Piped Viper question ?

My bad, meant to mention I didn't do the air box mod. I am going to do the TPI valves one of these days though. I didn't want to chop my airbox up.

I read Olav Aaens book on carb tuning. That was why I went with the 170s. Had I not read that I would have started with the 165s. I liked the thought of starting out very rich.

Yours really sounds like it is way lean from everything I have read. What I have learned already though;

First and foremost, always easier to correct from too rich. Too lean and it may be too late.

The starter circuit can be used to test for a too lean condition. If you think your too lean in one area, test it with the starter circuit part way on. If it clears it up you at least know what you have to do to fix it.

I think it a good time to mention again, if you start out too lean and keep testing it may be too late.

I also learned that new plugs are very hard to read. They need some time on them before they color very well.

did I mention that too lean and it may be too late?

MrViper700 has been very helpful. He laid out the testing sequence for me in another post. He laid it out in very simple terms and very easy to accomplish; (the screws was for a specific issue I had, rich at idle)

mrviper700 said:
turn the screws in first, if you get to about .50-.75 turns out total then I would jump down in pilotjet size, the fuel screws usual area or operation is 1 turn to 2 turns out.

run the sled at idle, and very low speeds, then whack the throttle from a dead stop, does it bog or rev up nicely? after idling are the plugs fairly dry/ if yes then your ok on the pilot jets and fuel screw settings

then run the sled at half throttle for a small stretch keeping it at half throttle, a good 350ft at least, shut it off and pull the spark plugs, should be nice and dry, light brown and good wash on pistons. adjust clip up or down to compensate.

finally take the sled out again and run at least 500-750ft at wide open throttle, do the same plug and piston wash checks and adjust your main jet size to suit color/wash.
Click to expand...

White plugs are a very bad thing BTW. It speaks to a lean condition just prior to melt down from what I understand.
 

Well I took the Viper out a few days ago for some test runs .
That thing pulls like its strapped to the space shuttle !
I did a few chops at 1/4 throttle and the plugs were still brown , the very end of the ground thing on the plug was a dryish tan going to black closer to the threads . The PTO plug was iffy , half of the electrode was brown and the other half was tan . I took a few 1/4 to 3/4 throttle chops but couldnt fin a spot long enough to safely kill it to a rolling stop .
The plugs were never wet looking though so im thinking ill be on the safe side and richen up the fuel scew half a turn and richen up the pilot maybe 2 clips . Our snow is just about gone so itll be awhile before i can try it again . next time im gonna take some pics of the plugs and post them . Id rather be on the safe side . besides the girlfreind bought me a whole box of plugs for xmas so I can afford to foul a few .
OH by the way the (BING BING ) noise was the TORS , I didnt even have it plugged in before , noticed that and wanted to slap myself in the head !
 
At least you have been able to get out on it. I still haven't had a chance to get mine out. No Snow :( Sounds like your going in the right direction. I have hopes of getting on mine for a short time today but the snow is getting lighter as I type.
 
After reading this whole thread, I'll add my 2cents to it.

It sounds like your "testing" your jetting with brand new plugs in it, correct? I would try to check it with some old plugs, they show color a lot sooner than new plugs. New plugs can take a while to color up to give you a proper reading. Mrviper is giving you excellent advice (sled guru), you want to be careful about running it too lean!, and checking on a stand won't work. After you ran it 85mph back home and saw white plugs, definitely better pay attention to jetting. Don't go off of what Bender jetting charts say, and that you heard their spec is "pig rich", because every sled is a little different. You also gutted your air box which will lean it out, on top of head gasket mod. My bet is Bender's jetting chart is simply for their pipes, NOT air box gutted, etc., on top of that. It is very hard to get yourself to spend the time checking and re-checking plugs when you have new triples on and want to RIP!, but you need to accept that your going to have to spend the better part of a day or more checking plugs, pulling carbs and re-jetting, and then repeat process. Your lucky that you were burping in and out when you saw the white plugs, probably the only thing that saved you from burning down. Your not going to instantly foul plugs when running rich either, so don't worry about going through a box of plugs. I would order the next three bigger sizes of main jets and start from there, they're cheap compared to burning down, and richen up the needles also. VERY CONCERNED YOU ARE GOING TO BURN DOWN IF YOU DON'T!
 
Thanks for the input MOD-IT , Actually Bender calls for the airbox mod in their install instructions for the pipes . That the only reason I did it .
And yes I was starting with new plugs , lesson learned there .
I spent some time today tearing into the carbs again . I set the fuel screw out to 2 turns , they were out 1.75 . Im trying to figure out how to raise them needles right now and for the life of me . i dont see any clips to take off . there are a bunch of linkages behind that cover . Any help ?
 
let me put my 2 cents in about benders jetting.i burned 2 pistons down after i did the pipes,head gasket,air box mod.listen to everyone,if your plugs are white it is lean and will,let me repeat will burn down.i have two pistons to show you if you don't think it will.don't go by benders jetting specs,it's different for every sled.oh yea,where in upstate ny are you located? :nos:
 
I have to say Im 110 % posotive the fouled plugs after start up were
totally my fault . !
I didnt let it warm up enough to take off with , and the reason they were white is because they were brand new , like 3 minutes run time on them .
I appreciate all the concern about burn down but , im not that close to the hairy edge trust me . My plugs are between a cardboard brown to a dark brown . Im very close to where i want to be but I want to try and fatten it up a bit just to be on the safe side .I would just assume foul plugs every ride then burn a whole in a piston . I just need to know how to raise the needles . Thanks .
Oh im from Port henry , on Lake Champlain .
 
