Bonneville America Forums Forums Technical Forums Performance Mods another Dyno run

this is my old duny print out from july last year

it was 108 main jet and adjustable needle with clip on top notch

and there is printout from run I made today

changes from last year:
- fatter heavier rear wheel (loosing power feature )
- new cluch(barnett) and stiffer springs(EBC)
- rubber bellmouth airbox intake(from Jenks Bolts)


diffrence -----68.4hp was 67.12hp
--------------57.46ft/lbs was 54.37ft/lbs

118 main jet (four sizes up)
needle rised clip 3rd position from top

will go next week to get same printout in same format as the first one with RPM on the bottom

Keep in mind that your data used a DIN correction factor, which as a general rule will show higher numbers than the SAE CF benchmark used in the USA. In other words, DIN and SAE numbers are not a directly comparable. DIN corrects to more favorable environmental conditions than SAE does, hence the higher numbers.

I think the point is, YOU WON'T MAKE THOSE NUMBERS IN THE USA!

(instead of 68.04 & 65.89, THEY COULD BE AS LOW AS 68.01 & 65.87)

Yes, that is funny! However, the difference is more like 5%. And we'll save the discussion of positive & negative CF's for another time...

Thanks for the comparison. I think you showed what you wanted to and I appreciate seeing the difference.

Grzegorz, when I get a chance I'll put yours and anyone else who has done a dyno recently, up on the dyno table including the pics etc.

I will make a short note about the DIN and SAE comparison even though there isn't much in it anyway. Excellent numbers btw mate.

staffo