81 SRX 440 pipes interchangeable??

SRX540

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Nov 16, 2010
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Ontario, Canada
A friend that is pretty knowledgeable was telling me that the 81 srx are interchangable with the 81 s440 pistons but yamaha sites are showing me 2 rings as aposed to the one ring srx piston. I know the 80 ss440 yamaha has the same igition as the 81 srx. These 81 srx pistons are hard to find and expensive any insight would be great.
 

Your thread title doesnt match your question. Title says " Pipes " the questions says "pistons"
 
Never compared the two but I would think there would be issues.

SS is a reed valve steel bore engine. SRX is chrome and piston port.

???????????????

opsled
 
I WOULD HAVE TO GO BACK TO MY OLD SERVICE MANUALS TO BE SURE. I KNOW THEY WERE BOTH 437 cc, BUT LIKE PHIL POSTED, CHROME BORE VS STEEL CYLS, THAT RIGHT THERE WOULD MAKE FOR RING TROUBLE. ANOTHER FACTOR IS DUAL RING VS SINGLE AND HUGE EXHAUST PORT OPENING ON 81 SRX. WITH THIS SAID, I BELIEVE PISTONS WERE THE SAME SIZE, BUT WON,T INTERCHANGE. 3:16 (yammie tony)
 
Pistons

I was thinking the same thing, the 81 ss 440 piston kits are $140 a piece anyway i thought they would be cheap...My Dad also said something about the rings/port issue and if you(Tony) and opsled dont know if another piston would work then they probably wouldnt.... Ebay was showing me pistons that were one ring for the ss 440 but again chrome bore/steel bore= not interchangable.
 
WIESCO NEVER MADE REPLACEMENT FOR THE 81 SRX. SURE THEY DID FOR 81 SS 440. I REMEMBER PARTS UNLIMITED (made in tawain ) HAD REPLACEMENT, BUT THEY WERE JUNK. I ONLY USED OEM IN MY 81. 3:16 (yammie tony)
 
Pistons

My friend is no shoemaker he's an engineer and really knows his vintage stuff hes saying the pistons are the same and that the rings wont catch I have aftermarket pistons but scared they will grenade my nice motor.....
 
DON,T KNOW MAN. I THOUGHT YOU CAN,T USE RINGS THAT GO IN A CHROME BORE CYL IN A STEEL BORE MOTOR. LIKE I SAID, I WAS NOT SURE. 3:16 (yammie tony)
 
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I asked a Kimpex rep. if their piston rings were for the steel sleeved or original chrome bore and he explained they would work in either ? Part# R09-9023
 
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hahahhaha

Until the skirt snaps off and grenades your motor in the first ten minutes of the ride they would work ya lol.
 
They will not interchange . The SS 440 had a 18 mm wrist pin diamater and the 81 SRX had a 20 mm diameter. If I remember correctly they were also in a different location on the piston.
 


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