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Top speed setup help. What motor for momba monster x

Top speed setup help. What motor for momba monster x

Old 08-03-2018, 02:02 PM
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Default Top speed setup help. What motor for momba monster x

I have an associated tc4 that Iím trying to hit over 100mph. I first had a hobbywing xr10 pro 160a ESC with a hobby wing 3.5turn 9500kv motor. I hit 77mph on a 2s battery with a 30pinion and a 66t spur with 30 degrees of timing on the motor and 20 for turbo and 20 for boost. I then installed a 45tpinion and a 49t spur and the ESC blew as soon as I hit full throttle. I figure I needed an 1/8 scale ESC so I bought the castle momba monster x 2s-6s ESC. With my hobby wing 2.5 turn 2pole 540 size motor on 2s this ESC goes into overload/over heat mode right away after less than a full pass. Whatís happening? With my fantom 8.5 turn motor I hit 55mph on 2s and 75mph on 3s. With my reddy m3 5.5t motor I hit 82mph on 3s but the ESC goes into over heat mode and shuts off after 1 short run of only maybe 5seconds of full throttle.

Any help would be appreciated.
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Old 08-03-2018, 10:33 PM
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You are overloading your motor and esc with those high gearing(3.0fdr to 5.5fdr)... At 2S you might be able to do 85mph with a tc4 (2.5t/3.5t) at 7.9fdr , but no more due to amp load caused by the heavy tc4. You can't gear these mod 2.5's any higher or they will toast your esc in no time . You will need to go to 3S/4S or above to reduce the high amp loads, but with motors that were built for high voltage like 550 motors(not 540).... At 2S you might do 100mph in a 2wd dragster or pan car with a 2.5t or 3.5t motor(5.5fdr to 6.0fdr), but you will need to wax the car thoroughly, and try to run on a day with no wind outside....Good Luck....
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Old 08-03-2018, 10:42 PM
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I just got a 3s and a 4s battery from smc. I also bought the momba monster x esc because I know lots of the people run them in there 1/10 scale Turing cars that are hitting 120mph+ usually on 3s or 4s Lipo. I just want to know what exact motor I should run and what size pinion and spur gear I should run.
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Old 08-03-2018, 10:57 PM
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I got my tc4 4S with a novak hv 4.5 motor geared at about 5.4fdr but I don't do speed runs: it might go 75mph but very easy on my motor/tekin rx8 esc combo... I can only guess that the speed run guys will use a much more powerful motor geared at around 4.5fdr or so to get over 100mph....
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Old 08-04-2018, 09:42 AM
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Originally Posted by bertrandsv87 View Post
I got my tc4 4S with a novak hv 4.5 motor geared at about 5.4fdr but I don't do speed runs: it might go 75mph but very easy on my motor/tekin rx8 esc combo... I can only guess that the speed run guys will use a much more powerful motor geared at around 4.5fdr or so to get over 100mph....
what is fdr and how to I calculate this.?
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Old 08-04-2018, 11:58 AM
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(Spur divided by pinion) X internal ratio = FDR....
You had : 49/45 x 2.5 = 2.72 fdr (not good for 2.5t)...
You also had: 66/30 x 2.5 = 5.5 fdr (not good for 3.5t)...
​​​​​​The tc4 has 2.5 internal ratio... My 3.5t novak is geared at 8.40 fdr and running cool... I gear my 2.5t at 9.98fdr for racing.... No way to run these motors at 2.72fdr to 5.5fdr without cooking the esc: show some love to your esc and stay above 7.9fdr....
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Old 08-04-2018, 12:13 PM
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Originally Posted by bertrandsv87 View Post
(Spur divided by pinion) X internal ratio = FDR....
You had : 49/45 x 2.5 = 2.72 fdr (not good for 2.5t)...
You also had: 66/30 x 2.5 = 5.5 fdr (not good for 3.5t)...
​​​​​​The tc4 has 2.5 internal ratio... My 3.5t novak is geared at 8.40 fdr and running cool... I gear my 2.5t at 9.98fdr for racing.... No way to run these motors at 2.72fdr to 5.5fdr without cooking the esc: show some love to your esc and stay above 7.9fdr....
but im not racing this and Iím just trying to do top speed runs. Also I have the momba monster x esc. Which is a 1/8 scale esc for up to 6s Lipo batteries. I know lots of the top speed guys with 1/10 touring cars run this esc and all hit 120mph+ on 3s-4s batteries. I just donít know what motor or gearing to run. But Iím pretty sure they are gear the hell out of the motors and run almost 1 to 1 gearing where the pinion is almost the same size as the spur gear which is what Iím doing as well. I just feel like I donít have the correct motor ps because all my motors are 540size 2 pole motors for mod 1/10 scale racing.

I still ill want to know what exact motor I need to buy.
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Old 08-04-2018, 12:36 PM
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I know the guys doing speed runs only run 1/8th+ motors like the new motiv or castle 2028(1/5th) , but there is no way to know if they will fit your tc4, and you will need to switch to 32p gearing, which will limit your gearing options...It might be best to PM someone who's been doing speed runs with a tc4 for more tips... Good Luck....
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Old 08-07-2018, 12:55 PM
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i just bought a castle 1406 5700kv 4 pole motor. it should be here in a few days. going test it out on 3s.
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