Was curious....anyone else blowing up rotors on your 17.5.....I just blew up my second one in 6 mos...........I run it with the timing fully cranked and
the motor is usually 155 deg. when it comes off the track..(we run 5 min's races.......Anyone else going through this...........starting to get puzzled....

By blowing up I mean the rotor's sleeve comes undone.....

it will happen when the motor is allowed to free spin with no load...otherwise it's more of the great quality control you can expect from novak,lol....did i just say that? errrrrrrr

Bud why 155 degress that is a littel on the hot side .I ran one that hot and it melted the glue on it since then i don't let them get above 145 Try that

I've been told 130-135 and no more than that. The only free spin issues I have heard about were in the lower turn motors, not the 17.5's

155 is not that hot... My 17.5 after a 5 min race is in the 160-165 range.
I was told by novak that you could run those motors all day long at 180 deg with no problem.....:confused:

ditto..
Sorry Larry,just damn to much for gas this year to come down and run with you guy's on the "BIG" tracks..sucks..

Never free rev (any) brushless motor:

The act of free revving – running a brushless motor at high RPM under no or little load for an extended period of time – can cause damage and subsequent failure of a brushless motor and/or an ESC.

If allowed to accelerate too high, the rotor can break apart, causing an immediate halt in the rotation of a brushless motor. Not only will this damage the internals of a brushless motor, but in some instances, can damage the ESC as well. The likelihood of a rotor failure is significantly increased if a brushless motor is free revved while hot, such as after a full-battery pack run.

Because brushless motors can attain such high RPM under no – or low – load conditions, the centrifugal forces in the rotor can cause it to break apart.

We recommend that you never free rev your brushless motor in or out of your vehicle. Any damage sustained from free revving is not covered under Novak's product warranty.

http://www.teamnovak.com/tech_info/free_revving_warning/free_revving_warning.html

FWIW, this issue has nothing to do with QC.

see i was right! ahahahha

I understand the concept concerning free reving.....Hower I have been in the hobby for at least 10 years......I dont free rev the motor in the car......I race oval and race the car on the track...not sit in the pits free reving.....This is the second rotor that came apart on me racing 4 cell 17.5 in 6 months...Wondering if anyone is having this problem...........

also......My rotors coming apart looks like the epoxy came undone and the sleeve
slid right off.....Not total destruction like the picure posted on the web site.....The car
feels like the diff just got loose and then stops....

Bud, I had the same problem. I didn't free rev either. It looks like the glue just didn't set good, and it came loose.

thats what i wanted to know....is the glue coming undone because of heat..?......can it be reglued?......what is Novaks max oper temp for these things?...i thought i read on the paperwork when i bought it 160.....

I've had my 10.5 come off the track at over 200 degrees more than once. Also some of my best runs were at that temp. The track record holders motor frequently runs that hot. My rotor has not gone down on the zubak meter at all.

Did the magnets come off the rotor in the first few runs or over a longer period of racing?

I'll ask Adnan and Charlie if they have any info, and post it here.

If it's a free reving issue, the broken magnet should resemble the one pictured on the web page.

Mine did NOT come apart. The magnet came loose from the rotor shaft. It might have had 5 runs on the motor. It never got any hotter than 170 before the magnet came off. Like Bud said, it sounded like a very loose diff. It would rev up but not pull. I pulled the motor apart, checked the rotor, and thats what I found.

Email charlie@teamnovak.com

He can send you a new rotor. When the motor/rotor is under warranty, we replace it.

Is your rotor the standard Velociti rotor?

Mine did NOT come apart. The magnet came loose from the rotor shaft. It might have had 5 runs on the motor. It never got any hotter than 170 before the magnet came off. Like Bud said, it sounded like a very loose diff. It would rev up but not pull. I pulled the motor apart, checked the rotor, and thats what I found.

see i was right! QC baby!

I'll send him an email.....Im curios why the unit keep coming off.....second rotor to do this in 6 months.................

also......My rotors coming apart looks like the epoxy came undone and the sleeve
slid right off.....Not total destruction like the picure posted on the web site.....The car
feels like the diff just got loose and then stops....

can you post a pic of what yours looks like i would like to see it, i usually tear my motor down once a week and inspect the rotor and oil the bearings and checking the rotor to see if it is starting to do what yours has done twice could really help some one save them self from really messing up a motor...

you will not beable to see anything broken..but if you hold the shaft the pinnion goes onto with pliers and another set of pliers on the magnet you will be able to twist them around...the shaft rotates inside the magnet..thats not supposed to happen ....free reving will results in easy to see damage.

thanks kat sucks you had to miss the fcc race today i wasn't there either.. one thing can be said about b/l racing is that its getting closer and closer every week good job novak

thanks kat sucks you had to miss the fcc race today i wasn't there either.. one thing can be said about b/l racing is that its getting closer and closer every week good job novak


Wonderful!! something else to worry about on the Novak BL motors!! I have 4 motors and I better take them apart and check for loose glue on the rotors.

dont bother checking...nothing you can do about it....youll know if it happen...car has
no hard acceleration....like a loose diff

IT REALLY SUCKS THAT EVERY BODY HAMMERS NOVAK ON THESE BOARDS ALL THE TIME THE ONLY REASON WHY WE HAVE SO MANY PROBLEMS WITH THEM IS BECAUSE THATSE S ALL ANY ONE IS ALLOWED TO USE IF EVERY ONE HAD TO USE LRP BRUSHLESS MOTORS THEN EVERY ONE WOULD BE ON HERE BAD MOUTHING THEM. YOU HERE A LOT OF HORROR STORIES ABOUT NOVAK STUFF BECAUSE THE MAJORITY OF THE STUFF BEING RAN IS THERES. ONE THING THAT CAN BE SAID ABOUT THEM IS THAT THE CUSTOMER SERVICE IS SECOND TO NONE TRY GETTING SOMETHING WARRANTIED BY ANOTHER COMPANY AND SEE WHERE YOU GET. I LOVE MY NOVAK STUFF AND THATS all i plan on running

i agree 100% Novak atleast trys to fix problems when it comes up. thanks a ton!

IT REALLY SUCKS THAT EVERY BODY HAMMERS NOVAK ON THESE BOARDS ALL THE TIME THE ONLY REASON WHY WE HAVE SO MANY PROBLEMS WITH THEM IS BECAUSE THATSE S ALL ANY ONE IS ALLOWED TO USE IF EVERY ONE HAD TO USE LRP BRUSHLESS MOTORS THEN EVERY ONE WOULD BE ON HERE BAD MOUTHING THEM. YOU HERE A LOT OF HORROR STORIES ABOUT NOVAK STUFF BECAUSE THE MAJORITY OF THE STUFF BEING RAN IS THERES. ONE THING THAT CAN BE SAID ABOUT THEM IS THAT THE CUSTOMER SERVICE IS SECOND TO NONE TRY GETTING SOMETHING WARRANTIED BY ANOTHER COMPANY AND SEE WHERE YOU GET. I LOVE MY NOVAK STUFF AND THATS all i plan on running

This thread was not a Novak Bashing thread....Your right...Thier customer service is second to none...Was curious if anyone could solve this problem so it doesnt keep happening..............

Novak may have to start using Gorilla Glue!!! http://www.hobbytalk.com/bbs1/images/icons/icon10.gif