Sled Rebuild

[crazycart]

This thread can be moved if a new section is created for other stuff.

So i have a 1989 Polaris sprint 340 snowmobile which i am in the process of rebuilding from the ground up as a summer project.I plan on sandblasting the whole bellypan/tunnel,and giving it a good paintjob.
I'm redoing the front suspension,and the rear,also converting it from a 116" track to a 121".The new-er track also has quite a few studs(steel carbide picks) which make it hook up good on ice etc...(WHEELIES)Im going to rebuild the engine(possibly overbore) shave the head,port the intake and exhaust,and rebuild the clutches.I will be mounting on twin SLP expansion pipes and MAYBE dual 38mm mikuni's(has 34's right now i think).

Hopefully ill have myself a good little sled to rip around on for fun this winter.This snowmobile is considered very small in the sled world,but i like it because it is very light and you can throw it around easy,i also have a 2005 polaris 550 twin and a heavily modified 1990 polaris 650 triple(which will exceed speeds of 100 mph).

Heres a few pics of it stripped down and the engine(broken piston skirt,but the cyls are in perfect condition)IUm still debating whether i should buy std. bore pistons or .40 overbore.Both kits are 30$ Im not sure how much its costs to get a bore job though..
Heres what it looked like before(crap lol)
http://i141.photobucket.com/albums/r52/squirrellrancher/mysled.jpg


http://i141.photobucket.com/albums/r52/squirrellrancher/P4090174.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/P4090175.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/P4090180.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/P4090176.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/P4090179.jpg

[oscaryu1]

Nice! It doesn't really look that bad before, but what am I to say? It snows every 10-20 years here haha :D

Nice project though. 2 strokes I suppose?

[crazycart]

Yup 2 strokes :thumbsup:

That was also and older pic of it,it looked alot worse recently,and it had a horrible bog,the steering was very clunky,rear suspension sucked,track was in horrible condition, it goes on and on lol,mostly performance was suffering.haha and i also was driving it and it backfired and caught on fire and melted a bunch of stuff
Heres what it looked like COMPLETELY stock,fugly aint it?

http://www.polarisman.com/images/sno/1989sprint.jpg

[ironman]

hey crazycart let me see a better picture of that carb. setup on there.looks like my 292 setup

[crazycart]

Okay,this isnt MY engine,buts its basicly the same thing except for the shroud on top.

http://kijiji.ebayimg.com/i6/03/k/000/7a/12/5c05_20.JPG?set_id=1C4000

[crazycart]

A little update.I first used a cold galvanizing compound( 93% zinc) which stops rust.I then primered,then used RustOleum Professional Flat Black.Turned out pretty nice for spray paint.(ran outa black lol,so its not done yet.)
http://i141.photobucket.com/albums/r52/squirrellrancher/P4140181.jpg

[crazycart]

Finished painting.Also made a handlebar riser out of angle iron and square tubing.
http://i141.photobucket.com/albums/r52/squirrellrancher/P4150183.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/P4150184.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/P4150185.jpg

[oscaryu1]

Gonna ride it on the streets ain'tcha? :D

[crazycart]

lol thatd be quite a ride on this thing.Ive done it before though :roflol:

Check out this vid its just insane.
http://www.youtube.com/watch?v=FtXBm6VF_Zo

[crazycart]

I also do quite a bit of "water skipping" :thumbsup: Who sais you need a jet ski for fun on the water?
http://i141.photobucket.com/albums/r52/squirrellrancher/MESKIPPINNNN.jpg

[Kenny_McCormic]

LOL, be careful doing that.

[crazycart]

Ive actually ran out of gas while going over water,not a fun experience lol.

[gocartkid]

Ive actually ran out of gas while going over water,not a fun experience lol.

I hope you know how to swim! :roflol:

[kibble]

Ive actually ran out of gas while going over water,not a fun experience lol.

LOL! :roflol:

[ed1380]

Ive actually ran out of gas while going over water,not a fun experience lol.

:oops:

[crazycart]

Well 2 weeks ago i dropped off the engine at a machine shop to get bored for the .40 over pistons, and i painted some suspension parts.This project has been goin kinda slow lol

[crazycart]

Got the cylinders back. 90 bucks for boring and honing. i cant wait to get this thing goin.
Wow what was the machinist smoking on? Thats a extremely good price for that work!

[JerryAssburger]

I think the sled kicks _ss even stock! Is it the same kind of motor as "Ed's Black Terror Kart of Death" motor. (A 440cc twin aircooled.) If so... it's gonna fly without making a mark in the snow. I am a real fan of those Polaris/Fuji twins.
http://i107.photobucket.com/albums/m290/jerryassburger/100_0651sml.jpg

[crazycart]

Yeah its a 340 just newer model engine. Its rated at 38HP stock. Which really isn't that much in the sled world today. I have some twin expansion chambers im going to put on (they look BA!) and some dual Mikuni 36mm Carbs(stock is like 32) Its also bored out, and i got a newer clutch for it, newer clutches are a goodway to get all the power to the ground(or snow).We put a new secondary on our 1990 Polaris Indy 650 (Triple Cyl. Liquid cooled,triple pipes, lots done to engine) Its rated at about 120-130 HP, and that clutch made a huge difference in the holeshot. Hold it wide open and it'll keep the skis up as long as you want. Sorry for rambling on about this, but i love it lol...

