03 Viper High Idle and Backfiring

I wrote the same thing and changed "just in front of the main jet" to "just behind the main jet... engine side".

Sounds to me that you've done a thorough job cleaning the pilot curcuit.
 

So my Viper was doing this too. to some degree, still does. Last year, it wouldn't idle unless the choke was on a bit. Brought it to a friend of mine and he went through it. Clogged pilot circuit. But when I got it back, it would idle high, rev up to clutch engagement, and them slowly work its way down. Drove me crazy! This year, he did more to it, and seems to have got it to a point where I can live with it at least. He has the screws set to 2 turns (pretty sure that's what he said), and my idle truned down to aroudn 1500-1600. Seems better. Still seems to come down slowly, but the rev up to 4000 seems gone. But I'm thinking there still is more too it, so I'll be watching this thread myself. I really need to get comfortable with cleaning my own carbs and pulling them. I'm pretty mechanical, but that just intimidates me due to syncing, all the cabling, etc. :)
 
i know what you mean about the intimidation part. There's not much to it though really. I just started doing it myself 4 or 5 years ago. take the airbox off which is nothing but screws a bolt and the clamps holding it to the carbs. move the cables off to the side and pull the box out. After that, unscrew the clamps on the other side of the carbs then follow "carb cleaning 101 with pics" by mrviper700 in the tech section. pretty simple when you do that.

For the ones helping with this issue of mine... with pilot circuit and carbs completely clean, could this be a combination of sticky power valves and ypvs adjustment? i cleaned the valves already although I know they are not spotless but with the carbs being clean I'm lookin for possible direction "if" the problem still exists.
 
With rack mounted carbs there is no need to resynch carbs. If everything is already adjusted, just take care to leave the jam nuts on the cables 1/2 turn or so from where they were and simply turn them the same amount back upon reassembly. It really is very easy.

Power valves will not affect idle or low range. If they are stuck open they will affect snappiness but it will still run fine. Normally PV's stick closed though and this affects top end.

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Its not hard. Lock nut to loosen the choke and throttle cables, then back the cables out which u can do by hand. I wouldn't use tools to back them out after the lock nuts are loose or u may cross thread them. Once they are backed out all the way lift them up and out of their respective slots then take the cable and lead ends out of the choke and throttle. That's pretty much it for that. You'll have to remove the fuel and coolant lines. Use pliers to slide the tension clamps down the lines then take them off. I prefer to push them carefully with some lome long nose pliers to start them sliding back then remove them the rest of the way by hand. Plug them with some golf tees but keep in mind.....do not use painted ones. Lol. Found that out the had way. Slide the tension clamps up to keep the tees in and to allow nothing past them.
 
IMG_20140128_183441642.jpg. My dad mentioned that if the screws were.put in too far they could be damaged and would have a ring around them. Does anyone see anything wrong with these ones?
 
I think I see a slight hourglass shape on them. Does anyone see that? I'm suspecting that's not normal but I've never looked at another set before to compare. Would that cause the slow come back once you let off the throttle?
 
Thanks for the tips. I need to tackle this. I'll try this summer when I don't need the sled to be operational. :)

I see the hourglass shape you're talking about. No idea if that's normal, but I'd find it interesting if it wasn't. What could cause it to do that if not normal...curious to see what the others say.
 
sweet. thank you. I've never seen any fuel screws other than the ones in the pic I showed. I have yet to have time to get these carbs back on the sled....hopefully tonight I will.....but it's killing my mind thinking about the scenario when I get it all back together and it does the same dang thing it has been. I will for sure know its not the carbs though. Unless, there is somehow something in my tank but that's highly unlikely. With other people having the same problem with the rpms not wanting to come back down after letting off the throttle and not having a true "this is the problem," it's not providing me with the warm fuzzies I would like to have about this issue. Although....that is why I'm on here with ya'll having my back so I will try to kcco and adapt and overcome. :-) Thanks again to you all.
 
Sometimes just talking sweet to them helps.

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put the screws at 2 -1/8 turns out from lightly seated this time, thats 2 full 360 degree circles and then a 1/8th turn, that will richen it up and solve your issue. Also the other tip is to make sure you dont bump the rubber boot on the tors switch and get it beteeen the tors switch and the carb cam,as it will cause a high idle. its the round rubber boot on the end of the switch,switch contact goes down thru the center of it.
 
Say that does fix the prob...that would concern me because it would raise the question, what changed so that it had to go from 1-7/8 to 2-1/8 turns. Everything has been set to stock specs previously
 
Everyting I've read though, including what my fried did, is in additional the additional fractional turn, was to turn down the idle to around 1500-1600 as mentioned earlier too. That seemed to be a key part of it.

I'd like that question answered too though...
 
Grimmy said:
Say that does fix the prob...that would concern me because it would raise the question, what changed so that it had to go from 1-7/8 to 2-1/8 turns. Everything has been set to stock specs previously
Click to expand...

I would say from 56 post now on this that your way over thinking it, and just give the sled what it wants which is slightly richer mixture and a lower idle speed like the rest of the vipers out there. many vipers when new needed richer fuel screw settings.

from 1/7/8 to 2-1/8 is hardly anything........your measuring hairs and thin ones at that.
 
Well it's official. Its not the carbs and I'm sick of not being able to ride. So much to my weekend trip. I know dang well these carbs are clean. I can get it started, idles at 3800 and won't come down. When I back the idle screw out it then starts to come down but will die if I dont put the idle screw back in a lil bit. I actually got it to idle at about 1900 once and the second I touched the throttle It spiked to 4000 again and then stayed there. I backed off the idle screw again and it came down, scewed it back in a bit to stop it from dying and when I bumped the throte again it stumbled and then backfired and started revving up again so I just shut it down. I can get a tps for it for 30 bucks.......not sure if I'll be able to just match up the mounting of it to the original one but its either that or put it in a shop and have them charge me a ton of money....to probably tell me its the tps and then charge me 120 for a new one. This whole thing has been circles.
 
tell you what give me your phone number, i can solve more in 5 mins on the phone then 57 more post. pm me your phone number
 
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