[crazyflyboy30]

I tell you one thing about a cam that is bigger is better.
Back in the day I put a Suzuki 230 Quad sport cam in a Suzuki 125 Quad Runer engine and put it on the Quad Sport frame and that thing was about has fast it was with the 230 engine only thing was that the 125 did not go crazy till it was screaming then it like insane.
It was very fun to ride and sorry to say that the chain jumped off and badly bent the output shaft and after that I don't remember what happened to it.

 

[polman500]

HO is a marketing gimmick. Put HO stickers on and your machine will "feel" a lot faster. Similar concept to slip on "performance" mufflers.

 

[latebird]

Doe's fuel injection make an engine more powerful? No! Fuel injection is a more precise method of metering fuel meaning you can have a more linear power output which equates into more fuel economy and more consistent acceleration, but if a carburetor is properly engineered and tuned, it will perform as well as fuel injection and can be more economical to operate. Cool the incoming air to make it more dense and add some water vapor and an engine with a carburetor can provide better performance and economy. The deciding factor it the mechanic who set up the engine.