Board index Flathead Power-Technical Questions, Answers, and Suggestions Pans Piston preference ?

Piston preference ?

Moderators: Curt!, Pa

Post Thu Oct 22, 2009 8:20 am

Posts: 5
Anyone have any sage advice regarding pistons for my 50 Pan? Long story short, I'm buying new pistons and wonder if anyone can tell me if they've had good or bad experiences with any particular manufacture's pistons.
So far I've found the following online...
I'm thinking about going with the "MC" brand that are Moly coated, only because they advertise "feature cast construction with moly (moS2) coating which helps reduce friction and wear, while allowing adequate break in." They cost about $150 a set including pins, keepers, and rings.
Another brand is "The Keith Black 390 Hypereutectic alloy". They're listed as a performance pistion, with 9:1 compression where the MC brand is 8.5:1. They cost about $200 a set.
Wiseco has a 9:1 set for about $200.
V-Twin has a 8.5:1 set for for about $140.
Colony has a 8.5:1 set for about $125.

Any advice, or suggestions, is appreciated.

Jeff

Post Fri May 28, 2010 1:10 pm

Posts: 103
Location: Switzerland

I've had good experience with the pistons from V-Twin with Hastings rings (included). If you want to go with higher compression, the Wiseco pistons work well too.

Post Fri May 28, 2010 8:23 pm

Posts: 3130
Location: Central Illinois, USA
Jeff!

Stick with cast pistons if you wish to keep your balance close to original design.
Forged will drop your factor a bit.

Either way is a f*rt in a hailstorm compared to the cost difference!

...Cotten

Post Fri May 28, 2010 11:21 pm

Posts: 2687
Location: Los Angeles, CA
I am simply wondering where you can get new MC pistons? MC Supply went out of business 30 years ago. MC pistons were forged. Great pistons, but rattled until they warmed up.

Post Mon May 31, 2010 6:29 pm

Posts: 33
Chris Haynes wrote:
I am simply wondering where you can get new MC pistons? MC Supply went out of business 30 years ago. MC pistons were forged. Great pistons, but rattled until they warmed up.


I used to hang out at MC Supply down on Manchester Blvd about 40 years ago. Really good guys that owned and ran the place. Did you get down there yourself? I think one of the owner's name was J.C. Clausen but its been a long time. He had built "The Brute" and had it down there all the time. Dual Engine Knuck that he ran at Bonneville. Hand shifter, but only had 2 gears, low and high. Great place for parts back then.

Post Mon May 31, 2010 7:02 pm

Posts: 2687
Location: Los Angeles, CA
I used to go there weekly to pick up parts. Robert George was the builder/wrench of The Brute.
Image

Post Wed Jun 02, 2010 2:28 pm

Posts: 151
Location: Carver, MN

Boots, Chris, thanks for that little bit of history. I was unaware of the MC connection.
About the pistons;
There seem to be a number of NOS MC pistons around, and I am sure that V-Twin added the coating. The coating will help quiet the pistons down, but be sure you give them enough clearance for a forged piston.
I would stay away from the Keith Black because of their top ring placement. They are designed such that the top ring runs hotter than normal which makes them sensitive to extra engine heat. Something as simple as incorrect ignition timing can cause the top ring to butt together (lose all end gap) breaking the top ring land. They are high quality pistons, just unforgiving.
I would also stay away from the 9:1 compression ratio unless you are looking for more performance, and using a hot cam. Otherwise you may end up with a motor that's prone to pinging.
I don't see any pistons in the Colony catalog, but if they do sell them, it is very possible that they are the same pistons that V-Twin sells.
Almost all of the generic replacement pistons for Harleys that I have seen seem to work fine as long as they are set up with enough clearance. Here's what I'd do. Go to your local Custom Chrome dealer (or equivalent) and buy generic pistons for $28 each, add a $34 set of Hastings Moly rings, and then find a local hot rod shop to put the piston skirt coating on for maybe $40 for the pair. Just my 2 cents worth.

Post Wed Jun 02, 2010 4:59 pm

Posts: 2687
Location: Los Angeles, CA
Boots99 wrote:
I used to hang out at MC Supply down on Manchester Blvd about 40 years ago. Really good guys that owned and ran the place. Did you get down there yourself? I think one of the owner's name was J.C. Clausen but its been a long time. He had built "The Brute" and had it down there all the time. Dual Engine Knuck that he ran at Bonneville. Hand shifter, but only had 2 gears, low and high. Great place for parts back then.


Actually Clausen was C. B Clausen, one of the original Boozefighters. I think his partner was Jim Magnera or something like that.
http://www.antiquemotorcycle.org/TheMagazine/drag.html


Return to Pans