this is getting very old very fast (overheating) PLEASE HELP!!

[09 lex 250]

ok so i just get done running the car in a local race today and through out the entire time i could not get my car under 200 degrees in a 6 min heat! i am currently using a lrp combo/sxx tc spec with a x12 7.5 motor. i first was at the fdr perfect and motor was comming off at 210!! then i dropped to a 19 and it shed only 10 degrees. my gearing is 84/21 and 84/19.i inspected the car entirely and the only thing that is getting hot is the motor and everything else that surrounds it. lrp settings on the speedo are 1/2/2/0.motor insert is standard at 4 dot. can anyone please explain why this is happening? my old b44 use to come off at the track around 145-150 all day long with the same motor bit a sphere tc this was sold about 5 months prior to getting my bmax.i read somewhere on this forums about people having excessive heating issues and i totally do not know what to do and do not want to touch my car untill i hear some advise from you gurus that have actually had the same issue and have resolved it!

thank you and please heplp me with this i have a major race in 3 weeks and do not need this issue again when i go run!!

thanks in advance

[CODMAN]

Lex, have you tried that motor in another 4wd buggy with similar FDR? Because it could be your motor (even if in the past it was OK). Or try your current setup with a different (similar) motor? I think it's worth a try to see if you hit similar temps. Obviously, with the motor removed, do you feel any binding in the drivetrain? That needs to be checked...I'm currently running a Mamba max 5700kv system (from what I know roughly equivalent to a 6.5T-7T sensored motor) and geared 84T/22T and my temps are coming off at 170ºF in the summer heat here (yes, there is heat in Canada...), Although I do have a heatsink and fan setup on both motor and ESC...In all honnesty, I find your temps way high for a 7.5T with that gearing... Although the LRP motors are known to run hot...Hope you find the problem!

[samd]

Lrps do run on the hot side, but they do have a higher temp rating then other makes. Ok to 100degC which I thinks around 215degF

[Yardeeee]

I'm sorry I can't be more help on this as I race for Novak and have never had an issue with heat, but I have a friend who uses an LRP X12 6.5t in his BMAX and after every race his motor is always scorching hot. I do wonder whether it is the standard timing setting which is maybe just a bit too high and causes excessive heat, with the BMAX being such a heavy car?

I run a 5.5 Novak Ballistic on 21/87, I have never used an 84 spur but when I first had my Yokomo, I did always find that the gearing options with an 81 spur used to make the car run hot which made me standardise on 87 for the past 12 months...

Hope you find a cure!

[DCM]

your not running a stock spec motor timing profile on the esc?

[09 lex 250]

thanks for the replies everything is stock settings on the timing on the motor and on esc the problem has to be in the center housing! ive tried everything you can think of.plus when it starts getting hot the slipper comes loose for no reason aas well this is getting very frustrating and have never had any issues with this car up untill now so can someone tell me how to free this whole center gearbox up and stop my slipper from comming loose randomly? ive read threads on this forum but cant seem to understand because one says do it this way a d visa versa its not like i can just ru to the hobby store and get new parts at anytime any help would be greTly appreciated

[DCM]

you need to read your manual

MODE.3 (Dual ADPCmax - „Boost“): the „Boost“ adjustment is LRP‘s active motor timing system, depending
on many different factors (current, throttle position, RPM, etc) the software calculates the perfect commutation
and timing. As a rule of thumb, slower motors require higher „Boost“ settings then faster motors!

As you are running mod, you will need to turn the timing down on your esc...

[CODMAN]

Lex, what is coming loose? The nut for adjusting the slipper spring? Or the small phillips screw holding the outdrive in place?

