Being new here, I thought I might as well add a story. I picked up my CB550F for not a lot of cash probably about 19 years ago. Tidied it up & tuned it. I'm a mechanic by trade although not full time on bikes.
Plugs, points, tappets blah blah blah.... balanced the carbs. Sort of rode ok, but put a passenger on the back and look out.
Bogged down from standing starts like you wouldn't believe. Loaded up and took ages to get going. It was nearly rideable with one up, but sluggish low down.
I decided it's time for compression test. #1 40psi; #2 40psi; #3 40psi; #4 40psi. There's trouble here I said. Off with the head, bores looked fine, valve & seats? No problem. Put it back together & played with valve timing, I was sure it mustn't have been set right to begin with. Rolled it back a tooth & the engine wouldn't turn. Forward a tooth & had the same result.
I put a degree wheel on the crank & found the inlet valves weren't closing til 45 degrees abdc!!!! This is a problem.
Got onto some bike wreckers, found a standard cam & slipped it in.
What a transformation!!!! It idles, pulls smoothly from standing start even with two up.
I don't know what was in the head of the guy that fitted this monster cam. By the time it got it's breath, a standard bike would be a block & a half ahead.
I reckon Mr Honda's fellas got things pretty right to begin with. The lesson here I guess is don't mess with things unless you're really sure what you're doing hey? Good luck with your mods fellas.
