Blade CP - uncommanded rpm changes
#1
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I've recently experienced a new problem with my Blade CP...
Sometimes the main rotor rpm will increase or decrease without any throttle stick change.
I first noticed this problem while in forward flight when it just seemed to drop coming out of a turn.
Then I noticed the uncommanded rpm changes while just hovering.
I've flown the chopper quite a bit and have been doing forward flight for about a dozen outings.
Anyone else experience this?
Any ideas?
Thanks!
Chuck
Sometimes the main rotor rpm will increase or decrease without any throttle stick change.
I first noticed this problem while in forward flight when it just seemed to drop coming out of a turn.
Then I noticed the uncommanded rpm changes while just hovering.
I've flown the chopper quite a bit and have been doing forward flight for about a dozen outings.
Anyone else experience this?
Any ideas?
Thanks!
Chuck
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have you tried flying with the idle up? does it improve things?
I find sometimes the RPM's drop when sending power to the tail.
I find sometimes the RPM's drop when sending power to the tail.
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i was going to say it's normal for the heli to drop coming out of turns, especially if you slow down during the turn. however, you said it changes rpm while hovering, which is not normal unless there's a fair amount of wind & you are commanding the throttle change to hold altitude.
if i had that problem i'd start looking at head slop. if the pitch is jumping around on you, the changing torque could appear to be a throttle change. the usual culprits for that are: bent spindle shaft, loose/binding links, loose/binding hiller arms, separating swashplate, & loose shaft collar.
hope this helps,
-kev
if i had that problem i'd start looking at head slop. if the pitch is jumping around on you, the changing torque could appear to be a throttle change. the usual culprits for that are: bent spindle shaft, loose/binding links, loose/binding hiller arms, separating swashplate, & loose shaft collar.
hope this helps,
-kev
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Also one other thing... if you say you have quite a bit of flight time, have you ever changed the main motor? They only last up to about 20 flight hours, or about 60 to 80 flights on the conservative side. you might try replacing it and see if your problem goes away
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ORIGINAL: mrasmm
Also one other thing... if you say you have quite a bit of flight time, have you ever changed the main motor? They only last up to about 20 flight hours, or about 60 to 80 flights on the conservative side. you might try replacing it and see if your problem goes away
Also one other thing... if you say you have quite a bit of flight time, have you ever changed the main motor? They only last up to about 20 flight hours, or about 60 to 80 flights on the conservative side. you might try replacing it and see if your problem goes away
I was having the same problem, the guy at HeliHobby told me that main motors will last about a year or so...

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Flying with the idle up doesn't seem to help much.
ORIGINAL: vortex05
have you tried flying with the idle up? does it improve things?
I find sometimes the RPM's drop when sending power to the tail.
have you tried flying with the idle up? does it improve things?
I find sometimes the RPM's drop when sending power to the tail.
#7
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I don't think it's a pitch problem because the heli climbs when the RPMs increase, and then descends when the RPMs drop again.
ORIGINAL: Truglodite
i was going to say it's normal for the heli to drop coming out of turns, especially if you slow down during the turn. however, you said it changes rpm while hovering, which is not normal unless there's a fair amount of wind & you are commanding the throttle change to hold altitude.
if i had that problem i'd start looking at head slop. if the pitch is jumping around on you, the changing torque could appear to be a throttle change. the usual culprits for that are: bent spindle shaft, loose/binding links, loose/binding hiller arms, separating swashplate, & loose shaft collar.
hope this helps,
-kev
i was going to say it's normal for the heli to drop coming out of turns, especially if you slow down during the turn. however, you said it changes rpm while hovering, which is not normal unless there's a fair amount of wind & you are commanding the throttle change to hold altitude.
if i had that problem i'd start looking at head slop. if the pitch is jumping around on you, the changing torque could appear to be a throttle change. the usual culprits for that are: bent spindle shaft, loose/binding links, loose/binding hiller arms, separating swashplate, & loose shaft collar.
hope this helps,
-kev
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I'll try changing the motor. Still running the motor that came with it. I have the 9 tooth motor that came with the aerobatic kit, so now would be as good a time as any to upgrade to the symmetrical blades and a 3-cell LiPo.
Should I go ahead and replace the tail motor at the same time? I'm still using the original tail motor.
Should I go ahead and replace the tail motor at the same time? I'm still using the original tail motor.
ORIGINAL: mrasmm
Also one other thing... if you say you have quite a bit of flight time, have you ever changed the main motor? They only last up to about 20 flight hours, or about 60 to 80 flights on the conservative side. you might try replacing it and see if your problem goes away
Also one other thing... if you say you have quite a bit of flight time, have you ever changed the main motor? They only last up to about 20 flight hours, or about 60 to 80 flights on the conservative side. you might try replacing it and see if your problem goes away
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how many battery packs do you think you've put through it?
I have a meter on my heli that jumps down to red just before a motor is failing. That is a great safegard for me, because I have had 2 motors now that blinked red on my meter, so I brought it in for a low close hover, and both within about 5 min bit the dust and sent the heli piroing. No damage done though so close to the ground. Just ease back on the throttle and set'er down easy.
I agree with trug, a spare is always a nice thing to have. you may want to break them in first too. I have a guide that is in the forum just above this one as a sticky.
hehe yeah, they may very well last a year if you only put 1.5 or 2 flights on it per week =) It's better to go off packs or flight hours instead of months days or years just because how much people fly their heli has a real big range on it.
I have a meter on my heli that jumps down to red just before a motor is failing. That is a great safegard for me, because I have had 2 motors now that blinked red on my meter, so I brought it in for a low close hover, and both within about 5 min bit the dust and sent the heli piroing. No damage done though so close to the ground. Just ease back on the throttle and set'er down easy.
I agree with trug, a spare is always a nice thing to have. you may want to break them in first too. I have a guide that is in the forum just above this one as a sticky.
ORIGINAL: LostByChoice
I was having the same problem, the guy at HeliHobby told me that main motors will last about a year or so...
I was having the same problem, the guy at HeliHobby told me that main motors will last about a year or so...
