Identifing Westbend US820 pistons

[mcbob]

Well fellas the more i see the more confused i become as shown below are 3 pistons i bought as second hand units through Ebay and two Copperhead pistons





Now the rings for these pistons are different so maybe some-one can fill me in a bit of the Westbend US 820 as regards the order or use of the pistons shown
The one with a window in the side i understand and it has two thick rings
The one with the boost ports has them larger than the Copperhead piston and in a different position ie lower.
The other one has tool steel rings.

The second lot of pics show two different Copperhead pistons

[mcbob]

Now the Copperhead pistons





The piston on the left is the origional piston from my Copperhead and the one on right the replacement unit sent by Dave now the second one has thicker rings than the first, my engine was one of the early ones and built around the April 07, 2007.

Now another problem when ordering bits is there an ammended and updated part number listing to cover these difference's , ie if i was ordering for the first copperhead piston are these rings still available as there thinner than the second lot or does one have to buy a piston assy complete as the thinner rings are no longer available ?

I realise that upgraded components would be built into current production but to me it's confusing not knowing whats what and whats been replaced same with conrods and being so far away it becomes drawn out and frustrating to have chased and got the wrong item.

McBob.

May the Westbend US820 Gods have mercy on little ol me.

[louie figone]

Bob-

First picture, the two left side pistons are West Bend pistons with two .062 rings, the one on the left has been modified for a modified transfer port runner, the center piston has been modified for an eight ported cylinder, the piston on the right is a Wiseco with two .024 rings, no longer made. The two West Bend pistons should have the part # cast into the bottom of the crown and the Wiseco will have Wiseco cast into the bottom of the crown. There were a lot of different shops making pistons for the early kart engines, Wiseco, Fuller, MSM and others.

The picture of the Copper Head pistons is the current single ring piston that Dave had US Motor do for the Copperhead and the Vintage 820. They can use a single .062 ring or two .030 steel rings in the same ring grove. The rings are made from a 1mm (.039) ring and surface ground to .030. The rings are available from Dave Bonbright. All the current pistons will have US Motor Power cast into the bottom of the crown with the part # cast into the inside of the skirt. The two ring piston is still available and used in the industrial engine. The single ring piston is only in the kart versions that I am aware of.
Hope this helps you out.

Louie