Silber ECM Flash High elevation BOG FIX!!!

gsxr1k2 · Jan 9, 2016

So after a lot of testing and troubleshooting, I have found the solution to the throttle bog in higher elevations (on/off throttle jabs boon docking and heavy load throttle re entry).

First and foremost. Make sure your power valves are clean!! This is a must. Also check the lines going to the solenoid. Make sure the plastic fitting is snug and not leaking on the inlet side.

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Second. I currently run the external waste gate, reflashed ecm setup with a 10 psi spring. I run around 9500-11,500 ft.

I have found that a pink primary spring (team 180-320), 10-72 weights, 44 straight helix works outstanding. I have found running a reverse split helix seems to build to much belt heat and shifts to much. This clutching setup WILL ELIMINATE the on/off throttle bog @ 10+psi, 9500-11,500 ft.

For those of you running lower boost and elevation, I would recommend starting with 10-74's.

The sled is extremely sesitive to clutch weight.

People need to keep in mind that a turbo charged two stroke motor is a difficult engine to keep happy 100% of the time and will occasionally "fart, blurp and stutter". I have a 2015 all out built VOHK pro, 2x aerocharger kits, 3x boondocker kits and one Silber setup. THEY ALL HAVE THERE QUIRKS.

This Silber sled is by far the best running kit I have. If anyone has issues's PM me and I can most likely help. I also have a shop in Casper, Wy and make lots of trips to Togwotee/Snowy Range.

wellfed777 · Jan 9, 2016

gsxr thank you for your post

a couple Qs

are you saying run polaris 72g weights or the Team rooster turbo weights that come with the kit at 72g ?

are you also running a different helix than the kit one
or running the kit helix on the 44 setting
(sorry i can't remember what helix silver sends i thought it was a 44)

i hope that makes sense

gsxr1k2 · Jan 9, 2016

I'm using the Polaris 10 series weights. I'm not sure what Justin is sending out for a helix. I prefer the straight helix and the sled reacts well with it.

B2 · Jan 9, 2016

What secondary spring are you running with the straight 44 helix? I don't have a Silber kit but messing with turbo clutching. Thx!

sledhead9825 · Jan 9, 2016

People need to keep in mind that a turbo charged two stroke motor is a difficult engine to keep happy 100% of the time and will occasionally "fart, blurp and stutter". I have a 2015 all out built VOHK pro, 2x aerocharger kits, 3x boondocker kits and one Silber setup. THEY ALL HAVE THERE QUIRKS.

Well I disagree. 3rd season on my 2013 Boost-it Ho Pro at 8lbs pushing a 174x3 and I have 10 days in this year so far. So I ride a bunch. It runs perfect all the time, pull rope and go. Have never adjusted the fuel box in three years .I change spark plugs once a year until this year, going to change them tomorrow for this season. Never cleaned the power valves (Legends oil) I really should. Original pistons and the engine has never been apart other than adding a PAR head when the sled was built.
The only things that have let me down on the sled.
The factory exhaust sensor bung cracked around the weld.
Broke a Primary spring and the fuel pump starting drawing to much amperage putting on my Battery and check engine light.
The sled goes on all rides. Revy, Whistler across the ice field Hurley backcountry everywhere my buddies go on there new stockers I go (only faster). There are some other members on here that know my sled, been on rides with my sled and have ridden my sled. They will all tell you the same thing.
On top of all that it is fast, power delivery is smooth and NEVER burps spurts goats misses.
How many threads do you see on here guys talking about ill running Boost-it sleds ?

wellfed777 · Jan 10, 2016

umm sir are you helping the thread about Silber issues

NO !

i'm glad your kit works perfect but give us a dam brake
and chime on if you have a helpful tip about the actual kit or problem we're discussing

GEEEZ :face-icon-small-dis

:focus:

kanedog · Jan 10, 2016

Well, I disagree also. If it's a 2013 sled and you have had it for 3 seasons it isn't exactly how it sounds. 1st season you may have put on some miles. 2nd season was last year which was a no snow year and if you rode, it wasn't any hardcore riding or powder. This year, you have 10 rides. Hardly a season.
Sounds like for the amount of riding you have done the sled has given you a fair amount of issues. Not knocking Polaris or the turbo manufacture, just pointing out the obvious.
I'd also like to point out that if you don't start maintaining your sled a bit better, it's gonna give u way more issues.

Boston Racing · Jan 10, 2016

Some of your finding are interesting. I agree that poweevalves need to be clean but am having trouble grasping the helix angle causing belt slipping. If you are running a straight 44 how would that cause less slippage that the 44/48 that comes with the kit. Is your thought that the belt is skipping while transitioning to the 48 degree angle. I'm certainly not a clutch expert and am just trying to understand your thought process.

