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Old 16-01-2009
Chesty Chesty is offline
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Default No steering under heavy braking???

Hi

Gave the B-Max a quick pre-race blast up & down the hallway.

Noticed something that's never happened before, under full braking the steering wouldn't function for a couple of seconds, was as if the servo was starved of power?

I'm running Novak GTB combo, Sanwa 431 rx, HiTec 5925 digital servo & NiMH batteries.

I've ruled out the TX because it doesn't do it with my 2wd, I'm wondering if the speedo's power capacitor isn't charging or not charged enough to power the servo at that point?

Anyone got any ideas or experienced the same, any help would be much appreciated
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Old 16-01-2009
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sosidge sosidge is offline
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I haven't experienced it but it does sound like a lack of servo power as you mentioned.

Personally I would try swapping out the servo to something more reliable (I've had nothing but bad experiences with Hitec servos). Also, a high-torque digital servo like that is going to be quite heavy on power anyway.

The Novak speedos tend to give quite a good power output to the servos, so if swapping the servos doesn't work, you might have to run a receiver pack, or try swapping the ESC just in case it is faulty.
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Old 16-01-2009
Chesty Chesty is offline
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Cheers, I'll give it a try.

Thinking about it, the HiTec servo always has taken a second or two to start working when initially switched on. There could be a link...

I always thought this was just a quirk of the servo. My Futaba and KO's I've had in the past never did this though.

Serve me right for being a cheapskate
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Old 16-01-2009
ianjoyner ianjoyner is offline
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I've had a Hitec servo reset, it only happened when I was using an ESC with a weak BEC and had weak batteries. I've never had it happen with a GTB.

Are your NiMHs okay?
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Old 16-01-2009
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its because you are breaking 2 much, the wheels are lockin up and the car carrys on forward. back off the break abit an let the wheels do wot they are meant to. if that doesnt work stick a one way in it and make it like a 2wd under breaking. had the same problem wit my new s44. car diving into the corner under breaking an didnt turn in when i tried, stuck the one way in an its working amazin now
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Old 16-01-2009
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Quote:
Originally Posted by Chesty View Post
Hi

Gave the B-Max a quick pre-race blast up & down the hallway.

Noticed something that's never happened before, under full braking the steering wouldn't function for a couple of seconds, was as if the servo was starved of power?

I'm running Novak GTB combo, Sanwa 431 rx, HiTec 5925 digital servo & NiMH batteries.

I've ruled out the TX because it doesn't do it with my 2wd, I'm wondering if the speedo's power capacitor isn't charging or not charged enough to power the servo at that point?

Anyone got any ideas or experienced the same, any help would be much appreciated
Firstly, the power cap is there to help the fets in the esc drive better.....

If you are getting no steering throw, I would first look at the servo saver before anything else.
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Old 16-01-2009
Chesty Chesty is offline
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I'm pretty sure it's not a buggy/handling issue.

When I try to steer just after letting off the brakes there's nothing at the servo, doesn't even attempt to move - as if the servo has been switched off for a few seconds.

Guess the process of elimination by changing components will sort it...
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Old 16-01-2009
Bradders Bradders is offline
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I've had the exact same thing happening to me for a few weeks now.

One by one i've changed everything possible in the car, and nothing cured it until I took my PT out and used a different one!

Obviously, that ain't gonna be any help if you don't run a PT. Thought i'd share with you though.

Bizarre to say the least!
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Old 16-01-2009
Southwell Southwell is offline
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Could be a problem with the speedo not providing enough power on the bec? Just a thought, not had the problem myself though.
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Old 16-01-2009
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I've had 3 different speedos in, not all the same spec either. Anyways, touch wood, it's solved now.

Chesty, hope you can sort yours out ok....
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Old 16-01-2009
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Hmmmm....


NO steering
NO power

NOvak

sorry, i'll get my coat
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Old 16-01-2009
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you could be right there Ian, if you have a weak BEC on your esc, then it can manifest in weak/inop steerings etc.
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Old 19-01-2009
Chesty Chesty is offline
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After a weekend of racing with no problems (apart from my driving), it would appear that the NiMH batteries were the problem.

Only happened with my IB practice packs in, which although charged to over 9 volts were absolutely gutless on the track, seems they just couldn't deliver the current

Talking of batteries, I found one of my EastPower packs had a dead cell in it, is it true they can be restarted with a charger or even just a 12v?

Bloody batteries - BRING ON THE LIPOS
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Old 19-01-2009
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if your cells are peaking at a high voltage, then there is a duff cell(s) in there....
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Old 19-01-2009
Southwell Southwell is offline
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Quote:
Originally Posted by Chesty View Post
Talking of batteries, I found one of my EastPower packs had a dead cell in it, is it true they can be restarted with a charger or even just a 12v?

Bloody batteries - BRING ON THE LIPOS
Yes you can 'flash' them on a 12v but you could also get a cell explode in your face by doing it. Do this at your own risk.
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