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XP -500SS - Full Wet 450lbs!!

41K views 138 replies 37 participants last post by  LRD 
#1 · (Edited by Moderator)
Here are a few pics of the 500SS XP TNT with 16 X 137 X 1.75 track with quite a few mods to get it down to 450 lbs full wet ready to ride!!

The pair of Aux Driving lights weigh about 6 oz the pair and each has 35 watt bulb.
The LED tailight came from Dennis Kirk dirt catlog for about $35 and weighs 3 oz including the carbon fiber mounting plate I mAde that velcros onto the seat. I recovered the seat and its about 2" taller and firmer.

Good Luck
 
#2 · (Edited by Moderator)
Few more pics

Just above the sec is the horizontal brace between the jackshaft tower and the front shock tower. Also filled the left rear motor mount from the bottom solid full of Devcon aluminum epoxy. Also just above the brace is the carbon fiber front air box, it has through the hood intake plus one of the snorkels from the stock front air box for inside air intake.
 
#4 · (Edited by Moderator)
The very well vented hood and carbon fiber front air box that weighs about 8 oz

The PCS gauge with a couple of the face options. Its touch screen and by touching any gauge face or readout box a menu comes up and you can change to any other readout you want. Currently the gauge can read out
RPM's, MPH, Left and Right EGT's, Pipe Belly EGT, Intake Air temp, Throttle position in %, Coolant Temp and O2 Air/fuel Ratio and Fuel level Gauge, (E-Man and I haven't got that to work with the stock fuel pickup yet). It can Data Log all these readings but currently only way to read them is by downloading to the lap top, think their is optional software upgrade so it can be done on the gauge. Many other options available, 4 axis accelerometer, and GPS etc.
 
#6 · (Edited by Moderator)
Thanks!!

Some of the mods

Straightline Pipe/Can, about 11 lbs, very nice sound and not obnoxious

Lite primary clutch, 4 lbs less tha TRA III, WOW -Throttlle response, track response, night and day difference between it and the TRA, 55 mph track speed on the flat at 10,000 ft in CO in 20 inch of fresh from the night before

Plastic, foam, sway bar, about 8 lbs

Oil injection full tank and pump and lines, 10 lbs

OK got over 30 lbs off for $150 for a used clutch, think it was about $500 for pipe/can, this was how it started, I got pretty excited and inspired with this much weight off the front end without really doing anything

Aftermarket Head I recut to about 12.5 to 1

Boyesson power reeds (regular old two stage petals)

Removed the front heat exchanger and filled holes with an aluminum plate, 3 lbs loss counting coolant, rerouted hoses and used 1" thin wall aluminum tubes to replace couple feet of rubber hose, coolant temp stays right at 127 degrees except on hard frozen trail then would go to 145 to 150 for short periods

The only other thing that could lose a fair amount of weight would be a lighter gas tank, because of EPA vapor emissions regs the XP tanks are double wall and way 14 lbs empty!! An aluminum tank with a 50 thou wall of 11 gals would only weigh about 7 or 8 lbs.

My porting, fairly mild, only 195 degree exhaust, 800's and 600SDI 200 or over, did lots of work in aux exhaust ports though and intake side, transfers came perfect, best I have ever seen in a sleeved cylinder

Eliminating the front air box was very difficult, carbon air box and the aluminum frame to hold the nut plates for the cowling

Used Floats on the skis for a Yami app 1/2" shorter than doo to drop the front end so could get flatter angle of attack on skid

Rear skid 33lbs!!!!!!! Two Floats with the rear being a takeoff on a Yami rear arm, about the same thing that Timbersled did, built the rear arm last winter, used a TI front arm from Alternative Impact, incredible piece, have a pair of those tiny wheels for the rail tips between the rails up by the front shock

Slydog PowderHound Skis, worked awesome

Bumper off a XP summit 146 and shortened about 4"

Aux Driving lights from Pep Boys auto, 6 oz for the pair and only about $25 with 35 watt bulbs

