Cheap strong reliable engine?

[Riptide]

I picked up a really nice mod sled chassis. The engine is a blown up 1000ccish triple based off a rotax 800 triple (809 cases). I have not quite given up on trying to find parts for the 809 as I know there are some out there (and pretty pricey) but I am starting to get a little discourged. I am starting to look at some different motor's. I am kind of thinking 670 rotax because there are so many out there and parts are cheap. I also know a few guys have built up some monster HP Cat engines. I am not a brand loyalist or purist for that matter. I will stick a cat in a doo or poo in a cat etc etc.

My question is what is a cheap, reliable engine, decent power that will take to performance addition's later on down the road? Ski doo, Polaris, Arctic Cat, Yamaha.

Interested in constructive comment's (READ keep the BS brand trashing out of the thread please)

The sled is 1999 zx chassis 154ish with 2" lugs, drop and roll kit, simmon's ski's, lexan hood etc etc

 

[d mills]

Good, fast,cheap. pick any two

 

[DRD]

Slap another triple in it, 780/809. Probably the least amount of work. Check the Doo talk classifieds, sometimes cheaper to buy an entire sled.
What went down on the mod triple? Stock jugs or aftermarket?

 

[teeroy]

670 rotax twin

 

[Riptide]

it was 809 crankcase, .25" spacer plate between crankcase and cylinders, cylinders bored and sleeved to 76.5mm, crankshop pipes, and a shaved head. I'm not sure if the crank was stroked or not but it was welded. Whoever rebuilt the engine forgot to put a bolt in the stator cover and leaned mag side piston. Piston melted down and seized, snapped the con rod, the broken con rod wanted some fresh air and punched out the crankcase and part of cylinder. In truth pretty near the whole engine is junk. Will need new crankcase, new crank, a core cylinder bored and sleeved, new 76.5 mm piston.

I'm just trying to keep thing's cheap. I was under the impression the 780's had cooling issue's? For the most part this will be a mountain sled, I have my 94 summit for ditch bangin

 

[DRD]

Engines-Triple Twin Zx - Classifieds - DOOTalk Forums

 

[MtnMaster]

SRX 700 triple... Some mild porting, head, and bender pipes make a ridiculous motor. Plus, they are nearly bombproof!

 

[Clares240]

Brother owns an old 700 mm, I was thinking the same thing.

 

[Riptide]

Found an 809 crankcase for $125, need to find out if the seller will ship. If he does, then I think an 809 triple will be sliding back into this sled, as I have found a bunch of rebuilt cranks in the $400 range. A core cylinder is cheap but finding a custom 76.5 mm sleeve and piston may be difficult unless a sleeve and piston from a 583 slides in?

DRD Is right in that it would be the least amount of work, but the cost of used 809 stuffs is insane. 780 crankcases are $100-125 without even trying to look for cheaper, 809 crankcases $350-450

I looked on kijiji for yammy triples and didn't find much in the way of engines or engine parts, which kind of worries me if I melt something down later on down the road. I would have to find a complete engine as well....

I found 2 complete 670's for parts and should be able to build 1 engine out of the pair. He wants $600 for the pair....

ugg decisions

 

[moyiesledhead]

700 Yammy, or 670 Rotax. Two of the most reliable engines ever made. Can't go wrong with either one. My third choice, but probably a lot more work to put in that chassis would be a 700 Cat laydown. My m7 has been bomb proof.

 

[Riptide]

700 cat laydown? That's a newer engine correct? EFI?

 

[moyiesledhead]

700 cat laydown? That's a newer engine correct? EFI?

Yup. '05/'06. Probably quite a bit of work to put in that chassis, but a great engine.

 

[boydo]

i have a 700 mtn srx motor for sale not blown up just the rest of the chassis is done 780 906 8980 ph or text, summitboydo@gmail.com

 

[pete gads]

Hey riptide i have a 2003 zx with mountain, magic drop and roll, 159 with m/c skid, simmons skis, lite weight hood seat and clear gas tank, polaris primary and team secondary, two window digitron, all powered by brand new 827 ported polished and rk tek head and domes willing to deal on this to get rid of it.

 

[DRD]

Found an 809 crankcase for $125, need to find out if the seller will ship. If he does, then I think an 809 triple will be sliding back into this sled, as I have found a bunch of rebuilt cranks in the $400 range. A core cylinder is cheap but finding a custom 76.5 mm sleeve and piston may be difficult unless a sleeve and piston from a 583 slides in?

DRD Is right in that it would be the least amount of work, but the cost of used 809 stuffs is insane. 780 crankcases are $100-125 without even trying to look for cheaper, 809 crankcases $350-450

I looked on kijiji for yammy triples and didn't find much in the way of engines or engine parts, which kind of worries me if I melt something down later on down the road. I would have to find a complete engine as well....

I found 2 complete 670's for parts and should be able to build 1 engine out of the pair. He wants $600 for the pair....

ugg decisions

Sleeve is 1193-B if they used 780 jugs, 1222-b if they used 809 jugs. They show it as an 889 big bore but this is the same sleeve used to punch it out to a 925-950

Piston could be a 583 o/b but there is some BB's like Russ Lemke's 992 that used a TCat piston at 76.5mm
How much are you trying to get away with $$$$ wise?

http://www.lasleeve.com/downloads/2012-LA-Sleeve-Snowmobile-Catalog.pdf

 

[Riptide]

 

[Riptide]

I think they are 809's

DRD I'm on a REALLY tight leash right now, I can come up with $500 right now and probably another $250 in a couple weeks. That's why I was looking at the 670s (and others)as they are as cheap as dirt.

That's the reason I started this thread, to try and figure out some cheaper alternatives

 

[Riptide]

 

[Riptide]

another pic of some of the carnage

 

[Summiteer]

The 97,98 Polaris 700 motors were fairly bulletproof. Don't know how much HP you could squeeze out of them though.......