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to raise the needles youll need a ball nosed 2.5mm allen wrench, you have to remove the cap top caps and then hold the throttle linkage open with a strap around the handlebar, then down inside youll see the 2 screws, remove them and the slide will drop down, you carefully tip the linkage off the shaft and then you can get at the clip. its alot easier to have the airbox off so you can stick your finget under the slide and get the needle up where you can get it out, take your time and dont lose the 2 plastic shims for the clip.
 
I got out on mine for a while today. I am still running with the airbox whole. I think I am running pretty good with the 55/170s. I keep wanting to say it is piggy rich, but across the middle the plugs look really good. Top end I don't really know. I still don't have a place to just hold it open. I have a slight bog when I mash the throttle open. My fuel screws are at 1 7/8s still.

I have some issues with my clutching yet. I Think I will probably end up changing the gearing. I have the ER gears so it is geared high, and the 136 probably makes it a little worse?

Have you changed that bent pilot? I bought my last jets from the dealer. They were really cheap. I bought a few different ones. Now I just need to pop the carbs out and swap them. I really need to get better about my note taking. I write it down and then loose what I wrote it down on. I need to get a folder together for tuning.

How bad is your fuel consumption? I haven't really checked mine, but with the limited riding I have done I have used 8 gallons. Not sure on how many miles, but it hasn't been many. My only concern is being able to catch enough gas stations on them long hauls. :) At Least with the tunnel extension I have a spot for a gas can.
 
Also wanted to ask if you have seen your DCS come on yet? What kind of temps have you had? Cold enough to really test? In the 30s here today...
 
just keep your eyes on the plugs and piston wash, let the engine guide you as to what it wants.
 
I agree with what your saying MrViper, wasn't telling him to jet to the DCS. I was just curious about it. I have heard a lot of people with the piped vipers and DCS that constantly fight the DCS.

Now if I could just figure out what it is my engine is telling me. got this whole language barrier thing going on.
 
Thanks MRVIPER , I got into them needles last night .
I havent changed the pilot yet , it seems to be ok . I havent had any issues with it sticking so far . I turned the fuel screw out to 2 full turns and set the needles to the bottom notch .
All of our snow is ice now so I cant get out to test it again . but at idle and revved to 7000 on a stand the plugs are very wet (BIG DIFFERENCE ). I know a stand test doesnt show real world but I just wanted to see how much difference the needles made , before it was brown at this rpm on the stand .
I saw the DCS come on once when first started for a millisecond but thats all . I rode it for about an hour on christmas eve day and the DCS never came on , thats why I figured I wasnt to close to the the hairy edge of being lean . I really appreciate all the help from you guys here ,its been a pretty nerve racking process so far but I think Im getting it dialed in to a safe spot . I may have to bump up a size or two on the main jet but im real close .
Next time I take it out im gonna take a few pics of the plugs and see what you guys think .
 
You said you moved the needles to the bottom notch? I hope you don't mean you moved them to the VERY bottom notch.
 
Don't ignore your low and midrange. It took me almost a month to fine tune my pipes. I can,t count the number of times I had my carbs open
 
Yes , the bottom notch .It was in the middle to start with now its WAAYYY too rich !
Im going back up one notch . and back in a bit with the fuel screw , Its a constant bog and burble all the way up to 3/4 throttle then it wakes up . also plugs are dripping wet and the sled smells like raw fuel . I rode it about an hour like that and jeez did i stink like a gas station after . I even threw a set of BR8ES plugs in it to see if it would get better , nope . I wasnt too worried about a melt down running that rich . my buddy just picked up an 07 REV 600 . sad to say I was way impressed with his sled compared to mine . But im not giving up . Im building a ripper if it kills me !
 
I havn't touched the needles on mine, just turned the fuel screws out 2 turns and it responds very well. It burbles a bit but no loading up or fouled plugs. Put the needles back to stock, set the feul screws to 2 - 2 1/4, be sure the floats are set to spec, adjust the idle to 17-1800 warm and it should rip. It's going to be a blast when its all set right. Glad to see your not giving up. You'll get it.
 
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w8tn4snow, sounds like you got a little carried away with your adjustments. :) I am on my way out to do my clutches and make some changes on my carbs. I think we have the right ideas, just need to get it done.
 
I backed off the wrap on my secondary to benders spec. So I wanted to test that. I got out on the trails and they were much better than I expected. I got to do a couple WOT runs and take a look at what I have. When I pulled the plugs they were wet and shiny. So I am off to change my jets now. I am going to skip past the 167.5s and go to the 165s. I think that is safe with how wet my plugs were. Tops of my pistons were completely clean. I tossed a set of old plugs from my VMax in it for one of the runs. It washed them clean and left them wet too. Any input?

edit to add; 25* and humid unknown. My meter is taking a break on me.
 
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With your plugs being as wet as im thinking by what your saying . Im just picturing your machine loading up and not revving very well ., mine was a dogg when it was set pig rich . I think your on the right path leaning it out some . Keep an eye on them plugs !
Im shooting for carboard to dark brown plugs myself . Now that i know what too lean and too rich is , Im going for somewhere in the middle and hope i hit the sweet spot . good luck !
 
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