tomseal6
VIP Member
gentleman on ebay is offering a SNOWMOBILE PISTON KIT YAMAHA SRX 700 BALANCED PRO MOLY on ebay a states that there are BETTER THAN STOCK, AND BETTER THAN A FORGED WISECO PISTON. i have heard nothing else than stock is better from everybody on this site. what are your opinions?
http://cgi.ebay.com/SNOWMOBILE-PIST...209338840QQcategoryZ26356QQrdZ1QQcmdZViewItem
http://cgi.ebay.com/SNOWMOBILE-PIST...209338840QQcategoryZ26356QQrdZ1QQcmdZViewItem
mulderdad
New member
Bump.
lol
I was just going to post this exact question about these pistons.
Looks like a good deal if they are better than stock.
lol
I was just going to post this exact question about these pistons.
Looks like a good deal if they are better than stock.
srx dreamer
New member
Kind of weird if i read his writing it says u will get 2,000 miles or more how could they be better then stock if u got 2,000 miles out of them? In the automotive world cast pistons suck and forged is the way to go like if u want to run nos cast pistons would melt froged can take the heat way better, I dont see how a cast piston can be better then forged ,and on top of that wiesco has been around forever and if anyone knows how to make a quality piston I would say it would be them.These pistons are nameless! Just my 2 cents
sxviper32
New member
wow, i just saw those on ebay and came here to ask....
Mysledblows
VIP Member
They look like SPI's to me.
vipertripplexxx
New member
YEA, OK, SURE, They go through the extra process of forging because it's fun, and costs less to do more work!!!!! Stick with a proven products, pinchin pennnys is'nt usually wise.
Maddogs700srx
VIP Member
I have been told that the SPI's are pretty decent replacement pistons.
mrviper700
VIP Lifetime Member
ok, went and read the ad, flaking rings??? never have seen 1 case of flaking rings in a yamaha,.....EVER!!!
You cant out do the powder forged pistons in a srx/viper, they are state of the art process and unmatchable strength. The key to any piston being better then a wiseco(which this guy compares to) is that with a cast piston, they dont expand as rapidly and can be run to a tighter tolerance to bore clearance, the tighter the piston fits in the bore, the less it rocks back and forth, and you get better ring seal from that trait.
Piston ring seal is cruicial in a 2 stroke engine, the piston basicly is your valves and camshaft of that of a 4 stroke engine, generally speaking of course.
Back to a yamaha piston, they yield the strength of a forged piston yet dont expand rapidly like a hammer forged unit(wiseco) does, they are every bit as strong, run thick rings, which means long service life. Wiseco has thinner rings, better for power output(less drag on the cylinder walls) but shorter life will result.
the coatings applied to the guys pistons are a great thing, these have nothing but benefits from them. These can be added to any yamaha piston as well.
I would be curious as to the weight of the piston and manufacturing tolerances. Its gonna be awfull tough to pass up a yamaha powder forged unit, they simply last forever and offer superior strength over a cast unit.
You cant out do the powder forged pistons in a srx/viper, they are state of the art process and unmatchable strength. The key to any piston being better then a wiseco(which this guy compares to) is that with a cast piston, they dont expand as rapidly and can be run to a tighter tolerance to bore clearance, the tighter the piston fits in the bore, the less it rocks back and forth, and you get better ring seal from that trait.
Piston ring seal is cruicial in a 2 stroke engine, the piston basicly is your valves and camshaft of that of a 4 stroke engine, generally speaking of course.
Back to a yamaha piston, they yield the strength of a forged piston yet dont expand rapidly like a hammer forged unit(wiseco) does, they are every bit as strong, run thick rings, which means long service life. Wiseco has thinner rings, better for power output(less drag on the cylinder walls) but shorter life will result.
the coatings applied to the guys pistons are a great thing, these have nothing but benefits from them. These can be added to any yamaha piston as well.
I would be curious as to the weight of the piston and manufacturing tolerances. Its gonna be awfull tough to pass up a yamaha powder forged unit, they simply last forever and offer superior strength over a cast unit.
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ModMMax
New member
Lots of ways to improve a Yamaha engine. Changing to aftermarket pistons is not one of them.
tomseal6
VIP Member
yea thats what i thought. thanks everybody. i knew that guy didnt know exactly what he is talking about. but somebody will believe him and buy them
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YAMMIENEWBY
New member
The company that makes these pistons makes pistons for cudney racing,
spi is just the buyers group, or distributor. I believe some guys on here run these and have had good luck with them, the price sure is right.
spi is just the buyers group, or distributor. I believe some guys on here run these and have had good luck with them, the price sure is right.
mrviper700
VIP Lifetime Member
gary, you dont need new pistons for the 700, just install new rings, yours are fine, I looked at them when I removed them.
YAMMIENEWBY
New member
Thanks Don,
I was looking at them thinking while it was apart I would replace them,
but think I am going to just re-ring the stock ones,I can get them for 129.00
for all 3 and a set of rings and cages is going to cost me 100.00 so I may order them and keep them as a spare, I am interested in the weight of them also.
I was looking at them thinking while it was apart I would replace them,
but think I am going to just re-ring the stock ones,I can get them for 129.00
for all 3 and a set of rings and cages is going to cost me 100.00 so I may order them and keep them as a spare, I am interested in the weight of them also.
mrviper700
VIP Lifetime Member
the only other thing I have to add is if they are only $129 for all 3 what kind of quality are they really gonna be?? remember you ALWAYS get what you pay for in the end. I would be leary just from the price, thats just my opinion, doesnt mean its right.
tomseal6
VIP Member
don you busy this spring?
mrviper700
VIP Lifetime Member
I am always busy Tom......LOL
just call me when your ready....................
just call me when your ready....................
tomseal6
VIP Member
ok will do that. looks like im gettin another smokin deal. hopefully ill have better luck with this top end
YAMMIENEWBY
New member
Don, yeah I would agree, very cheap. Cudney had nothing but good things to say about the pistons they make for him, but if it seems to good to be true, it probably is.......I'd be interested in seeing what you think about em when I get them, I'll send pics.
maxdlx
VIP Lifetime Member
I just bought a set of these pistons. I asked the guy why so cheap when the same set in JR Grahm is 50 bucks higher. He said he is doing it to promote them. I might send one to Don and let him see what he thinks. maxdlx