Bryant said:

There's a lot of "interesting" opinions stated here.
We built a header for the 2.5, had it tuned properly, 215 crank HP. That's a 35% increase over stock.


No other mods.
So for those who say "just a header won't make much difference" you're way off base.

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Paul Bryant said:

General concensus is there,s between 10-15% power loss through the drive train, depending who you talk to.
So by taking the real world rear wheel HP and calculating back by that % figure you get the crank figure.

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2023R3GT said:

general consensus on motorcycle shaftdrive losses is 20-25% - chain and belt have 10-15% losses

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