stroker crank

[bigbusabigbusa]

i think im going to add a stroker crank to my 1397 build. im not sure what size to go with. 2 mill 5 mill or larger this is a street ridden bike and occasional weekend warrior at the track. what size do you recomend and what kind of hp and tq can i expect from each size. thank you

 

[Commuta_Busa]

I've run 7.5 mill on the streets with no problems. The longer cranks tend to flatten out the toque curve. There's no specific hp/tq number based on stroke. Each stroke kind of end up with it's own cam/head setup.

The same holds true for oversized bores. I don't know of anyone that has just over bored and left the rest of the engine package the same to make a comparison. I've had over bores up to 4mill survive on the street. The cooling system does get very sensitive with over bores.

And before you ask, i don't know of anyone that has done a straight comparison between different rod lengths and/or pin position.

long story short.... the engine package/combo that you want should be based on streetability and your budget.