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Electric Stunt => Gettin all AMP'ed up! => Topic started by: jfv on November 06, 2018, 10:36:30 AM

Title: Bearings for Cobra 2820
Post by: jfv on November 06, 2018, 10:36:30 AM
Want to replace the bearings on my Cobra 2820.  Wondering what would be better: OEM replacement or BOCA?  If BOCA, what specific type as there are several that fit.

THX
Title: Re: Bearings for Cobra 2820
Post by: Fred Underwood on November 06, 2018, 01:20:50 PM
Front or rear mount?  Rear mounts seem to use bearings, much more than front.  I have put about 1000 flights on Cobra bearings with a front mount motor.  Not close to that with rear.  Some of the rear mounted flyers gave up on Cobra.  It apparently has to do with harmonics of the spinning case, and even better bearings will fail.  It will be interesting to see other opinions.
Title: Re: Bearings for Cobra 2820
Post by: jfv on November 06, 2018, 04:45:33 PM
It's a front mount.  The motor has a ton of flights.  Just a little slop side to side and just thinking of doing some preventive maintenance.
Title: Re: Bearings for Cobra 2820
Post by: John Tate on November 06, 2018, 05:04:58 PM
I am happy with the bearings from http://rcbearings.com/ (http://rcbearings.com/). The quality is good and the cost is less than Boca Bearings. You just need to know what size that you need.
Title: Re: Bearings for Cobra 2820
Post by: Crist Rigotti on November 06, 2018, 11:26:24 PM
It's a front mount.  The motor has a ton of flights.  Just a little slop side to side and just thinking of doing some preventive maintenance.

Just use Cobra bearings.  The ones you have have a "ton of flights" on them.  The replacements should also provide a "ton of flights" too.
Title: Re: Bearings for Cobra 2820
Post by: Ken Culbertson on November 07, 2018, 08:11:23 AM
Just use Cobra bearings.  The ones you have have a "ton of flights" on them.  The replacements should also provide a "ton of flights" too.
How easy is it to change bearings?  I have 2 Cobra 2820's one of which got fried when the wrong wire touched another wrong wire.  Bearings should still be good though.  Mine will soon have a ton of flights on it too.

Ken
Title: Re: Bearings for Cobra 2820
Post by: jfv on November 07, 2018, 08:28:30 AM
Not very difficult to change bearings.  Here's a video from Inov8tive Design on how it's done.

https://www.youtube.com/watch?v=3RJQfbzXNjQ&list=PLMy5bnpkH-HyH5P8-atqqnYQEsFlmwR8j&index=13&t=271s

Also, you will need an arbor press.  I have one from Harbor Freight that works great.

https://www.harborfreight.com/1-ton-arbor-press-3552.html  Very reasonable when they are on sale.
Title: Re: Bearings for Cobra 2820
Post by: Ken Culbertson on November 07, 2018, 09:26:15 AM
Not very difficult to change bearings.  Here's a video from Inov8tive Design on how it's done.
Thanks - Harbor Freight is a regular stop, I will check it out.  I had to swap out the bearings in a couple of IC engines and it was not too difficult.  Glad the electrics are just as easy.  Is there anything else that can wear out?

Ken