KB45 VS. LEHNER 2250 VS. LEHNER 1950
12-08-2009, 05:51 AM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
I've read people removing one shim as a mod. It seems the shims make the rotor fit too tight and it stresses the bearings.
My friend got his KB45L 1800KV and we tested it yesterday. Free run for short period of time. What was surprising to us is how well balanced the rotor is, but on the other hand the front end of the motor was heating up much faster than the can itself. This seems to be problem with the too tight shims inside we think.
Does anyone know how to disassemble the KB45 in a humane way?! I can see glue on the outside so no question there, but are the ends threaded and glued or just press fitted and glued?
My friend got his KB45L 1800KV and we tested it yesterday. Free run for short period of time. What was surprising to us is how well balanced the rotor is, but on the other hand the front end of the motor was heating up much faster than the can itself. This seems to be problem with the too tight shims inside we think.
Does anyone know how to disassemble the KB45 in a humane way?! I can see glue on the outside so no question there, but are the ends threaded and glued or just press fitted and glued?
12-08-2009, 04:34 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
I believe the only way to pop one of is to hit the shaft gentle on a flat surface for a couple of time until it pops off. These is surely more, less risky ways to do it but thats all ive heard.
Also i might end up buying two kb45l because of the 1800kv rating which is right on the dot of rpms i was looking for.
Also i might end up buying two kb45l because of the 1800kv rating which is right on the dot of rpms i was looking for.
12-08-2009, 10:01 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
ORIGINAL: gonggongboy
I believe the only way to pop one of is to hit the shaft gentle on a flat surface for a couple of time until it pops off. These is surely more, less risky ways to do it but thats all ive heard.
Also i might end up buying two kb45l because of the 1800kv rating which is right on the dot of rpms i was looking for.
I believe the only way to pop one of is to hit the shaft gentle on a flat surface for a couple of time until it pops off. These is surely more, less risky ways to do it but thats all ive heard.
Also i might end up buying two kb45l because of the 1800kv rating which is right on the dot of rpms i was looking for.
NOOOOOO!
The front cover unscrews easily. Just install mounting screws and twist counter clockwise. Easy Peasy...
12-09-2009, 04:52 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
ORIGINAL: norbique
Thanks BACKEMF!
So it unscrews, but what's with the transparent glue I can see where the front and the can meets?
Thanks BACKEMF!
So it unscrews, but what's with the transparent glue I can see where the front and the can meets?
12-09-2009, 07:33 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
Jeeeez. My bad i thought they were like most brushless motors never knew they were threaded. Sorry about that.
01-02-2010, 08:00 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
I made the similar mistake when I bought a RTR that came with the cheapo 3900 kv motor (bigger kv number almost always impress the newbies!).
This very motor caused me several ESC even though they rate 150 A and up. I am also thinking about getting a KB45 just for testing but afraid to fry another ESC, so here I am after searching this wonderful and informative forum and may have saved me $$$ already.
Thanks to all the contributors.
This very motor caused me several ESC even though they rate 150 A and up. I am also thinking about getting a KB45 just for testing but afraid to fry another ESC, so here I am after searching this wonderful and informative forum and may have saved me $$$ already.
Thanks to all the contributors.
01-03-2010, 04:45 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
the clear stuff is resin, they soak the wires in it aswell for a protective coat, they can be run under water (with waterproof bearings) i did the same mod, removed one shim from the rear and put in another nylon thrust washer so no metal grinding, i was thinking of putting some high temp lithium grease on the inside of the bearings, only a small amount, but dont know if it would ignite with the heat, removing the one shim has brought the temp's down by almost half over a 1 minute runtime
DO NOT remove anything other than the shim, the blue stuff on the magnet rotor is for balance like they do on wheel rims and the rest is all protective coating
DO NOT remove anything other than the shim, the blue stuff on the magnet rotor is for balance like they do on wheel rims and the rest is all protective coating
01-05-2010, 01:17 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
ORIGINAL: gonggongboy
I saw a forum on Offshorelectrics, were a guy rebuilt his kb45. His problem was that the shims in the motor were to tight causing play and poor effeincy. And simply as by buying new shims of different size he increased the effiency alot more than it was. Now he has no problem with keeping it cool and its has little at all play.
I saw a forum on Offshorelectrics, were a guy rebuilt his kb45. His problem was that the shims in the motor were to tight causing play and poor effeincy. And simply as by buying new shims of different size he increased the effiency alot more than it was. Now he has no problem with keeping it cool and its has little at all play.
01-05-2010, 01:20 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
it is till you remove one shim from the rear endand put in a nylon washer, i have about 2mm-3mm play now like i have in all my motors, this was the first one i modifyed, but its running cooler now with the shim gone
01-06-2010, 02:37 AM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
they have 3 shims in the back, thats why there so tight, its easy to knock the back end cap of and take one out
01-06-2010, 02:41 PM
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RE: KB45 VS. LEHNER 2250 VS. LEHNER 1950
ORIGINAL: nick 30
yeah, your correct, the back is press fitted, thats why i put thread locker front and back
yeah, your correct, the back is press fitted, thats why i put thread locker front and back