LED tailight from Dennis Kirk dirt bike catalog, about $35 and only 3 oz with the carbon fiber mounting plate I made that attachs to the seat with velcro

Swapped the wide front end with a guy with a Summit X

One particluar day at 10000 ft in Colorado a Cat 800 injected used 8 to 9 gallons, 800R with aftermarket head 4 gallons, and mine still jetted so rich in mid that it fowled plugs in a couple days used 5.3 gallons, when its completely dialed should be pretty easy on gas and I don't
think I'll ever need to carry a can with it

It has the same flotation on the track as a 154X but because the front end is about 50 lbs lighter than the 800 and has same size skis that end float a bunch better, the biggest improvement for the sled would be if Camo made a 16 X 137 X 2 track

The goal was to build the ultimate crossover sled that could do everything well and even excell over a lot of stock sleds because of light weight and power to weight ratio, estimated Hp would be conservative 115, next project is to fix my Land & Sea dyno!!!

Its about 80 lbs lighter than a stock 163 X and it makes my wifes 550 rev feel like its made out of lead, think I have her convinced to let me build her one of these with just the basics, head, pipe, tunnel extension and rail extensions, track and summit front end swap and she is demanding electric start

I ran 130/290 spring in the pirmary and 1 heavy washer with 1 to 3 light washers at 10 to 12K ft in CO, secondary Dalton 42/38 helix with doo Green spring (grind off hook) for HPV sec, rate 180/303, clutching worked near perfect, all a total best guess, one light washer was overevving at 8100 to 8300 at 10000 ft, gearing 18/45, next year will try to get an Micro Belmont to make an aluminum 49 for the bottom

Also made a 2mm reducer bushing for the stinger in the pipe and tried it the last day, seemed to work, anyhow sled climbed with the 800's that day although we never found anything big enough that couldn't be climbed. Last time I had this much was years ago when I put a 617 in my Phazer but the weight went up to 445 lbs dry so not even close to this!!!
 
#11 ·
Hey Hey, dry weight should be around 370 lbs, 360 would match the lightest sled I ever owned back in the 70's, a Scorpion 440 Sting but the T has a track, suspension, reliable 115 HP, and on and on. If I do another one of these for Mrs LRD it will have electric start thanks to you and E-man. She never lets up on not having electric start anymore !!!!!

Good luck
 
#10 ·
Here is a link to PCS http://www.powertraincontrolsolutions.com/content-21.html
The gauge is E-Mans deal, he is a dealer for them. He originally had this gauge on his twin tirbo 170+ MPH mustang street legal drag car. The company wants to expand beyond cars into sleds and personal watercraft. E-man and I have been test dummies for the gauge to make it work in the elements.

Good Luck
 
#18 ·
I bought a singer heavy duty sewing machine a few years ago that can sew threw about 5 layers of leather. Have sewed stuff like this for years. I found some white closed cell foam at an upholstery shop that is very light and from a distance looks like white poly insulation board but is instead closed cell and very rigid. I then took the stock foam off the seat base and cut and shaped and glued up layers of the white foam so it would fit the seat base and glued it on with Goop adhesive. Next step was cutting and shaping the bottom of the stock foam to fit on top of about 3 to 4" pf the white foam. When all done the seat is about 1.5 to 2" talller. Next the really hard part was taking apart the black and yellow seat cover and using the yellow as patterns for cutting new black pieces out of snowmobile material and making them taller as the seat was now taller. Even harder was sewing this all together so it fit the seat. Not a perfect job but pretty good considering all the changes. I do remember some guys saying they had their seats redone in black by upholstery shops, I'd try one that does boats and canvas.

Good Luck
 
#19 · (Edited by Moderator)
I picked up a used one off a 600 HO snowhawk last spring with the idea that I wouldn't have to recut the taper in the clutch. Still had to recut the taper about an 1/8" deeper even after slotting the motor mounts 1/4" though. I have recut clutch tapers a few times over the years on my lathe, just have to really pay attention to what your doing and go slow and measure often.

