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Old 03-03-2010, 06:37 AM   #16
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Thank you very much fellas, all your advice was great, I went to see my local shop yesterday and the guy was more than happy to assist, turned out my low speed was wayyyy too lean (that's what you get when you follow badly translated manuals where the piture doesn't match what's written and you actually had to follow the picture not the instructions :P)

now my car starts real good, went through a tank yesterday,

I was told by the shop to only adjust the high speed every 2-3 tanks, and once the breaking in is done (after 6-8 tanks) then adjust the low speed to the desired setting.

tonight I'm heading out with my cousin for some driving in a parking lot, should be fun.

P.S.: While I went to the hobby shop, my cousin on the other hand read what was here and got his going before I was out of work.

Once again, thank you very much

Oh, and my controller was pulling too much on throttle servo when fully pressed so he trimmed that properly also, all in all it was a good learning experience so far (still ways to go)

and 3 quick Q's for you guys

A) what should i clean my air filter with, cause I got me some spray but the filter is dirty a bit from yesterday's run, and since there was no liquid on it, I wanna clean and spray.

B) Does any1 know of any Mitsubishi Evo X 1/8 scale body I can get from somewhere? I know Tamiya has the 1/10 but I'm looking for the 1/8 (if any)

C) are there silencers that can be install for the exhaust to make them less noisy (Last night i woke up the neighboors while driving at night, they didn't apreciate it very much)?
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Old 03-03-2010, 07:15 AM   #17
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Originally Posted by Khar00f View Post
Thank you very much fellas, all your advice was great, I went to see my local shop yesterday and the guy was more than happy to assist, turned out my low speed was wayyyy too lean (that's what you get when you follow badly translated manuals where the piture doesn't match what's written and you actually had to follow the picture not the instructions :P)

now my car starts real good, went through a tank yesterday,

I was told by the shop to only adjust the high speed every 2-3 tanks, and once the breaking in is done (after 6-8 tanks) then adjust the low speed to the desired setting.

tonight I'm heading out with my cousin for some driving in a parking lot, should be fun.

P.S.: While I went to the hobby shop, my cousin on the other hand read what was here and got his going before I was out of work.

Once again, thank you very much

Oh, and my controller was pulling too much on throttle servo when fully pressed so he trimmed that properly also, all in all it was a good learning experience so far (still ways to go)

and 3 quick Q's for you guys

A) what should i clean my air filter with, cause I got me some spray but the filter is dirty a bit from yesterday's run, and since there was no liquid on it, I wanna clean and spray.

B) Does any1 know of any Mitsubishi Evo X 1/8 scale body I can get from somewhere? I know Tamiya has the 1/10 but I'm looking for the 1/8 (if any)

C) are there silencers that can be install for the exhaust to make them less noisy (Last night i woke up the neighboors while driving at night, they didn't apreciate it very much)?
I NEVER reuse filters, thats just me, I guess you can use nitro cleaner but you will need to get some filter oil
I have never seen any 1/8 evo bodies
And third - welcome to nitro. they are loud and you should drive them in from of your home at night.....Im pretty sure some one make a quieter exhausts but whats the point the noise is part of the experience.
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Old 03-04-2010, 07:04 AM   #18
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Hello again fellow racers,

New day, new problems (or not so new) me and my cousin went to the parking lot yesterday night for some racing (around 11pm about -2 to -5 degrees Celsius)

we had lot of difficulty starting the cars. I dunno if it's due to temperatures or what not (no pre-heating)

Also we experienced some "abnormal" behaviors from the cars. Here's how it goes.

First my car finally started by putting it on a block of wood wheels off the ground and giving it gas at the same time as I pull the string, after starting here's what happened.

while on the wood block the wheels turn a little, so i lifted the car and put it on the floor, car stays put, now if i just push on the gas a little bit, the engine would die, you see it trying to pull the car but just shuts off, I have to pump the gas and give it to about half way through for the car to actually "have enough power" to go. Now what happens afterward, after i do a few runs and drive it toward me and just let it stand, it wouldn't, without pushing any gas or anything, the car just drives off, and i mean drive off, like i can't keep up with it if i try and run behind it, so it's going quite fast. I have to constantly hold the break for the car not to move or turn the transmitter off so that the fail safe kicks in.


