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+--- Thread: Nitro tune (/thread-4228.html)
Nitro tune - Whitey04 - 08-09-2006
I had just purchased a kyosho mp7.5 and I set the needles to factory settingsor atleast what the manual said was factory settings. The thing is running rich as hell. I mean like I can pour fuel out of the exhaust. Is this normal and is it normal to have to adjust alot to get the motor in tune. Also I can't seem to keep the motor running, at idle or if I burp the throttle it will kill it, also I can seem to get the motor started unless I feed the carb a little fuel first. Are all these things normal until the motor is in tune?
On another note, are there tell tale signs that somethings not right? Like to much smoke is some normal? Should I use that after run oil? On the needles does clockwise = leaner and counter = richer? It seems that way. Sorry about all the newb questions but it my first nitro car and I am just kinda learning as I go. Thanks in advance.
Nitro tune - Ponch - 08-09-2006
Whitey04 Wrote:I had just purchased a kyosho mp7.5 and I set the needles to factory settingsor atleast what the manual said was factory settings. The thing is running rich as hell. I mean like I can pour fuel out of the exhaust. Is this normal and is it normal to have to adjust alot to get the motor in tune. Also I can't seem to keep the motor running, at idle or if I burp the throttle it will kill it, also I can seem to get the motor started unless I feed the carb a little fuel first. Are all these things normal until the motor is in tune?
On another note, are there tell tale signs that somethings not right? Like to much smoke is some normal? Should I use that after run oil? On the needles does clockwise = leaner and counter = richer? It seems that way. Sorry about all the newb questions but it my first nitro car and I am just kinda learning as I go. Thanks in advance.
Alright, is it new or used? The motor that is. If it's already broken in you can start by leaning out the high speed in 1-2 hour increments until you don't notice any more top end gain. Then back it off about 1/8-1/4 turn.
Then adjust your LSN so after a high speed run, you bring it in and pinch the fuel line about 1 inch away from the carb. It should idle high for about 3 seconds and die out. If it idles longer it's too rich, if it idles shorter, it's too lean on the low speed.
Then adjust the idle, you should be able to go from a high speed run, stop, and the car shouldn't move, like creep forward on it's own. Then it shouldn't die out on the other hand lol.
I never use ARO except if I'm going on vacation or something. If I'll be running within about the next 3 days, I leave it without ARO. You are correct about the leaner=clockwise, richer=counterclockwise.
Hope this helps some.
Nitro tune - Whitey04 - 08-09-2006
helps alot, thanks. now is it bad to bench set? You know WOT on the bench, just to close set it then track set it closer. By the way the motor is brand new as is the buggy. And I'm not diggin this pull start thing, My finger and chaffed. This thrusday I'll be purchasing a starter box, friday I hope to make it to leisure hours to break this thing. Sunday I'll take it to busse woods meet to definitely break it if leisure doesn't do it. J/K I don't want to kill this thing yet. I've got about 1.5 tanks through it tonight and spent more time pullin that pull start then running it. My arms are killin me. I'm probably going to purchase a new radio also, It seems as though the rtr radio is rather noisy. Servos seem to alway be glitchy, makes me nervous with no fail safe.
Nitro tune - Ponch - 08-09-2006
I assume you know how to break in properly?
I usally idle a tank, then run 5-6 tanks in slow figure 8's, increasing speeds to full by the 7th tank, but only for 3 or so seconds.
Nitro tune - Czech-it-Out Graphics - 08-09-2006
break it in by just running it rich with a sock or sumthing on the head to get the temps up around 220 or so. i usually run 5-6 tanks through and then just race tune it. you want to set the HSN first like R2k said, but set the idle to that gap that is shown in the manual, u can eye ball it to where it looks close to what the manual shows, from here on out u shouldnt touch the idle screw. The idle is set with the LSN. If the idle is way to low lean the LSN too high Richen the LSN tune for good smoke throughout the entire power band tempos of 260-280 are ok with good smoke and a good crisp sound
Nitro tune - Tex - 08-09-2006
you should read this
http://www.chitownrc.com/showthread.php?t=3439
Nitro tune - cemeb4dk - 08-09-2006
http://www.rchobbies.org/cars_eng-tuning.htm
Nitro tune - Whitey04 - 08-10-2006
Yeah I've printed out that article. And yes I'm still breakin in the engine. I've got 3.5 tanks through it, I got the carb set so it will start but its still very pig rich. Loads up about every 10 seconds or sooner. Can't idle for long without burping the throttle to clear out some fuel. I'm getting the hang of it. Its not really that difficult, just a few more tanks and i can finally tune this thing. Like I said though I'll be at leisure hours friday night and sunday at busse so if anyones out stop and school me!!
lap:
Nitro tune - Ponch - 08-10-2006
Sounds like you got it about right where it should be for break-in.