back to basics
We run TZ750s and RZ350s here and in Australia and there are some issues that remain the same.
First off, porting and pipes change the EFFECTIVE compression ratio at different points in your power curve.
Second, you have to get the squish clearnace right before you do almost anything else. if say your base gasket is too thick or the barrels are taller than spec ( or at the upper limit) then your squish band may be too wide. A tall squish band tends to increase the probability of detonation, so it pays to get it right. there are posts all over the internet on what "right' is, so speak to your favorite tuner.
Increased compression improves the bottom and mid range but tends to hurt the top end because of increased pumping losses. The trick is to find a compression ratio that works best for your type of riding. You may want to try a couple of different inserts to get to what works best for you.
Also keep in mind that different head shapes work at different parts of the RPM curve. Narrow squish works at the top end and broad ones for lower down, so feel free to experiment with different domes and see what works for you. Ignore all the hype and what other people do. We all ride differently and what works best for your riding style is the way to go - not what someone else uses.
Race bikes aren't quite the same as quads. We run long straightaways so we can't take as much compression as you guys, so we lose out a little of that mid range. We also can't use as much ignition advance at the top end, so we use ignition boxes that run more advance down low and less as the revs go up. Dyna do a programable CDI box for Banshees. WOLF probably do one as well. Now we're talking bigger dollars, so get the basic set up right first.
On TZ's historicaly stock bikes set up very carefully run faster and longer than all the trick ported high comp, super doodad machines. Make usre that what you have is working perfectly with the right jetting and compression and iginition advance. jetting two or three sizes off costs more HP than most accesories. Timing is the same. get it right.
A worn chain will cost you 1 to 4 hp at the rear wheels and may wear out sprockets or leave you stranded.
VP and Sunoco both do a range of fuels. We use VP C12 for most motors if we can get it. We also do a mix of Sunoco 100 unleaded and their 115 Octane, but my preference is to not mix anything other than oil and fuel and for that I use an Accu-Mix jug, available at www.accu-products.com
Avoid octane boosters like the plague. they are hard to mix accurately, add nothing in the way of power and really are just an expensive form of paint stripper.
Checkout any of the replacement dome guys for estimated compression pressure and the fuel you'll need, but try C12. If you are feeling rich, get a drum of the latest VP race gas MR8 or ultimate and feel the extra half a horsepower.
Check fuel:air ratio by readig the plugs or better still pull the heads and check. Unleaded leaves carbon and is impossible to read unless you are an expert. It also needs hotter plugs to burn off the soft carbon film.
So with race gas you should see a light gray or brown (depends on oil) and be prepared to go harder (colder) on plugs - say B9EVX in platinum or b10 if the plug shows signs of overheating. You can also use B9EGV or B10, but try to stay away from regular plugs with 1.3mm electrodes.
Life is a learning experience - feel free to experiment - you never know what you will learn - and keep reading too.