My cousin on the other hand, had a lot of difficulty starting his vehicle, he finally got it done after much tweaking of all 3 needles.

Another symptom he was experiencing is if he gave the car to much throttle it would die also.

And one more thing is that sometimes the string we pull on to start the engine gets EXTREMELY hard to pull like something holding it back, it doesn't happen often but it has happened and only time let's it loosen up, leaving it a few secs without pulling will make it pull-able again.

I know this may sound redundant, but I need some answers please,

Do cars need to be tweaked for start up every time we go outside depending on temperature? and if so, do we need to play with all 3 needles every time? or just a particular one or two (and which one(s))

Also about my car driving off by itself, what is the cause of that, and why doesn't it do it when i first power on my car, and why is it driving off so fast.


if someone can take the time to go over our situations and try and explain each step why it's happening just so we can have an idea on what to do next time, cause honestly yes the cars started, but it kills the experience trying to start cars for 45 mins before each run. At least knowing what i need to do before each run will make things much easier and funner, we don't mind the tuning of the needles and such (it's all part of the experience), but we never know what to tweak, like I said we end up tuning all 3 for the cars to end up starting, that's probably our inexperience, but if one of you fellas can help us out on that one, it's greatly appreciated.

Thank you,

Rodi
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Old 03-04-2010, 08:58 AM   #19
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Originally Posted by Khar00f View Post
Hello again fellow racers,

New day, new problems (or not so new) me and my cousin went to the parking lot yesterday night for some racing (around 11pm about -2 to -5 degrees Celsius)

we had lot of difficulty starting the cars. I dunno if it's due to temperatures or what not (no pre-heating)

Also we experienced some "abnormal" behaviors from the cars. Here's how it goes.

First my car finally started by putting it on a block of wood wheels off the ground and giving it gas at the same time as I pull the string, after starting here's what happened.

while on the wood block the wheels turn a little, so i lifted the car and put it on the floor, car stays put, now if i just push on the gas a little bit, the engine would die, you see it trying to pull the car but just shuts off, I have to pump the gas and give it to about half way through for the car to actually "have enough power" to go. Now what happens afterward, after i do a few runs and drive it toward me and just let it stand, it wouldn't, without pushing any gas or anything, the car just drives off, and i mean drive off, like i can't keep up with it if i try and run behind it, so it's going quite fast. I have to constantly hold the break for the car not to move or turn the transmitter off so that the fail safe kicks in.


My cousin on the other hand, had a lot of difficulty starting his vehicle, he finally got it done after much tweaking of all 3 needles.

Another symptom he was experiencing is if he gave the car to much throttle it would die also.

And one more thing is that sometimes the string we pull on to start the engine gets EXTREMELY hard to pull like something holding it back, it doesn't happen often but it has happened and only time let's it loosen up, leaving it a few secs without pulling will make it pull-able again.

I know this may sound redundant, but I need some answers please,

Do cars need to be tweaked for start up every time we go outside depending on temperature? and if so, do we need to play with all 3 needles every time? or just a particular one or two (and which one(s))

Also about my car driving off by itself, what is the cause of that, and why doesn't it do it when i first power on my car, and why is it driving off so fast.


if someone can take the time to go over our situations and try and explain each step why it's happening just so we can have an idea on what to do next time, cause honestly yes the cars started, but it kills the experience trying to start cars for 45 mins before each run. At least knowing what i need to do before each run will make things much easier and funner, we don't mind the tuning of the needles and such (it's all part of the experience), but we never know what to tweak, like I said we end up tuning all 3 for the cars to end up starting, that's probably our inexperience, but if one of you fellas can help us out on that one, it's greatly appreciated.

