78 Puch Maxi, E50 bottom end
I've a korado top end, transfer ports matched and exhaust port widened a hair on either side. I've a 17mm bing widemouth on a magnum X intake manifold (pointing it forwards). I've 14x45 gearing, and a lightened 2 shoe clutch with paz springs. I'm running stock points based ignition, and I'm still on the original crank.
I rode the bike up to the welding shop in the city today, about a 10 mile ride (with earplugs). The bike performed admirably, idled easily at a nice low tickover, nice and smooth. It pulled decently from 0-7 or 8, then I could feel the bike vibrate as the clutch dug in and the thing would pull hard up to about 25. There the acceleration would let up a bit, and it would ease up to 30-32. Now, at that speed the engine is at a nice high rpm with the 14x45 gearing. I'm out for acceleration, and whatever top speed comes with it.
The owner of the welding shop modified my techno boss admirably, fitting it to the angled exhaust port on the korado cylinder like it was meant to go there in the first place. Now, the acceleration has changed slightly. It still pulls up to 8mph without me needing to pedal boost it (I'm 6'2" and 280, keep in mind). The bike vibrates as the clutch digs in, and it simply screams up to 24 or so, where once again the acceleration slacks off sharply and it eases up to 35.
Now, it feels like it should have more of a powerband, or perhaps what's happening is I'm feeling the midrange boost of the techno boss, and I need something with a higher RPM powerband. But I can't tell whether there's something else I should be considering, or whether the exhaust pipe could be holding it back. It does four stroke a bit at 35, so I may downjet a size to see what happens, but even so, the drop in acceleration rate from 24-35 has me wondering.
Any thoughts?