800 cc Pilot screw setting?

northernsledder.jk

northernsledder.jk

New member
Hello, I have a few questions:

I have my 800cc carbs on the bench now for cleaning. I'm replacing all four needle & seats/o-rings and float bowl o-ring seals. I also pulled the pilot air screws to replace the little o-rings in there. Glad I checked them, because they're disintegrating like the other o-rings are.

My question is: how many turns out (from lightly seated) are you guys setting your pilot screws at? All 4 of mine were different and the service manual doesn't list a starting point; manual says, "Pilot screws are set at the factory and should not be changed. If they are removed, record settings and return screws back to same position upon assembly!" My carbs all ranged from 1/4 to 1-3/4 turns out?? lol :help:

Past carb experience says 1-1/2 turn out is a good starting point, but maybe that's not the case here? I've owned this sled for two years and this is my first time having the carbs apart as it was starting to run rough last winter.

Thanks to the site and the people that take the time to post service work! I would have never known where to start on this sled!:smilies-9
 

2 turns out.The more out,the more fuel.In more,less fuel.These are fuel screws.I do believe that some mistake these for pilot air adjustment.
 
My carbs were in pretty bad shape; all main jets, pilot jets, o-rings, needle & seats and aluminum pilot jet tubes had to be replaced. It took several hours scraping all the nooks and crannies in the float chambers with a knife before they even got soaked in carb cleaner. All is reassembled and going back on the motor this week. I have a new Bender silencer to go on as well!

Thanks for the replies! Much appreciated!

carb1.jpgcarb2.jpgcarb3.jpgcarb4.jpgcarb5.jpgcarb6.jpgcarb7.jpg
 
Is the pic of the carb rack in completed cleaned state? It looks like the tiny air jets/plugs are missing.
 
I raised my needles with the bender silencer on. Heard from a wise old vmax 4 chap that they created a bad lean spot in the midrange.
 
Hmm. I specifically asked them about jetting and they said stock was fine (143.8 mains). They did not, however; say anything about raising the needles. How much did you raise your needles? Did you first make a run before making changes?
 
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It's been awhile since I tore into those carbs but I believe it was only one position. I actually only found out after I had a sled with the stinger already on it. I removed the stinger for some repair and put a stock can on so I could use the sled in the meantime. Sled was acting real bad after being crisp and responsive. After asking some questions and hearing about the lean spot created by the stinger and that the needles should be raised I checked. Sure enough they were raised. Any sled I use a bender stinger on I'm sure to raise the needles. This is on the 750 motor however which may be the difference. Not sure. I am almost certain it was Yammiegod who brought this to my attention. I use a bender stinger on my 800 that I race but it never sees midrange, maybe for a split second so I left needles in stock position.
 
It's a bit of a pain to raise needles but not too bad after 1 or 2. I prefer to remove carbs from sled and then take the top off the carbs and go at it from there. You'll need a good Allen key set in metric and make sure of a good fit. I wish I could explain it better but you'll see what you need to do once you open the top of the carb. Do one at a time so if you have to open another one up to see how it goes back in you'll have that option. There are 4 Allen head screws that hold the assembly you'll see to the slide. This is also a good time to set the slide height to match on all 4. Lower the clip to raise the needle is the most important part. My god that's not a great explanation. It's been awhile.
 
If You try it with the carbs On the sled. I guarantee you will lose the tiny plastic washers under the clip! Remove the carbs.Easiest way is to jam the throttle open. Get a Allen head wrench that is long and has the ball end. Pay close attention to the tiny plastic washers. They stick to the needle or the slide.
 
Ok, I spoke with the gentleman at Bender that sold me silencers. He said as long as my jetting is stock, there is no need to re-jet. I'll still check my plugs though to be sure.

Good posts!
 
Yes there is.Take the covers off the top of carbs.With carbs in closed position,remove the 2 phillips screws that attach the aluminum thingmabob to slide(they may be allen screws i forget).Do this on all 4 carbs.Then open carbs to wide open and zip tie them that way.Next is to remove the aluminum thingmabob off each carb,they are held on by the spring and should come off with a little force(dont mix these up from carb to carb).Now keeping carbs in upright position,push the slides up enough as to expose enough needle so that you can push them up and out of the slide.Keep in mind that there is a tiny plastic washer on the needle under the "e"clip,dont lose it.it may stay stuck to the slide.Also,those air jet and plug that look like they are missing in your other photo,dont get them mixed up or you will have trouble.The solid plug goes in the bottom/center and the air jet is on the left.Hopefully this isn't too confusing as I tried to explain the best I could.
 
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