[Polishboy6426]

I acquired this sled for next to nothing, has slight modifications done to it like stingers and slight clutch work (I don’t know what but it’s not stock because of the purple helix) air box removed and k&n pods installed, assuming the jetting was changed. The motor runs strong however know clue how many miles. I’d like to do a complete rebuild on this sled. Big bore kit, timing key bigger carb, reeds, aftermarket pipes, clutch work, etc. Now I know there used to be kits by d&d, black magic, bikeman, and others, however I don’t Believe these companies manufacture these pets anymore. What would be my best route of find pets for this job? Any suggestions on what I should do to it? I live on the Saginaw bay and that’s all this sled will see is straight line ice running, I’m not crazy about number or anything I just want the sled faster than it is now. All help is appreciated for I have researched this for 2 weeks now but everything I read is from 10 years ago when these companies still manufactured parts for these sleds.

 

[tcat446]

Hard to find pipes for them and if you do and they happen to be new you will pay dearly. Let me know what you have for springs weights helix and gears. I may be able to help you.

 

[Polishboy6426]

Are numbers stamped on the helix and weights? The primary spring is all hello and the secondary is a dark color can’t really tell what it is, the secondary helix is purple, I can get numbers for you if they are stamp on there

 

[tcat446]

Yes, numbers on helix and weights. Primary may be a Yellow white stripe spring. Got a pic of the secondary spring? Do you know if the gears have been changed. Just went thru all this with my ZRT 6.

 

[Polishboy6426]

Nothing to my knowledge has been done to the gears, what is the stock tooth count? I’ll be able to get some pictures tomorrow

 

[Polishboy6426]

are Stock zrt 800 carbs the right way to go if I go with a 700cc over bore kit, if I can find one. All I’m finding is a 69mm bore kit putting it around 640cc from wiseco

 

[tcat446]

Nothing to my knowledge has been done to the gears, what is the stock tooth count? I’ll be able to get some pictures tomorrow

23/40 is stock for under 5000 ft. altitude.

 

[tcat446]

Don't know how much you plan on spending, but if you do find a kit it will cost a lot. Your likely better off clutching and gearing it. You can do a few things to make the stock 600cc run better but not like a kit. Your call. You can lift cylinders, cut the heads to compensate for the lift, reeds, port case and cylinders and pipe it. I would forget boring the carbs or using 38mm unless you lift the cylinders. If you go with a kit you will want the 38mm or if it was me, the 39.2 bored carbs.

The old D&D 700 big bore kits were called Thundercat killers to 100 MPH. A buddy had one and I can tell ya first hand that is accurate info.
The first thing you need to do is figure if you want to run a stock 600 with mods or spend money on something else and go from there.

 

[Polishboy6426]

As much as id like to get a 700cc bore kit, I can’t find one anywhere, biggest I can find is a 67.5 mm bore kit from wiseco, putting it at 612 cc, which is t what I want but at 23 years since that sled has been made I’m not surprised companies quit making them. So if I went with this 612 cc route, stock carb will be fine with proper jetting? Can I still run v force reeds like I planned?

 

[Polishboy6426]

i did some calculating and what I can gather is the bore size for the old 700cc kits was 72 mm, stock zrt 800 bore is 72mm, will a stock zrt 800 piston go on a zrt 600 rod? I could but a gasket kit for a 600 and pistons for an 800

 

[Polishboy6426]

I’ve decided to say piss on the 700cc idea and go with the 612cc bore kit since that’s what’s available with it being such an old sled. So with that, I got my hands on a set of aftermarket pipes (brand I don’t know). What should I do with the rest to get the most out of it? What helix springs and weights? I’m assuming keep the stock carb but rebuild it and figure out the jetting, v force reeds? What gears in the case? Is a timing key worth it?

 

[tcat446]

For the difference in cc the 612 is a waste of money. I think stock was 598cc. Your better off porting and clutching it and be happy with that. As for pipes, you need to know what they are so you know what rpm to spin them at. Timing key if trail riden is a waste. One bad tank of gas at a trail side station and your done most times. Not worth the gain a key will make in my opinion. If you port the engine you can run 38mm otherwise stick to the 36's that come stock on it.

 

[Polishboy6426]

Went and looked at the clutches and the pipes. First picture is primary which appears to be an orange spring and it has 10/M5 weights. Second picture is secondary which appears to be a black spring with a RPC1 helix which I believe is 57/38 from what I’ve read. Third picture is the pipes, I could not find anything stamped on them whatsoever to tell whether they are stock or aftermarket.

 

[Jaysittinback]

I agree with tcat446 especially about timing.
I'd build on its strengths, high rpm power. Stack up the jugs, plane the head to match, carbs perfectly in sync, balanced, best clutch settings. All cheap or free stuff.
Find cheap used flatslide 38's off a machZ or Panterra... flats have better venturi and won't give a bog like big old round 38's.

 

[Polishboy6426]

So is this clutch set up this sled has already okay for this sled? 0range/white primary spring 143/290 with 10/M5 49.5 gram weights, rcp1 58/53 helix with black secondary spring which I believe is 42 lbs

 

[Polishboy6426]

And can anyone tell if those are stock pipes or not?

 

[tcat446]

Those are not stock pipes. With the weights in that I am thinking they want that to spin 9200 rpms. Most aftermarket pipes for tht 600 are targeted at that rpm. If it turns 9200 at wide open throttle then its right. You will have to drive it and see.

 

[Polishboy6426]

Once we get more snow I’ll be able to take it for a ride, ****ty winter here in Michigan. Does that 42lbs spring sound right for the secondary? Seems awefilly damn light compared to what others run

 

[tcat446]

I would agree with that. I would try getting a purple D&D secondary and see what that gives you. That's 83/140. A Cat red/wht is close and a little softer at 116 if you have one. We have always had better luck with the purple though on the 600's. That spring in there may be a D&D black which is 57/106. Once painted without specific markings or numbers you don't know what you have or who's it is. You do realize all black springs are not the same rate right?

 

[Polishboy6426]

I know they arnt all the same weight but it has an ac primary spring so I kind of assumed the secondary was probably an ac spring. So for the 58/37 helix ( I know in one comment I accidentally said 58/53) is this an alright clutch for this sled? from what I’ve researched most gues use like a 58/53 or something close to it, is it worth changing? And this may be a stupid question but I’m new to this, are all these other helix’s guys try stock helix’s from other arctic cat models?