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  1. #1
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    Quick tuning question

    Well guys I am getting better at tuning my t-maxx thanks to you lot. But today I encountered a slight running problem I could do with some advice with. Ok my t-maxx would accelerate to about 20mph and would then make a gargling sound and find it hard to go any faster. Is this what you call bogging? The temps seemed ok at about 210 indicating too rich a mixture but then when I opened up the throttle there wasn't a huge deal of smoke so can it really be running rich? It seemed to accelerate well up to 20mph plus the pinch test seemed about right (about 4 seconds) so I think the lsn is ok. Question is what fine tuning do I need to do with this?
    As I say i am getting a lot better with tuning and I think I am getting it tuned in roughly the right area, just need to learn the fine tuning bits now! lol! Thank you everyone.

  2. #2
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    Hi
    I'm no pro but i guess even running your maxx rich for longish periods at wot would raise your temps to 200+
    If you lean the mix out i bet it would raise your mph and stop the bogging. It may even lower your temps as your not having to fully open throttle for getting the same mph eg 20mph ?
    Also i maybe wrong but i think anything between 210-270 is normal ? Please correct me if i'm wrong anyone
    Last edited by KILO-DELTA; 09-10-2009 at 02:33 PM.

  3. #3
    RC Turnbuckle Jr. Nitronaught's Avatar
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    Try going over this thread, especially the part of using the pinch test for your LSN.

    Don't just tune 1 needle, they both work together as a team...

    http://monster.traxxas.com/showthread.php?t=334452
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  4. #4
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    Yeah thank you guys i've printed that thread off, should come in handy in future. However it doesn't really tell me how to deal with the bogging issue, if it is a bogging issue that is.

  5. #5
    RC Turnbuckle Jr. Snook Man's Avatar
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    There are two types of bog:
    A gargling sound while on throttle usually indicates the tune is too rich = Rich bog.
    A stuttering sound while on throttle usually means too lean = Lean bog.

    A sound like Chewbacca makes when decelerating usually indicates a lean LSN = Detonation.
    No slipper/tall gearing/power = broken parts.

  6. #6
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    snook haha..
    T-MAXX 3.3 ACNCM BBcHaSI...Jato 3.3..33the Best sb

  7. #7
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    Two types of bog? Lol! Wel that's just great that! lol! Hmm ok well please watch this video clip, this is the sort of sound mine makes although I don't think there's as much smoke plus as i say my temps are about 210 which I assume is a tiny bit low? http://www.youtube.com/watch?v=H43EtVKPMM0 Also mine is making that noise at a higher speed then the truck in this video clip. But the sound is definatly the same.

  8. #8
    RC Turnbuckle Jr. Snook Man's Avatar
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    That is a lean bog...Richen the HSN.
    No slipper/tall gearing/power = broken parts.

  9. #9
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    Thank you snook man i'll give that a try. Cheers!!

  10. #10
    RC Turnbuckle Jr. Nitronaught's Avatar
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    Quote Originally Posted by alans27
    Yeah thank you guys i've printed that thread off, should come in handy in future. However it doesn't really tell me how to deal with the bogging issue, if it is a bogging issue that is.
    Like Snook said it is s tuning issue, and the links in that thread will get you through the entire process. click on the links and it will show you how an engine should sound when tuned, when lean and when rich...

    The thread I refer to works fairly well for people who are new to nitro....

    Remember turn those needles in no more than 1/8th increments and always do a WOT pass when making any change. Never tune with a full tank, it's all in that sticky... It's been viewed over 38,000 times so I guess it has some purpose...

    Good luck...
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  11. #11
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    the lean bog you can tell usually when hitting the gas hard like trying to do a wheelie and the truck wont move and its making a sputter/bog sound, or when it hits second it wont go into second and start to stutter/bog, then you have to richen the HSN..

    a rich bog will have lots of smoke and gas, when you hit the gas hard there will be alot of smoke and the truck will move slowly and then the engine will start to clear.. sometime wont shift into second but it wont make that stutter sound when it hits second it will just stay in first..
    T-MAXX 3.3 ACNCM BBcHaSI...Jato 3.3..33the Best sb

  12. #12
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    Thanks Rich that makes a lot of sense. It's just odd that it's lean bogging and yet the temps aren't that high. Can this happen?

  13. #13
    RC Turnbuckle Jr. Snook Man's Avatar
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    What was the ambient air temp when you were running? I see that in Liverpool today the temp was 59F
    Colder air temps require a richer tune. In cold weather a sock or aluminum foil wrapped around the cooling head is sometimes needed to help raise engine temps to a normal level.
    No slipper/tall gearing/power = broken parts.

  14. #14
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    Blimey Snook man that is serious dedication! Lol! I don't know how hot it was today, had my shorts on so it wasn't that cold. Think it was about 20 degrees celcius according to my car.

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