i have a NTC3 and the darn thing seems to bog real big before it takes off. it sounds like I'm choking the damn thing (lol). It also wont go INITIALLY from rest with the throttle engaged and rev'd up slightly, it does the bog thing and then decides to move. ALSO, after i get it to "warm up" it doesn't seem like its switching to 2nd gear. After i get it to run for a while, its fine (except for switching gears) until i get it to a rest....then it starts all over again. does anyone have ANY answers for me. Could it be the not switching gears is the cause of everything, or could it be stuck in 1st or 2nd gear. please someone help. this is my first experience with r/c and i would like to see how my car is SUPPOSED to run. Thanx to all who reply.:bow:
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nitro dave
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It sounds like to me that perhaps your LSN(low speed needle) is too rich. I would check both of your needles. I don't have an NTC3 yet, but I think I heard that it shifts really quietly, so maybe it is hitting 2nd and you don't hear it. I could be wrong. I do know that you can adjust the shift point. You might want to lower it. Also, how is your idle? Does it seem to idle ok. I know that affect my maxx's ability to shift.
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thanx guys for responding so quickly. you're great. ill give that a try. in response to dave, it idles ok for a little while then it gets to sound like its gonna die on me so i give it a little gas. I'm pretty sure if it would sit there for 30 secs without me doing that, then it would kill. again thanx guys!!!!
Oh boy. This is going to sound odd comming from the forum "Novice", but my buggy has done this exact same thing before.
Think about the carb. The LSN sits inside the spray bar and that spray is what gives you the air / fuel mix while it's sitting idle. What happens when you pull the throttle? You get more air right? Yes, but you also back the LSN out, away from the spray bar. Whats that do? That dumps as much fuel into the carb as the HSN will allow.
If your HSN is too rich, the excess fuel will cause the car to bog down and maybe die when you start to give it gas. Furthermore, because it's so rich, the top end wont reach peak performance and the RPMs wont be enought to shift you into 2nd gear.
The reason why you have to "warm it up" is because as the engine gets hotter it leans out the air/fuel mixture. This is why we're told to warm the engine up before we start tuning. In your case, the leaning out caused by the engine tempature is enough to compensate for the rich HSN needle setting and let the car move.
My diagnosis: your HSN is too rich.
Warm up your car and then slowly lean the HSN 1/12 of a turn. It should eventually shift into 2nd and the weird problem with it bogging down and not moving when it's cold will go away.
Good Luck,
Rob
Think about the carb. The LSN sits inside the spray bar and that spray is what gives you the air / fuel mix while it's sitting idle. What happens when you pull the throttle? You get more air right? Yes, but you also back the LSN out, away from the spray bar. Whats that do? That dumps as much fuel into the carb as the HSN will allow.
If your HSN is too rich, the excess fuel will cause the car to bog down and maybe die when you start to give it gas. Furthermore, because it's so rich, the top end wont reach peak performance and the RPMs wont be enought to shift you into 2nd gear.
The reason why you have to "warm it up" is because as the engine gets hotter it leans out the air/fuel mixture. This is why we're told to warm the engine up before we start tuning. In your case, the leaning out caused by the engine tempature is enough to compensate for the rich HSN needle setting and let the car move.
My diagnosis: your HSN is too rich.
Warm up your car and then slowly lean the HSN 1/12 of a turn. It should eventually shift into 2nd and the weird problem with it bogging down and not moving when it's cold will go away.
Good Luck,
Rob
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Nitroaddict
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This is the exact answer. I have an NTC3 and had the same problem. your LSN is too rich, causing it to flood the engine with fuel while sitting at idle. By not reaching a high enough RPM, it will make the vehicle shift sporadically. Do you know how to adjust the shift points? If not, I will help you with that too. Feel free to PM me if u want more information, as I have had my NTC3 for a while now, and learned all of the little nuances it has.
HumboldtBlazer
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Also in my experience if the idle is too low then the egine will not reach a high enough rpm to shift.
nitro dave
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That has been my experience too, which is why I asked about the idle.
nitro dave
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they say a picture is worth a thousand words, so lets see if this works
ND
ND
kwong2001
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you'll also find that you'll have a lot more torque when you get the LSN set correctly. When I set the idle, i just more listen to the engine and if it sounds like it's gonna die, give it a bit more idle
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hey guys, i tried the several tips you all suggested. it helped alot. it doesn't bog as much, but still just a little. i did notice that after running it and then bringing it to a stop the idle is just a little higher then after its sits for a few seconds--the idle seems to drop some after sitting a while. however, it doesn't ever cut off, and it doesn't sound like its gonna die. it just seems to drop some. and now its only when the idle drops some that it seems to bog a little when i give it throttle.
in all my tweekin' this am, i would like to know how do you determine when to stop leaning your needles. I've been told that having your car too lean will destroy your engine. this uncertainty is probably why i didnt try to further lean out my needles, to see if i could totally fix my prob. i thought i would consult with the EXPERTS first.
in all my tweekin' this am, i would like to know how do you determine when to stop leaning your needles. I've been told that having your car too lean will destroy your engine. this uncertainty is probably why i didnt try to further lean out my needles, to see if i could totally fix my prob. i thought i would consult with the EXPERTS first.
HumboldtBlazer
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sounds like you got it tuned pretty well now. In my understanding the slight idle drop after a molment of sitting is normal. The engine while idling is "loading up" with fuel so when you take off the is a lot of unburnt fuel in the cylinder hence the bogging until it opens up and burns the fuel. There should be very minimal bogging. This is the case on all my engines so I think it is normal but if someone knows different please let us know.
