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Discussion Starter · #1 ·
first off awesome site, lots of good info glad I joined up. anyway as the title says I have picked up a 680 triple out of a 96' Polaris ultra rmk for an engine swap into a quad project (going into a scrambler for dunes, mud, high speed stuff, going to be widening the front and stretching the back too) and i've got most of the details sorted out, and I've got some questions on a few parts and I'm hoping someone can help me out.

the first one is the cdi box. is there anyway to test these to see if they functioning properly (I want to make sure it's in good shape so it runs in tip top shape), and if by chance it's bad, or goes bad on me, are there relatively inexpensive replacements available (dealer wants 450 for one), perhaps an aftermarket one or something from another quad that would work? Also does anyone know of where/ have a wiring diagram for one of these units?
next would be the coils, pretty much the same as above, just trying to keep costs down as much as possible, but I'll pay if I have to.

next involves the carbs, anyone have any recomendations on a full replacement carb setup that would benefit he motor and not break the bank?

lastly would be the belt, does anyone know of the longest available cvt belt, or are they pretty well all the same length?

thanks for an help
 

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Your putting a two stroke 680cc triple cylinder Ultra 680 motor into a 500 Polaris Scrambler chassis? What are you doing with the pipe? jetting? cooling? carbs? I dont see how this will fit without serious modifications to the frame?
 

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It's been done before I've seen one with a liberty 800 twin with the 4 wheel drive still working and then I've seen stretched out hill shooters i'm on my phone now I'll get pictures later
 

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Discussion Starter · #4 ·
Yeah its actually pretty easy, frame is a non issue, lots of room, and if it was in the way its easy to fab it around the motor, that said the motor has a motor mount plate (best way to describe it) to mount it at the right angle and allows it to be easily mounted. The pipe is just a single, that will involve some cutting and turning, but it'll fit, its close as it sits right now (it'd be nice to pipe it but i'll hold off on that for now, unless someone can recomend a single pipe for this motor). the quad is liquid cooled as it sits so just a matter of hooking the lines up (rad is up and out of the way) and since the scrammys are cvt there's no custom work there, just line up the clutches, respring them and hopefully it'll be good to go. The motor will be a tight fit and is the reason i ask about the long cvt belt as it would let me move the motor further ahead so it gets the weight up front to keep the nose on the ground and gives me more foot room too. http://www.youtube.com/watch?v=3G8iUNjWoCg

So yeah dd some searching and it seems that i should be able to use a different CDI, but what would be the best one to use? Also found that it'd be fairly hard to determine the state of the cdi, so i think i'll just swap out for a new one, I'll use whatever coils match the cdi for best results.
 

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Running a single pipe on a triple motor, will cripple the motor for horsepower by about 25%...
 

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Discussion Starter · #6 ·
factory is a single pipe on this motor, pictures of the project: http://forums.atvconnection.com/polaris/328238-700-scrammy-project.html, I know that power wise a single is not the way to go, but remember the application, and the fact I have limited room
on where to run the pipes limits me as well.
 

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single pipe in an atv will still be insane fun!

nothing wrong with the round slides, you can look for used rack setup from an xcr but then you have to make sure you put on black slides. you will have 500 bucks into the carbs.

no need to go long on the belt, a storm belt is about the longest belt that will work, i hope you are getting rid of the atv transmission and running a simple jackshaft with the sled secondary. by far a better setup than the atv transmission. been there done that.

air filtering, make sure you some up with some good filters, you can run a single air filter like from a car and then make a good sealed airbox that clamps to the carbs so you dont dust the engine.

you will need the electric fan from a small car to help keep the engine cool, and possibly a bigger radiator depending on if you are going to try to get miles on or just race. you will need to get the key, and rectifier from an electric start sled and regulator from the snowmobile so you can run a battery.
 

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Discussion Starter · #8 ·
thanks for the info :D. I'll be using the quad tranny, I bought the scrammy for 4wd and its staying put so the tranny is a must, but what i could do pending on how thing work out is swap the sled secondary in place of the quad secondary, we'll see, this is also why I was curious about the longer belts as i would like to keep the tranny in place and inch the motor ahead just a little bit to gain some room.

rad should be good, it already has a fan, but i may need to build a shroud for it, since theres three carbs i'll run a single filter and run it up high, not that difficult and it'll help save on room, for the carbs i'll leave them as is unless i have issues.

Lastly (forgive the newbishness lol) but what are you refering to when you mention rounds slides and a used rack off of a XCR? I'll be taking the plastics off the quad tomorrow to start measuring things up.
 

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round-slide Mikuni carburetors and rack-style Mikuni carburetors
 

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Discussion Starter · #10 ·
Gottca on the carbs, thanks.