[2or3wheels]

snowmobiles are so fun. Want to know a real sleeper snowmobile. Our 85 ski doo MX 470 LC. Some how, stock set up, keeps up and or passes my aunts 98 polaris 500 LC. Has not been re-built it in a long time. the primary has a odd noise but we feel if it aint broke dont fix it.

On another note how do you "summerize" or store your sleds? we always run seafoam or stai-bil through like 5 gallons and run the carbs completely dry. Us personally have never had any problems.

[crazycart]

Well the 500 LC's arent very fast to start with, about 90 MPH sleds. The 650 will do 110+ with good hardpack conditions.And it looks like sleeper til ya fire it up, them triples sound awesome.Its got 96 studs, but needs more because of the power.

For summerizing we usually do that or spray marine storing spay into the carbs and down the plug holes. Also run it dry.

[Kenny_McCormic]

snowmobiles are so fun. Want to know a real sleeper snowmobile. Our 85 ski doo MX 470 LC. Some how, stock set up, keeps up and or passes my aunts 98 polaris 500 LC. Has not been re-built it in a long time. the primary has a odd noise but we feel if it aint broke dont fix it.

On another note how do you "summerize" or store your sleds? we always run seafoam or stai-bil through like 5 gallons and run the carbs completely dry. Us personally have never had any problems.

Carbs should be left full of treated gas so should the tank if metal, Spray some WD40 down the plugholes so it doesn't seize up.

[2or3wheels]

we had the sleds sittin for 2-3 years and they didnt sieze.

[crazycart]

I left the one im rebuilding out for 1 winter without 1 of the carbs on and it seized.

[crazycart]

Pics of the engine mocked up, just need gaskets.
http://i141.photobucket.com/albums/r52/squirrellrancher/10-16-08_1803.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/10-16-08_1804.jpg

[newrider3]

My friend said he just got in a new pipe, Fox shocks, and a turbo for his sled. I believe it's a Polaris Triple. Yes, I said turbo.

[Kenny_McCormic]

Turboing a 2 stroke is pretty close to pointless.

[Russ2251]

Turboing a 2 stroke is pretty close to pointless.:iagree:Yeah, kinda'.
Added weight just makes it a wash.

[crazycart]

Turboing a 2 stroke is pretty close to pointless.

You sir, are completely wrong.

Turboing a 2 stoke makes INSANE horsepower. But of course, is very hard to tune. Usually not necessary unless mountain climbing or drag racing, because its very complicated and expensive to set up. It may seem like it would be pointless on a 2 stroke, but it makes ridiculous power.

[Kenny_McCormic]

Huge tuning issue from blowing fuel out the EX port, way more power adders beofre a turbo.

[crazycart]

The thing is, the intake and exhaust ports aren't exactly in line, and with the powervalves on modern 2 strokes, it works. There isn't a better power adder than this, horse power can be increased by 45-50%. And that's big numbers when you have a sled that's running 175hp stock.

[Kenny_McCormic]

Power valve, I learned something today!

[newrider3]

Well I pulled the ol "pics or STFU", and it looks like he wasn't lying. Not a Polaris though.
http://c3.ac-images.myspacecdn.com/images02/36/l_88c483036cd249da908f9530b4b7ac2e.jpg
http://c1.ac-images.myspacecdn.com/images02/29/l_bd41e887dd1642a59bda8d224a6a8c84.jpg

[crazycart]

ITS ALIVE!!! The engine runs. 1 step closer.

[crazycart]

Short clip - http://s141.photobucket.com/albums/r52/squirrellrancher/?action=view&current=10-25-08_1718.flv

http://i141.photobucket.com/albums/r52/squirrellrancher/10-25-08_1804.jpg

http://i141.photobucket.com/albums/r52/squirrellrancher/10-25-08_1805.jpg

[Kenny_McCormic]

I wish I still had that 650. Dad just had to get rid of it before I got the cash around to rebuild it(and he gave it away at that). This thing was ****ing sweet, 650 3 cylinder liquid cooled fuel injected 2 stroke with studed track, a Polaris indy IIRC. Dealer wanted $200 for the piston it needed.

[crazycart]

That would be a Polaris RXL. Same as the one i have, just with fuel injection. These had 44mm intakes too. My dad had 3 of them. Fast sleds.

[Kenny_McCormic]

LOL engine strapped to table, WIMP!

[jr dragster Tyler]

LOL engine strapped to table, WIMP!