Thank you,

Rodi
try to check the spacing of your idle needle it should just be 1mm apart. also when starting the engine your throttle trims might be set to the maximum so the carb is wide open causing the car to take off without pressing the throttle.

if its really cold you will really have a hard time starting a nitro engine, it is best to warm it a bit, i use the car heater to warm it and after a few pulls it will start. also make sure you have primed the engine very well just make sure not to flood the engine.
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Old 03-04-2010, 09:51 AM   #20
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what are the symptoms of each needle? to know if each one is too lean or rich

High speed too rich
High speed too lean

Low speed too rich
Low speed too lean

Idle too rich
Idle too lean

and another question. Since you're supposed to do the tuning after the engine warms up, wouldn't that mess up your start-up the next time you wanna run your vehicle since your adjustments won't be good anymore?
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Old 03-04-2010, 10:24 AM   #21
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hey there kharoff , glad too see you are stiill baving at the mouth for your rc!
soo much that it keeps you out in the cold till midnight ... yeh haa ! now that's addiction!

what your experiencing is normal unfortunaly for nitro when it's cold and when they are in the break in period. i don't know why but alot of guys getting thier first rc always pick when they WILL have trouble. ( my first was in janruary, try and start a nitro at minus 20 and not get frustrated . lol )

for the first half a gallon you may need tio keep adjusting the screws a little as the motor uses to fit.
then it will stop needing ajustment as often .... now here is the thing though!!!
each day and from one hour to the next a nitro engine may seem to run differnently.
you could spend all day every day tuning your car to perfection and all that will do is make you go nuts!

the best way to deal with this is to ajust more rich, and just learn to live with the way it runs, because by the end of the tank you will see that it usually much differnet! the engine warms up and the hole chassis also gets warm and changes how the engine performs.
so if you want your truck to be super peppy and spin easy when it's cold, your motor will be sooo hot but the end of the tank , you will need a new motor before the end of summer !!!

it should be hard to keep running when it's cold, and then buy 1/4 of the first tank you should get normal idle and not stall on brakes.

as for the needles, i don't play with my needles at all once i've finished break in. for about 6 gallons of nitro, then the motor gets worn and needs adjusting.

also now you ask the right question about how th ajust the needles!
it's never set buy number of turns, always buy temperature and performance.

idle- is high or low like giving it gas or trim.
set this so when on brake motor does not stall and wheels do not spin on block.

high speed- at high throotle you want steady smooth accleration all the way up rpm band and temps should never keep going up.
to rich- lots of smoke, gurguling and sputturring instead of acceleration, low top speed.
to lean, crazy accleation then bogging , high temps, engine seems to sputer at higher rpms, glow plugs burned out .

low speed needle is important and can affect the high so recheck temps at high speed as well.
to rich, low idle speed , stalling before clutch disengages, sluggish acceleration, stall after 1 second idle, after letting go of gas idle is high then slows down
to lean, higher and higher idle speed the more it warms up, too much acceleration of idle then stumbles.

thes are just some symptoms and the more you use your truck the better you will know it's little secrets.
hope this helps, but there is no magic solution, these things have character in many ways, that is what makes them better and worse than electric at the same time.
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Old 03-05-2010, 08:58 AM   #22
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Hey guys, I'm Khar00f's cousin.
I've been following this thread and just joined the forums. Thanks to all for your input, it's very appreciated. Having taken the jump and gotten our first RC cars, it sure is nice to have access to knowledgeable and helpful ppl like you guys

I wanted to add some details to the difficulties we had Wednesday night at the parking lot to help you guys help us...

1- Sometimes the car sounds like it has a high idle, and if I put it on a block the wheels spin slowly, and on the ground the clutch is at the limit, I see the car trying to go forward but then the clutch slips and so forth. Now I checked that the throttle is not pulled at all, the trimming is correct. I tried lowering the idle, but then it sounds like it's gonna die and it does after a moment... Is that due to the low speed needle only or does the high speed needle have any influence at all at idle? What can I do in that situation to adjust the idle to not turn the clutch bell yet not have the car turn off by itself?

