Just my thoughts, if what your asking. I think it's possible to get less performance, with a bigger engine, if you have a large restriction. The restriction is increased, base off what engine can, or wants to do.
I noticed after my engine swap, from 155cc to the BD 175cc, that the rpm range has changed. The 155cc rpm range was much higher. Took while to get there, have no issues hitting 9500, on flat ground 10,000 going down a slight hill. But the 175cc, don't think I've hit over 9k. flat or down hill. But the power is much more in the lower rpm range. I think to this point, my top speed, was in the 155cc. around 37mph However, would take me 1000 feet to get there. And the engine just screaming.
The new 175cc, I'm hitting 30mph in 300 feet. best I seen the 155cc in that distance, on same track, was 17mph. So huge difference. But if just base it off top speed, could say 155cc, out performs the 175cc. Since top speed in 175cc is 33mph so far.
But that clearly is not the case. the 175 crushes the 155.
I meant to, wanted to. Actually test runs with the old 155cc, before I swaped out to the 175cc. However, couldn't do it. But the test strip I have up for the 175cc, is part of our normal ride. And do recall, seeing how fast I could get in the flat run. and normally was 16, and best was, 17. On top of that, wasn't at a dead stop. That's running going around a turn. So bet would be less than that, if ever tested from a dead stop. The 175cc, is crazy quicker then the 155cc.
So just saying, don't base everything off top speed. Not a good base line to start off with.
My test length is 338 feet. Longest straight flat run I got at my place. Not perfect flat, it's on a dike. But serves it's purpose.
If you can do test runs at that length, from dead stop, love to hear what you get. if your getting over 20mph, then say, you got a good increase. Just basing it off my modified 155cc.
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