Comet Drive to Polaris Driven and Tranny.

[CTE007]

Hello all!
Some project info.- A American Sports Work UTV ( honda gx390 motor) that got tattoo'ed in the butt by a car. Bought it at a yard sell for 150 bucks. The rear transaxle was shattered into two down the middle of the tranny. They only sell it as a complete unit for 1200 or 1800 bucks. Not Happening!!
While consuming carbonated beverages in the garage, one of my buddies mentioned he had a junker polaris that had a tranny and driven clutch on it. Forty bucks later it ended up at my garage. So to my dismae, internet searches begin.... Not really much about the topic . They either stated a Comet drive to Polaris driven will NOT work or you have to change to a Polaris drive to match the driven. I never actually came across a build- kart, utv, or mini buggy that tried it ..Why want it work? Anyone? What are the problems that cause it not to work?
Not being able to find a posted internet failure. I gambled, worse case i'd be buying a polaris drive and doing the mod to crank to run it. So plasma cutter, welder,many carbonated drinks and 2 weeks later. I got hangers/36 inch axle, hubs, spocket holder, removed the transmision mount with tranny from four wheeler.
Unlike others that use a polaris tranny on custom/home builds i mounted it behind the motor, to keep the original engine location. Everything is all fab up, it needs a few tweeks and things made permenent. Rear wheels raised up off the ground both drive and driven clutches work in harmony..... on the ground at idle i dont have any clutch crawl. I Do not have the tranny brake on, it was already gone. I also dont have a brake on my solid axle. To test it further in pure texan style i chained it to my tractor and nailed it in High gear. It bit in good and performed like a champ. didnt notice any belt slippage. Killed it and put the tranny in Low. It bit in even better. However i didnt notice that the chain to the tractor popped off so it tried to crawl up a 8 foot metal privacy fence.. Am I missing something? I just expected this thing to putt around and the belt to slip alot..Time to go brake shopping? Anyone have any suggestions for stopage equipment?
Guess further testing once i have some brakes, it will give me more answers. I think of a Utv as a slow,big,cushiony suspensioned gokart that will not spill my drinks. I wasnt expectioning dirt slinging, and fence climbing.
So to the point- why is this set up not suppose to work? Anyone done or know how to fab up the cable shift lever on a Polaris tranny? What is a reasonably price brake to use on a 1 inch axle on a heavier build?
Addition project info: American sports works utv-motor honda gx390-tranny out of polaris 4 wheel drive- Back wheels off the polaris 26x10x8 i believe- Drive spocket- stole the one from the polaris and put in on a 1 inch axle hub. Its has a fewer amount of teeth than i usually see on a industrial motor powered vechicle. Im using the original polaris belt.
This setup has been pleasantly surprising, not at all the outcome that i was expecting...
Thoughts suggestions plz?

 

[KartFab]

what type of comet drive is it? 40 series? duster?

You can rig it to 'work', but it will not perform well.

For starters, the belt top width may be mismatched (7/8" vs a 1 3/16+) So the drive unit may be fully engaged, but the driven only half engaged at max rpm...so you dont get the speed.... Or the drive engages and "peels out", and the driven stays in the low gear because the drive cant pull the belt up any higher. We need more information about your drive and driven.

 

[CTE007]

I will have to do more research on the Drive unit. The new models of the UTV use Cvtech. Mine is probably 5yrs plus old, it was wrecked then stayed parked. Dont even know if comet was still around then....I did have the original belts that went to the UTV and ATV. The belt widths were not the same but maybe 1/16 or 1/8 inch difference, if i remember correctly. The major difference was length. I used the longer atv belt. When the vechicle is jackup. When the drive is fully closed, the driven is fully open. From that perspective they seem to be in harmony... I undestand underweight things might be different, and I have no experience with cvt's... AT this point in the build it looks promising from a utv perspective. I guess i was just expecting it to be a total fail. It pulled surprisingly good. Jacked up and in high gear, im thinking that thing would be moving around 30-35mph. Plenty for a UTV. I had a video that I was going to post, then the Utv got into a arguement with a fence. No blooper's allowed! Was funny though.

