K110 Low head speed

[LiquidDrift]

I'm trying to get my old beater up to the same power as my new BNF.

At first I thought it was just a friction problem, so I replaced the main shaft bearing (bottom one) and lubed it all up. The rotor seems to spin very freely now and the spool-down is much longer and smoother than the BNF, so I don't think that's the issue.

I swapped motors thinking that maybe the motor is old or the bearings on it need to be replaced, but the new motor performs about the same as the old one.

Today I took a close look at the losi connector and the ESC solder joints and everything looks OK, at least through the plastic.

The main shaft was replaced recently and the tracking looks fine so I don't think it's the feathering shaft.

Any other ideas?

[salrica]

https://www.rcgroups.com/forums/show...&postcount=393

[LiquidDrift]

Cool, I don't think it's the ESC because in that case I would expect longer flight times because it's using less energy to maintain the lower head speed, but it actually has shorter flight times vs. the new one. There's energy loss somewhere, gotta figure out where.

[JWeber]

All that's left seems like some type of electronics issue. I assume that you're using the same radio profile and batteries on both models.

You've checked for binding and even replaced the motor. All that's left are the RX board and ESC.

I'd try the calibration, just in case, but you may be left with a tired board. I'd just get a new model and use the old one for parts instead of ordering a new board. That is, if you want a second flying model or this low head speed bothers you enough.

[learnedthehardway]

Originally Posted by LiquidDrift

Cool, I don't think it's the ESC because in that case I would expect longer flight times because it's using less energy to maintain the lower head speed, but it actually has shorter flight times vs. the new one. There's energy loss somewhere, gotta figure out where.

If the esc is faulty it's certainly not going to behave as expected, just the opposite.

Are you using the same battery on both helis? Battery, motor, esc or throttle calibration/settings in tx are all it could be.

If the battery, motor and wires check out all that's left is the esc, rx and the tx. Have to check and eliminate those one by one.

Since you have one that works you can test the esc ect. in the bad one to find what cures it

[salrica]

My experience is that it's the ESC.
I bought an spare one as one was not giving me the same head speed as the others, when I installed the new one and did the calibration, it gave me the same speed as the others.

But you can try and swap ESCs

[LiquidDrift]

Yeah, using the same batteries and tx. I replaced the rx board about a week ago so that's not it. Just replaced the tail motor today thinking it's old and sapping power, but nope same head speed. OK, gotta be the ESC, thanks so much for the feedback guys! It is also possible that it's always been slow and I've just happened to notice it against the new BNF because I haven't had anything to compare it to. Or maybe it always just needed calibration.

Question - what do you replace the plastic covering on the ESC with when you cut it open for calibration?

Thanks again!

[salrica]

Personally with nothing, naked goes.
Landing gear push it up and keeps it in place.
Runs hot anyway, mines at least, naked helps

[LiquidDrift]

Is that OK with wet grass and mud though? My heli has seen a LOT of that here in the pacific nw. I think we had 3-4 months this year where we didn't have 2 consecutive days without rain. Set some records, not a great time for me to learn how to fly, lol.

[salrica]

http://www.ebay.com/itm/Heat-Shrink-...wAAOSwdzVXuuaC

Mine been in the rain and no problems, but for peace of mind, better get this

[LiquidDrift]

Originally Posted by salrica

http://www.ebay.com/itm/Heat-Shrink-...wAAOSwdzVXuuaC

Mine been in the rain and no problems, but for peace of mind, better get this

Cool, thanks for that link!

Alright, so I did the ESC calibration (very interesting process), but no dice on performance. Then I reprogrammed the motor timing to 'high' and did see a small jump in power and the batteries lasted a bit longer, so that was nice. It's still not quite at the power of my other heli, so I'm going to try replacing the upper main shaft bearing today and then probably order a new ESC.

Was thinking about picking up a couple of these batteries with the new ESC - has anyone tried these?

https://www.banggood.com/Gaoneng-GNB...p-1135270.html

[LiquidDrift]

Got a new ESC today, popped it on and BAM, back up to 5900-6000 RPM. Beater flying like new.

[soupy01833]

my k110 will not increase HS when I hit idle up. My BNF model does with no issues. When I flip the switch the HS stays the same even though I have a linear TC of 100.

Do you think this is just esc calibration? or do you think the ESC is shot? it seems to have always been this way. I am thinking the throttle just never finds 100 and seems to settle on 60 or so.

BTW both models are on the same transmitter

[salrica]

I would do the ESC calibration, throttle curve 0-25-50-75-100.
After the calibration you can have whatever percentage fits you.

Forgot, do you have same motor on both helis?
Has nothing to do with the calibration, just asking.
Take a look at motor wires if they look the same, old version has heat shrink covering all 3 wires, new motor not, all 3 separate

[soupy01833]

Ok I will do the calibration. And yes they both have heat shrink on all 3 wires. The bnf is what I was hoping for the rtf one just needs more HS


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[soupy01833]

The calibration resolved it. Thanks everyone.

This is indeed a valuable thread

[soupy01833]

spoke too soon. I have idle up now but the HS does not compare to the BNF one. I am ok with it for now. It still flies great.