GSX550ES con rod length needed

[Nobbsie]

Does anyone one know the heart to heart length of the gsx550es con rod. I cannot find it anywhere.
It needs to be the Es model or any similer model with the 51mm stroke, as I believe the Australian e model had a shorter stroke of 40 something.
Cheers
Nobbsie

[Grumph]

Does anyone one know the heart to heart length of the gsx550es con rod. I cannot find it anywhere.
It needs to be the Es model or any similer model with the 51mm stroke, as I believe the Australian e model had a shorter stroke of 40 something.
Cheers
Nobbsie

They're all 50.6mm stroke. WTF do you need this info for ? If you're looking for interchangeabilty, big and small end ID's are more important.

[Nobbsie]

The reason I need to know is because I already know the other sizes but need to know the length to see if i can fit them in a different engine

[Grumph]

The reason I need to know is because I already know the other sizes but need to know the length to see if i can fit them in a different engine

That's the easy bit - either space the barrel if they're longer - or machine the required amount off the barrel if they're shorter....

[Blackbird]

That's the easy bit - either space the barrel if they're longer - or machine the required amount off the barrel if they're shorter....

Exactly that! A lifetime ago, I had to machine the barrel of a 60's Tiger 100 500 to turn it into an oversquare supercharged 350, fitted with a short stroke crank for drag racing.

[Grumph]

Exactly that! A lifetime ago, I had to machine the barrel of a 60's Tiger 100 500 to turn it into an oversquare supercharged 350, fitted with a short stroke crank for drag racing.

I suspect you'd have done better - and certainly had a better combustion chamber shape - if you'd started with a T90...

Putting a 600 yamaha rod and pin in an Aermacchi single requires machining a half inch off the barrel - but it lets you put the engine further forward.
And it's reliable....

[Blackbird]

I suspect you'd have done better - and certainly had a better combustion chamber shape - if you'd started with a T90...

Putting a 600 yamaha rod and pin in an Aermacchi single requires machining a half inch off the barrel - but it lets you put the engine further forward.
And it's reliable....

It had a modified Tiger 100 head but head shape isn't so critical with a supercharger and nitro. Keeping the barrel and head on the crankcase was the big worry l

[Nobbsie]

Yea but I would like to compare the length to another rod, to try get the longest stroke. I'd like to do this without having to buy two different rods

[Grumph]

Yea but I would like to compare the length to another rod, to try get the longest stroke. I'd like to do this without having to buy two different rods

Well in the old days, you'd go and poke around a wreckers yard...

Rod length has nothing to do with stroke except at the design stage. If you want the longest rod for geometric reasons, fair enough.

[Nobbsie]

I'm not currently in the position to go to a wrecker. Or near anyone I know of with one to measure. So I was simply asking for a piece of information I thought one of you might know, so I can continue my ideas wether they are right or wrong.

[F5 Dave]

So, how's that working out for you?

[Nobbsie]

Could be worse, looks like I'll use a different crank, with different rods which will fit better with less work