2- Every time I would give the car more than half throttle it would stall, and to me it sounded like it was choking on too much gas, so i leaned the high speed a little and tried again, but then it would choke with less throttle, so i decided to go the other way (richer). Doing it a little at a time, i got to a point where the car would not choke even if I gave it full throttle from standing still. At that point I stopped fiddling with the needles and decided to finally have some fun b4 calling it a night. There was blue smoke visible all the time the throttle was pulled, which I think means it's safe for the engine... Was that OK or is there a possibility I was still running too lean? How can I tell? Should I have kept richening the high speed until I get to the limit of performance drop then dialed a little back? (my car has done 5 tanks so far)

Thanks!
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Old 03-05-2010, 09:50 AM   #23
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http://www.youtube.com/watch?v=oSmMzpZM_As

http://www.youtube.com/watch?v=BJFsJ...eature=related

Vidoes I found on tuning, I think the concept is there.
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Old 03-05-2010, 10:36 AM   #24
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Thanks I'll watch them once I get home, YouTube is blocked at work :(
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Old 03-05-2010, 11:26 AM   #25
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ouch, what hobby shop did you go to ?

it was way too lean on the high speed for stalling like that!
could be due to breaking in and all but at least you are getting a fell for it and that is all you need to start then you will see how easy it is.
also get a temp gun and be sure to subtract the temp outside compared to summer.

also for idle ... it is still a tight motor so let it use in a little before perfect ajustments can be done.
and it needs to be completly warmed up to expect a good idle
and the low speed needle too rich or lean changes your idle alot
lean... high
rich... high after letting go of gas then low , or just low
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Old 03-05-2010, 12:01 PM   #26
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Originally Posted by LebThug View Post
Hey guys, I'm Khar00f's cousin.
I've been following this thread and just joined the forums. Thanks to all for your input, it's very appreciated. Having taken the jump and gotten our first RC cars, it sure is nice to have access to knowledgeable and helpful ppl like you guys

I wanted to add some details to the difficulties we had Wednesday night at the parking lot to help you guys help us...

1- Sometimes the car sounds like it has a high idle, and if I put it on a block the wheels spin slowly, and on the ground the clutch is at the limit, I see the car trying to go forward but then the clutch slips and so forth. Now I checked that the throttle is not pulled at all, the trimming is correct. I tried lowering the idle, but then it sounds like it's gonna die and it does after a moment... Is that due to the low speed needle only or does the high speed needle have any influence at all at idle? What can I do in that situation to adjust the idle to not turn the clutch bell yet not have the car turn off by itself?

2- Every time I would give the car more than half throttle it would stall, and to me it sounded like it was choking on too much gas, so i leaned the high speed a little and tried again, but then it would choke with less throttle, so i decided to go the other way (richer). Doing it a little at a time, i got to a point where the car would not choke even if I gave it full throttle from standing still. At that point I stopped fiddling with the needles and decided to finally have some fun b4 calling it a night. There was blue smoke visible all the time the throttle was pulled, which I think means it's safe for the engine... Was that OK or is there a possibility I was still running too lean? How can I tell? Should I have kept richening the high speed until I get to the limit of performance drop then dialed a little back? (my car has done 5 tanks so far)

Thanks!
you really need to know how warm the motor is getting with such cold temps out you should have a sock or foil around the head to the temp comes up because to cold is bad on the motor and will give idle troubles. also note if you adjust idle stop screw you also have to adjust the lsn equal amount the opposite direction meaning 1 hour in on idle screw means one hour richer on the low speed needle its not 100% but a rule of thumb and will be close also when first starting in such cold leave glo ignighter on for a lil while and put around with it to get motor warmed up easier but you really cannot adjust the carb until you get motor to 200 degrees Ferinheit sorry dont know it in Celcius but below that you will end up with motor to lean and blow it up i learned the hard way cost me about 3 motors
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Old 03-05-2010, 12:03 PM   #27
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ouch, what hobby shop did you go to ?

it was way too lean on the high speed for stalling like that!
could be due to breaking in and all but at least you are getting a fell for it and that is all you need to start then you will see how easy it is.
also get a temp gun and be sure to subtract the temp outside compared to summer.

also for idle ... it is still a tight motor so let it use in a little before perfect ajustments can be done.
and it needs to be completly warmed up to expect a good idle
and the low speed needle too rich or lean changes your idle alot
lean... high
rich... high after letting go of gas then low , or just low
ok, well I was getting the high idle after letting go for about 6-8 seconds then drop to constant idle, so probably my low speed was too rich... but after fixing the stalling by riching the high speed, do u think it's still too lean? How can I tell if it needs more richening w/o a temp gun?