What RPMs are you running with the 10-72s?

sledhead9825 · Jan 10, 2016

wellfed777 said:
umm sir are you helping the thread about Silber issues

NO !

i'm glad your kit works perfect but give us a dam brake
and chime on if you have a helpful tip about the actual kit or problem we're discussing

GEEEZ :face-icon-small-dis

:focus:

I responded to gsxr saying all 2 stroke turbo sleds have Quirks or less than perfect tunes.
Saying they all have Quirks is not fair to say. I don't have running issues. Not going to voice my opinion on what your running issues might be because I have no idea.
Hope you figure it out the running issues, nothing worse than getting out on the hill and its missing and goating.

Kanedog
A primary spring, a cracked weld and a fuel pump are a lot of problems?
Well been sledding along time and feel pretty fortunate with that few issues no matter what sled it is.
Agree with the maintenance, its getting some love this week.

Silber boys, not my intention to get off topic. Good luck

gsxr1k2 · Jan 10, 2016

Boston Racing said:
Some of your finding are interesting. I agree that poweevalves need to be clean but am having trouble grasping the helix angle causing belt slipping. If you are running a straight 44 how would that cause less slippage that the 44/48 that comes with the kit. Is your thought that the belt is skipping while transitioning to the 48 degree angle. I'm certainly not a clutch expert and am just trying to understand your thought process.

What RPMs are you running with the 10-72s?

"The helix angle basically determines how quickly the secondary opens and closes. A straight cut helix (let's say 36 degrees) opens and closes the sheaves at a constant rate.

A progressive helix typically has the larger number (steeper angle) first (but sometimes it's reversed) say a 44/36 helix. The steeper the angle the more load you put on your engine. You can load your engine via the primary clutch AND the secondary clutch. So, the advantage of a progressive helix is the steeper angle loads your engine very quickly and allows your sled to accelerate more quickly while it's still in the meat of its powerband.

The "progressive" means you may start at 44 degrees but, your helix angle is gradually decreasing down to 36 degrees in this case so you can still have a good backshift. Some helixes aren't progressive and have more or less a "step" between your 44 and 36 degree angles. They aren't used as widely, especially for the mountains where you end up stuck on the step between the two angles at the most inopportune time. Straight cut helixes are often prefered by mountain riders due to their consistant shift rate. This is where I believe a lot of the belt heat and failure comes in.

The "backshift" I speak of is best illustrated by the thinking of climbing a hill. You are going pretty good up a mountain and there's a snow covered log across the hill diagonally so you have to slow down. The backshift is showcased right after you slow down and want to hammer the throttle again. You want your helix and secondary spring combination to shift you back to a lower gear quickly so the sled accelerates quickly again without a bog.

High initial angle helixes with lower finish angles are great for drag racing where your motor is loaded quickly but, the helix drops to a lower angle after your sled reaches the limits of its low end grunt and allows it shift out for higher top speeds. They also CAN work in the mountains but, the machining of the inital angle may be abbreviated to ensure you are on the straight cut portion of the helix for the vast majority of your up and down adventures."-Frostbite

I stole the above from a member on here that could explain it better then I could.

I'm turning around 8150-8300, 10 psi spring from 9500-11,500 elevation.

gsxr1k2 · Jan 10, 2016

sledhead9825 said:
I responded to gsxr saying all 2 stroke turbo sleds have Quirks or less than perfect tunes.
Saying they all have Quirks is not fair to say. I don't have running issues. Not going to voice my opinion on what your running issues might be because I have no idea.
Hope you figure it out the running issues, nothing worse than getting out on the hill and its missing and goating.

sledhead9825 said:

No offense taken.

Today I was able to first hand ride and watch the new TSS kit for the Axys run. So that makes 5 different kits I have had first hand experience with and on many unique sleds. I still stand behind my comments as posted above.

I HAVE YET TO EVER!! EVER! RIDE A TWO STROKE SNOMOBILE THAT RODE AS WHAT I WOULD CALL "FACTORY QUALITY". (I.E. running like my power stroke diesel every day, day in-day out.)

Click to expand...

kgra · Jan 11, 2016

Some more info on clutching

Strait helix is most consistent. Tapered helix can increase peformace as it acts like a steady shift of gears. The dual angle can cause catch points. All have thier uses.
Higher angle helix means quicker accelartion, provided enough hp is available. It also sets boost quicker on turbo sleds because more angle means more load.
Naturally aspirated engines usually run a higher angle start and lower angle finnish. This is because na motors generaly have more bottom end power. And not enough hp to keep the sled accellerating at higher speeds.
Turbos generally work best with strait cut helix and tapered helix with lower angle start and higher angle finnish. The lower angle start is more important with larger turbos due to the needed rpm and air flow to start the turbo spooling.
Too low of helix angle will make your sled loose ability to accelerate when under heavy load, instead the engine will easily get to full rpm and hold there. This is how work sleds like a skandic work. Great for towing.
Sleds with too high of helix angle will cause the sled to not accellerate through the rpm band.
Higher angle helix is generally used for hard snow racing and lower angles in deep snow to achieve the best accelleration and performance.
Backshift is also important. Higher angle creates slower backshift. Backshift is a geardown that occurs after letting off throttle and getting back into it. A 300 -500rpm drop that corrects to full rpm within a second is acceptable.