Good Luck
 
#20 ·
Nice , what do you think about using the 09 everest summit 146 as a base to make a replica ( somewhat ) . It looks like they will bring it over here ( sweden ).
How will the sc-5m work on trail compared to the sc-5 , and what do you think of tip-up rails like they got on the Nytro XTX?
 
#21 ·
I initially was excited about this for a sled for my wife and then realized it would be about as heavy as her 550 summit with electric start and the 15 X 146 has about same flotation as a 16 X 137 just has the bigger paddles. Plus the T has relatively good suspension compared to those low life motion control shocks. So I am doing my best to convince the wife to let me get her a TNT and swap out front ends with somebody with a summit and put on a tunnel and rail extensions with a 16 X 137 X 1.75 track. Oh yeah the two sleds are priced about the same also. I really hate motion control shocks!!!

The summit has the cheapest suspension with the heavy parts and a skinny track, very dumb on the track!!!

Good Luck
 
#25 ·
Only further engine mods planned are getting the carbs completely dialed in. Its still rich on the bottom and mid. Been hoping for a little snow and low 30's day so I can take it out on a lake for an afternoon and wrench. Then maybe late trip to the southern Big Horns and try some different clutching. Am also thinking about snowchecking a 09 TNT with electric start and doing a much milder version of mine for Mrs LRD.

The only other weight to be lost of any significance on mine is the gas tank. The XP tanks because they are double wall for vapor emissions regs weigh 14 lbs.

Good Luck
 
#27 · (Edited by Moderator)
E-man has his stock gauge still hooked up and I pulled mine out. E-Man figured out how to tap into the stock sending units and hook to the
PCS gauge, such as water temp and MPH, TPS, etc. only thing that we haven't figured out yet is the gas gauge. Not to worried about it , when the season is over I will empty my tank and then pull the sending unit out of the tank and put my ohm meter on it and check it out to see how it is supposed to function and we should be able to program the gauge to match the sending unit. It is possible when they replaced my gas tank
they busted the sending unit, remember somebody posting that scenario last fall.

The gauge is quite amazing, way beyond anything I have ever had before and I think I bought one of the first Digitrons in the early 90's and have one of the large Race Paks plus a fiur window Digitron laying around in my shop.

Good Luck

PS: Really cool, you tap any one of the gauge faces and or boxes and a full list of all the sensors you have comes up and you can choose to put a different one in that box or gauge, move them all over the place in a couple seconds.
 
#28 ·
LRD~ MRS e-man here...is the electric start insistance from your Mrs kinda my fault??? LOL if so...sorry! But I LOOOOOVE mine......and I think the MR does too...no one needs to be double checking that I got my sled started! Makes my day easier thats for sure!

~Nik
 
#30 ·
Not entirely, shes been asking for electric start for some time plus you know she isn't as young as she used to be, next snow season she will be old enough for social security. Heh Heh wonder Who the first one to rat me out on this will be? Its just not natural to not be in a little trouble with her.

Good Luck
 
#31 ·
Hey, I was curious as to what adjustments were necessary when adding the lite primary clutch to make it rev correctly? Did you try it stock and with the lite primary clutch or just with the pipe, can and jetting mods? What was the difference stock to the lite clutch? I enjoy reading your informative posts.
 
#34 · (Edited by Moderator)
I used a 130/290 primary spring for the mtns with a 42/38 helix (stock T is 42) and a green doo (180/303) sec spring. TNT sec spring stock is Black (157/303) and 800R's have Purple or Violet (225/303). I guessed pretty good on the setup as only had to change primary weight washers by a couple and jetting one size on the mains. This setup worked good from 6000 to 12000 ft with 18/45 gears.

I rode in the Black Hills with a friend who also longtracked a TNT with the same pipe but with the TRA. We switched off sleds, the Lite primary with 4 lbs less weight than the TRA is MUCH more aggressive while the TRA feels a lot smoother with throttle application. The Lite could maybe be tuned to be a little less touchy on the throttle with a softer spring, maybe 130/260 or 100 260. My friend also has a Lite on the shelf and plans on having it machined this summer to use next season.

