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Old 01-24-2009, 09:47 PM   #1
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Default Got the 8ight converted! a few questions, pics and observations.

I finally got everything to put my brushless 8ight together. I guess it's not really converted since it was never nitro. But it was the original kit, not the 8ight-E. It seems cheaper to purchase everything and convert an original 8ight than it is to buy the 8ight-E. Plus, I wanted the MMM combo not the Xcelorin. But I digress. Here's my pics:
Got the 8ight converted! a few questions, pics and observations.-pict4002.jpg
Got the 8ight converted! a few questions, pics and observations.-pict4006.jpg
Got the 8ight converted! a few questions, pics and observations.-pict4008.jpg

Holy crap it's fast with 5S. This Zippy Rhino pack is great (so far). I got the turnigy accucell 6 charger which I'm impressed with as well.

Got the 8ight converted! a few questions, pics and observations.-pict4005.jpg

I haven't done all the touchups yet, there's still a few wires I'll be cleaning up yet and I'll probably be getting an 8ight-E body once they're a little more available. And yes, don't laugh, I'm aware of the goofy battery setup. The 5S batt won't fit with the battery tray in the Losi conversion kit unless you have the 8ight-E body, so I put down industrial strength velcro on the chassis and battery. It hold VERY well. A little too well. I practically tear the chassis out to get the battery out to charge it. When they say industrial strength they aren't kidding. I'll probably see how I can incorporate some straps but so far it's very sturdy, even after two turnovers (I'm still learning how to deal with this much power Name:  eek_.gif
Views: 353
Size:  1.2 KB) plus it never rubs against anything when attached to velcro.

Anyway, I had a few questions for you guys that have done the conversion:

First, I've heard you can quiet things down a bit by getting a nylon spur. I'm used to using nylon or kevlar from my old Losi XXX. Steel seemed like a good idea when I was building the kit but wow, it's loud. Is nylon less durable than steel? The braking probably puts a lot of stress on the gears so if it's not durable then I'd probably rather go with loud than unreliable.

Also, I've been having a bit of trouble with my pinion comming loose, usually after 10 minutes or so of running. I crank the screw down pretty hard but it keeps comming loose. Is there some sort of secret with keeping it on that I'm missing?

Last, my old brushed orion revolution was pretty smooth at low speeds and startup from stop. This MMM/2200kV setup isn't so smooth. I set the motor timing lower on the Castle link software with helped but it's still pretty rough. I'm getting used to it but wondered if there's anything else to help the startup cogging that I'm experiencing. I know that this is sort of intrinsic to an unsensored setup but I've heard others say theirs is "butter smooth" and mine certainly isn't. I'll probably post on the Castle thread as well to see if they have any tips.

A few observations, 5S provides awesome power, I wouldn't go 4S personally. I know for racing some say 4S is the key but as long as you can control your throttle finger I don't see why. Frankly, I plan on purchasing a 6S next. Power for the win!! Also, this mamba monster runs COOL! As does the motor and battery. Using an infrared thermometer the hottest I've gotten them after a little over 20 minutes of hard run time is a little over 100F (motor). Granted, it's about 40-50F out when I run so the summer might be different. We'll see.

Last edited by Ryandrea; 01-26-2009 at 08:14 AM.
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Old 01-24-2009, 10:45 PM   #2
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Quote:
Originally Posted by Ryandrea View Post



Anyway, I had a few questions for you guys that have done the conversion:

Also, I've been having a bit of trouble with my pinion comming loose, usually after 10 minutes or so of running. I crank the screw down pretty hard but it keeps comming loose. Is there some sort of secret with keeping it on that I'm missing?

Last, my old brushed orion revolution was pretty smooth at low speeds and startup from stop. This MMM/2200kV setup isn't so smooth. I set the motor timing lower on the Castle link software with helped but it's still pretty rough. I'm getting used to it but wondered if there's anything else to help the startup cogging that I'm experiencing. I know that this is sort of intrinsic to an unsensored setup but I've heard others say theirs is "butter smooth" and mine certainly isn't. I'll probably post on the Castle thread as well to see if they have any tips.
Can't help with the nylon spur (didn't even think they made something like that for 1/8 scale stuff) but for the pinion, make sure to use loctite, or it'll come loose every time.

As for the cogging, try setting the startup power to "High". That should help. It always did on my crawlers anyway.
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Old 01-24-2009, 11:55 PM   #3
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Default Some things that might help

I have been running the 46t plastic Kyosho spur that comes with the RC Designs kit and have had not problems at all. I have used the same spur for about a month now. If you are using metal on metal and find it too loud, try the Losi pinion. For some reason their pinions are quieter when used metal on metal.

