Motor choice help please

[jrod155]

I'm stepping up and finally getting a 7hv. I'm trying to decide on which motor to get.

I'm in between the new compass motor and a 700mx 510. I think I'm going to want to fly around the 1800-1900 head speed area, I want at least 5 min flights. I've seen videos of the 700mx and have been impressed and they're cheap in the classifieds, but after owning a 6hv, I know how good compass motors are.

Thoughts?

[belcom]

Compass motor all the way. The wait is almost over.

[myrseth]

The new kit motor is awsome ;)

[buzzsaw 46]

We'll have to see the price on the Compass motor but the 700MX is a viable option. I would rather have the Compass motor but if it's more than double the price I will have to keep my MX for a while.

[eightythree]

I had first flights last weekend on my 7hv. 700mx 510kv 14t pinion. I was playing around with headspeed numbers that you want to run, good power and cool motor. Running 4:30 flights (smooth 3D, not much banging) times coming down at storage levels on 5amp packs.

A little more tuning and i think its a good motor choice. I may have to go down to a 13t pinion to use 1800-1900 more effeciently. Ice120 was a bit warm after running 1800-1850.

This heli flies so smooth at lower headspeeds. It does suffer a bit on collective at lower speeds, but one could run 4amp packs to ease up on weight, run1800 and still get 4:30-5min flights

[eightythree]

http://m.youtube.com/?reload=7&rdm=m1n4ps2me#/watch?desktop_uri=%2Fwatch%3Fv%3D5-C-cXvgNFM%26feature%3Dyoutu.be&feature=youtu.be&v=5-C-cXvgNFM&gl=US

flight #4 beginning of the flight is 1950 12degrees pitch, performs really well. Dropped to idle 1 at 1850 around :50 in the video. The 700mx is enough for my flying style :thumbup:

next flights i will be trying 1550 normal, 1800, 1900. Going to keep at eye on esc temps so i dont get the magic castle smoke.

[G200driver]

http://www.xeramotors.com/index.php?page=shop.product_details&flypage=flypage-ask.tpl&product_id=32&category_id=1&option=com_virtuemart&Itemid=1

This motor deserve a look as well.. Power is unboggable at 13/13 pitch with my HeliJive 120..And I do mean BIG power, comes own cool..

[Rob43]

I have flown my 700MX-510 a lot. It is a decent motor. It's no powerhouse though, and I feel that for the 7HV, it's just not going to do much more than about 1950-2000 rpm without some issues. I am not expert enough to know the details well, but I believe the ESC would be seeing some stress above that RPM trying to push more through the motor than the motor will handle. Others may tell me I am all wet, but trying a bunch of headspeeds, it just seems that gearing it to perform within the ESC's best range (say, governed no more than 75-80% throttle) will produce the best overall results. And whatever headspeed that turns out to be - so be it. I found the 14t to be my best pinion for this motor. Honestly, I prefer how it all works with a bit less head speed for the 700MX. Set up with 13 pitch, about 1750 rpm, and it will do anything you want without feeling sluggish. At least that has been my experience. And, at that speed - you can fly 6 min flights all day long. :YeaBaby:


Best wishes,

[Stolla]

Really not a difficult decision, if you dont fly really hard 3d or high speed the mx motor is the right choice, cheap,stays cool and decent power. If you want all out power and speed go for the scorpion le motors (runs hot) or wait for the new cpass motor. Alternatively if you want to spend a little more for power inbetween pyro 700-52. mx is a copy of pyro but conservative winding. there is no better cooling concept than the pyro. 99 percent of pilots have motors that are overkill, they want the most powerful motors but dont come close to using the potential of these motors then a motor like mx makes more sense, longer flight times etc.

[jrod155]

Thanks for the help guys, I'm hoping to order this week or next.

[Rob43]

Make sure to check the classifieds. Many guys buy 700e and immediately go for the big guns. Save some coin. I have a Scorpion 4035 long shaft for mine which I will install some day. It's easier to do maintenance with the Scorpion shaft, and permits setting the axial clearance of the can to stator very precisely.

[eightythree]

Really not a difficult decision, if you dont fly really hard 3d or high speed the mx motor is the right choice, cheap,stays cool and decent power. If you want all out power and speed go for the scorpion le motors (runs hot) or wait for the new cpass motor. Alternatively if you want to spend a little more for power inbetween pyro 700-52. mx is a copy of pyro but conservative winding. there is no better cooling concept than the pyro. 99 percent of pilots have motors that are overkill, they want the most powerful motors but dont come close to using the potential of these motors then a motor like mx makes more sense, longer flight times etc.

This is exactly the same reasons I went with an MX motor. Plus I picked it up for a pretty good price NEW here on the forums. All in all I was going for more of a nitro power band feel and it does just that.

[levpardede]

how about 700mx 530kv is good? is stock 13T pinion do the job for governor (2100rpm) or 14T pinion, thanks..

[OverTemp]

My Pyro rocks and is very very light. I didn't appreciate the cooling of it until I ran it up on the bench... Air is blowing out of that thing like a hair dryer.

[GimpyGolden]

OverTemp, you are running 12tooth pinion correct?

[OverTemp]

Stock 13T w/ the 700-52. Gets up in the rpm range further than I want to fly on a daily basis... I usually have the curve cranked back to the low 70% range and the thing is fun... About 1950.

[GimpyGolden]

Ah good then.
I have a 12 tooth to try on V-Bar Gov with a max head speed of 1900 but I am worried about the lesser contact pattern over the 13+ tooth gears.

I will be using 4000 mAh packs(when they arrive) so anticipate a slightly lower head speed will do the same job with less weight.

[OverTemp]

Still haven't fown with the 4K's, huh?

I've got 3 sets of them... haven't tried yet though.

[Gawl]

I ran 4k's on mine a couple times, think I was at 1800-1900 headspeed and got 4 mins on em.

[GimpyGolden]

Hmm 4min is not good, hoped for 5 at least.
Guess I'll see when I have them, should be a week or two.

[Gawl]

I'm guessing at the head speed though. When I ran the 4k packs I had my atv's adjusted and apparently you shouldn't do that with the jive. I had my timer set for 5 mins and ran them the full five and when they came down I was 3.69-3.72 per cell. So you could probably run 4:30 depending on how hard you fly, mine was just sport flying.

I have adjusted my atvs back to normal 100/100 and just by tone my head speed was louder. I finally got the app for my phone and tached it at 2200. So not completely sure what my speed was with the adjusted atv's but it was lower for sure.

Once I get my bird back in the air in the next day or 2 I'll let you know what I'm getting. The 4k's I used were the Gens Ace 25c ones.

[OverTemp]

I ran 4k's on mine a couple times, think I was at 1800-1900 headspeed and got 4 mins on em.

That's good to know. Even with the 4k its a large heavy Heli... Nothing is free.

I'll prolly stick with bigger packs. Anyone want a decent deal on never-charged TP 65C 6S 3850s? Wanna go lighter in the logo.