Re: 2014 GT535 - Project - "Ton"
Posted: Fri Nov 04, 2022 9:23 pm
Ace.cafe wrote:My general rule of thumb is that the gearing is correct for top speed if you can hit redline rpm in top gear.It doesn't quite hit redline/rev limiter in top gear, it's like 150-200rpm shy of it. I found out in 4th gear pulls yesterday it actually has a rev limiter. Haha.
However, for comfort purposes, some prefer other gearing.
It sounds to me like the 18 is good for your bike. I always downshift for overtaking anyway.
But that could be down to the tune or gearing. I did have the top end pretty rich at first at 12.7 target AFR. But since then trimming it back to 12.9-13 the map hasn't changed much at all in that area.
So I'm leaning towards gearing.
I still have a feeling I have to go a tooth lower in the front.
Done a little calculation with gearing commander. Especially knowing Taurim's bike hits 100mph/160kmh with the gear at 18x36 and the standard 130/70x18 tyre size. (639mm diameter)
Although I have a lot taller tyre using the Bridgestone accolade 4.00x18 (663mm Diameter) along with standard gearing at 18x36.
Larger diameter tyre is 24mm larger in diameter acting like taller gearing in itself. I'm basically chasing RPM sweet spots now.
Here's a graph I did on gearing commander.
So possibly switching to the smaller 17 tooth will just free it up that little more to reach redline in top gear. The rpms will also be in a sweeter spot just as the cams are starting to wake up at 3600rpm at our highway cruising speeds.
I'm not sure if it will hit "the ton" with the 17, maybe?
I'll give it a try and see how it feels when I give it a service/oil change/filter and check and re-set timing gear lash.
Can always change it back. Just a pain with that outer cover. Haha