[BOOMER]

Hey guys I really need some help on my 98 mach z lt! last year I was running it stock with a 2x136 track it ran good but for where I ride I felt I needed more traction so I put a 2x151 and a set of JAWS PIPES on it and it runs awsome execpt for the top end. I have a purple, purple spring in the primary which is 160- 320 spring tension and I just rebuilt my secondary and put a new spring in it as well (beige spring) So all that is not stock is the primary spring, the pipes and the track I also dropped 1 tooth in my top gear. Now whats happening is that I pin it across the field and out of the hole it flys all the way to 70 M.P.H. at 8800 rpm then it starts to fall fairly fast right down to 8400rpm for the duration of the run. I have a straight 47 degree helix, what I'm thinking is to change that out for a double stage say a 48-44 what do you guys think??

 

[Krusty]

Sounds like a good place to start. What gearing are you runnung?

 

[dino]

Boomer: Try the stock 50-47 helix set at 18# and see what that does and post the results. Dino

 

[Sharkey]

You probably will never turn more than 95mph with a 2 inch long track. But hope you can make the thing pull strong to that point!

 

[ballsout1]

I dont have any experience with anything even close to a 2'' track but if your going through 4' of powder (as an example) that would seem to be similar to watercross, and those guys actually doo run real shallow helix`s maybe down to that 44 or 40 angle. Now, if your running that track in alot firmer stuff, I would first dial your preload up(if you find yourself going over  say 24 lbs stop) or maybe consider a spring more like a 230/380. You are running 286 ramps, I presume? ...... damn 2' track......are  you where they get snow?

?? My .75 is overkill right now...

 

[Mikadoo]

Just to let you know, your sled is designed to run @8300 rpm"s. 8800 is way out of your power band unless the jaws pipes were built to run it up there. Generaly you want your tach to pin say 8300 and hold it there all the way to the top but doo"s will slowly climb past that buy 2-300. If there is a cure for this I would like to here it.
From 99 to 02 the machz went down in spring pressure to a 200-290 [green-blue]and 295 ramps. I would say they must of got it right to finally stay with the same set up for 4 years. On my 00 I had to go to 18.7 pins to hold the rpm down on top. You have the same engine now with the jaws pipes so maybe this will help. I would also drop another gear [24]1.79 or even a 23[1.86]. I run a 1.76 ratio with my 136x1 1/2 and it works real well and still get 115mph out of it. With a 2"x151 I would have to say you would be lucky to hit 100 mph.

 

[BOOMER]

mikeadoo what gearing do you run? see it doesn't make sense because it was running great last year with a 136x2"and stock pipes. do you think that if I put the 295 ramps it would help and I have tried the 50 47 helix but it still did it but out of the hole was a bit better thats why I think that if I went to say a 50 44 or a 50 40 helix it would probably fix my situation and I finally bought a scale to see what pounds my secondary is set at and it is 19 pounds.its maby why they changed the clutching on the 99-00 models

 

[FIII_Mtn]

Boomer- can't help ya much with your triple tuning- I'm still working my way in that direction...

You *must* have rolled the case. There's no way 2" would fit with a 9 tooth driver in the stock location. ? I'm still working on getting all the rivets back in. Rolled the case back about 2". Gonna run 2x144.

 

[mach1]

you can try a 50-40 or 50 42 that will keep your rpm's up on shift out and you can go as low as a 50-36 from ski-doo.
I use a 50-36 or a 50-42 in my mach1 it seems to run it's best with those helixs  

 

[Mikadoo]

Boomer, I dont think changing ramps will help. I have both 286 and 295 and the only difference I can see between the two is at the beginning, from there on there the same.
I run 25-44 gears but like Flll mtn said you must have rolled the case to get 2" under there,I run 1.6 under mine with 1/4 clearance. I would try the gr.bu. spring like the 00-02 have the only problem with that is its the most expencive spring on doos list @ $37.95! You see you totally changed your power curve going to jaws pipes! Did"nt jaws give you new clutching spec"s?

 

[BOOMER]

hey guys mine is a factory long track that already is droped and rolled from what i was told but their is a .080 tunnel wich most sled are .060 so I'm not sure if the guy before me put it on or what.
I got my sled in at the shop right now their checking out why I'm burning so much oil, If I ride it hard up in the mountain I burn up to 2 1/2 litres to 1 tank of fuel so they are checking that out and then I'm going to order that 50-42 helix and try that. I think it will work just fine with that, it only makes sense .

