[TheCirque]

So I recently had to purchase a crank for my 2005 snowmobile. It's a Polaris 900cc, twin cylinder. I'm in the process of rebuilding the motor after I sheared a crank pin. Seems most owners of these sleds are doomed to a similar death as me. Lots 'o probs for Polaris.

The crank cost me $1200 plus tax. Again, TWIN cylinder. No pistons, rods, bearings included in that price. Crank only.

I then see this previous post here for a cast Eagle crank at $285. 8 cylinder.

I know there are a zillion more car motors out there than snowmobiles but SERIOUS... $1000 price difference?

It makes rebuilding my 455 seem almost reasonable! Sheesh.

[propuckstopper]

Although I am not familiar with that exact year, many Polaris Fusions (900cc) had bad engines.

All that aside, how did you manage to purchase a two-stroke crankshaft without connecting rods?

All the two stroke stuff I have ever seen have press-fit crankshafts. The cranks are pressed together from many pieces, unlike a one-piece Cheby or Pontiac crankshaft.

There is no bolting a connecting rod onto a crankshaft. The cranks are "built-up" using counterweights (referred to as "wheels" in the trade), crank pins, bearings, and rods. The whole thing needs to be pressed together, phased and checked for runout.

Every rebuilt crankshaft I have ever seen in the two-stroke category always has the rods attached. It cannot work any other way.

Once these cranks are fully assembled, a brass hammer is used to beat them into specs. They are then put into the two-piece crankcase, where further assembly becomes necessary.

Twelve bills is horribly rich for a two cylinder, two-smoke (stroke).

Call Northern Crankshaft in Thief River Falls, MN for a quote, if only for comparison.

[TheCirque]

I stand corrected. You are right... Connecting rods were part of the deal... Pressed on and part of the crank assembly. Thanks for reminding of that... So there is little more value there.

I guess my bigger point is how can there be such a price difference between the two? This thing is minuscule compared to a v-8 crank and costs 4 times as much. Hell, a sweet forged crank for my 455 is still cheaper. I gotta get out of the sled biz and concentrate on the GTO!

[Schurkey]

Virtually no aftermarket to keep the OEM honest?

OEM knows it's just a toy; so they have no mercy? Besides, the more expensive the replacement parts, the more likely you are to screw it, and buy a new sled.

[gillyiowa]

Send it to a snowmobile crank shop. Most decent shops will double pin the cranks, getting rid of the stock set-up. These are two of the better places.
http://snowmobilecylinders.com/crankshaft_repair.html
http://www.thecrankshopvt.com/index.php?cPath=21_40

most can be rebuilt for under $500

[tpssonic]

Next time call Doug Flannery at Flannery Motorsports, Gun Lake, MI (616) 792-0070. He has rebuilt a number of crankshafts (all makes) for me, and at a fraction of the cost of new. Plus, he will have upgrades for that crank to address the (con)Fusions' awful harmonics issue(s).

Tony

[cdrookie]

i had an 06 900 fusion, absolute beast of a sled. the lieing thieving sob i bought it off of had some work done to it though. i only rode it a few times and he wanted me to sell it back to him(he still owes me big money)...anyways... after he stole it back i got an 800 skidoo and it let loose after 1500 miles. i got a remanufactured crank off ebay for $600. the price of parts in the powersports industry has always been crazy compared to cars. i had $2000 in that twin cylinder 2 stroke skidoo motor...

[tpssonic]

Unfortunately, those are two sleds that have reputations for eating cranks- even in stock form. Both have great power out if the box, however (136- 150 hp). I have over 15,000 miles on my Polaris Ultra (triple) original crank and original clutch. I have built 18 Polaris Ultras varying from triple-piped 680cc (stock displacement) making 145 hp (stock 680cc single piped engines make about 106 hp) to aftermarket (Crank Shop cylinders) piped 1000cc making over 245 hp (all pump gas sleds) and they are all still on the original cranks, except one that got hydrolocked, which knocked it out-of-phase a couple of degrees. It stall ran, just not as well The triples are much smoother than the twins (and much easier on the cranks and clutches), albeit heavier, which is not the greatest for mountain riding. There, "light makes right" and a good turboed twin gets it done with aplomb- and the altitude doesn't affect power output with the turbo. All of my 600cc sleds are twins, and my 601cc-1000cc are triples. Once you get past 600 cc, the bore to available port area ratio suffers with the twins, which results in less power.

