tkiss1 Posted January 3, 2014 Report Share Posted January 3, 2014 So I bought a quad a few days ago. It has Athena head, v force reeds, boost bottle, fmf exhaust with K&N filter on open air box. I don't know much about quads or two strokes to be honest, I took the carbs off to soak them in carb cleaner and noticed the shee had stock jets still. Put everything back together and had the mixture screw at 1 1/4 when it was about 30 degrees out and was running decent low end. Last night it got ridden for a few hours and the temps were about 15 degrees outside and towards the end of the night when you gave it a little gas it would just rev out and wouldn't fall back down unless you gave it more gas and let go quick , everytime I shifted it it would rev out so it was kind of hard to ride. As far as I knew when the motor revs out and doesn't fall back its running lean, I adjusted the mixture screw to about 1/8th turn out and still does it. I am kind of stumped at this point on why its revving out so much when I cant richen it any more and it was running fine in a little warmer temp. The throttle cable is fairly new and I also moved it around to see if that's what was caught up but it didn't make a difference. I also purchased a stage two jet kit from dynajet for the future, Quote Link to comment Share on other sites More sharing options...
tdod101 Posted January 4, 2014 Report Share Posted January 4, 2014 Just out of curiosity, after you dipped your carbs in carb cleaner did you drop them in a pot of boiling water and than blow all the holes with compress air ? Quote Link to comment Share on other sites More sharing options...
tkiss1 Posted January 4, 2014 Author Report Share Posted January 4, 2014 I didn't do boiling water but I did as hot as I could from the sink and shook them around in the water then blew all ports and the whole carb with air compressor. That's normally how I always done carb services and I had no issues in the past. Quote Link to comment Share on other sites More sharing options...
tdod101 Posted January 4, 2014 Report Share Posted January 4, 2014 I didn't do boiling water but I did as hot as I could from the sink and shook them around in the water then blew all ports and the whole carb with air compressor. That's normally how I always done carb services and I had no issues in the past. Okay that's good, I do it too, from what I gather you might have an air leak ? Have you done a leak down test yet ? Quote Link to comment Share on other sites More sharing options...
tkiss1 Posted January 4, 2014 Author Report Share Posted January 4, 2014 I have not. Is there a link for that procedure? Quote Link to comment Share on other sites More sharing options...
tkiss1 Posted January 4, 2014 Author Report Share Posted January 4, 2014 Okay I searched and found the procedure , I will make a test kit and check it out Quote Link to comment Share on other sites More sharing options...
tdod101 Posted January 4, 2014 Report Share Posted January 4, 2014 Good stuff! 1 Quote Link to comment Share on other sites More sharing options...
tkiss1 Posted January 5, 2014 Author Report Share Posted January 5, 2014 I didn't do a leak down test just yet but, I did do the jet kit since it came in. I noticed the needles that were in there were off by like 3 spaces so one clip was at #2 grove and the other one would be at like # 5 grove. Obv that was not good but still shouldn't affect the low end , that's all taken care of now though. I ran the quad again and still same thing low end. It idles fine and when I slap the throttle it will come back down to idle fine. If I ease the throttle a little and let go that's when the motor stays revved and wont fall back down till I slap the throttle again. Its odd because it doesn't happen every time but even when I rode it everytime I held the clutch in it would rev up between shifts until I gave it a lot more gas to clear it all out. the mixture screw at this point is all the way in and runs the "best" that way rite now but obv that isn't good yet, Im just wondering with those symptoms if it would still be an air leak since it does idle fine until I give it slight throttle. Im just a little confused obv not sure if I Just need one pilot jet size up or what! Quote Link to comment Share on other sites More sharing options...
sprinklerman Posted January 5, 2014 Report Share Posted January 5, 2014 <p>No point in trying to jet it until you do a leak down test 1st. ..like everyone is telling you.</p> Quote Link to comment Share on other sites More sharing options...
tkiss1 Posted January 5, 2014 Author Report Share Posted January 5, 2014 I only jetted it because it has to get done either way since the stock jets aren't going to be sufficient. But in your opinion with the symptoms im mentioning now does that sound like an air leak? Quote Link to comment Share on other sites More sharing options...
