Shaun Walsh Posted May 11 Share Posted May 11 I have inherited a model from a late club member and I'm trying to sort out a suitable battery and prop combination. The motor is 38mm diameter back plate to front of motor is 42mm shaft is 14mm long 5mm diameter. It's wired to an 80 amp skywing esc which appears to have a separate BEC piggy backed onto it. It came with a 10x6 prop and I believe it ran on a 4s battery. The model weighs 2 kg without battery. Quote Link to comment Share on other sites More sharing options...
Tom Gaskin 1 Posted May 11 Share Posted May 11 That looks like the sort of motor that I was buying from Giant Cod, many years ago! My examples are 800kv, and run nicely on 4s, with a 10x6, or 12x4. Tom 1 Quote Link to comment Share on other sites More sharing options...
Geoff S Posted May 11 Share Posted May 11 It's obviously not easy to weight the motor without removing it from the model but the usual rule of thumb is 3 watts/ gram of motor weight. You could roughly measure the kv by running it off load with a known battery voltage and measuring the rpm with an optical tacho (the white label may be enough to offer a once/rev indication). I'd agree with Tom in his guesstimate of its capabilities. With a 5mm shaft diameter it's likely to be happy with a 35/40 amp current draw (approx 500 watts?) Quote Link to comment Share on other sites More sharing options...
Shaun Walsh Posted May 11 Author Share Posted May 11 35 minutes ago, Geoff S said: It's obviously not easy to weight the motor without removing it from the model but the usual rule of thumb is 3 watts/ gram of motor weight. You could roughly measure the kv by running it off load with a known battery voltage and measuring the rpm with an optical tacho (the white label may be enough to offer a once/rev indication). I'd agree with Tom in his guesstimate of its capabilities. With a 5mm shaft diameter it's likely to be happy with a 35/40 amp current draw (approx 500 watts?) 500 watts should be plenty for flying at scale speed, the 80 amp esc is probably overkill on a 10x6 on 4s but he was known to reuse/recycle/repair so it was probably in the bits box. Think I will run it up and measure the current on the 10x6 with a 3s battery and swap it for a 12x6 and repeat. 2 Quote Link to comment Share on other sites More sharing options...
Frank Day Posted May 11 Share Posted May 11 Start as is and give it a good thrashing until you need to replace it with a known one. Quote Link to comment Share on other sites More sharing options...
Tom Gaskin 1 Posted May 12 Share Posted May 12 With sufficient cooling I can run my Giant Cod specials on 5S to get a brisker performance! Tom Quote Link to comment Share on other sites More sharing options...
Shaun Walsh Posted May 12 Author Share Posted May 12 I have run the motor up using a 3s battery and measured approx 440 watts on the 10x6 prop. However it was running a bit rough and investigation shows that the bearings have seen batter days. The allen screws on the motor look a bit dodgy so i will replace the motor. I think I will also replace the ESC as the separate BEC added on does not inspire confidence. Quote Link to comment Share on other sites More sharing options...
Shaun Walsh Posted May 13 Author Share Posted May 13 Digging into the archive shows that the model is pre 2011 so I think I will update all of the electrics, model itself is in good physical condition. 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.