Pits in cylinder plating...is this OK?

[KTM Mike]

Take a look at the attached pics of the pits in the plating on this cylinder. this is from my son's 99 Kaw KDX. I dont know if this is the factory plating, or if it has been replated at some point in its life. These are definetly pits, and are not material adhered to the cylinder (aluminum transfered onto cylinder wall for example).

In showing this to others, I have been told that US Chrome sends out a notice saying that some degree of pitting is normal - is this the sort of thing they are referring to? Or is this beyond that? I have had a couple clyinders done by them in years past and did not see any pitting - nor did I get the little note they send out saying some pitting is normal - so I dont have a feel for just how much pitting they say is OK or not.

The cylinder appears to otherwise be in decent shape - certainly not new, but I would say good enough to not worry about a replate yet. If it were not for these pits, I would simply replace the piston and rings and call it a day -

What do you guys think - is this the normal acceptable pitting US Chrome (and perhaps others?) refer to - or is this something else going on?

Thanks for the help

Mike

 

[RM_guy]

Some pitting is normal, in fact is desirable because it traps oil for better lubrication. I haven't seen that amount of pitting but if the compression is OK then use it.

Pitting can be a function of the casting porosity and this casting may have been more porous. Also Kawasaki plating is not the best and may not have filled the pores very well.

As long as the plating is not flaking off and the compression is good then run it.