Oh yeah by AGGRESSIVE I mean whatever you do with your right thumb the track and sled have an instantaneous reaction. Black Hills was a bit scary first time out with it as to climb you HAVE to go through tight trees and just bumping the throttle put the skis in the air making it real interesting to get around the trees. Can't even imagene trying to ride an 800R there with a big track!!! At 10,000 ft and above in Colorado wasn't a problem as it was down on HP up there compared to 6,000 ft in the Hills.

Good Luck
 
#35 · (Edited by Moderator)
Excellent Job LRD, who did the screen venting? I did a little weight reduction on my 163 Summit X, here are some weights, some are published and some are weighted on my digital fish scale.

SHR 860 R Summit X

AAEON PIPE 8.1 STK PIPE 12.2
AAEON SILENCER 3 STK SILENCER 15.1
CAMOPLAST 2.5" POWDER EXTREME TRACK SAME AS STOCK AFTER HOLES AND EVERY OTHER CLIPS REMOVED
TIMBERSLED SUSPENSION 36.0 STOCK SUSPENSION 54.0
LIGHTWEIGHT BATTERY WM #ES9-BS 6.1 STOCK BATTERY 14.9
LESS 2 LBS FOR FOX FRONT SHOCKS -2.0
LESS 1.1 LBS FOR SWAY BAR.
UPPER A ARM 1.1
LOWER A ARM 3.6
BAFFEL -0.1
TOOL HOLDER -0.9
FRONT AIR BOX -4.5
HEADLIGHT ASSEMBLY -3.1
PIPE -4
3 to 2 BWK & Shaft -2
REMOVE OIL INJECTION -10

TOTAL WEIGHT LBS 56.2
SLED WEIGHT W/ E START 462
SLED WEIGHT AFTER SAVINGS 395.8
WITHOUT E START 374.8
 
#36 ·
The oil injection 10 lb # is the oil tank full plus lines and pump.

The starter flywheel is removed from the Lite primary clutch.

I do my own screening using Pet Proof screen material from Home Depot and 3M Super Weather strip adhesive to glue the screen on. Works very well.

Good Luck
 
#37 ·
LRD,,,,
Sorry to bring back an old post. I don't get on here much in the summer and I just saw this. You got my attention, on the 4 lbs savings of the clutch. Is the lite clutch tunable other than spings? no clickers right?
How do they hold up in the long run? I only get a few thousand miles of mountain riding on my tra3 and the bushings are shot.

Also, I have had guys tell me not to remove starter gears and flywheel weights because they say cranks need the mass on the ends to cancel vibration and supposedly make the bearings last longer..... I have always wanted to remove the weight on the mag side by the flywheel, have you ever tried it? It would seem if 4lbs off one end doesn't hurt, why not remove a pound or two off the other side too right?

I'll be the guini pig and try it if you think it will work. BTW I'm not sure if the 500ss even has the weight on the mag side..... The 6/8 ho's do for sure.
 
#38 · (Edited by Moderator)
The 600HO snowhawks came with the lite primary (PowerBlock 50) and they are a pretty long stroke motor and shake a lot more than the short stroke 500SS (600) so I figured it would work and has seemed to. Good friend also has a long tracked TNT but with stock TRA, after riding mine he liked the
Light Switch throttle response of the Lite and said he wanted to put a Lite on his. All you can adjust in the Lite is spring and weights. Will be getting the shockwave helix and that should give some easy fine tuning. Although I can change clutch weights in the Lite at the trailer in about
5 minutes (takes some big wrenches to get that cover off). Took quite a bit of work to get the offset right, had to cut the taper in the lite deeper and move the engine.

