Okay, so I’m new to the sport bike scene. My other bikes have always been cruisers. I don’t have anyone around my area that I can really ask the question so I figured I’d ask you all. Is it normal for the throttle of the bike to feel a bit (not really sure how to put it) stiff at certain speeds. I mostly notice it in 5th gear if I’m doing about 52-60mph. It’s not really a resistance but just feels strange to me. If I accelerate it goes away quickly. Not sure if this is a user issue, a bike issue, not an issue. This has by far been my favorite bike (my baby, if you will) and I think I’m still in that “every small thing I do may screw it up” phase.
bike info: 2022 Suzuki GSX-R750
Mileage: ~450-475.
This sounds like a (normal) dip in your torque curve. It is just one of those things to understand about your machine and for you to master to gain maximum control with it.
If you look at many dyno curves you may see little dips in the torque line. Ideally that would be flat; same torque at any speed equals same acceleration force at any speed.
The probable reasons you haven't noticed on your cruiser are a) it is not tuned so hard, so the engineers had scope to design the torque curve to be flat (just knocked off the peaks with engine mapping), b) it does not use a ram effect, where the oncoming air is pressed into the air box, which creates resonances at certain air speeds and c) the volume of the air box will resonate at certain air flow rates (the main reason for torque dips), this is an effect called Helmholtz resonance, and your cruiser can accommodate a larger air box. It is less noticeable on cars (if any effect at all) because they can accommodate such large air boxes to shift that resonance away from operating speeds, but bikes are a bit more constrained in the range of their air box volumes.
It is a sheer luxury that sports bikes these days offer pretty much flat torque curves. In the days of carburettors, all sorts of strange effects could occur, and none so more than on 2-strokes. The engine of my KR1S could quite literally stall if you tried to run it between 5 and 5.5k rpm, like many highly tuned 2 strokes, and occasionally on smaller 4 strokes, as the intake resonance reaches a peak the intake air will pass through the carb, bounce back off the closing valve, pick up a second charge of fuel as it exits the carb the wrong way, and then picks up a 3rd charge of fuel once the intake port opens again. Result is 3 times over-rich and the cylinder stalls. Various solutions to this have been devised over time, "power valve" (RD 350), "rotax" (a rotary port), "reed valve" (RG250 I think? Rotax also moved to reed valves, AFAIK, but that rather undermined their founding name!!! 🤷♀️) and my own, KIPS valves on the Kawasaski.
So, think yourselves lucky that all we get these days with fuel injected 4 strokes is 'a slight hesitation'!! Or maybe ... we're not so lucky any more and all of that was "characterness" that's part of the thrill of the ride and somewhat missing these days .. take your pick!
Good luck with that then,
@22GSXR750 , and consider it part of your bike's 'personality' it sounds quite normal.
