I believe the heat soak problem is the tmap sensor. Which is the air intake temp as well as the baro. The sensor on these kits does not reach into the direct air flow path so it cant read temp changes quick enough. It ends up reading the temp of the black silicone hose instead of the instant intake air temp. Ive confirmed this by cutting the little hose shorter that the tmap is in. My intake temps went up and down quickly all the time ( reading cooler and hotter, relevent to being part throttle and full throttle as one would expect). It also started really easy and idled perfect after being shut down for a couple min. I did this back in 2014 trying to find a fix before the goat 6 tune came out. When the goat 6 tune came out i added the exact length back to the hose so everything would be as silber designed it. Shortneing the hose is on one of the things to try again when i get out next.
2015 Silber Turbo Bog
- Thread starter Slednut84
- Start date
D
So did shortening the intake tube at the tmap sensor fix a bog on your 14? Sounds like a good idea. Anyone else try this yet?
I havent tried with the latest tune yet. On the first tune file silber used it did fix the bog that people are getting when riding right after firing up the sled from a heat soaked engine ( after being run and then shut off for several minutes). I get limited riding days so haven't been back out to try things for a few weeks now.
No it doesn't. I haven't noticed it taking any longer to warm up and it stabilizes quicker without it.
So after a lot of testing and troubleshooting, I have found the solution to the throttle bog in higher elevations.
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.
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 boondocks 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.
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.
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 boondocks 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.
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Thanks gsxr. After reading your response i believe we're over clutched. We're running 75.5 grams with a 165/310 spring in the primary at 7psi and 9-11k feet. The Silber vid recommends 75.5grams for 7psi at 6-9k feet which is lower than where we're riding (still would guess 75.5 grams is a bit much even for 7psi at 6-9k). I suspect we're loading the motor too much too early in the powerband causing the on off on throttle high rpm bog and the bog at low rpm just after engagement. We're going to try dropping some clutch weight and see how it performs this next weekend. Thinking of 72-73 grams. Does your sled feel under clutched running the 72gram weights at 10psi? Have you tried 74gram weights?
Still tbd on what's cause the off throttle bog at no load.
Still tbd on what's cause the off throttle bog at no load.
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Did some more riding today. Sled ran absolutly flawless. I was riding around 9500 ft. It probably could use a tad heaver clutch weight at that elevation, but I think 74's would be to heavy.
No bog issue at all with intense on/off throttle jabs.
Same prob
Out in the snowies for 1st trip today. Same issues. Went over the Handel bar many times. Prob did it 12 times. 80 miles on sled. It don't do it on start up. After riding for 20 min. Or so once ya let off an got back in it. Just like ya hit the kill switch, but keeps ideling. Work the throttle few times an it comes out of it. An runs awesome for quit awhile again?? Rpm fine, weights fine. ??? No idea what to try. Thanx for any advice
Out in the snowies for 1st trip today. Same issues. Went over the Handel bar many times. Prob did it 12 times. 80 miles on sled. It don't do it on start up. After riding for 20 min. Or so once ya let off an got back in it. Just like ya hit the kill switch, but keeps ideling. Work the throttle few times an it comes out of it. An runs awesome for quit awhile again?? Rpm fine, weights fine. ??? No idea what to try. Thanx for any advice
What boost, fuel, elevation and rider weight?
Was there any ice in you throttle safety switch? Do you have a tether?
10 lbs boost. 2 gal race gas no ice on throttle 9k 220 lbs
Steve. That sounds like a different issue
Like K said. Maybe throttle safety switch
Is icing up or something
The bog/stutter folks are talking about is only when
Hard on/off quick throttle movement
Your experiencing something else
Like K said. Maybe throttle safety switch
Is icing up or something
The bog/stutter folks are talking about is only when
Hard on/off quick throttle movement
Your experiencing something else
Steve are your spark plugs gapped to .020" and make sure there snug.
yes plugs are gapped. Guna try putting a 5# spring on turbo instead of the 10# might b to much @ that high of elevation with only couple gal of race gas!
K I'll get a 44 straight helix comin Don't think we weigh'd the weights but I think it was red red red on em any idea what that is for weight? thanks
Red is 3.5 grams, not sure if you have the 77 base weights?
After having very few issues with my sled other than the fairly consistent under load shutter, this weekend went to the 5 lb spring in my sled. Should have been running around 7 lbs of boost, honestly NEVER look.. didn't with the 7 lb spring either. Was out with another sled identical to mine with exact same kit with his still running the 7 lb spring. We swapped sleds for a bit and neither of us could tell much of a power difference between the two sleds.