Good Luck

Note on PowerBlock clutches - Nov 2013, The newer few lbs heavier PowerBlock 80 are now being used on the Doo 1200 4-strokes to replace the TRA,s that shake to pieces. Also being used by a few on the 800 2-stroke engine.
 
#39 · (Edited by Moderator)
Here is a update on the mod longtrack TNT. Lost all last year do to back injury between Christmas and New Years.

Just had a (New Years 2009) one week trip to So WY in bottomless powder and sled performed very well.

Finally got to try out the new Cabellas 550 lb game scale and it says full wet weight right around 445 lbs with a dry weight of about 370 lbs.

Engine is now a 629 big bore with Wiseco 670 X flat top pistons with dual rings.

Did a couple experiments with the combustion chambers (Singh Grooves) 3 grooves, one aimed at center intake side and the other two aimed at the outer edges of the exhaust ports http://somender-singh.com/content/view/68/49/
http://www.somender-singh.com/ and the intake and transfers now have Powre Lynz grooving http://www.allpar.com/fix/holler/head-porting2.html

They do seem to work, engine does seem to be making a great deal more torque (lot more than I would expect from the small amount of bore increase) and the jetting is certainly running rich, even after a week of jetting down every other day the plugs were still wet and yet it was pulling 47 degree angle with the Shockwave.

Setup for 10000 ft was 18/45 gearing, Lite primary 100/260 with 7 weight washers giving 2850 RPM engagement and 7900 in 10000 ft powder and 8200 on trail at 9000 ft. Secondary Shockwave set at 47 degrees and Green spring about 180/303. It tractored off at 2850 engagement no problem, the high rate primary spring then snaps to full shift RPM with just a flick of the thumb.

I went down to the 100/260 spring as with 130/290 spring I was running out of room for weight washers back in winter 08 trip to CO. I started out this last trip with a 130/290 but felt it was trenching a bit with the 3150 engagement and I was right the 100/260 worked a bunch better.

I also put in a 1 degree flywheel timing advance key backwards for 1 degree retard.

Carbs have stock 08 needle and 3.5 clip postion was up to 1170 EGT in mids. ATAAC was baselined at 7800 ft and 77 % air Density, started mains off at 320 and got it down to 300's (only 1050 EGT) and plugs just barely starting to show a little black as they were still being washed pretty clean. Likely could go another 2 sizes down or more. I was being very easy on it as far as jetting as I had the Wisecos set at just over 4 thou which is pretty tight. Next time out will jet it down more as the pistons should be shrunk some.

I think the biggest performance increase the sled could use now would be if Camo made a 16 X 137 X 2.25 track that weighed about 47 lbs. It would really rock and roll then, the 1.75 paddles are likely holding it back a bit, has very good flotation because of light weight, about equal to a stock XP with around 16 X 150ish track

The new Caron fiber can and Alternative Impact Ti A-Arms could take another 11 lbs off the front end, very tempting!!!

Good Luck
 
#40 ·
Hey LRD,

Do you happen to have any pictures of the Singh Grooves you've cut into your head. I'm having trouble picturing where you've placed them.

Very interesting stuff you've done there. I'd love to hear some more of your insight into your engine mods, etc... I'm looking at building a sled similar to your but based on the 600 RS. Dmax makes a 770 off of the RS block with 800 HO jugs that looks very promising.

Also, have you considered moving to a 146" skid and track to get bigger lugs. Too much rotating mass perhaps? Anyways, keep the good info coming.

Thanks
 
#42 ·
You have great info but I would like to share with you some reseach I did on the 146" summit track.
If you order from ski-doo not same track as tracksusa it is rectangular ported and weights as much as a 136x1.25 the major advantage is the air is not trapped in tunnel and the skid is always empty. Not kind of empty but completely empty. On my 550 freestyle project with this track we ran 19/45 gearing with stock motor and were completely shock at performance. There are 2 choices in the 146" either the 600 carbed version which is 15" wide with 2"lugs or the 16" with 2.25" lugs. With your motor mods I would run larger track. Just my 2 cents hopefully it was worth that.
 
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