By the way, my little 440cc rotary valve twin made 136 hp on the dyno (race fuel) at 10,200 rpm. It didn't engage the clutch until 7,200 rpm, which is when most Ponchos are done spinning out power. Keep in mind, however, the sleds I am referring to are two-strokers,

Yes, powersports pricing is nuts.

Tony

[propuckstopper]

Originally Posted by cdrookie

i had an 06 900 fusion, absolute beast of a sled. the lieing thieving sob i bought it off of had some work done to it though. i only rode it a few times and he wanted me to sell it back to him(he still owes me big money)...anyways... after he stole it back i got an 800 skidoo and it let loose after 1500 miles. i got a remanufactured crank off ebay for $600. the price of parts in the powersports industry has always been crazy compared to cars. i had $2000 in that twin cylinder 2 stroke skidoo motor...

If that is an 800R Ski Doo, sell it before you lose another crank. There are huge known issues with their cranks/crankcases, and they are a nightmare. Most run about 3500 km (2100 miles) then they let go. A local repair shop here in Canada (crank shop) is full of blown up 800R engines. I don't know how Ski Doo has gotten away so easily given the huge amount of failures of these engines.

Some here may disagree due to the age of the sled I am about to suggest, and some may disagree due to the limited suspension system. But if you are looking for reliability, great power, amazing trail handling, and an overall wonderfully engineered sled look no further than a 2001-2002 Yamaha SRX 700. I have owned over 15 sleds in my lifetime and this is by far the best sled I have ever owned. Comparatively, my 2006 Arctic Cat F7 SnoPro had a beautiful ride, and was great for ditch banging and other general rough stuff. But on a smooth, heavily treed, lots-of-twisties groomed trail, my SRX would eat the F7 for lunch. It would also outrun the F7 in a long drag race. These sleds drive like they are on rails. Just don't hit any big bumps!

If you are looking for a slightly detuned version of an SRX with better suspension (although still not great), try a 2002 Yamaha SXR 600 or 700. This is the sled my wife rides, and these "red-head" Yamahas are said to be even more reliable than the SRXs due to their slightly detuned nature. They have no power valves, and a single exhaust. They still go like stink, and are super easy to maintain.

We get wicked cold weather here, and ride deep in the bush. The last thing I want is to be on an unreliable sled, because freezing to death just kind of sucks

[cdrookie]

it was an 05 mxzx. my buddy bought it from me and i upgraded to the pro r/rush sleds.

[BruceWilkie]

Originally Posted by propuckstopper

If that is an 800R Ski Doo, sell it before you lose another crank. There are huge known issues with their cranks/crankcases, and they are a nightmare. Most run about 3500 km (2100 miles) then they let go. A local repair shop here in Canada (crank shop) is full of blown up 800R engines. I don't know how Ski Doo has gotten away so easily given the huge amount of failures of these engines.

Some here may disagree due to the age of the sled I am about to suggest, and some may disagree due to the limited suspension system. But if you are looking for reliability, great power, amazing trail handling, and an overall wonderfully engineered sled look no further than a 2001-2002 Yamaha SRX 700. I have owned over 15 sleds in my lifetime and this is by far the best sled I have ever owned. Comparatively, my 2006 Arctic Cat F7 SnoPro had a beautiful ride, and was great for ditch banging and other general rough stuff. But on a smooth, heavily treed, lots-of-twisties groomed trail, my SRX would eat the F7 for lunch. It would also outrun the F7 in a long drag race. These sleds drive like they are on rails. Just don't hit any big bumps!

If you are looking for a slightly detuned version of an SRX with better suspension (although still not great), try a 2002 Yamaha SXR 600 or 700. This is the sled my wife rides, and these "red-head" Yamahas are said to be even more reliable than the SRXs due to their slightly detuned nature. They have no power valves, and a single exhaust. They still go like stink, and are super easy to maintain.

