The iconic superbike : Yamaha YZF-R1

[The Spin Doctor]

More valves generally also means more valve area, which is one of the big reasons they do it. The valves are circular, so if you imagine fitting circular valves into a circular cylinder head you can 'cover' more of the bore with a greater number of smaller valves.

That in turn means you have less restriction on gas getting jn/out of the cylinders. One of the limitations on engine power is how quickly and easily you can get the fuel in and the exhaust out. More valve area means you can shove it in/out more quickly so you push the revs higher and the peak power up.

5v doesn't intrinsically make an engine peaky, bit it does facilitate tuning for high peak power at peak revs, which has the effect of making the engine revvy. Chicken and egg kinda thing.

You can also close the exhaust valves sooner, which means less fresh charge chasing the burnt gases out the exhaust ports.

That's why the FZ was so frugal. My 1990 version averaged 55 mpg, would hit 60 mpg without too much trouble and got close to 70 mpg on one Bank Holiday Monday run back across France when I couldn't find an open filling station for 200 miles. Nicest engine on anything I've owned.

My 92 WN GSX-R750 was more powerful (according to the spec sheet) and was far more peaky, but struggled to top 40 mpg. One German autobahn run got it down to just under 30 mpg.

[Yorick]

More valves generally also means more valve area, which is one of the big reasons they do it. The valves are circular, so if you imagine fitting circular valves into a circular cylinder head you can 'cover' more of the bore with a greater number of smaller valves.

That in turn means you have less restriction on gas getting jn/out of the cylinders. One of the limitations on engine power is how quickly and easily you can get the fuel in and the exhaust out. More valve area means you can shove it in/out more quickly so you push the revs higher and the peak power up.

5v doesn't intrinsically make an engine peaky, bit it does facilitate tuning for high peak power at peak revs, which has the effect of making the engine revvy. Chicken and egg kinda thing.

You can also close the exhaust valves sooner, which means less fresh charge chasing the burnt gases out the exhaust ports.

That's why the FZ was so frugal. My 1990 version averaged 55 mpg, would hit 60 mpg without too much trouble and got close to 70 mpg on one Bank Holiday Monday run back across France when I couldn't find an open filling station for 200 miles. Nicest engine on anything I've owned.

My 92 WN GSX-R750 was more powerful (according to the spec sheet) and was far more peaky, but struggled to top 40 mpg. One German autobahn run got it down to just under 30 mpg.

You must ride like a gurl. I used to get my GSXR1000 down to 17 mpg

[The Spin Doctor]

You must ride like a gurl. I used to get my GSXR1000 down to 17 mpg

Yeah, but you have bigger bores than me

[Bigjawa]

More valves generally also means more valve area, which is one of the big reasons they do it. The valves are circular, so if you imagine fitting circular valves into a circular cylinder head you can 'cover' more of the bore with a greater number of smaller valves.

That in turn means you have less restriction on gas getting jn/out of the cylinders. One of the limitations on engine power is how quickly and easily you can get the fuel in and the exhaust out. More valve area means you can shove it in/out more quickly so you push the revs higher and the peak power up.

5v doesn't intrinsically make an engine peaky, bit it does facilitate tuning for high peak power at peak revs, which has the effect of making the engine revvy. Chicken and egg kinda thing.

You can also close the exhaust valves sooner, which means less fresh charge chasing the burnt gases out the exhaust ports.

That's why the FZ was so frugal. My 1990 version averaged 55 mpg, would hit 60 mpg without too much trouble and got close to 70 mpg on one Bank Holiday Monday run back across France when I couldn't find an open filling station for 200 miles. Nicest engine on anything I've owned.

My 92 WN GSX-R750 was more powerful (according to the spec sheet) and was far more peaky, but struggled to top 40 mpg. One German autobahn run got it down to just under 30 mpg.

Most of the Slingshot and WN on GSXRs had carbs that were far too big, same with the 1100.

[Le_Fromage_Grande]

You must ride like a gurl. I used to get my GSXR1000 down to 17 mpg

Yeah, but you have bigger bores than me

Nah, you ride like a gurl, I've never got 50mpg out of an FZ, and my early R1 used to do about 20mpg, I ride like a twat.

[The Spin Doctor]

You must ride like a gurl. I used to get my GSXR1000 down to 17 mpg

Yeah, but you have bigger bores than me

Nah, you ride like a gurl, I've never got 50mpg out of an FZ, and my early R1 used to do about 20mpg, I ride like a twat.

Looks like I'm outvoted. I'll get the wig

[Tricky]

Seems an appropriate opportunity for a bit of picture-whoring to me
I bought mine brand new in 1999 , was the bike I did my first ever trackday on back in the days when I used to ride to them, it gave me 15k trouble free miles of real fun before I sold it

[Le_Fromage_Grande]

Most of the Slingshot and WN on GSXRs had carbs that were far too big, same with the 1100.

That's probably correct, it's led to people running huge flat slides on mildly tuned big Zs and then complaining about throttle response

[Scootabout]

It's the superbike whose name springs to mind first. Possibly because "R1" is a lot quicker to say than "GSXR1000" for example.

[KungFooBob]

Same number of syllables as Gixer tho'