The infamous powder bog

if you grab your plug cap with one hand on the plastic part where the wire threads in, and the other on the rubber part that does a 90 degree bend and pull back and forth. one of my caps had play in it, the others didnt, changed that cap and it was great after that. cut the old cap apart for fun, it was full of black soot, theres a spring in there that pushes on a pin, the spring was all loose and from what i see wasnt making contact all the time.
Pat
 

Just got back from some DEEP snow riding today! So much snow piled up on the hood, couldn't even tell what color it was!! The additional holes in the cowl worked great, no bog.

Bill
 
Ok I have to ask, a inch to the front of the exhaust pipe?
are you say to the end sticking thru the bellypan? if so did you cut at a angle then to let the exhaust escape out toward the rear?
 
deeppowder said:
I have a 98 MM 700 and when the exhaust was stock it never bogged. Put on a Bender can and it never bogged. Put on Bender triples last year and it started to bog, but only when sidehilling to the right. I figured it was the pipe outlets jamming with snow so I installed a bigger exhaust deflector. I haven't had any trouble since (yet).


I used to own a piped viper and a stock viper (still have the stock one). Took both in deep snow in the same conditions. Piped unit bogged, stock unit ran great. Don't know if this helps, but I have seen it first hand.
 
I am working on this right now. I will let you know as soon as I figure it out. Drives me insane also 3 new feet of powder the other day. Would have been nice to not bog.
 
Well the exhaust deflector did nothing, I was also in 3 ft of fresh fluff this weekend. At one point when I was burried in snow, It was bogging so bad I couldnt even get the rrrs up to engage the clutch so I opened one side of my hood and lifted it up, then VROOM up it went. My new conclusion, the exhaust pipes are getting plugged by the deep snow, and the exhaust gas is leaking out at the manifold, so IM gonna re seal them , extend the stock deflector some more and try it again!!
 
I had this problem a lot in my old Viper ER, as did my son on his Viper and it only occurred out in the deep snow when we would go out west - Montana. It was definitely plugging of the "ram-air" vents. We both would have to stop every so often and clean them out when it started to bog. I solved it with some pre-filters on those intake vents on the windshield cowl and some powder filters cut into the dash (I only used two of the four). No problems in deep snow since then. Also, a prefilter over the airbox. Both machines did it, my son's Viper is triple-piped.

They sell those at Mountain Performance. Look here, and scroll about halfway down. The filters on the intake vents of the cowl were a little bit of a PITA, but they looked great and worked well.
 
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..SNAKEBIT.. said:
02 Viper 144 x 16 X 2" paddle
CPR pipes, with head mod
Yamaha exhaust deflector
8ek no rivets stk spring
43' helix silver spring 90' (plus) twist I think
21 top 41 bottom gearing 70L(maybe going deeper?19/41? or 19/38)
8 tooth drivers (extroverts)
holtman Atacc installed
jets 162.5 162.5 165
pilots 47.5 47.5 47.5
needles 3th groove washer top & bottom
fuel screws 1.75 1.75 1.75
all stock carb parts
2 flo-rites, ram air filters, air box prefilter, 1-1/2" hole drilled in each ram air duct to dump air right into the air box
all under air inlet to air box are duct taped off, to suck only outside cool air, from ram air and flo-rites
and still tuning LOL
LET ME KNOW WHAT CURES THE BOG!
Headed West most likely the end of the month any more ideals?
I think I am going to switch the plug boots and make the deflector longer?
also thinking of drilling holes like HAMMER did (Hartman's Viper)
 
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..SNAKEBIT.. said:
Headed West most likely the end of the month any more ideals?
I think I am going to switch the plug boots and make the deflector longer?
also thinking of drilling holes like HAMMER did (Hartman's Viper)


I talked to hartman, and he also said to tape the whole headlight assy off on the inside, I got in mine and looked at it, air can definiteley come in from there and put dirty air in the air box. Im pretty sure that the cause, dirty air = crap running....
 
Well, sorry I haven't been able to do any good testing yet. I finally went out for the first time last Sunday. There was powder, but not the dry, light kind that seems to make my sled bog really bad. I only got one bog all day, I was side-hilling on the left side and the ski threw a wad of snow onto my front vents. It bogged slightly and then recovered immediately. Just not the right kind of snow to test in.

Coming back, I noticed that my gauge pod shuts off & then comes back on when I change between high and low beam, and also when I hit the brake. Looks like the notorious harness rub through has struck, :o| so now I'll be draining and pulling the gas tank off on Friday. Pretty sure that's where I'll find the problem since the brake is involved, but I might as well pull the pipes and put the one under the motor in a wire loom also.
 
OK guys well im going riding sunday and monday, so Ill have another report for you.. as of right now the last time I rode( last sunday) I had a horrible bog.. SO since then I have resealed all my pipes and the mounts, put on 02 viper ram air intakes, taped the hood off so it only can get air from the flowrites on the dash, I have built a new exhaust seal for the belly pan where my tripple pipes come out so no old air can sneak back into the engine compartment, and I replaced and sealed my spark plug caps.. Ohhh this better work now!
 
My 2 cents

I have read this thread closely and I also am a member of the infamous powder bog.

I got the bog in yet another situation that so far no one else has mentioned.

That is when I go up a steep hill and come running with the skiis way up in the air and only on the last turning wheel (sorry for my bad english explanation). Then my sled bogs slightly at first and when the nose slams down in the pow i bogs hugely and it takes 3-4 seconds to recover.

I am almost a 100% sure it is because the pow hits the pipes from the vents in the nose that cools down the pipes and therefore it bogs heavily! A also agree to that it bogs when you stop in the pow and the outlet from the pipes gets blocked. Have tried it carefully and the bogging is there every time the outlet is blocked totally by snow. Even only for a few seconds and when the blocking is gone it rips again. And I do have the stock deflector in front of the outlet, but in the deep pow it does not make any difference if you let the rpms down to low.

Therefore I will block my front intakes from letting pow hit my hot pipes in the very front of the sled. I will get back with a report after this weekend, since I think I am going our riding if someone is interested in the results.

//Rob
 
Thanks A K for the link to this thread.
I've been fighting this bog for some time. When I had a pre filter on the box I could open the hood and watch as it went up and down from the suction created. I've drilled the dash like hartman and made prefilters to go over it. The filters get snow on them then it turns to water and plugs them up.When in deep powder my dash seems to be covered in snow all the time. I'm going to build a cage to put on the dash under the prefilter to give it more surface area and see if that helps. I'l let you know after this weekend As it looks like we'll have some more powder again.
 
Maxeater, we'll probably never have powder like last weekend again. Passed you on the trail, Mountain Vector and a bunch of AC's Island park area.
 


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