We get wicked cold weather here, and ride deep in the bush. The last thing I want is to be on an unreliable sled, because freezing to death just kind of sucks

Excellent choices... Alternately a little less money and power, any of the 98 and newer SX's are very good in terms of reliability and great handling... My 99 SX500 was a blast... 96 studs and a good set of carbides along with a Bender clutch kit V-Force reeds and good tune it did pretty good for a 500. My friend wasnt happy when I beat his Polaris Ultra SPX700(680) triple with triple pipes(heavy pig that rode way too mushy) 1/4 mile we had marked off. Insisted I wasnt runnin 500 cc's and sayin Yamahas cant hook like that... My holeshot was just enough for the win he almost got by me lol. I test rode the 11" travel suspension XT version... very cushy ride(marshmellow) but nowhere near the SX for looks, fun factor or handling. Took some serious bumps with my SX... it didnt exactly bottom but you knew you hit somethin. Never wore me out on long rides. Sled never gave any problem over 7000 miles I piled up on it over 6 years just routine wear n tear stuff. Wish I still had it.

My brother-in-law has gone through several cranks on his Ski doo 800... He spends more time fixin it than riding it I think... However my old 77 340 Everest(1st sled) is still around... its my brother-in-laws backup lol. A former relative had a late 90's 670? (iirc) that ran strong... till he played with N2O for awhile... Was a guy runnin a heavily modded formula 500 runnin with the 800 class sleds...bullet 1/8th mile or less but couldnt beat my kid on his Phazer 2 on a winding twisty trail. I'm not a Skidoo fan.

I kept one sled when I moved south...My old 80 Kawasaki Invader... and a couple motors. The original 340 and a 440 LTD 4/6 motor from a wreck... I keep it in NY at my sons place.(Tug Hill region) Was doin the vintage races with it... set the 340 up with the LTDs twin pipes and bumped the compression and a bit of port work and some flatslides off a Yamaha V-max 4. The 340 is slightly faster than the stock LTD 440 4/6 combo. The 340 races well though old Yamaha and Rupps were tough to beat. Fun for a short trip to the sled hang outs... gets attention... Still pretty sharp lookin sled.

[tpssonic]

"If you are looking for a slightly detuned version of an SRX with better suspension (although still not great), try a 2002 Yamaha SXR 600 or 700. This is the sled my wife rides, and these "red-head" Yamahas are said to be even more reliable than the SRXs due to their slightly detuned nature. They have no power valves, and a single exhaust. They still go like stink, and are super easy to maintain."

The SXRs are great sleds, as are the SRXs. The 1997 SX (red sled) was a triple as well, and properly-tuned) and would deliver an additional 20 hp with triple pipes at a much lower weight and would rival the stock SRX 700's power/performance without the power valves. Also, the SX was one of the VERY FEW stock sleds that would produce more power with an aftermarket silencer (Tim Bender of Grand National fame was one of them) for the stock single pipe. Sadly, most aftermarket single pipe silencers made LESS hp than the stock mufflers...and at a much higher decibel level. The SRXs and SXRs are some (IMO) of the smartest-looking sleds on the snow. If you're considering purchasing an SRX, the latter-year models are (in the words of Oscar Goldman of $6 million Man fame),"better..,stronger..faster...". Yes I have just date-stamped myself.

The Viper 700 (power-valved- equipped) with the stock single pipe could deliver about 28-30 hp with certain aftermarket triple pipes (they are NOT all equal). The king of aftermarket pipe-friendly sleds is the Polaris Ultra. Between 35 hp and 45 hp are easily achieved by just bolting on a set- some sets are no louder than stock (you don't have to be loud to be fast). This is part because of the stock wild porting and digital ignition. Bear in mind there MUST be jetting and clutching changes (as well as ignition lead changes, depending on time of run in manufacturing) to make a very strong and reliable runner- very capable of beating 800cc and 1000cc sleds. The Ultras have stout stock cranks that can handle the additional power. A stock Ultra is a pooch in stock condition (like a 450 cfm headed 455 with log-style exhausts) and received a bad reputation as a piston-seizing machine if not jetted, clutched, and timed properly with the addition of pipes.

Why all this sled gibberish? As many of the PY posts have stated, it all comes down to parts that complement each other...and TUNING.

Tony

[propuckstopper]

Originally Posted by tpssonic

"If you are looking for a slightly detuned version of an SRX with better suspension (although still not great), try a 2002 Yamaha SXR 600 or 700. This is the sled my wife rides, and these "red-head" Yamahas are said to be even more reliable than the SRXs due to their slightly detuned nature. They have no power valves, and a single exhaust. They still go like stink, and are super easy to maintain."

