Piston diameter?

[Parthe]

Bit of an odd question but what’s the diameter of a Rocket 3 piston?

2.3 or 2.5 will be fine, the measurement will be close enough for my needs.

“Why?” I hear you ask. Well because I want to make three gavels from them, obviously. Now aren’t you sorry you asked?

I’ve tried Google but it’s failed me.

 

[ozrider]

Bit of an odd question but what’s the diameter of a Rocket 3 piston?

2.3 or 2.5 will be fine, the measurement will be close enough for my needs.

“Why?” I hear you ask. Well because I want to make three gavels from them, obviously. Now aren’t you sorry you asked?

I’ve tried Google but it’s failed me.

Piston Bore is 101.6mm

 

[Mongler07]

You can easily come up with some basic math.
Most engines run a fairly square stroke to bore. So it's just a volume calculation.
Volume of a cylinder is V=πr2h
So
(2300/3) = 3.14r2h
So basically for the sake of your question h = 2r
I'm too lazy past this point so I checked it in wolframalpha and it came up with basically 101.1 but that's close enough for your whatever reason I assume.
Math is free online. Learn how to use it.
Beefy 4 inch piston

 

[R-III-R Turbo]

101.6mm (Rocket III)
110.2mm (Rocket 3)

It should be a filter question when signing up to the site!

 

[Mongler07]

101.6mm (Rocket III)
110.2mm (Rocket 3)

It should be a filter question when signing up to the site!

If I was an engineer on the design team for the rocket III, i would have made sure that the bore was 111.0mm
But at that time a 4.00 inch bore made more sense in our burger land.

 

[Parthe]

You can easily come up with some basic math.
Most engines run a fairly square stroke to bore. So it's just a volume calculation.
Volume of a cylinder is V=πr2h
So
(2300/3) = 3.14r2h
So basically for the sake of your question h = 2r
I'm too lazy past this point so I checked it in wolframalpha and it came up with basically 101.1 but that's close enough for your whatever reason I assume.
Math is free online. Learn how to use it.
Beefy 4 inch piston

Mathematics is freely taught in schools where I grew up and I’m very good at basic maths, but I learned volume calculations a very long time ago and I can’t work out how I would get the diameter even with your example. This is how far I got:
2300 = the engine size and it’s a three cylinder, hence (2300/3). Call it 800 for this example.

800 = 3.14r2h or 254.77 = r^2 * h

That leaves two unknown numbers, r and h but I have no idea how I’d work that out.

> So basically for the sake of your question h = 2r

I have no idea how you made this leap. Where would I get that information from?

I’m genuinely interested in how the mathematics works here.

 

[Mongler07]

Mathematics is freely taught in schools where I grew up and I’m very good at basic maths, but I learned volume calculations a very long time ago and I can’t work out how I would get the diameter even with your example. This is how far I got:
2300 = the engine size and it’s a three cylinder, hence (2300/3). Call it 800 for this example.

800 = 3.14r2h or 254.77 = r^2 * h

That leaves two unknown numbers, r and h but I have no idea how I’d work that out.

> So basically for the sake of your question h = 2r

I have no idea how you made this leap. Where would I get that information from?

I’m genuinely interested in how the mathematics works here.

IDK, it was very early in the am. you can't figure that this way. I already knew the stroke so in my going to bed minds just assumed you could.

 

[Parthe]

IDK, it was very early in the am. you can't figure that this way. I already knew the stroke so in my going to bed minds just assumed you could.

I'll work on my mind-reading!

 

[Parthe]

Bit of an odd question but what’s the diameter of a Rocket 3 piston?

2.3 or 2.5 will be fine, the measurement will be close enough for my needs.

“Why?” I hear you ask. Well because I want to make three gavels from them, obviously. Now aren’t you sorry you asked?

I’ve tried Google but it’s failed me.

OK, with thanks to everyone who responded. I was always told to show my working out so for future querants:

Formula for working out the volume of a cylinder: is V=πr2h

Rocket III	Rocket 3
Volume: 2300	Volume: 2500
Stroke (Height): 101.6mm	Stroke (Height): 110.2mm
3.142 * r^2 * 101.6 = 2300	3.142 * r^2 * 110.2 = 2500
3.142 * r^2 = 22.638	3.142 * r^2 = 22.686
r^2 = 7.205	r^2 = 7.220
r = 2.684	r = 2.687
diameter = 5.37cm	diameter = 5.374cm

|\/|

 

[R-III-R Turbo]

OK, with thanks to everyone who responded. I was always told to show my working out so for future querants:

Formula for working out the volume of a cylinder: is V=πr2h

Rocket III	Rocket 3
Volume: 2300	Volume: 2500
Stroke (Height): 101.6mm	Stroke (Height): 110.2mm
3.142 * r^2 * 101.6 = 2300	3.142 * r^2 * 110.2 = 2500
3.142 * r^2 = 22.638	3.142 * r^2 = 22.686
r^2 = 7.205	r^2 = 7.220
r = 2.684	r = 2.687
diameter = 5.37cm	diameter = 5.374cm

|\/|

Ehm. I know we're having fun here with maths and all that. And I don't want to step on anyone's happy... but in the interest of avoiding misinformation, the bores are 101.6 and 110.2mm, the strokes are different than bores.
Bores & strokes (diameters or radii, & heights) of cylinders aren't interchangeable in volume calculations.

Also the 2300 displacement is actually close to 2294cc and 2500 is close to 2458cc.
Pedantic but the difference here will lead to a relatively massive difference in the bore diameter.
But anyway there is no need to backwards calculate what the bores are as they are listed on Triumph websites and also in their manuals for these bikes.

Sorry for rant, my OCD has been triggered!