Help with specs for oversize pistons

[andyak]

Going to have machine shop redo 2005 ar230 block - see mystery starting problem thread for some drama
- it has some scratches and will probably need to go to an oversize.

Machine shop says they need pistons (first have to figure how much to go overbore)
then get pistons here and the bring pistons and rings to them with block

- THEN he said they need the clearance specs from the manufacturer of the pistons - I have been looking all over internet and can't find these specs for .50mm (OEM or proX or 1.0mm oversize pistons proX) tried calling a proX dealer and just got voicemai l does anyone out there who has done this have this info? especially for the oem .50 mm over.

Thanks!!!

 

[Murf'n'surf]

The only help I can give you is look into RIVA Racing site. You might even call them for suggestions. www.rivaracing.com

 

[KXCam22]

The stock yamaha clearance specs should also be good for the oversize pistons. That is normal for them to require the pistons and the clearance before they bore. Cam.

 

[andyak]

Thanks. I did find the stock specs in a 2003 fx 140 manual.

Does anyone know why the later service manuals use final angle torque specs vs the earlier manual I found that just gives final torques for the head bolt nuts?

 

[Murf'n'surf]

Do you need a 2005 shop manual?

 

[andyak]

I have the 2005 ar230 Ho manual my engines are not Ho. I have a 2003 fx140 manual. They differ in head torquing techniques. Newer uses final torque to angle. Older uses just a final torque value. I think torque angle is now preferred way but want input from others thanks