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JK Hawk Retro vs JK Hawk 7

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#26 Matt Sheldon

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Posted 20 June 2019 - 12:02 PM

I am assuming that your break-in method posted is for the Retro Hawk? A Hawk 7 will not have much brush left after 10 seconds in Simple Green.

I personally have not seen a Retro Hawk come back or have average performance when it is under .40 amps. A dud is a dud!
Matt Sheldon

#27 Ron Sullo

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Posted 20 June 2019 - 02:12 PM



Used that break-in method on a half dozen Retro Hawks this week and 5 motors came in at .51 - .54 / but number 6 came in at .41 and thought this was the sweet one / had to double check / someone at my race track told me that the lower amp pulls on the RH are the silver bullets /


thanks for the honest advice

very much appreciated

Ron Sullo
"... the future is uncertain and the end is always near - let it roll, baby, roll..." 

#28 dalek


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Posted 21 June 2019 - 07:54 AM

There was a time that HR and H7 brushes were soft but my observations of the recent batches are that the brushes in both motors are relatively hard.


The packages say 10-15 minutes at 5 volts for break in but after 15 minutes I can't see any difference looking at the comm.  What I mean is that the two thin dark lines on the comm don't look like they're any wider than they were when the motor came out of the package so I just put the new motor in a car and put it on the track.  The motors are often fast by the time I've run 50 laps even though the brushes are not yet fully seated.


The above method has been working very well for me.  I say this because my cars often TQ.



#29 Phil Beukema

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Posted 21 June 2019 - 12:03 PM

The brushes seem harder to me as well.


I just microwave a cup of water to the point I can just hold my finger in for only a couple of seconds.

I run the motor in the hot water on 4 volts for 2 min intervals until the carbon streaks evenly across the comm indicating the brushes are fully seated.

Spray it out with electrical parts cleaner and oil it.


Seems to work fine.

"Line 'em up!"

#30 Tim Wood

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Posted 13 July 2019 - 10:43 AM

So you don't use the Hawk 7, on the King, in any class?

Yes we have in the past until Pheonix motors came out. LMP Flexi on King with Hawk 7. I set our track record with a Hawk 7 Redfox Acura body LMP on King track. We race every third week on king track now with the Pheonix motors, we are thinking of trying to race 2 classes, Pheonix and Hawk 7. All rest of month we race Flat track Hawk 7 LMP. My main question though was for the Associations across the country for Scratch Built CanAm & F1 races why not use Hawk 7 motors instead of Hawk Retro or if you have an option as Race Director with hand-out motor races why not try the Hawk 7. I hope to in the near future be able to visit some Tracks and race with these groups. Thanks,


 Tim Wood

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#31 gc4895


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Posted 13 July 2019 - 09:46 PM

For F1 (and stock cars) we use the JK MB or old Slick 7 mini brute. The Hawk 7 is, simply put, too fast. Our program manager has quite correctly divined that higher rpm motors do not translate into more competitive or fun competitions. In fact, our mantra is figuring out how to go faster by chassis and set up innovation rather than applying brute horsepower or , in my view, the real killer of competitive racing, employing the high downforce body.

Stronger motors always favor those talented users of wire chokes.
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Mark Bauer

#32 Fast Freddie

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Posted 14 July 2019 - 11:16 AM

Just so your aware.  When you use the Simple Green method of seating the brushes make sure you check the comm. slots for excessive brush material.  Even if you use a water clean and motor flush after, brush material may still remain in the slots.  I burnt up a motor and  damaged another before I caught on to what was happening.  I use a toothpick to clean the slots, tedious but necessary.  I also recommend letting the motor sit for at least 30 min before running on the break in box, just as a precaution.  I run the motor in Simple Green until the brushes are seated, some take longer than others.  Then a short, 5 sec., dunk in clean water, then air dry, then motor flush, then air dry, finally check and clean out the comm. slots.

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