Teflon coated pistins

[mad dog]

I doing a rebuild on my 94 fxr evo. Sucked a valve seal, broken valve spring. Putting in new cylinders and harleys teflon coated pistins..
bottem taken apart and clean.
Does any one have any experience with these pistins?
any advise apreaciated.
respectfully,   jlj

[hdbikedoc]

Have used since hd sub up work fine always bore to hd specs and use torque plates

[stroker800]

   I have had them in a few Ski Doo snowmobiles over the years,,,seem to work as well as any other piston..I've found that the teflon burns off of the domes,,teflon melts at 700 degrees...I would like to try pistons with teflon skirts and ceramic coated tops...I know HD only coats the skirts and never heard of any problems.
Dave

[Phu Cat]

Is the teflon on the outside of the piston or impregnated into the metal?  Even if it is very thin, it seems like as it wears away it might create an excess clearence problem.  How's that work?

PC

[wfolarry]

When fitting the pistons you would measure the piston - the coating. Some pistons have a clean spot on each side for this. Some don't. If you measure over the coating it will be wrong. Do like hdbikedoc said & you'll be fine.

[mad dog]

Thank you all for input. looking forward to the breakin.
jlj