why the f is my mcx apex popping

[Jona$]

I feel kind of lost now what to do, a primary spring I guess but more or the same preload? 35kg more or less totall force? 118kg and what angle on the shockwave, 45? I run straight since that was the recommendation I got for climbing and that progressive would be to heavy. Also a new helix would cost me to much at this point.

 

[Jona$]

Well talked to Ntc here in Sweden, a well known Company for turbo sleds, he recommended silver green silver or green green green to get it to bite the belt and get a fixed helix 43 since they were not that satisified with shockwave.

I ordered the ggg , then will see what rpm I will see , i didnt order the 43 helix since i want to be able to go higher in number if the 2gr extra i have for the weights wont be enough to hold down the rpm.

I also ordered the dalton red secondary if the first part dont work out for me. but what are the spec for dalton red.

Or do you guys believe the 51/43 will work with the new primary spring, i remembered rxrider likes the multiangle but cant se any longer sled use them.

 

[rxrider]

With that super stiff AC secondary you have serious slippage in the primary.
I run the Dalton Red secondary With 56/46 helix.

 

[Jona$]

RX RIDER:
As said, i ordered the red Dalton for secondary.

Im also curious how come you recomend 54/44 helix and not a straight example 43,44 or 45?

As you all know i run a 144 with 2" paddle. I run quite alot trail and the sides of it, but when i can i hit the hills and deep snow.

And as i been told a multihelix dont work well there?

Also i get a high number in the start will hold down the rev so it wont hit revlimiter on wot but wont it also give the primary a harder time to grip the belt, because lower number better sideforce right?


KVIPER:

wow 56/44 steep start what track are you running and what enviroment.

Also what sec spring are you running and setting. I ordered up ggg primary spring 40kg-131 and the red secondary spring from dalton.

PS. I still got the 51/43 if that would be a better fit if going for multiangle.

 

[Jona$]

Guys?

 

[rxrider]

If you can keep it off the rev limiter run a straight helix.
I can't, that's why I run a 56/46 Helix.
My track is 144 x 1.5 and I run 25/38 gearing.
Power is 350 HP.

 

[kviper]

I run a 128" x 1.25", the driven spring is from a friend and he won't even give me the spec's on it.
When you run a shallow cam it makes the driven clutch more torque sensitive under load. That means it's trying harder under load to close the driven clutch (shift down). So you need a lot of weight in the primary to keep it shifting up = a lot of load on the belt as rxrider said, probably the reason you are blowing belt's.
I would go to a 56/44 or so than start pulling weight to get the WOT shift RPM you want. Monitor clutch temp and control backshift and
Clutch temp with driven spring and wind. Probably will need a pretty good spring though.

 

[Jona$]

Well after reading your answers and ty tech corner, a straight helix seems to works best for me and tuning.

I'm just gonna throw in the Dalton red at 6-2 instead of arctic green and the new ggg 40-131 instead of ysy 35-118 primary and see were the rpm will land and the temp on the sheaves, and go from 42 to max 45-46 on the shockwave helix, if I need to get down rpm more then that i should get a progressive 54/44 for example. Since already having 83gr total weight.
Does that someone about out right?

 

[Jona$]

also float or fixed sheave, i hear both 15 18.5 depending on messure..

 

[rxrider]

I would leave the secondary floating, 2-3 mm free play on the spline is the spec.
Keep the off-set as Close to 15 mm as possible. Spec is 13.5-16.5 millimeter if I remember it correctly.
And the most important is the alignment of the primary and secondary sheaves aka the parallellity of the engine and the drive shaft.

 

[Jona$]

was just the paralellity i was thinking on if locking it, some people seem to believe it cant align correct under load with float. causing heat and wear.

My float settings are up to spec.

 

[rxrider]

Well..... Ski-Doo have run locked secondary for ages and they blow belts. I just don't buy that one, that you need a locked Down secondary.
The engine has to be in Perfect alignment With the secondary shaft.
This has to be checked every season at least once on a turboed sled.

 

[ghost rider]

Holy sh this gets very complicated.... I was thinking of up grading my clutch parts but now I just feel lost after reading this thread.
Touché to whoever fixes this problem!
Sorry to barge in......

Barry

 

[Jona$]

picking up the ggg primary today, dalton red is in the secondary at 44 deg 6-2.
Marked both sheaves with pen to see that it shifts full out. also a ir tempgauge in the pocket.

So im ready for setup in the weekend.

No worries Ghost rider, go for it.

when you say alignment rxrider i assume you mean offset since the enginemounts are solid on apex.
'
If not, whats the c-c numbers.267.5 mm ?

 

[rxrider]

No problems ghost rider

No they are not solid, but they are adjustable.
Both in the front and the rear of the engine.