Polaris snowmobiles

 Hey guys, My names Sam, I'm 16, and a Motor-head. Saw there's a lot of knowledgeable guys on here for the 650's. Last season i sank my sled in a river(went right through the ice) Engine was shot and sled wasn't worth the money to rebuild so i got rid of it. My dad owned 4 650's(Indy's and RXL's) back in the 90's, he used to ride with Wayne Flo(Flo trailers) when he was just starting out, I've heard a few stories him beating down some of Wayne's *Ditch Pickles* with the 650's  . A few years ago he picked up a 1990 Indy 650 and we got right to modding it. Engines bored .40 over with Wiseco's (Prev. owner) Carbs bored to 39.5, Cone mount radiator, crappy set of dynoport pipes, newer edge chassis secondary(helps with the low end bog), Widened front end to 52" with custom Aircraft aluminum tie rods (was a kit back in the day) , sly dog ski's, Ohlins shocks all around, Xtra 10 suspension, New track, 96 studs. Its one of those sleds you work on more than you ride.

 Well, i don't have a sled this season so I'm going over it a bit. I Put new gas lines in, replaced the coils, cleaned carb's, painted up it a bit, replaced the trailing arm because 2 seasons ago my dad got bucked off the sled and it clipped a large rock, and I'm trying to get some better pipes for her. If anyone has a set fairly cheap (preferably PSI's or Decker's) I'd be interested. The sled has been troubled the past few years with fouling plugs/dropping cylinders. I only got 1 ride out of it where it didn't break down. When i tore the carb's apart i found 270 main jets, which are way to lean for running pipes. I'm surprised it didn't melt a piston, although the temp light came on several times(could have been from low snow conditions). I just put in some 360's because they are all i have right now. I started it up without the Can on and it runs real good, although the plugs look like its burning lean. I'm mostly looking for a reliable trail rider, but with the power to taker on the newer sleds out on the lakes. So if anyone's got pipes or some suggestions for me as far as power/reliability goes id like to hear it. Looking forward to talking with ya

http://i141.photobucket.com/albums/r52/squirrellrancher/1016091612a.jpg

http://i141.photobucket.com/albums/r52/squirrellrancher/1016091613.jpg

Hi!

Nice to hear!

On my XLT i raised the seat alittle, I just filled a lille on top of the foam with layers cut out of this outdoors sleeping layer, I cut the edges in in small angles so that they dont apear thru the cover.    

  http://gresvig.scene7.com/is/image/gresvig/716250?$ProductThumbnail120$

Relibillity:

The chain should be inspected, look for cracked plates. and keep it tight, possibly retight after every weekend.

Wisecos, really need to be idled hot to where the coolers feel hot before you go, fire it up before you put the clothes on. (They expand so fast they can cold size, and before that they rattle so piston skirts wear out)

Jetting:

1/8 to 1/4 throttle air-screw, pilot/slow jet

1/2 throttle needle

1/2 to full trottle main jet

I usually make an wot run first (Really short one first on an really hot engine in the coldest day, run on and of the trottle to cool the pistons while running around un tuned) then hit the kill switch while holding the trottle and keeping it untill sled stops (Remember to brake!)

Plugs should be light brown for most power or dark for safety.

Repeat at half trottle 

Then 1/4 trottle, running around at steady 1/4 trottle then hit the kill switch and keep trottle untill sled stops.

Adjust differntly between carburaturs and check that they all open equally.

If plugs stays grey or yellow the compression/timing is to high or water is too hot.

If you do this you get an perfectly running triple triple with no bogs at all!

I agree with Ove above. Another thing to add, check the belt for the waterpump to make sure its tight and not slipping - possible reason why it your high temp light came on. Another possible reason it may come on, it could be the crank bearing(s) is about to be going, causing it to work extra harder just before the crank is about to blow. Check that with the dialer to be sure or take the spark plugs out and listen for any "growling" noise as you turn the crank over. It could be bad sensor or the waterpump might be going. Or like you said, it could be low snow conditions thats NOT keeping the radiator cooled.

As for after market pipes, DYNOPORT is usually pretty good pipes - PSI or DECKER version, in my opinion - I think they are mainly more for setup for race application than it is to use for trails. Im not saying u cant use it for trail riding, but because they are peaky and higher revving. Power curves tends to be fall off. SLP and DYNOPORT are more trailable than the 2 aftermarkets that Ive stated above. Remember, thats my opinion. Unless you are planning on racing on the lakes, then PSI would win my vote. Anyone?

WL

the decker pipes worked great for me.  dynoed 127 at 9400  i only turned it about 9000 on the trail but would swap weights when lake running and spin it 9400. i always ran between 260's to 280's never any higher but with the thin head gaskets i had to becareful of fuel quality.  make sure you are regeared for the pipes, i would not gear it any for anything higher than about 100-102 mph. aaens were also very good.  remember this is a piston port motor so if you are going to be off on the clutching  let it over rev rather than lugging the motor down. i had always heard these motors had a harmonics problem from 8600-8800 and would break cylinder studs.   good luck

I have a set of PSI's for the 650, I have a guy looking at them at the moment but not sure he's gona take them

I'll know by the end of the weekend.

Oh Boy, does this bring back some sweet Memories.

I used to own an 88 650 that had the Engine completely done by HTG. It was strictly for Drag Racing tho. It was an O-ringed motor ( 195 lbs. cranking compression with fresh top end) with quite a bit of porting around the transfer ports and the crank was built by Litner/Bush. It would run all day long at 10,000 rpms so long as you made sure it had lots of 110-116 Octane race gas ( Compression Ratio was 16:1 ) in the tank. Dyno rated at 165 hp at 9,800 revs. Had to run 350 Woodys 1 inch Chizels in order to get Traction.

I also had a 91 650 that I used for Trails only. It had some Clutch work. I had some weights in the Primary that had won me a few Bucks in Outlaw Races with the 88 plus an HPE Primary Spring and a EPI spring and quad helix in the secondary. Other than 20 over Wisecos it was stock and with 260 main jets would run like a Jewel all day and Night. It had 144 1 inch Studboys which were great for the trail. Stock exhaust too but, several Guys suspected it was a "Ringer" cause it ran a lot better than some of the new Iron around here. I like to think it was just properly set up is all.

If anyone is interested, I can dig out my Notes from when I owned both Sleds and give you exact Carb calibration/jetting and clutch wts etc. plus Studding location charts and some other Tricks I learned over all the time I had fun playing with these 2 Triples.

Today, I ride a Vmax-4 which is like a Cadillac compared to the Old style Indys but, a Guy could/can still have a lot of Fun with them Old Piston Ports especially with the right Tuning!

Good Luck with your 650!

Rob Former Owner/Tuner Oneshot Racing!!