Did help with the shutter, was only able to re-create that one time during the day... however, different snow conditions, temperatures, etc... having a base has helped performance for sure. My thoughts on the shutter was related to the sled dumping fuel in response to slight det sensor hits. Was always able to clear it out and didn't cost me much in terms of success on the hill. With the 5 lb spring, I was able to ride this sled exactly the same way I would a stock sled, WFO as often and as much as I'd like, didn't feel like that before.
You can see in the quick video below throttle response has been GREAT, really does run exactly the way I would have expected. Little lag and just great performance from a pump fuel kit. I have run race fuel in kits in the past and I was dead set on running a straight pump fuel kit on this sled.. everyone in my group has been impressed with the way the sled runs, super consistent, just a really fun sled to ride and on straight 91 fuel. Performs as solid as any pump fuel kit I've had (had 2 others on cats in the past) with a MUCH better bottom end performance from the external waste gate.
Quick video- sorry about the sound, hoping to update that today...
https://www.youtube.com/watch?v=hyPXyjdEAEQ
Also I literally haven't touch a THING, not clutching, not one thing other than the spring change this weekend. Sled is totally stock other than 36" kit and Dan Adams seat.
Did help with the shutter, was only able to re-create that one time during the day... however, different snow conditions, temperatures, etc... having a base has helped performance for sure. My thoughts on the shutter was related to the sled dumping fuel in response to slight det sensor hits. Was always able to clear it out and didn't cost me much in terms of success on the hill. With the 5 lb spring, I was able to ride this sled exactly the same way I would a stock sled, WFO as often and as much as I'd like, didn't feel like that before.
You can see in the quick video below throttle response has been GREAT, really does run exactly the way I would have expected. Little lag and just great performance from a pump fuel kit. I have run race fuel in kits in the past and I was dead set on running a straight pump fuel kit on this sled.. everyone in my group has been impressed with the way the sled runs, super consistent, just a really fun sled to ride and on straight 91 fuel. Performs as solid as any pump fuel kit I've had (had 2 others on cats in the past) with a MUCH better bottom end performance from the external waste gate.
Quick video- sorry about the sound, hoping to update that today...
https://www.youtube.com/watch?v=hyPXyjdEAEQ
Also I literally haven't touch a THING, not clutching, not one thing other than the spring change this weekend. Sled is totally stock other than 36" kit and Dan Adams seat.
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Just got back from riding. Tried a couple different thing. Put a 5# sping in turbo. ( still running little over 7#) an took a little weight out of clutch. Didn't put the helix in yet. But its a hole different machine. Don't have quite the power I did before but didn't have 1 hiccup. very fun to ride now. gota pull alittle more weight out of primary, only turning 7850. thanks steve
E
I did the same, put the 5lb spring in. Showed about 7.5 on the gauge. Ran 79.5 grams at 1500-4000 ft with an almond/red spring and silber clutch setup.
Less chop bog for sure. Had one takeoff bog that almost killed the sled. Weird, never did that, didnt do it again after that. Deep day, maybe snow in the exhaust.
Ran into a new problem. I went to make a really long climb in powder. At the top of this climb, i started getting what seemed like a missfire. I throttled back and turned out. Heat soak maybe? Im not sure.
I would say it ran better but I really missed the horsepower of the 7 lb spring (shows 9-10 on the gauge)
Less chop bog for sure. Had one takeoff bog that almost killed the sled. Weird, never did that, didnt do it again after that. Deep day, maybe snow in the exhaust.
Ran into a new problem. I went to make a really long climb in powder. At the top of this climb, i started getting what seemed like a missfire. I throttled back and turned out. Heat soak maybe? Im not sure.
I would say it ran better but I really missed the horsepower of the 7 lb spring (shows 9-10 on the gauge)
Has similar issues on 3 out of 4 15 external kits. 2 installed by Silber on brand new sleds, issues in under 100 miles. 1 with 1000ish miles installed by Silber. Mine started bogging bad with 30 miles, 10000ft 40av/60prem, 7lbs. Ran like a raped ape on the trail but as soon as a guys gets in soft snow it bogs bad when on and off the throttle. The fact that I only had the bog in soft snow and when the motor was having to really work made me believe it was clutching issues, but odd that it ran spot on for the first 30 miles, dont see any clutch parts wearing out in 30 miles either.
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