dave5.0 Posted January 5, 2014 Report Share Posted January 5, 2014 With the mods you have and the jetting being "stock" and it was 15 deg when you rode it I can't believe you haven't turned it into a molten pile yet. Do you have 13 threads going already that I've missed besides the camber one? Have you told us what jets you put in it? Kinda hard from what I've seen so far to help you when all you did was "jet it". That doesn't tell anybody much. We need numbers. Quote Link to comment Share on other sites More sharing options...
tkiss1 Posted January 5, 2014 Author Report Share Posted January 5, 2014 (edited) There is a reason im on this forum and its because im not to familiar with quads in general. No I only have these two threads. I searched but couldn't get a clear answer to my symptoms that is why im here asking for help. I mentioned in my original post that I was getting a stage two kit from dynojet which I thought was pretty standard. The pilot jets are stock which is 25. The main jets now are 280 which is the recommendation from dynojet. Im pretty much at sea level. The temp outside now is 37 degrees. Mixture screw is in all the way. instead of the 1 1/2 turns out and that's when it gets closes to running "good" The quad Idles fine and will sit idling for as long as I want. Its just when I give it slight bit of gas it wont fall back down to idle until I rev it up quick and let go. From my understanding an air leak would cause erratic idle. A lean condition would cause it to rev up also that's the only reason im confused. I am going to do the leak down check I just figured with these symptoms it could be something else maybe. To add it looks like the exhaust gaskets are leaking a little because there is oil on the front by the exhaust ports so im not sure how much that would affect this particular issue. Edited January 5, 2014 by tkiss1 Quote Link to comment Share on other sites More sharing options...
dave5.0 Posted January 5, 2014 Report Share Posted January 5, 2014 I just jetted one here while back with pipes and reeds. Ended up with a 30 pilot. If you have the screw all the way in it wants more fuel. That 25 is a stock jet. Probably gonna end up 1-2 sizes bigger atleast. I usually adjust a pilot by idle speed. If you have the right pilots in there you should be able to set an idle, then adjust the screws evenly 1/4 turn or so at a time until you get the highest idle. If you go in more than I think 1-1/2 a turn pilot is prob too small. If you go more than 2 1/2-3 out its prob too big. Once you get that ironed out move to the needle. Go all the way to the bottom with the clip on the needle. If its the right needle and the pilot is right it should idle fine and then stumble when you rev it. So come up the needle one clip position at a time until it clears out. Once that's clean put some big ass mains in it. Maybe 330-40. Hopefully it'll stumble on the top end. If so its big enough. Then come down one size at a time until it clears out on top. Once there run it through the gears to 5-6th. While wide open kill it and pull the clutch at the same time. Then Look at your plugs. Ideal is gonna be chocolate brown. This way isn't the most horsepower per say but it should run good and be safe. The motor will last this way. You can make more power possibly being on the edge of lean but I'm gonna assume you're just riding it like most of us are. The way I lined you out is a way to keep it going for a while and you won't have to worry if its gonna grenade because its too lean. I've never done any plug chops like a bunch of guys are gonna tell you to do. I haven't melted one down in a long time. Plug chops seem like a waste of a new plug to me. Especially of you aren't chasing any records. Quote Link to comment Share on other sites More sharing options...
tkiss1 Posted January 5, 2014 Author Report Share Posted January 5, 2014 all that makes a lot of sense. I tried getting parts together for a leak down test but couldn't find anything for the intake side to plug it up. I will search tomorrow some more. I will order a bigger pilot jet and try that out. That's what seems like the issue is here but I didn't want to risk it because I know air leaks will cause a lean like condition also. Thank you for all the information. Quote Link to comment Share on other sites More sharing options...
dave5.0 Posted January 6, 2014 Report Share Posted January 6, 2014 Take an intake or measure one and buy some cheap PVC fittings. Thats what I made mine out of. Couple threaded bushings to screw a gauge in one side and fitting to put air in the other side. Then if ya don't have the bumper caps buy some rubber Fernco pipe caps wherever you get the PVC fittings for the exhaust. They'll come with hose clamps already. It doesn't have to be a perfect deal just seal up good. Piece of cake to make up. Quote Link to comment Share on other sites More sharing options...
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