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A bad day at the track is better than a good day at the office...

A bad day at the track is better than a good day at the office...

Old 08-31-2009, 02:04 PM
  #16  
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i had a throttle Pot in my old 3pk Black let go and do similar thing's like go 1/4-1/3 throttle with the TINYest of imput on the remote....even with the expo -100 it was still overly twitchy....after Many of call's to futaba i finally got a tech that listened to the whole story of how i was testing and confirming it was the radio and not the gear....eventually he came to the conclusion that was the only thing that would affect what i was getting....he said i could send it in and get serviced....but i neglected to and went and bought a new Super body and everything was Kosher.
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Old 08-31-2009, 02:19 PM
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Sounds like a badass weekend of racing to me hehehe.
I have the N21BF also and run a larger cooling head on it.
I had to gear up on size on the CB also to get it run out...if not I would have no top end at all with that engine. They do run hot though...with the larger head I am around 245ish but its a good club engine for sure.
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Old 08-31-2009, 03:10 PM
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I always find your stories very entertaining Brad..sorry it was expensive
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Old 08-31-2009, 04:39 PM
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Originally Posted by supralative
Sounds like a badass weekend of racing to me hehehe.
I have the N21BF also and run a larger cooling head on it.
I had to gear up on size on the CB also to get it run out...if not I would have no top end at all with that engine. They do run hot though...with the larger head I am around 245ish but its a good club engine for sure.
I don't think I have any lack of RPM on this one... it is modded by Hotmods. So far it is pretty good and it isn't even really broken in yet.... we'll see how much life I get out of it.
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Old 08-31-2009, 04:39 PM
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Originally Posted by Jaz240
I always find your stories very entertaining Brad..sorry it was expensive
Stuff happens. Oh well.
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Old 08-31-2009, 05:39 PM
  #21  
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Been there done that but luckily without the motor go boom part. Sounds like a few of my days actually.
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Old 09-04-2009, 10:27 AM
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Originally Posted by DOMIT
Or is it?

(Alternate title: Rookie mistakes!) Hopefully y'all can at least get a chuckle at my expense... and it WAS expensive, as you will soon see!!!

I had a fairly unfortunate chain of events (mostly self-created) that ended up being relatively expensive over the past week... We spent the past week getting ready for the RC Pro South round 3 race in Bossier City.

Since I was down to one good engine and wanted to try something different, I was breaking in a new modded Novarossi BF21 Limited. During break in we were having a little trouble getting it to idle well (just a VERY tight engine with a finicky tune... no big deal...) Unfortunately, every time I touched the throttle it would kill it also, so it was a bit frustrating.

My buddy Ron noticed that just a TINY amount of trigger was pulling about half throttle, so we thought the throttle servo was going bad. (It wasn't, but more on that in a bit...)

I bought a new Hitec 7955 TG, put it on steering, and put the 5955 that I've been running for steering on throttle. The old throttle servo was a Futaba 9351... so of course I had to reverse the the servo on the transmitter. (once again... more on this in a minute...) Reversing the servo was the only change I made on the transmitter... (Rookie mistake #1! Remember this one...)

Changing servos didn't make any difference... the potentiometer on my transmitter for throttle is evidently going bad. (Hmmm... maybe my finger isn't as bad as I thought it was!)

So, given that I had to work Friday, I got to the track late Friday evening and continued to work on breaking in that engine, which was intended to be my backup. It was getting better, but still very finicky on tune, and like most engines that you're breaking in, too much throttle will make them die. A little bit frustrating, but... it was coming along. NO practice time for me Friday, unfortunately, just running up and down the field in the back trying to break in and tune.

Saturday morning I tried to practice with / track tune the new engine... boggy, flameouts, and just generally not a good practice session- I made a whole 3 laps in practice. Not good for me- I'm slow to learn a track layout.