 

[CTE007]

I googled both looks more like a comet 40

 

[landuse]

Post some pics

 

[CTE007]

I'll take some today, heading out there to see if I can re-engineer the old drums to my new axle and fab up some motor mounts to finalize my engine spacing. Very intrigued to see how this thing run/drives under load...

 

[CTE007]

few pics

 

[CTE007]

The two pics in the grass was the test to see if the cvt's would work. Everything "snug" while the engine sit on a 2x6 to clear the tranny. Garage pics was with engine sitting on fabbed up motor mounts minus the 2x6 lol. The bottom not bolted or welded yet, so dont pay attention to the belt alignment, clearing the tranny was main objective..

 

[CTE007]

update- got everything frankensteined in. The straight axle rear wheel hubs were able to go through the orginal brake drums hubs same bolt pattern. Put lug nut studs through both, mounted tire. Just had to make new backing plates, and torch out a big enough hole so my straight axle hubs would go through. Mount new mounting plates to the orginal drums and weld them down. Able to use all preexisting brake hardware.Works great, doesnt look that great. Should verify that axle is center before you make patterns! Duh! One side had the addition of spacers, luckly i caught this before i welded the otherside. Just made a new one for the unwelded side. What's that saying measure twice cut once?

Correction the motor wasnt a gx390 but a gx340..
I need to salvage around and find a Polaris trans brake. the tranny has a spot to add a brake not sure if it was used as the Polaris's vechicle brake or just for a cvt stop. I do know that if you hit nuetral on the tranny the cvt will spend up w/o a way to stop them so you can not shift gears.... Kill the motor and put in right gear re crank has been the method so far.
As far as the clutch interaction Comet or CVtech drive to Polaris driven. I know i need a new belt. The one Im using has a 3 inch gash on the inside of it and was looking worn before i even started this madness. However, underload with 2, 200lbs adults i would guess it does 18-22 mph? We had a UTV drag race, funny crap I know. My brother's utv vs mine, i smoke his butt. His Utv is a chinese version 10 hp with the engine and tranny made together . I have not noticed any belt slippage, and the driven polaris pully opens per design. I dont know how much the driven opens, but looking at the whole circumference of the pully i've seen it maybe 3/4's open underload.
Does anyone know if the polaris driven open more the 3/4's?
Does 18-22mph sound about right for a stock gx 340 in bulky UTV with 2 adults?
I know its rigged to work, just would like any insight on the efficiency of the rigging.
Cheers.

 

[CTE007]

Oh one more Rigging problem, since i raised the motor probably about 3 1/2 inches, It put it above the stock gas tank that sits under the seat. I had to mount a temporary gas tank above the engine on the utv bed area. The gas tank under the seat is probably a 2 1/2 gallon to 3.. I would really like to keep it and its location however i cannot raise it up to let gravity do its job. i may can get its output petcock to the level of the carbs input. Is that a functioning senerio? Or does the gas tank need a sufficent height level to let gravity do its thing?

 

[Felineman]

Can I make a suggestion? change the comet drive to a polaris drive all crank shafts should be the same size so its as easy as undoing one bolt and pulling comet off and sliding on a polaris drive.

 

[CTE007]

Actually the polaris drive is a different size, it bigger than a inch aka the honda crank size. There however is a 40 buck adapter and involves shorting and taping the honda crank. Saying that i got a polaris drive on the way.

 

[CTE007]

I didnt want to have to jack with weights on the polaris drive to sync it with the lower reving honda motor. Switching is always a option why i bought the polaris drive. I guess also i wanted to see if it would work. Everybody said it wouldnt work everywhere i searched and looked for info about doing this. From a utv perspective it does work, there not hotrods anyway, for a go cart squeezing every last bit of speed out of it's probably not so efficient. Also it was one of those use what you got scenerios

 

[Felineman]

OK must have been thinking about another motor then, my bad. Anyways time for bed for me