Piston identification? Cr 500

[TheRealFatShady]

Just picked up two (NOS) pistons for a CR500.

Not sure what brand, OEM, Wiseco, etc they are.

No mic, but at least one is smaller (1mm approximately) than my new Wiseco 90.50mm piston.

Marks on them:

Piston 1: Inside says "1^" (actually it's an arrow above the one).
L (inside still)
4.10:1 - can't really tell the "." and ":" marks for sure (inside still)
"ART" - Inside of piston again

Top has "in" on it, but no other marks

Piston 2:
Inside = "ART" "=2" (= above the 2), "L" "495"
"In" on the top


Wiseco in the middle





I'm thinking OEM Honda 480 or cr500 84-89. Will need to check the bore.

Thanks

[SWIGIN]

Brand doesn't really matter but the 2 ART pistons are just a cast fatory replacement type piston. What matters to me at least is what they are made of and how they are made. I don't like cast pistons but thats just me.

[Vealmonkey]

I know the wiseco piston is a different brand than the other 2, but are they supposed to be for the same bike? Just curious cause that wiseco wristpin seems way smaller than the wrist pins for the other 2 pistons.

[TheRealFatShady]

It may be an illusion, but I thought that too.

Wiseco piston I bought is SUPPOSEDLY for 82/83 480R and 84-89 cr500r. Part numbers on stock OS pistons for both 480r and 500r are the same, so they should work....I'd think.

I thought the 500r pistons would NOT interchange, but it came in original box and even Wiseco has it listed for both models. If not, will sell these pistons. Will have to compare to my rod and stock wrist pin, but my 480 engine is at the shop....

[oldskool83]

84 500r piston prob not gonna fit 85-89, 84 was air colled like the 480

[TheRealFatShady]

I was wondering about the difference in cooling...these came from a liquid cooled bike as the seller also had a gasket set.

My Wiseco - just bought on eBay, says "Hon cr480 82-83; cr500 84-89 3564TD - 90.50mm" Replaces 554P6

[cr480r]

yes 500 pistons fit 480's. not even an issue