The 44 helix will help with bog. For 10psi at 11000 feet not too much performance will be lost but in a race in any snow condition id bet a 46 will be faster and hold more track speed during climbs. For 10psi at 5500feet ( where i generally ride) going from a 48 or 50 helix to a 44 creates a huge loss in performance. Track speed during a climb is almost 10mph less. The hp of 10psi at 5500feet is equivalent to approximately 13psi at 11000feet. If someone is addiment on trying to better this problem with clutching id recommend trying the gold team primary spring which has a higher finnish rate, if your using the pink one currently. It should increasepeak rpm approx 150-200 with no change on engagement rpm if your trying to increase or hold peak rpm while in and out of throttle. It should last longer as frequencies will vary more during compressions due to a larger range between start and finnish rate. But lt will require more weight in the mid and or tip of primary weights if your not wanting to increase peak rpm, in which case slows backshift. The higher finnish rate will create quicker backshift with less sacrifice to performance than using compared to using too low of helix. So recommend only if your after more peak rpm and backshift.

Note that cvt clutching has so many variables, hense the reason i used "generally" or "should" a lot.

revrider07 · Jan 11, 2016

I'm with kgra on this hard to test top performance unless using test sled side by side comparison cvts options are endless to get same results but key is to find one that works in the conditions YOU ride in. I'm for making most track speed and go from there to fix this issue.

kgra · Jan 16, 2016

kgra said:
Strait helix is most consistent. Tapered helix can increase peformace as it acts like a steady shift of gears. The dual angle can cause catch points. All have thier uses.
Higher angle helix means quicker accelartion, provided enough hp is available. It also sets boost quicker on turbo sleds because more angle means more load.
Naturally aspirated engines usually run a higher angle start and lower angle finnish. This is because na motors generaly have more bottom end power. And not enough hp to keep the sled accellerating at higher speeds.
Turbos generally work best with strait cut helix and tapered helix with lower angle start and higher angle finnish. The lower angle start is more important with larger turbos due to the needed rpm and air flow to start the turbo spooling.
Too low of helix angle will make your sled loose ability to accelerate when under heavy load, instead the engine will easily get to full rpm and hold there. This is how work sleds like a skandic work. Great for towing.
Sleds with too high of helix angle will cause the sled to not accellerate through the rpm band.
Higher angle helix is generally used for hard snow racing and lower angles in deep snow to achieve the best accelleration and performance.
Backshift is also important. Higher angle creates slower backshift. Backshift is a geardown that occurs after letting off throttle and getting back into it. A 300 -500rpm drop that corrects to full rpm within a second is acceptable.

The 44 helix will help with bog. For 10psi at 11000 feet not too much performance will be lost but in a race in any snow condition id bet a 46 will be faster and hold more track speed during climbs. For 10psi at 5500feet ( where i generally ride) going from a 48 or 50 helix to a 44 creates a huge loss in performance. Track speed during a climb is almost 10mph less. The hp of 10psi at 5500feet is equivalent to approximately 13psi at 11000feet. If someone is addiment on trying to better this problem with clutching id recommend trying the gold team primary spring which has a higher finnish rate, if your using the pink one currently. It should increasepeak rpm approx 150-200 with no change on engagement rpm if your trying to increase or hold peak rpm while in and out of throttle. It should last longer as frequencies will vary more during compressions due to a larger range between start and finnish rate. But lt will require more weight in the mid and or tip of primary weights if your not wanting to increase peak rpm, in which case slows backshift. The higher finnish rate will create quicker backshift with less sacrifice to performance than using compared to using too low of helix. So recommend only if your after more peak rpm and backshift.

Note that cvt clutching has so many variables, hense the reason i used "generally" or "should" a lot.

Sorry guys i was thinking about what i wrote in here and come back to check it cause i realized i wasnt clear enough on describing what i was recommending the gold spring for. So i edited it.

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Silber ECM Flash High elevation BOG FIX!!!

gsxr1k2

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wellfed777

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gsxr1k2

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B2

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sledhead9825

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wellfed777

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kanedog

Undefeated mountain clutching champ of the world.

Boston Racing

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sledhead9825

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gsxr1k2

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gsxr1k2

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kgra

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revrider07

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kgra

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