Lol nothing like using your foot on the head, That's all ya need.

[crazycart]

A twin cylinder 38 horse a bit more than a little 5 horse..the thing shakes the strap loose lol...

[crazycart]

I'm getting another sled, a Yamaha Exciter 570 liquid cooled twin, runs perfect. Did i mention free?

[Kenny_McCormic]

I HATE YOU

Cant get a rotted out 70s 300 for under $200 around here!

[crazycart]

ROFLMAO

I saw that response coming. These things are quick sleds too. Makes around 85 hp... JUST MORE SHIAT TO ADD TO MY SHIAT COLLECTION!

[kibble]

Crazycart, just got one thing to say to you:





















YOU SUCK!!!

[crazycart]

Lolllll and i usually don't even look for this stuff , im just in the right place at the right time...

[crazycart]

Well i got the sled....and three bucks [male deer]. Anyway, im in love with it already, even though Yamaha over-engineered the hell out of it. Pics will come tomorrow, i have it apart and am cleaning the carbs, what a PITA

[2or3wheels]

OOOOO so this baby has that werid front shock set up right?

[crazycart]

Yup. I believe its called TSS. "The Sh!ttiest Suspension" Also has "TORS", throttle override system, so if the carbs are stuck open it wont start, liquid warmed carbs, a bunch of unnecessary switches and such, over engineered rear suspension, handlebar mounted light, speedo, tach.[If you roll they are broke] Otherwise its a good and light sled that will keep up with the bigger modern sleds, and pull the ski's :thumbsup:

[crazycart]

FREE FREE FREEEEEE

Heres some pics of the FREE sled

http://i141.photobucket.com/albums/r52/squirrellrancher/11-11-08_0741.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/11-11-08_0743.jpg

[kibble]

Please refer to post #44.... :arf:

[crazycart]

Lol....

WOO i woke up to a winter wonderland! [it snowed] Hopefully it wont melt...

[crazycart]

I thought i'd post a few pics of the 650 to get in the spirit of winter. Under the hood is a Triple Cylinder 650cc with Triple Dynoport expansion chambers, Triple Mikuni 39.5's, bored .40 over, rated around 125 HP with the pipes alone.

http://i141.photobucket.com/albums/r52/squirrellrancher/12-01-08_1331.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/12-01-08_1332.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/12-01-08_1333.jpg

[Kenny_McCormic]

I thought i'd post a few pics of the 650 to get in the spirit of winter. Under the hood is a Triple Cylinder 650cc with Triple Dynoport expansion chambers, Triple Mikuni 39.5's, bored .40 over, rated around 125 HP with the pipes alone.

http://i141.photobucket.com/albums/r52/squirrellrancher/12-01-08_1331.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/12-01-08_1332.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/12-01-08_1333.jpg

I used to have one of those! It had been modded with EFI! Got it for free but dad didnt want to put $400 in it to rebuild the cylinder that ate a rock.

[crazycart]

EFI isnt a "mod", its a different model. This is the INDY 650, you had a RXL 650. They rip pretty dang good. Oh btw, these are 95 hp stock. The pipes add around 30 HP!

[Kenny_McCormic]

No it had RXL parts in it then, everything on it said indy but under the hood told a different story.

[crazycart]

Ah I see. My dad had 3 of these back in the day, 1-2 rxl's. They were the fastest sleds around. They still are pretty quick. 110-115 mph.

[Kenny_McCormic]

Its semi good its gone now, **** thing probably would have killed me if I got it going. I just got a motorcycle that will do nearly 80, lets see how long it takes before I get bit.

[crazycart]

It wont be long, that's how it always is, ya get something fast, your gunna get hurt. I know i've eaten it a few times on my bikes. My dad crashed that 650 last year and broke his ribs.

[Russ2251]

Let's face it. A big part of this stuff we do is knowing we may not live to tell about it. The trick is not to be stupid about it.

[jr dragster Tyler]

I havent been hurt racing yet. There's been a few close encounters though when breaking in new tires.

[Russ2251]

Every bodies number comes up sooner or later.
Mine came up a couple times.
It's rare that I'll even look a motorcycle anymore.

[crazycart]

Well, it isn't related to the sled rebuild, but it is to snowmobiling. Put 70+ miles on 1/1/09
This trail will go all the way to Duluth, of course i didn't go that far. I rode that old exciter! Didn't break down once.
http://i141.photobucket.com/albums/r52/squirrellrancher/01-01-09_1412.jpg
http://i141.photobucket.com/albums/r52/squirrellrancher/01-01-09_1413.jpg

[jr dragster Tyler]

Ahhh reminds me of the road's around the track.

[oscaryu1]

Over here in Texas, you can't go 4 feet without encountering another car.

I is jealous.

Also refer to post #44 :)

EDIT - I WANT THAT PIECE OF ROAD!

[crazycart]

Hahahaha. Also, this isn't a road, its a snowmobile trail..lol.