Motor KV?

[M.M.]

If i purchased a hacker b50 8l for this boat:

http://cgi.ebay.com/25-deep-vee-ARTR-with-motor-and-ESC-racing-spec-white_W0QQitemZ290323053764QQcmdZViewItemQQptZRadio_Control_Vehicles?hash=item43989a3cc4&_trksid=p4634.c0.m14.l1262&_trkparms=%7C301%3A0%7C293%3A1%7C294%3A30

Can i run it on 2s and 3s? With a turnigy 120A ESC

[Diegoboy]

Yes.

[M.M.]

Thanks.

What about one of these motors?

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=6678

[Diegoboy]

That motor kV is too low for 2S or 3S

[M.M.]

What would be better for KV? because i have two 3s 2200 25c lipos that i run in parellel, and i have 2 2s 5000 20c lipos that i can run in series or parrellel. So what is better high or low KV? I would prefer to run the 2s in parellel to get 10000mah. Then ill have the 3s in parellel for just messing around.

So around what is a good KV for 2 and 3s?

[TRUCKPULL]

The 2880 kv motor it comes with would be OK (about max RPM for a mono) on 3S.
I would not run it on 4S.

It would also be OK as a Sport boat on 2S

Larry

[ozzie-crawl]

with your 2s 5000 in series run either a ammo 2300 x440 prop see you around 45mph. if more speed is wanted try a 8xl x640 prop

[M.M.]

So it would be better to run a lower Kv motor with higher voltage, rather than lowering the voltage with a higher Kv motor?

[domwilson]

This thread has a lot of good info. http://forums.offshoreelectrics.com/...read.php?t=271

[ozzie-crawl]

generally yes. i have seen a lot off people try and run these on high kv 380 or cheap 540s motors and usally all they do is pull high amps
i look at it this way the bigger xl motors can pull more amps but they have more power so they can spin the same size prop a lot easier so they dont pull more amps. my 25" mono runs a ammo 2300 on 4s with a x440 and i only run a 45amp esc. the esc and batteries you have should be enough for a 8xl
i would start with a x440 and go from there

[domwilson]

Agreed. Someone once told me, a "S" motor should be considered like a 4 cyl. An "L" like a 6 cyl. and a "XL" like a 8 cyl. At least as far as the chinese 2 pole motors go. Take a look at post #19 in my previous post for general guidelines.

[ozzie-crawl]

i like that analogy now with the 580l we also have the supercharged v8

[M.M.]

[quote]with your 2s 5000 in series run either a ammo 2300 x440 prop see you around 45mph. if more speed is wanted try a 8xl x640 prop [quote]


Well i got an 8xl coming my way, now what can i do for the prop situation? Because i beleive it is an 1/8 shaft. Can i just use a little shim? That way i can run the 3/16 x640

[domwilson]

[QUOTE=M.M.;102968][quote]with your 2s 5000 in series run either a ammo 2300 x440 prop see you around 45mph. if more speed is wanted try a 8xl x640 prop

Well i got an 8xl coming my way, now what can i do for the prop situation? Because i beleive it is an 1/8 shaft. Can i just use a little shim? That way i can run the 3/16 x640

Yes. You can put a small piece of k&s tubing in the prop to shim it up http://www.offshoreelectrics.com/inf...propellers.php

[M.M.]

Ok, thanks

Now i need ozzie crawl to check out this thread and make sure an x640 is the right prop?