Crankcase opening dimensions needed ?

[Mohawk]

Hi Guys,

Does anyone have a 250 crankcase minus its block at the moment that they could measure for me ?

I need the width of the cylinder base openings left the right & front to back, I assume both sides are the same.
Plus I need the web thickness between the holes.

if anyone happens to have a 250 piston complete with rings & wrist pin that they could weigh accurately it would be appreciated. I have found a note somewhere that they are around 167grams complete, just need that confirmed.

Thanks

Chris.

[garth285]

will any measurements from a 08-12 engine help you?

[Mohawk]

I believe the crank cases are the same on the pre-gen & next-gen, so yes that should be fine. Thanks

[Mohawk]

Bum, any joy with the Tahoe measure ?

[Petrolh34d]

I'll see if I can be of assistance

[Mohawk]

Originally Posted by Petrolh34d

I'll see if I can be of assistance

Many thanks Petrolh34d.

[Mohawk]

BUMP

[bruce71198]

Originally Posted by Mohawk

BUMP

Do you still need these ?

[Mohawk]

yes please

[Mohawk]

Come on you teasers, someone must have one in bits. Also need the thickness of the bridge between crankcases.

[Mohawk]

Bump

[bruce71198]

Originally Posted by Mohawk

Bump

[IMG][/IMG]

[IMG][/IMG]

I'll weigh a piston assembly and post later.

[bruce71198]

Originally Posted by Mohawk

Come on you teasers, someone must have one in bits. Also need the thickness of the bridge between crankcases.

[IMG][/IMG]



That's the piston, pin, circlips and rings.

[Mohawk]

Hi Bruce, thanks for those, much appreciated.

[Mohawk]

So as I suspected, my new big bore liners will need a little metal removed from the left & rights sides where the liner cutouts are, but loads of room front to rear.

Thanks for the complete pisyon weight too. My big bore ones will weight 180 grams complete, (132gm bare), so 20 grams up on stock, but still lighter than the JE (139gm bare) or Wiseco (152gm bare) versions, which appear to work with stock rods.

Anyone know how deep the cylinder cut outs are in the side walls of the crankcase ? By that I mean from the top gasket face to the bottom of the scolloped area.

[Mohawk]

Just an avatar test

[bruce71198]

how big are you boring this engine?

[Mohawk]

66mm for 282cc using ZZR600 liners but having had them fitted to a spare block, then discovered the 250 liner is narrower at the bottom.

So thanks to your help, I now know I need to widen the cutouts slightly left to right, but they are fine front to rear. Then I remembered that the new liners are 3mm taller than the 250's so need to know if I need to trim the length !

[dcj13]

Your avatar pic looks just like your profile pic.

[bruce71198]

Originally Posted by Mohawk

66mm for 282cc using ZZR600 liners but having had them fitted to a spare block, then discovered the 250 liner is narrower at the bottom.

So thanks to your help, I now know I need to widen the cutouts slightly left to right, but they are fine front to rear. Then I remembered that the new liners are 3mm taller than the 250's so need to know if I need to trim the length !

I widened the cases with a die grinder and carbide bit. It was relatively easy and didn't take to long. 3mm should clear the crank, if not clearance it with the die grinder.