PS: Just to clear up things, my cousins car was tuned by the shop, but not mine... My schedule and their opening hours just don't work out, I have to get out of my way to go there it's just not very convenient for me...
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Old 03-05-2010, 12:09 PM   #28
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you really need to know how warm the motor is getting with such cold temps out you should have a sock or foil around the head to the temp comes up because to cold is bad on the motor and will give idle troubles. also note if you adjust idle stop screw you also have to adjust the lsn equal amount the opposite direction meaning 1 hour in on idle screw means one hour richer on the low speed needle its not 100% but a rule of thumb and will be close also when first starting in such cold leave glo ignighter on for a lil while and put around with it to get motor warmed up easier but you really cannot adjust the carb until you get motor to 200 degrees Ferinheit sorry dont know it in Celcius but below that you will end up with motor to lean and blow it up i learned the hard way cost me about 3 motors
I guess a temp gun is really a must then... at least in cold weather and when it's our first car. Any recommendations where to buy one and what brand/model are good? Just need it to be reliable enough for the task, and not too big or expensive... I'll look around on ebay, feel free to suggest.
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Old 03-05-2010, 02:03 PM   #29
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Originally Posted by LebThug View Post
I guess a temp gun is really a must then... at least in cold weather and when it's our first car. Any recommendations where to buy one and what brand/model are good? Just need it to be reliable enough for the task, and not too big or expensive... I'll look around on ebay, feel free to suggest.

No need to get a temp gun. To get a feel for the needle, continue going richer on the high side needle until you see the performance fall off again. This will let you experience both sides. Lean it out until the performance comes back and leave. Jump the low side and do the same thing. Dont be afraid to go a few hours, it's easier to feel the big change and as long as you arent too lean (error on the side of caution), you arent going to hurt anything.

Only thing a temp gun is going to tell you is the temp. How helpful does that sound? Once you get it tuned, check the temp and then use that as a reference for later.
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Old 03-05-2010, 06:49 PM   #30
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Vidoes I found on tuning, I think the concept is there.
Thanks for those vids! Helps a lot, especially the 2nd one.
By what I remember, I can tell that the HSN was in the good running range, although it probably was a bit on the lean side of it. As for the low speed needle, it probably was a bit too lean, as the idle rpm was a little high and the acceleration was quick, not slow like in the 2nd vid when they show the rich LSN sluggish acceleration. Also I couldn't close the idle needle any bit w/o the car turning off, so i think i had to richen the LSN, and then adjust the idle accordingly.

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Originally Posted by madweazl View Post
Only thing a temp gun is going to tell you is the temp. How helpful does that sound? Once you get it tuned, check the temp and then use that as a reference for later.
I won't get a temp gun for at least a week anyways if i order one now, and i won't stop using the car cuz i don't have a temp gun... I was actually set to not getting one, as I think it'll just add another variable, and make me worry about temp.
I'll go with instinct and try to develop a feel for the sound and performance, and I'll try to stay a bit more on the rich side at least in the beginning. I'll probably end up getting one in the long run...

I think the major problem I'm experiencing is starting the engine in the cold, and changing the needle settings to try to start it. I now know better than to change any needle while the engine hasn't warmed up. Tomorrow I'll try warming the engine with a hair dryer or the car heater before starting it and see how that goes.

I have one thing I need your input on:
does what I think happened as described above (good or a little lean HSN, lean LSN) fit with a temporary high idle after a full stop, followed by a drop to constant idle after a few seconds?
From memory I think I read this is due to LSN being too rich
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