The SXRs are great sleds, as are the SRXs. The 1997 SX (red sled) was a triple as well, and properly-tuned) and would deliver an additional 20 hp with triple pipes at a much lower weight and would rival the stock SRX 700's power/performance without the power valves. Also, the SX was one of the VERY FEW stock sleds that would produce more power with an aftermarket silencer (Tim Bender of Grand National fame was one of them) for the stock single pipe. Sadly, most aftermarket single pipe silencers made LESS hp than the stock mufflers...and at a much higher decibel level. The SRXs and SXRs are some (IMO) of the smartest-looking sleds on the snow. If you're considering purchasing an SRX, the latter-year models are (in the words of Oscar Goldman of $6 million Man fame),"better..,stronger..faster...". Yes I have just date-stamped myself.

The Viper 700 (power-valved- equipped) with the stock single pipe could deliver about 28-30 hp with certain aftermarket triple pipes (they are NOT all equal). The king of aftermarket pipe-friendly sleds is the Polaris Ultra. Between 35 hp and 45 hp are easily achieved by just bolting on a set- some sets are no louder than stock (you don't have to be loud to be fast). This is part because of the stock wild porting and digital ignition. Bear in mind there MUST be jetting and clutching changes (as well as ignition lead changes, depending on time of run in manufacturing) to make a very strong and reliable runner- very capable of beating 800cc and 1000cc sleds. The Ultras have stout stock cranks that can handle the additional power. A stock Ultra is a pooch in stock condition (like a 450 cfm headed 455 with log-style exhausts) and received a bad reputation as a piston-seizing machine if not jetted, clutched, and timed properly with the addition of pipes.

Why all this sled gibberish? As many of the PY posts have stated, it all comes down to parts that complement each other...and TUNING.

Tony

Agreed. You really know your sled stuff!

[tpssonic]

Thanks propuckstopper,

I am now at the basement of the learning curve of Pontiac-speak. It's a humbling experience, but it's all good. It's been a great ride thus far with all the knowledge base at the Pontiac world-especially here at PY. Once I get my new drive train in, maybe I'll be able to blaze a few new trails and provide some information as well.

Tony

[beemergary]

Stay away from any Ski Doo with sealed crank bearings.

[PONTIAC-ONE]

Originally Posted by beemergary

Stay away from any Ski Doo with sealed crank bearings.

You can go to a open end bearing on the PTO (clutch) side and drill a oil feed hole.
That's been done around here for years.
My 800HO twin SKIDOO's PTO bearing went at 6660 miles, thats 4 years of riding & racing...then I did the bearing mod.
It was mainly a grass and snow drag sled, it has a new owner now.
The old Yammis are nice & reliable if you want to keep it cheap, I could never go back to those old conventional seat types with your legs way out in front of you so your back takes all the beating. For the 100-200 mile trail rides we do the new rider forward style (all are copying Doo now) is the only way to go, XR 1200 DOO is an great sled.

[tpssonic]

"For the 100-200 mile trail rides we do the new rider forward style (all are copying Doo now) is the only way to go, XR 1200 DOO is an great sled."

Very true. I rode 100+ miles last Saturday afternoon, switching off between 1200 'doos and a Yammie RX1 (4-strokes). It the tight twisties on a groomed trail, the RX1 was a bit better, but when it got rough (about 5 miles of the 100+ miles) it was all 'doo- especially the long-sneakered 1200 (one of the 1200s was a long-track). It gobbled up the moguls like I mow through pizza. Both sleds are relatively heavy, however. This is important as I have had two low back surgeries, and digging either of those two buggies out of a big-time stuck, well, I may wait until spring....

That being said, neither of the sleds would have a snowball's chance (pardon the pun) in the hot place against my old-school, piston-port, 2-stroke, piped 1995 XCR 600 in the SMOOTH twisties, even being down btween 400-600 cc and some 30 hp.

This sled gum-bumping is excellent therapy until I can get my car out this spring- thanks!

Ride on.

Tony

[propuckstopper]

And most of all, whatever you ride, be careful out there!!!