A quick engine change before round 1, and I was good to go... everything was back to normal, and round 1 became my practice session. I had a bad run (of course... 3 laps of practice? I need AT LEAST a fuel bottle to learn a new track layout... I'm slow to pick up on it.)

They called me done a little late, so I couldn't make the turnoff and simply pulled it off the end of the straight to not hinder other traffic...

My pit guy was pitting 2 of us, so he went down and temped me, and put my truck back down... I couldn't see him very well, and I THOUGHT since he put it down he had shut it off... so... (rookie mistake!) I turned off my radio and walked off the drivers stand. (I know better than that... I simply wasn't thinking... and he had NOT shut it off...) (Rookie mistake #2!)

Remember Rookie mistake #1? Now lets add Rookie mistake #1 + Rookie mistake #2:

I previously had set (as recommended) my radio failsafe to full brake... well, the receiver doesn't know the servo is reversed, only the transmitter does. So... when I shut off the radio, it of course went to failsafe mode, just like it is supposed to- in this case... FULL THROTTLE. The result, despite the best efforts of the marshal, was a blown VSPEC. (Like I said... expensive mistake.)

Now I'm down to 1 engine, and it just starting to break in... I got some help tuning from a guy who runs modded Novarossi engines, so we got that fairly well sorted out... but due to the transmitter issue it was bogging every time I'd touch the throttle, so I was having to "blip" to clear it every time I wanted to accelerate at all... pretty hard to drive like that! That + still not knowing the track well was of course hurting my driving. (Not that I can drive that well anyway...)

So, after round 2 I decided I had some time, I'd see if I could do anything to fix the radio. (Another bad move...) To keep it short, I'll just say I ended up breaking the antenna lead on my Spektrum module. Now I'm without a radio.

Fortunately Josh Glancy had a spare DX3.0, (Thank you VERY much for the load of the radio Josh!) so I bound it to that radio, set it all up, and was able to run the rest of the weekend with a borrowed radio- but of course it feels different from my M8, and the response time is somewhat slower, so everything was different, and I'm back to continuing to learn a track with a truck that now drives completely different.

The end result was $300 for an engine (VSPEC + ceramic bearings) and probably $10 for the antenna assembly... and 7th in the C-main. (I have to admit I probably would not have done much better under perfect conditions though.) Frustrating, but I still had a good time.

Ok, laugh away!
Domit,

I've been having some problems with the Futaba radio in my buggy lately and finally decided to swap it out for an Airtronics that was in my monster truck. Thanks to reading your post above, I tested the failsafe position after the radio swap and sure enough when I turned off the transmitter the throttle opened! I had to re-bind the radio to the receiver but now I'm good and possible disaster averted! Thanks.
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Old 09-04-2009, 10:44 AM
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Originally Posted by LabRat99
Domit,

I've been having some problems with the Futaba radio in my buggy lately and finally decided to swap it out for an Airtronics that was in my monster truck. Thanks to reading your post above, I tested the failsafe position after the radio swap and sure enough when I turned off the transmitter the throttle opened! I had to re-bind the radio to the receiver but now I'm good and possible disaster averted! Thanks.
I'm happy to know that someone else could learn from my mistake... glad it helped.
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Old 09-04-2009, 10:48 AM
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Originally Posted by DOMIT
I don't think I have any lack of RPM on this one... it is modded by Hotmods. So far it is pretty good and it isn't even really broken in yet.... we'll see how much life I get out of it.
Mine is a Jim Hottinger set up also.
I find the RPM band similiar to old OS RG engine. Good club motor but needed to extend out the top more so I went up on the CB also on it.
I am going to replace the bearings in the N21BF and use it daily and save my two RB's for the major races.
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Old 09-04-2009, 02:40 PM
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Happened to a racing buddy a while ago. His throttle servo crapped the bed and I lent him mine, which required reversing. He didn't re-bind and OF COURSE it failsafed upside down at full RPM. It wasn't immediately obvious that it was pooched, but later on he found out that a glowplug coil had broken and marred the side of the piston/sleeve.
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