2200 Combo running hot !
 

Here is my setup, 2200 mmm combo,gearing on mbx-5t is 46 and 14 pinion running 5s 35c pack with rulux 1\2 ups and lpr bowties.Temps after 5 mins were esc 98,batts were 95 and then the motor was 186? Checked it 3 more times to make sure and was fairly stunned. Way too hot it seemed.Looked over the drive train for binding and such,but everything was free.I just rebuilt this whole truggy ,diffs bearings and cvd's,new wheels and tires new batts and the mmm was run straight out of the box.Is my gearing wrong? Do I need to lower my settings for timing to low from normal? Kinda scared to run this anymore due to the heat. I thought this combo was gonna be much cooler running.Any suggestions are welcome.I wanna have some fun,but not worry about frying this bad boy.

Yes, set the liming to lowest, that may help. Also make sure all of your motor connections are tight. Have any other motors to try?

The gearing sounds fine. How was the performance when it was running? Anything binding? Is it possibly unloading letting the motor spin up too high? Gear mesh ok? Pinion secured well on the shaft?

Those are just some of the things I could think to check that could contribute to your motor getting that hot so quickly.

A buddy of mine was running his MBX5T with a Neu 2200kv, MGM 16018 and 6s2p A123 (around 5s lipo). His truggy must have been heavier than yours (Battery wheight around 900gr/almost 2lbs) and at the end he used a 13t pinion. During hot sommer days the ESC shut down due to thermaling and the motor reached up to 85°C/185°F. He used crimefighter tires also on rulux wheels.

Problem is the motor revs too high with 5s (around 40700rpm). A nitro motor revs between 30000-35000rpm. With a 14 pinion your gearing is 1:15,11 and without ballooning your top speed should be around 74km/h / 46mph. Way too fast for a truggy on a track and when pushed too hard temps will be high.

Your best bet is to decrease load on your motor and use smaller pinions. Cut holes in your body to increase airflow. I would start with a 12t pinion which should reduce speed somewhat above nitro truggy level.

I have an Mbx5 buggy converted with 36 60 medusa ,mmm same gearing and runs 40ish on 4s and is almost cold to touch after running for 10 mins.I have run the same 5s pack in that one too and it did get a little warm,but not that hot like the mmm combo did, different wheels and tires though,and of coarse,lighter.I need some more mod1 gears to try gearing up or down,kinda seems like it could be geared up with everythingelse being so cool and all,but I'll try both ways. I reset the timing to low and will give that a shot today and will try all that was suggested .If it continues to run hot,I might have to pull it and try a 70 or 80 can medusa,they seem to run very cool and strong.And yes the 2200 runs very well indeed,with the front end pulling up anytime you want to, real torque monster.I did do the diffs at 7k 10k 3k,not so sure this is right for a truggy with this kind of power,but turns and burns well enough,with the front unloading a little when you put full power to it.

Tried it with timeing set to low,and it cooled things down to 160.Next I'll try bigger pinion and smaller pinions,still lots of torque but slow top end,about 34mph.

40k rpm isn't too high for the Neu though [?]. Thought they were safe to 50k.........

160 isn't bad for temp. Play with your gearing and you should find the "sweet spot"

Thanks for the help guys,about to order some different sizes from Mike.I do have a 12 tooth I'll try that next.then a 15 and 16 too.I love these Truggy's!:yipi:

airflow - do you have a hole in the windscreen?

Ya I think these motors need some airflow around them. So have you been able to consistently get 160 with the timing low? or was that just a shorter run? I know the timing for me means about 1.5mph down for each one so if you went from normal to low you probably lost about 3mph which isnt a bad speed for those temps.

Yeah...my first guess would be to check the drivetrain and make sure there isn't any binding. Pinion mesh could be off too.

Running a nitro boby with cutouts in it.Only had time for 2 back to back runs today and both runs read pretty close to the same temp.Here's a couple pics.

put much heavier oil in the centre diff. i bet your centre diff is unloading and making the motor rev out harder that it should be, look for the front wheels panning.

I know a billion of my friends have complained about hot motors on their 3 diff cars, and every time it's because the centre diff unloads too easily and the motor revs super hard with minimal load on it.

I re-checked the drive train today for any binding,but all looks and feels well .As far as pinion mesh.I set it with a piece of paper between the two gears and loc tited it down,and it's really holding the mesh well.I'll re-examin all those things just to make sure though. Pulled up the castle link again and went thru it to make sure all was well there too.Gears from Mike should be comming soon.With temps down in the 160 range I won't be so afraid to test it for a longer period now.Building these up has been made pretty easy with all the niceity's being sold now from savvy companys like Castle and RC Monster....it's the tuning part that takes some skill to bring it together and really enjoy it all,and a gratefull appreciation for those with so much knowledge and experience. (oh yeah...and lots of cash !):lol: