Can this pipe be put on a 701 motor? If not im guessing that the 701 will have to use the factory pipe. This is going on a 91 square nose. thanks
Coffman 650 SJ pipe
- Thread starter Rheeder218
- Start date
wayne
wannaroll
- Location
- Mesquite, Texas
you can use it, you will need to port the manifold to match the 61x cylinder.
Mouthfulloflake
ISJWTA member #2
- Location
- NW Arkansas
it works well actually with the 61x engine...
cool
alright my next question is what can a 650 be bored out to?
Is it a good idea to bore out a 650 to a 701 or something like that?
Thanks for the help, not familiar with yamis. This a project im doing for my brother.
alright my next question is what can a 650 be bored out to?
Is it a good idea to bore out a 650 to a 701 or something like that?
Thanks for the help, not familiar with yamis. This a project im doing for my brother.
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Mouthfulloflake
ISJWTA member #2
- Location
- NW Arkansas
Not worth the $$$ to bore it out on the 650 cases.
it IS worth it to port the 650 cylinder though, take a $20 dremel, and widen the exhuast port, and you can even raise it a mm or two.
also, the 61x cases are a DECENT upgrade IF you can get them and the reeds, pretty cheap ( like $50-$75)
it IS worth it to port the 650 cylinder though, take a $20 dremel, and widen the exhuast port, and you can even raise it a mm or two.
also, the 61x cases are a DECENT upgrade IF you can get them and the reeds, pretty cheap ( like $50-$75)
gorilla
There's Always A Light At The End Of The Tunnel !!
- Location
- Lost Wages NV
you can bore to i think to 81.50mm but that's as far as you would want to go.
the cases might have to be mod'd for the bigger pistons, but that's just a little grinding on the top case surface's.
most jetskier's just get a 62t motor and be done with it.
you could also get a msd cdi and prop now that you have a pipe.
check out the ski's - superjet section.
a lot of good info there too !!!
good luck
gorilla
the cases might have to be mod'd for the bigger pistons, but that's just a little grinding on the top case surface's.
most jetskier's just get a 62t motor and be done with it.
you could also get a msd cdi and prop now that you have a pipe.
check out the ski's - superjet section.
a lot of good info there too !!!
good luck
gorilla
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isnt the 62t 760 motor? If i could find either a 61x or 62t that would be great. I would go that route as well.
Does anyone have a picture of where and how much would need to be ground off?
Does anyone have a picture of where and how much would need to be ground off?
Mouthfulloflake
ISJWTA member #2
- Location
- NW Arkansas
lay a 701 gasket over it, drop some bolts thru to line up the holes, mark it with a sharpy and grind away.
you basically grind away where I marked in red, to match the gasket.
its easy.
62t is the dual carb cases that the superjets after 1996 came with, 701 with dual carb case.
you basically grind away where I marked in red, to match the gasket.
its easy.
62t is the dual carb cases that the superjets after 1996 came with, 701 with dual carb case.
Attachments
Thanks for that, help that was my plan. But i am looking for how to do the cases.
can the coffmans fit on a 62t motor as well?
and if im not mistaken the electronics from a 6m6 motor and go into a 62t right?
and if im not mistaken the electronics from a 6m6 motor and go into a 62t right?
Mouthfulloflake
ISJWTA member #2
- Location
- NW Arkansas
use a sanding drum and enlarge the openeings in the case where the cylinder protrudes into the cases.
the ones I have that have been machined, dont have a LOT removed, it would take a little while, but easily doable by hand.
electronics will fit into any case, as long as you use the flywheel that goes with the electronics.
the ones I have that have been machined, dont have a LOT removed, it would take a little while, but easily doable by hand.
electronics will fit into any case, as long as you use the flywheel that goes with the electronics.
cool thanks for the help
I think were going to go to the route of rebuilding the 650 and doing everything to it port, plate and full bore. should be a decent motor
Mouthfulloflake
ISJWTA member #2
- Location
- NW Arkansas
honestly, I wouldnt spend the money for pistons/bore on a 650.
there are a couple of 701 engines for sale here for slightly more than rebuilding the 650 will cost you...
there are a couple of 701 engines for sale here for slightly more than rebuilding the 650 will cost you...
Well he doesnt want to buy anything that he doesnt know whats in it. I said you sould just buy a 701 for the same price but i got that response.
Is it a bad thing to do this to 650 cases and cylinders
did someone make a dual intake for the 6m6 cases?
ye i'm kind of in the same boat here ive got a 90 and a 93 SN SJ of which the 90 im fixin up for myself and was wondering about some of these same things ... these ski's dont have much use and fire up and run well every time ... i hate to drop in a whole new motor ... just for a little bit more bore etc.
Mouthfulloflake
ISJWTA member #2
- Location
- NW Arkansas
stock vs stock, yes.
but a 650 with lots of compression, some basic port cleanup and a pipe.
will be as strong as a stock 701 with a pipe. well VERY nearly as strong.
I just made that exact swap.
Now im having to ad compression to the 701, and get it more dialed in to get any improvment over the old 650.
its not a HUGE difference to me.
jump to 62t cases, andyou would likely have a huge difference, 650 to 61x? not so much to me.
just my experience here recently.
but a 650 with lots of compression, some basic port cleanup and a pipe.
will be as strong as a stock 701 with a pipe. well VERY nearly as strong.
I just made that exact swap.
Now im having to ad compression to the 701, and get it more dialed in to get any improvment over the old 650.
its not a HUGE difference to me.
jump to 62t cases, andyou would likely have a huge difference, 650 to 61x? not so much to me.
just my experience here recently.