It's all just opinions...
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And we all know what they say about those...
Well, certainly mine's worth no more than anyone else's, but here it is, but with a couple of qualifiers first.
1.) No bragging here. Just FYI. I started racing bikes in 1971, and held an AMA Pro license in MX for a few years, and a WERA Expert road race license for a long time. I also raced flat tracks, hare scrambles, and enduros at the expert level. I attended many MX and road race schools and assisted with instruction at both, too, along the way. Again, point is not to fluff, but to say that as many here have stated the learning of the proper skill sets will pay enormous dividends in improving your performance, and
without those skill sets you may not be able to take advatage of, or even properly notice the advantage of, lighter wheels or more horsepower...
If you have a good background in proper skill sets, read on.
2.) I mounted a set of forged
magnesium Marchesini's to replace the cast aluminum wheels on my Aprilia Tuono, and the handling difference was so staggeringly obvious that I almost couldn't quantify it. It was like a whole new motorcycle... And most importantly, and often not mentioned, the lighter wheels
made the suspension work so much better that I thought someone had secretly revalved both ends while I wasn't looking.
3.) I have done lots of engine work on lots of bikes... All I can say is be careful where you head when you go down that road. Which fork you take is ultra-dependent on what kind of riding you do. If it's on the track, going for peak power is usually okay (though not always if you ride only tight courses). If you ride on the street you are almost
always better off pursuing more torque across the rev range. The exception to that rule is street drag racing, of course. Literally any other sort of street riding, especially if it involves curves, torque is the better path...
4.) Often forgotten is making the engine (and chassis, but more on that in a moment) as
responsive to your needs as possible. Getting accurate throttle response, linear power deliver, minimizing driveline slack, smooth clutch engagement and operation, etc. Me, I can't stand what catalytic converters do to throttle response so for me they have to go first, though right after getting all the slack and friction out of the throttle assembly and linkage, etc. You want the engine to react to exactly how and what you want it do based on your riding style and skill level... This is one of those places where playing with flywheel weights can pay dividends for some. That said, some like engines with heavier flywheels and slower spool-up, while others like the engine to come on like a light-switch. Find what you like and go for it, but don't forget to try new things until you
know what your style is. It takes time, and you have to be honest with yourself.
5.) Learn to tune the chassis the same way - where is most responsive to
your needs and riding style. Some like super-quick steering and the front end planted like it was in concrete. Others like super-stable and maybe even some slight front end push at the limit. Some like the suspension so stiff you would swear it was made of solid cobalt steel, while others seem to like it to feel like it was made by Serta. Some like steering dampers (and know the proper way to use and tune one), while others can't stand them. A bike needs to handle like you like before you can notice gains from any sort of hop-ups, be it motor or chassis.
Now, all that said... Here's my opinion on the wheels vs. motor question.
Wheels.
That is if you have all the other figured out first.
Wheels not only help with reducing weight, but also improve suspension action
dramatically, and I do mean
DRAMATICALLY. I'm not talking about going from cast aluminum to forged aluminum. There's a nice difference there, but not a dramatic one. Go from aluminum to magnesium, or better yet, to carbon fiber, and there is a monumental handling difference. The real reason is because almost all the large weight reduction is out at the rim where it makes the most difference.
This is also why they help so damn much with acceleration and braking, and why they often have a far greater effect on handling feel than lighter brake rotors do. Lighter brake rotors only reduce weight down around the hub where it is harder to feel the difference. Super-lightweight wheels reduce a ton of weight out at the rim extremities where you not only can feel it far more easily, but also where it has the most actual and real effect in gyroscopic precession, etc.
As for durability... For most of us here I would not worry about forgecd magnesium or carbon fiber wheels. I think most here take good care of their bikes, and do proper maintenance, and more importantly, inspect their bikes carefully a lot. I also think most of us here ride well enough to avoid the obvious road irregularities that can damage
ANY wheel.
Carbon wheels are stronger than anything else out there, period. They are probably stiffer, too, which is why you don't see more MotoGP teams use them IMHO. As sticky as the tires are there, and as hard as those guys ride them, they may need a bit more modulus of elasticity in the structure between the axle and the tire contact patch just to allow some less abrupt and fatiguing feedback... But that's another subject.
Me, again... As soon as MotoWheels gets in the set of BST's they have backordered for me a set will be on my Hyper. BTW, I have an "S" with forged aluminum Marchesini's...
Maybe that's the best way I can answer the question with my personal opinion...
Hope you can find something useful in all this gibberish.
Dallara
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