Sean a bad diod will cause the alt to put out less than 11V which won't charge the battery. Bad diods are found very shortly as the battery goes dead real quick.
As for the spark... if it runs smoothly without jumping and humping the spark is good enough. Sparks either spark or don't! Remember a small yellow spark is just as serviceable as a giant blue one.. The fuel don't know the difference. Once lit (no matter what lights it) the fuel burns the same..
You've heard of "buyers remorse" Well the opposite occures when a guy buys something and gets real giddy about his purchase!! Examples could be pooty-poot mufflers, cold air systems, throttle plates or even new shocks.
Big JIm <img src="/forums/images/graemlins/pfft.gif" alt="" />