I'LL let you guys know how I make out but thanks for all the replies.

 

[FIII_Mtn]

I baught the CK3 LT tunnel. The holes come out the same as the short track tunnel, with the only difference being that the front arm moves about 3/8 of an inch. A 2" would never fit. I tried mount a 1.75 before the roll. No way. Sotck tunnel is about .050. .080 has to be after market.

The rivets should tell the story. Stock tunnel has a recess for the SN/ID plate.

 

[BOOMER]

if thats the case then it is most likly a aftermarket tunnel and I have about 1.5" clearance from the track to the front of the tunnel

 

[FIII_Mtn]

Actually, on the CK3, the front of the tunnel has a lot of clearance. Well, more than the top, anyway. It's up in the top, right at the corner where the front of the coolers meet, that's the tight spot. I did my own roll, but didn't really drop much. Most of it was backwards. I now have about 4" from the front of the bulkhead to the drive wheels, and almost 3" to the top, at the tightest spot. Dropping down more and less backwards probably would have been better, but at the time, I really didn't want to relocate the jackshaft. The mount holes are amazingly close to the '01 summit skid mount holes.

 

[greygoat]

Hello Boomer
 I live just down the road from you near Red Deer,last year i bought a 98 Machz as a wreck and nursed it back to life.I also added Jaws pipes to it and there is quite a list of things you have to change as required by Jaws.The pipes run 8800-9000 rpm so you need the following set up, 286 ramps,threaded hollow pins with 2-3 set screws,green/pink spring 200-350,timing set to .083 b.t.d.c. change carb needle tubes to the o4 tube clip position 4. air screw 4 turns and finally a 44 helix. I know this sounds like alot to do but we did them and this sled is insane. The specs are not mine they are all Gregs at Jaws,and he claims 172 hp. and after running this sled i believe him,try it and you will see for yourself. This sled is also running k&n filters 430 jets all across although you are lower in Edmonton ,if you need any more info let me know and give you my e-mail adress,this sled also works awesome in the mountains just by jetting down,it hs a 141-2inch track.
                                  good luck Grey goat

 

[catscratchfevor]

Boomer,

  I have a friend that has the same sled with almost the same problem.  He found that he had a striped bolt on the rave valve.

 

[BOOMER]

hey grey goat happy to see someone on this site from the same province any way every one was a big help but you sound like you have pretty much the same machine as me what gears are you running I am running 24-44 and I think that is the majority of my problem and I am way down in jett sizes I'm at 270-270-270. but If you wouldn't mind give me your e-mail adress and we can talk some more or even you telephone number and with the problems I've bean having it would be cheaper to pay long distance than the last couple of repair bills I've had (and still they can't figure it out but I guess the can't really test run it to 70 m.p.h.) let me know I will call you or e-mail you

thanks ROB

 

[Mikadoo]

BOOMER, how do you get away with 270 jetting? You must be out west in the mountains? Mine was 310 stock but found at wide open throttle at 5 above she was a little lean! Went to 320 to keep it safe.

I ran with some bigger sleds last weekend and found I needed more gear so I take back what I said about 25-44 and now run 26-44 [gained about 5 sled]. I dont know why I gear every sled down only to go back stock!!!!
Also, if you want to run the same timing as 99-02 Mach"s it"s 0.102 BTDC, can be done with a laptop in 5 min"s!

 

[BOOMER]

hey guy remember when I said it was my secondary well it turns out that it was not. That it was all jetting I was down to 230 240 230 with jaws pipes which is the only thing that is not stock. what was happening is that I did not have enough fuel to create power on my top end so after all the clutch tunning I did, it didn't help at all except for the fact that it is done now is good though! so I put 280 290 280 in and took it for a ride and it was way better I gained 25 m.p.h on my top end and it hit 9000 r.p.m and stayed there so problem solved....... the worst thing you can do is totally trust a dealer they told me where to put my digitron probes and that I should run temps of 1260-1280 degrees so I kept jetting down I am so suprised that I never melted down at all,when I was up in the mountains I rode it hard and I was hitting temps of 1380 so I never even would of thought of jetting the other way  

but again guy thank you for all your replies it totally helped.........

 

[greygoat]

Boomer
 Try [email protected] ask for Steve
                             Goat