Did some searching, would a cdi & coils and such from a late 90's early 2000's 700/800 xcr work?
 

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Coils- Yes.
CDI box- no.
CDI has to be from a 1996 or 1997 680 Ultra motor (Excluding the '97 Ultra SPX motor)
 

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all of the ignition parts from any fugi triple will bolt on, you just have to match cdi to stator if you start replacing parts. all coils are the same so get the cheapest ones you can if you need one.

i would pay for the xcr 800 cdi and stator, they usually bring a pretty penny since they are so easily programable.

i also would pay for the flat slides, i believe in your situation the round slides will work better for clamping an air box or hose to the carb.

if you have to run the tranny then you have to play with engine tilt and hieght to make sure you can get close enough to run a belt but still get the carbs to clear the tranny. without a doubt figure out how to get rid of the atv secondary, it is a performance killer compared to a sled secondary.

since the 4wd is chain driven i would make a jack shaft that simple runs the rear chain and front chain. get rid of that polaris transmission, its a lot of weight and a pain to build around.
 

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Discussion Starter · #14 ·
front is shaft drive, plus the reverse is something I'm not about to get rid of. the gearbox on the scrammy's are pretty stout, and from what's being said I'll do my best to change out the secondary to a sled unit on the quad gear box. thanks forthe carb advice, I'm thinking the biggest clearence issue is going to be the seat and body work on whether the carbs will fit, but a single air box and some creatative plumbing/fab work it should sneak in there nicely. So with the cdi, providing the stator is changed (which wouldn't be a bad idea to do) I can use it? that will make things a little better on getting parts thanks.
 

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if the stator is bad you can have it fixed or change it but if the sled has spark there is no need to change ignition stuff.

you can mount the air box in the rear under the seat then run hoses up to each carb. chances are there will be very little room between the engine and gear box.

didnt know that one had the shaft drive for the front.

I guess what i would do it make a peice of steel that you can bolt to the end of the crank and to the shaft for the secondary that is 12.5" from center to center. that way as you lift or lower the engine or tip it forward/backwards the plate will keep the center distance the same so you dont have to worry about remeasuring each time?

the other thing i have seen is that guys either stretch the chassis way out so there feet are in front of the engine or stretch it out the back and put the engine behind the tranny.
 

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Discussion Starter · #16 ·
engine was having spark issues and is why I was able to get the unit as cheaply as I did, I'll be taking the plastics off tonight, and I'll grab a few pictures to show what I'm working with.
 

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mustange70 said:
Yeah its actually pretty easy, frame is a non issue, lots of room, and if it was in the way its easy to fab it around the motor, that said the motor has a motor mount plate (best way to describe it) to mount it at the right angle and allows it to be easily mounted. The pipe is just a single, that will involve some cutting and turning, but it'll fit, its close as it sits right now (it'd be nice to pipe it but i'll hold off on that for now, unless someone can recomend a single pipe for this motor). the quad is liquid cooled as it sits so just a matter of hooking the lines up (rad is up and out of the way) and since the scrammys are cvt there's no custom work there, just line up the clutches, respring them and hopefully it'll be good to go. The motor will be a tight fit and is the reason i ask about the long cvt belt as it would let me move the motor further ahead so it gets the weight up front to keep the nose on the ground and gives me more foot room too. http://www.youtube.com/watch?v=3G8iUNjWoCg

So yeah dd some searching and it seems that i should be able to use a different CDI, but what would be the best one to use? Also found that it'd be fairly hard to determine the state of the cdi, so i think i'll just swap out for a new one, I'll use whatever coils match the cdi for best results.
thats frigging cool!
 

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Discussion Starter · #18 ·
new pictures are up: http://forums.atvconnection.com/polaris/328238-700-scrammy-project-2.html. I'm going to hit up the polaris dealer and see about a longer belt, as if i can move it foward a few inches i will free up a lot of room as in stock location its a pretty tight fit, and also looking at the scrammy's tranny i can't move it because the sprocket is at the swing arm pivot point. carbs will be easy to get in there, as the carb is on the top of the tranny, and the carbs are layed flat on the 400, the 680 ones are pointed at an upward angle. (the pictures in that thread show this). check back for updates tomorrow.
 

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here is one i have a few more that are tripples id youd like me to upload them
20107280013468_22144.jpg
 

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i cant find the one still using the 4 wheel drive but here are a few hillshooters
2010728211448703_22144.jpg
201072821145193_22144.jpg
2010728211453125_22144.jpg
2010728211454968_22144.jpg
2010728211456750_22144.jpg
201072821150234_22144.jpg
 
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