Supreme Tool Exhaust Valve Install on M7 ?s

[SnoPro753]

I installed my STM Valves on my M7 tonight and I have a few questions for those who have also done this.

Did you have very tight clearance between the valve and the radiator hose on top of the head? If so, any long term/high use problems with the two contacting each other?

When assembling the valves I installed the popup indicator pin with a spring on it? Is this correct?

When I installed the valve itself I put the 1/8 inch gap of the valve pointed down toward the crank, meaning larger beveled edge of valve facing the crank. Is this correct?

I currently have my secondary off the sled for other parts install and I started the sled up with the new valves and gave it some throttle. I saw the popup pin move but only ever so slightly. With the secondary installed and a load on the engine will the popup pin come out of the assembly more?

Any tips on dialing in the valves?

Thanks to Snowest in advance.

 

[clc900mc]

howdy, I love the stm valves and have bought them for both my mc's. what i have learned is that if you dont have the new titanium popup pins then they will wear out quickly (mine came with aluminum ones) I called stm and they said to just remove the pins and leave the springs in. anything touching anything in a high vibration environment will wear. the red caps that the springs fit in can move in and out to set where you want the valves to open. screwing the red plugs in will require more pressure from the engine to open them. I run a 900 mc and I leave them almost flush with the black cap, and they work great. you will just have to play with them a bit to see whats right for you. The guys at stm are great to talk to feel free to call them anytime.

 

[BigRed118]

Since these use Ski-Doo type technology, start with the red adjuster flush. That will be good for most applications. Question since I am interested in these valves, do you re-use your stock valve or do these come with new ones? The reason that I ask is I have porting and would have to send out the STM valves to get them matched. Do these get rid of the extreme lean mid range that the M8's are notorious for?

 

[SnoPro753]

Anyone with direct 2005 M7 experience with these valves?

 

[tatorsalad]

stm

I have them on my 06 m-7 and they work great the hose does hit i put some header wrap around the hose just zip tied it on there if you are above 5K i think the springs are to stiff and i run ski doo springs the 600ho springs seem to work the best for me if you are real high the 800 ski doo springs are softer yet. For the guy that has the porting they come ready to put in so you would need to grind them down just take out the galioin and grind it a little at a time put it back and check it.

 

[m8magicandmystery]

yep my directions say gap bottom m7...up m8..your spring is right...i set the red adj cap flush with inside surface black holder..approx 3/16 red cap showing above black cap..on the stand they flutter a bit opening..look at them under load in powder with the hood off they pop out strong like on viagra...maybee set opening approx 7000 rpm on stand..or as indicated above with red cap up 3/16...as long as the red caps are the same and they seem to open same time...its real hard to tell so dont let it bug ya...don;t think its an issue if a couple hundred rpm off from being syncronized..the adjust both the same as you feel ..and you will feel if your ok..you will know if they are opening late by just seat of pants feel...if you really want to get close just have and extra set of hands and with continuity light/beeper/meter have a friend hold one lead on plunger pop up and the other lead a specified reachable distance above (1/8 in) and watch tach and meter when circuit completes and repeat on other STM valve

 

[BigRed118]

So does it get rid of that nasty lean spot

 

[SnoPro753]

yep my directions say gap bottom m7...up m8..your spring is right...i set the red adj cap flush with inside surface black holder..approx 3/16 red cap showing above black cap..on the stand they flutter a bit opening..look at them under load in powder with the hood off they pop out strong like on viagra...maybee set opening approx 7000 rpm on stand..or as indicated above with red cap up 3/16...as long as the red caps are the same and they seem to open same time...its real hard to tell so dont let it bug ya...don;t think its an issue if a couple hundred rpm off from being syncronized..the adjust both the same as you feel ..and you will feel if your ok..you will know if they are opening late by just seat of pants feel...if you really want to get close just have and extra set of hands and with continuity light/beeper/meter have a friend hold one lead on plunger pop up and the other lead a specified reachable distance above (1/8 in) and watch tach and meter when circuit completes and repeat on other STM valve

Thank you very much. That is exactly what I needed.

What is your thoughts on different springs?

 

[m8magicandmystery]

Thank you very much. That is exactly what I needed.

What is your thoughts on different springs?

im fine with my springs..if i want them stiffer i would shim them..looser i would cut a bit...but they seem fine for me

 

[m8magicandmystery]

Since these use Ski-Doo type technology, start with the red adjuster flush. That will be good for most applications. Question since I am interested in these valves, do you re-use your stock valve or do these come with new ones? The reason that I ask is I have porting and would have to send out the STM valves to get them matched. Do these get rid of the extreme lean mid range that the M8's are notorious for?

wish i could tell ya on the mid range lean spot...i installed controller at same time as stms so the lean spot is gone and i have added fuel to mid range..i don,t know if the amount added would have been less with stock valves..my stms came with the valves..then Terra alps matched them to bigbore before sending up to me..

 

[SnoPro753]

Update

Just an update on the STM Valves. I rode at Snowy Range for four days with these valves and they rock. They aren't an absolute rocket over the stock valves but the midrange is awesome. They pop all the way open and the 700 rips. My 141 M7 can keep up with M8 153s. The last day I really adjusted them open and it worked awesome but I was afraid they were going to vibrate out of the valves.

I am going to go with the ski doo 600ho springs this year and move the adjustment screw down a ways. I don't think Supreme Tool makes them this way anymore. Now you have to take the valve apart to adjust it.

Overall, knowing that my cables aren't going to pop off the servo in the middle of the backcountry is worth the price twice over for me.