Originally Posted by 09 lex 250

thanks for the replies everything is stock settings on the timing on the motor and on esc the problem has to be in the center housing! ive tried everything you can think of.plus when it starts getting hot the slipper comes loose for no reason aas well this is getting very frustrating and have never had any issues with this car up untill now so can someone tell me how to free this whole center gearbox up and stop my slipper from comming loose randomly? ive read threads on this forum but cant seem to understand because one says do it this way a d visa versa its not like i can just ru to the hobby store and get new parts at anytime any help would be greTly appreciated

[09 lex 250]

the screw hols and is fine when i checked it it is the nut that is getting loose im also gonna replace the bearings to some quality ceramics for the slipper housing to see if it helps plus its always good to have especially in that area of the car

[CODMAN]

Why don,t you "blue locktite" the threads? Should keep it from getting loose for nothing. The slipper bearings are the only cheap thing I found on the car! I replaced them with good quality ACER sealed bearings and kept the originals for backup (in case one fails). They are anything but standard size, so having a backup made sense to me. But I never had any heating problems there... And nothing has ever come loose (so far).For the heat issue, I still think you should try the motor in another car and see how it does. It could be overheating for no good reason...

Originally Posted by 09 lex 250

the screw hols and is fine when i checked it it is the nut that is getting loose im also gonna replace the bearings to some quality ceramics for the slipper housing to see if it helps plus its always good to have especially in that area of the car

[johnnygibbon]

a lot of us run bmaxs at our club. so we no what your saying.
they are a heavy car which apparently will in crease temp
we all generally run 6.5 or lower with 87 tooth spur and 20-23 pinion
these cars run hot whatever you do. cut big holes in ya shell. it helps.
some people run motor and or esc fans. i run neither. and its hot but ok so far.
the slipper issue is common. locktight your slipper screw. and wind ya slipper up TIGHT. and get some spare diff gears. not that they wear to quick. i race weekly and replace them every 6 months or even longer sometimes.
basically the bmax is a hot car whatever you do . but its worth it
also get a carbon shock tower. bombproof

[Matt Airbrushing]

If the slipper is coming loose then it could be a contributor to the heat problem as the motor may be overeving with the slipper loose.

It may seem counter intuative but sometimes gearing up can make things run cooler.

Otherwise try and get more airflow over the motor, with a scoop in the body or cut out the windows.

[matdodd]

Id say it would be worth gearing up and seeing if that helps, I run a Trinity Nemisis 5.5 on 19/84 with an LRP TC spec speedo on 1-3-2-0 and its hot but no where near that hot!

Also strip the slipper down and clean up the plates and pads, making sure the pads arnt to thin as the plates can bind on the spur! then check the plate with the pin slot drops over the pin easily and if it doesn't take a small file to it till it does. since I did that, my slipper has been far more consistent

[09 lex 250]

Originally Posted by DCM

you need to read your manual



As you are running mod, you will need to turn the timing down on your esc...

the settings are 1/1/1/0
the motor comes with -10 timing already inserted and that is whats in there now!

i am very familiar with lrp speedos and their manuals

[09 lex 250]

well figured out the overheating issue which is great!! now i gotta keep the slipper from comming loose during a run on the track i tried some threadlock but still came loose


any suggestions?

[matdodd]

Originally Posted by matdodd

Id say it would be worth gearing up and seeing if that helps, I run a Trinity Nemisis 5.5 on 19/84 with an LRP TC spec speedo on 1-3-2-0 and its hot but no where near that hot!

Also strip the slipper down and clean up the plates and pads, making sure the pads arnt to thin as the plates can bind on the spur! then check the plate with the pin slot drops over the pin easily and if it doesn't take a small file to it till it does. since I did that, my slipper has been far more consistent

Have you checked what I said above?
What was your overheating problem?

[09 lex 250]

the rear tranny was binding and the center housing. yes i tried blue threadlock but after a few runs it started comming loose.i have it completely locked and it still slips! thanks for the tip btw

[discostu]

are you sure its not the bolt that holds it together un doing have you thread locked that part.

[09 lex 250]

i havent thread locked the bolt.only the nut.

[matdodd]

When you build the slipper clean all the thread lock off and wind the nut to its loosest setting then screw the centre screw all the way down with a little thread lock if you want. Then set the slipper nut to the desired setting once in the car! you shouldn't need thread lock on the slipper nut because then it makes it difficult to set!