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Yeah that rpm rise is a pretty standard thing with bikes, it's why you need to design in a lot of overrev in the engine, so you don't ruin your life by banging into the limiter as you tip it in at full throttle at or near peak power. It feels pretty cool as well for some reason, pinning the throttle open and then having the revs rise and the bike squirm as you hoon through a fast sweeper. It's what it's all about.
You also get the opposite effect where the revs seem to stay the same as you pick the bike up whilst accelerating hard, almost giving a CVT type effect as the effective gear ratio increases with the speed for a short moment.
If there is an actual CVT in there, then no, the ratio will be controlled according to the torque output to keep rpm almost constant regardless, unless you're above the speed that the CVT essentially locks out at its maximum ratio.
Examples:
I seem to recall the tyres effectively add lean angle too. This makes sense since the lean angle controls the cornering speed first, and the tyre grip (compound) essentially determines at what point (in terms of g force, so lean angle again) the tyre slips.
Presumably this also increases the gear ratio effect discussed above, the greater the lean angle the greater the difference in tyre circumference at the contact patch and so the more the revs rise and fall from lean angle alone.
Racing tyres generally have more aggressive profiles, and they will be different sizes between manufacturers in particular, so in a racing situation these differences can have a significant effect. A larger circumference rear tyre has quite a lot of knock on effects in terms of not just the head / steering angle and trail, but also the swingarm angle and resulting suspension geometry there (sag, then linkage ratios) which also affects the anti squat from the chain drive.
You also get the opposite effect where the revs seem to stay the same as you pick the bike up whilst accelerating hard, almost giving a CVT type effect as the effective gear ratio increases with the speed for a short moment.
If there is an actual CVT in there, then no, the ratio will be controlled according to the torque output to keep rpm almost constant regardless, unless you're above the speed that the CVT essentially locks out at its maximum ratio.
Examples:
Yeah that could be a bit misleading. But is also correct, as slicks don't fundamentally change the geometry of the bike, ride height etc, so don't affect the handling per se. But you will find you can brake harder, accelerate better and grip better in the corners as well as accelerate out of them without the bike wanting to snap away from you (it doesn't cure it, but it helps a LOT)
I seem to recall the tyres effectively add lean angle too. This makes sense since the lean angle controls the cornering speed first, and the tyre grip (compound) essentially determines at what point (in terms of g force, so lean angle again) the tyre slips.
Presumably this also increases the gear ratio effect discussed above, the greater the lean angle the greater the difference in tyre circumference at the contact patch and so the more the revs rise and fall from lean angle alone.
Racing tyres generally have more aggressive profiles, and they will be different sizes between manufacturers in particular, so in a racing situation these differences can have a significant effect. A larger circumference rear tyre has quite a lot of knock on effects in terms of not just the head / steering angle and trail, but also the swingarm angle and resulting suspension geometry there (sag, then linkage ratios) which also affects the anti squat from the chain drive.