just thought of this but hey its probably been thought of or asked before. you might thinkthis is dumb but will 3 94-96 v-max cylinders work on a sx 700 triple bottom end to make a cheap 900 big bore providing stock sx heads work or may have to be modified?
800
New member
caravanman
New member
So it three 500 cylinders and a SX,SXR or Viper lower end?????
800
New member
No it's 2 500 cases and heads put together, SX or SRX cases are not wide enough
caravanman
New member
That sound like alot of cutting/welding/TIME for the case and head and $$$$ for a custom crank!
This must have been done 96/97 i'm guessing?? Sled is a 94 with Vmax 4 skis and XT adjustable TSS.
This must have been done 96/97 i'm guessing?? Sled is a 94 with Vmax 4 skis and XT adjustable TSS.
800
New member
That was done in 95, doing the cases and the head really didn't take that long, the only bitch was the crank, we had to make the 2 center pieces with the splines because Yammie was nice enough to use 13 splines which you couldn't turn 120 degrees, other than that the crank is all stock pieces. Crank balance was an issue, but we had to do that twice and I added a fluidamper just for good measure. It had the adjustable struts from an Exciter SX, but it handled better with the GYT adjustable valving struts so thats whats on it now. That sled has been trail ridden like that for 2800 mi. Whats nice about taking the time to make the bottom end is you can make the motor just about any size you want then.
800 said:
posted pics above is a tripple. im confused. wouldnt 2 500 cases make a 4 cylinder top end? whyn wont the 600 twin cylinders fit on a SX case. i cant imagine them being that much bigger than than 232 cc where the 600 twin cylinder is only slightly less than 300cc a piece.
800
New member
yes the pictured sled is 2 twins cut up and made into a triple, think about it, you use 1 1/2 of each. The physical size of the twin cyls is no way gonna fit on a SX case as well as bolt patterns and the height of the cyls. The twin has a much longer stroke as well as a way longer rod.
who's sled is that??? where is it at??? im surprised they didnt try to do it with 600 cylinders and cases to make it a 900. sticker discplacement decals would have been cheap to replace 
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vipertripplexxx
New member
give us the skinny
So what did that thing run? Sweet pipes!
So what did that thing run? Sweet pipes!
800
New member
That sled is my 94 500. When I originally put it together it was a 750 thats why the decal, it is a 900 now, I first made it a 750 because that is a square motor, I then later put the 600 cyls on it, as a 750 its best was 119 and as a 900 it ran 126.7 on really good conditions but commonly in the low 120's, it's just another example of me being bored or having too much time on my hands back then, that is with stock jugs and carbs, I made it as a trail sled, thats why it has an airbox and oil injection. I had to do it because they gave you all that extra room in those sleds. You should see my triple 800 Kawasaki, Exciter, that was from 89', the pipes were a bitch in that thing.
how much you charge to make me a 900 motor??
Junior
New member
there's alot of other ways to make a 900 motor, and displacement doesn't necessarily mean power.
discplacment means all the power in the world to me if you know how to utilize the potential of the motor's efficiency,
Junior
New member
tomseal6 said:
you might find it tough getting all that great a crankcase compression ratio or scavenge ratio out of a 500 bottom end.
besides, piston surface area is actually lower on that 900 than it is on a stock SRX or viper.
keep raising the ports and modify the head accordingly.
Junior
New member
tomseal6 said:
look man, I don't wanna argue with you on this, but I'll just say it's not the most effective, or the cheapest way to make a 900
hey man i never said it was the best or cheapest way. i didnt know my interest in 800's cool sled that he made would bother you
800
New member
Tom, thanks, it is a cool sled and I've had lots of fun with it as well as made lots of bar racing money with it, kinda funny, "you want to race my 925 Mach Z with that 500?" should have been there for that one.
Junior, since you brought it up, what is the relative crankcase ratio of the early twin bottom end compared to and SRX, you made the statement, therefore you must have checked both, as well as, the piston surface area between a 74.5mm piston and a 69mm piston with the same dome arc, the larger piston has less surface area? The 74.5 piston would have to flat for that to be true, or the dome on the 69mm piston would have to be 2mm higher than it is, and it isn't.
And if I was gonna make an SRX a 900 what would I do? Stroke it to 68mm, like everybodys doing, and bore it to 74mm, Hmmm, this motor already comes that way and it is wider, providing larger transfer port areas which is what you really need to fill the larger bore cylinder and make more power. This is what te SRX cases lack.
Anyway, who cares, I built it, it's a cool sled, and it looks like it came that way. Maybe thats why it was in the Yamaha booth at the snow show in 96', (note the pic)they thought it was a nice piece too.
Junior, since you brought it up, what is the relative crankcase ratio of the early twin bottom end compared to and SRX, you made the statement, therefore you must have checked both, as well as, the piston surface area between a 74.5mm piston and a 69mm piston with the same dome arc, the larger piston has less surface area? The 74.5 piston would have to flat for that to be true, or the dome on the 69mm piston would have to be 2mm higher than it is, and it isn't.
And if I was gonna make an SRX a 900 what would I do? Stroke it to 68mm, like everybodys doing, and bore it to 74mm, Hmmm, this motor already comes that way and it is wider, providing larger transfer port areas which is what you really need to fill the larger bore cylinder and make more power. This is what te SRX cases lack.
Anyway, who cares, I built it, it's a cool sled, and it looks like it came that way. Maybe thats why it was in the Yamaha booth at the snow show in 96', (note the pic)they thought it was a nice piece too.
Junior
New member
800 said:
sorry man, I didn't realize it was yours. and the info I have for the 500 was showing a 68mm square cylinder.
no, never measured them both, going by looking at it, the SRX case was designed with CFD software, but then again, when you built that the SRX was just a glimmer in some engineers eye.
just did some reading, I was thinking of the 97+ 500 motor, not the 96 and back one.