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forged vs cast
Posted: March 20th, 2008, 5:40 pm
by 100hp honda
if i had my way my machine would have forged or billet crank, rod and piston- unfortunatly that aint a option for me....hell i would even like billet cases but that aint gonna happen either. i want to get a discussion going on everybodies preferences
Posted: March 20th, 2008, 6:37 pm
by Ported&Polished
Do you want a discusion or an argument? I say cast pistons rule. You can keep your siezcos, I prefer to ride my bike, not rebuild it every other ride.

Next.
Posted: March 20th, 2008, 6:46 pm
by fastkart
Wiseco, all the way. Never seized one or had any trouble that was piston related while running one.
Posted: March 20th, 2008, 7:27 pm
by AlisoBob
I want :
"0" time FACTORY ASSEMBLED Stock CR500 Bottom end with a Eric Gorr " Mo Betta'" jug. The only changes would be 2x sealing area on the base gasket at the transfer ports.
Period.
You can keep all your aftermarket junk...
Posted: March 20th, 2008, 7:39 pm
by Xylicon
I like my Wisecos, never had a problem,

Posted: March 20th, 2008, 7:47 pm
by pstoffers
Posted: March 20th, 2008, 8:07 pm
by 100hp honda
heres the run down so far:
wiseco
1- 100hp honda
2- fastkart
3- xylicon
4- Pstofers
finally saw the light and converted to wiseco
1- brit
2- danny graves
3- MFDB
cast PRO-X
1- aliso bob
2- ported&polished

Posted: March 20th, 2008, 8:16 pm
by ou812
I'm still not sure, I've always been for cast ,but on my latest I've gone wiesco at 32, bored with a plate, need more time on it but all is good so far but it's still smoken rich, ain't had time to jet yet. Time will tell.
Posted: March 20th, 2008, 8:35 pm
by dannygraves
hey man, I've always run wiseco all the way mang!!! seized my fair share..

but, hell, I used to run wisecos in my CAR!

Posted: March 20th, 2008, 8:36 pm
by bigjay
i just want my next piston to not do this EVER
thats my only wiseco experience except for the one that was in my yamahaha 490 back in high school which had about a million hours on it and still ran strong. what are the what pro's and con's to each type?
Posted: March 20th, 2008, 8:41 pm
by dannygraves
you can run tighter tolerances in a cast because they expand less than the forged, forged are stronger.
If you want an all stock bike and want to be able to fire it up cold and hop on wihtout hearing any piston slap, then cast is the way to go. If you want to build a hot rod bike and pay close attention to your tuning and temps, forged is the way to go.
hill climb or dunes riding, I would think %100 forged. Trail, MX, cast
Posted: March 20th, 2008, 9:10 pm
by bigjay
are wiseco's forged and pro-x cast?
Posted: March 20th, 2008, 10:06 pm
by fastkart
bigjay wrote:are wiseco's forged and pro-x cast?
Correct.
Posted: March 20th, 2008, 10:17 pm
by Ported&Polished
bigjay wrote:i just want my next piston to not do this EVER
I could be wrong, but that looks like a Wiseco to me. A stock piston will crack, but a forged unit will blow up and destroy your motor, oh, I see you already found that out.

Posted: March 20th, 2008, 10:25 pm
by britincali
Now lets see the first rebuild I did personally was a 1987 YZ490 and in that motor I used a ........
wiseco!
I have always been a fan of forged, the only time Ive installed a cast piston is when I rebuilt the bone stock 87 motor in the AF.
Posted: March 20th, 2008, 10:39 pm
by iggys-amsoil
I still marvel at that picture Jay. The only dif b/t mine and that is mine was a stock cast and it has a crack 3/4 across the top of the crown.
Used Wiseco for years and some @ 100:1 mix in the 250 3 wheeler.
Posted: March 20th, 2008, 11:14 pm
by TYSTYX
100hp honda wrote:heres the run down so far:
wiseco
1- 100hp honda
2- fastkart
3- xylicon
4- Pstofers
finally saw the light and converted to wiseco
1- brit
2- danny graves
3- MFDB
cast PRO-X
1- aliso bob
2- ported&polished

Add me to the cast list

Posted: March 21st, 2008, 6:39 am
by MICK
I can easily go either way. Used nothing but OEM pistons in my KX500. Growing up I was also under the impression Wiseco pistons were junk, just a cheaper option to an OEM piece. My AF is the first bike I've used a Wiseco in. And to this point I am very pleased with it, it seems my feelings towards them couldn't be further from the truth. Honda puts their cast piston in that sleeve with .07 clearance. I put the Wiseco in with .03 as per instructions. Less than half the clearance of the stock cast piston!
I don't think it matters as much what kind of piston you use, cast or forged, as much as it does how well you're sleeve has been machined to accept that piston. 100% of failures I've seen were operator error or a sorry ass bore job.
If I had to choose one or the other the lighter forged Wiseco would get my vote.
Posted: March 21st, 2008, 7:15 am
by AlisoBob
MICK wrote: Honda puts their cast piston in that sleeve with .07 clearance.
"Ah..... Thats a big negative Ghostrider..."
Thats .07
MM.....
or 0.0025"
NO piston is running 1/2 that...
Cast makes more power too, by the way.

Posted: March 21st, 2008, 7:22 am
by pstoffers
Posted: March 21st, 2008, 7:46 am
by MICK
AlisoBob wrote:
Thats .07MM.....
What the hell did you think I was talking about?? .07 yards? I say again Honda's original clearance is .07 or .0027 whichever unit of measurement you prefer.
Bob you're a goofy old fart. I am interested how a cast piece makes more power though.
I'm listening
EDIT: Holly shit I just realized something that you said Bob. Wiseco's recommends .03 in. Yes I doubt any piston can operate with less than that. I stand corrected.
And I have a feeling you're going to say a cast piston makes more power because you can run them snugger in the bore. But a forged piston is so much lighter I think it about evens those gains.
Posted: March 21st, 2008, 8:07 am
by dannygraves
hes probably going to say that because of tighter clearance, there is less blowby and less power loss to piston rock. Last time I had my wiseco out it showed 0 signs of blowby and is still a bear to kick. If a cast piston does make more power it is marginal at best, I prefer the insurance of a stronger piston myself..
Posted: March 21st, 2008, 8:21 am
by AlisoBob
dannygraves wrote:hes probably going to say that because of tighter clearance, there is less blowby and less power loss to piston rock.
Bingo Danny.... good work.
Dont forget heat reflection ( cast doesnt conduct heat as well). Forged grow in EVERY direction. This means the wrist pin hole and ring lands grow too. The cylinder walls of forged piston motor look pretty thrashed for the most part. Cast piston motors are silky smooth...
This is my bike, 3 year old bore
http://www.bannedcr500riders.com/board/ ... php?t=1629
You want the rings as square in the bore, and as tightly sealed to the piston and cylinder as possible. Cast is the hands down winner in this regard.
Posted: March 21st, 2008, 8:24 am
by dannygraves
it all comes down to application, if I had a bone stock bike that I only hit the trails or track on, it would run a cast piston fo sho, but since I hit the dunes... its forged for me all the way!
Posted: March 21st, 2008, 8:34 am
by AlisoBob
Why make an exception for the dunes?
N20 Yes
Land Speed Record Attempt Yes
CH3NO2 Hell Yes!
Otherwise, Cast is fine.