My pinion came off a few times in the beginning. A moderate amount of blue locktite did the trick.

if you are racing then 4S is more than enough for most applications. Some guys are running 5S with a 1800kv motor, or a 6S with a 1300 to 1500kv motor with good results. you will get longer run times and cooler temps with a higher voltage setup. For me a 4S with a Medusa 2000kv is as fast or faster than anything at my track.
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Old 01-25-2009, 01:27 AM   #4
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4s with either Castle motor is plenty... but more power is fun

The Kysoho plastic gear does sound better and it's reliable as long as the gear mesh stays correct.

As mentioned... threadlock the pinion set screw, and I also use a little on the motor screws.

The MMM is plenty smooth but it is for racing, not crawling. It might not be able to start out creeping super slow and smooth every time, but that's not what you do on the track. In any case... it's certainly smoother than a nitro

Temps do run much higher in the heat of summer, compared to running in the 40's... and racing will create a little more heat than just bashing . These things do run cool in cold air. I ran a 30 min race one time in cold weather and the motor and esc both temped barely over 100
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Old 01-25-2009, 08:38 AM   #5
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Hey guys, I have an older mbx from ofna and would like to switch to the kyosho spur. will it fit? and where do i purchase one?
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Old 01-25-2009, 09:37 AM   #6
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Hey guys, thanks for the tips. Good idea on the loctite, I should have thought of that before. I don't know what I was thinking Name:  loco.gif
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I think I'll give the 46T Kyosho pinion a try, I only have breaking and punch control on 50% (default) so hopefully that will mitigate the strain on the drivetrain.

I'll have to give the "startup power" option a try too. I think as I dink with the setting more I'll get what I'm looking for. It's great that castle provides options to do that. ESC's are more like mini-CPU's now a days. Things have changed a lot in the last few years.
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Old 01-25-2009, 10:32 AM   #7
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turn the puch control up to 20%-30% that helps with the coging
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Old 01-25-2009, 10:50 AM   #8
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That battery wont fit in any of the battery trays anyways. 184x51x41, WOW. Try a smaller Mah. Like around 4000.
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Old 01-25-2009, 11:11 AM   #9
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Hey,

Your next battery should be the zippy-h instead of the rhino they will fit in the battery tray perfectly. tHey arent that much more money then the rhinos.


Set your punch control to 20-40% for racing. Starting power to low. Timing to lowest. MAke sure you have good solder connections from the motor to the esc. that should help the cogging.
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Old 01-25-2009, 11:35 AM   #10
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Quote:
Originally Posted by legend15x3 View Post
Hey guys, I have an older mbx from ofna and would like to switch to the kyosho spur. will it fit? and where do i purchase one?
Does this car use 4 bolts and nuts to hold the spur onto the outside of the diff case, or is the spur gear an integral part of the diff. Some of the Ofna's use a bolt on spur that is not part of the diff itself. If yours is this type, the kyosho spur will not fit. On the other hand you can probably modify a Monster GT spur to fit as I did with a traxxas spur about 4 years ago. You can kind of see it in this piture

http://kufman.com/img/Stuff/car_pics...or%20mount.JPG

Does your center diff look like the one in the picture? I have attached a picture of my modified traxxas spur.
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Got the 8ight converted! a few questions, pics and observations.-ofna_spur.jpg  

Last edited by kufman; 01-25-2009 at 11:49 AM.
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Old 01-25-2009, 05:05 PM   #11
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whos conversion did u use and how was the build etc??
have a losi 8 t im wanting to convert,kinda put it on the back burner but..
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Old 01-25-2009, 05:15 PM   #12
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Its the losi conversion.
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Old 01-25-2009, 05:28 PM   #13
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kufman,

yes my spur is like that. I found one i think on rc monster. But just order a few pinions so will go with the spur i have now for now. But wonder if i can put 48 pitch on that?
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Old 01-25-2009, 05:40 PM   #14
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Quote:
Originally Posted by legend15x3 View Post
kufman,

yes my spur is like that. I found one i think on rc monster. But just order a few pinions so will go with the spur i have now for now. But wonder if i can put 48 pitch on that?
You could probably modify just about any gear to work. Depends how creative you want to get
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Old 01-25-2009, 06:45 PM   #15
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Also check that the pinion gear is actually engaging the flat of the shaft. My buddy had a nightmare keeping the pinion on (same motor as you) no matter how much loctite, until he realized he was putting the pinion on so far that the set screw was just catching the edge of the shaft where it is full round. Moved the pinion 1mm out so the set screw was fully on the flat, tightend it up, all was well.
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