1098 piston diameter

[Matt Tomkins]

Hi all,
I have been forced to strip my spare engine down, after the new crank spun a bearing and consequently filled the engine with swarf.
i was always under the impression that the pistons in it were standard size. there didnt seem to be a discernible lip when i last had the head off, so i left the top end totally in situe when i replaced the crank.

unfortunately, however, on removal there is a small lip toward the front of the cylinder so either an agressive hone or total rebore is on the cards.
nevertheless, the number 1 piston is rather mullared (looks like someone's had a go at it with a screwdriver at some point :/

my question: although the piston has no markings of a + size, it is a 5-ring piston and therefore unlikely to be original.

is there a table anywhere of piston sizes for rebore?
and at what amount of hone do i need to replace the piston?

Regards

Matt

[bmcecosse]

How on earth did a 'new crank' spin a bearing??????? If there is any lip - it needs reboring - honing will not be a long term answer.

2.542" is the STD bore size. Rebores are 10/20/30 etc on that. Get the pistons before you decide..... But you NEED to find out WHY the crank 'spun a bearing' ??? Did the engine spin over easily by hand before you started it??

[IslipMinor]

Hi Matt,

I have a set of internal micrometers and am waiting delivery on a hone, if that is what is required.

Not too far away, as you know!