Power Loss Question

[giftacrylic]

I run a X1-CRT geared 9/46 on a 9920/8XL combo on 5s lipo (MaxAmps 6000 mah). The problem of power loss occurs when approaching a long triple jump. The loss is only for a fraction of a second. Now, it only seems to occur when I am actually on the ramp, it does not occur on straightaways under very hard acceleration.

If I ease into the thottle, land the double and roll the triple, it will never occur. My solder joints are good and I am using a Dimension Engineering LVC.

Please help if anyone has experienced this problem.

[glassdoctor]

Sounds like you are hitting a current limit on the 9920 or more likely a low voltage cutoff?

It must do it under some other situation also, like landing wide open throttle, or coming off a corner on a high traction area???

Does this mess up clearing the triple? Does it happen when you start to accel toward the jump, or when you hit it?

[giftacrylic]

Only approaching the takeoff actual ramp (at the base of the ramp under throttle). After the slow turn into the striaght, I yank the trigger to WOT and no problems.

And yes, It will make me land the double and roll the triple.

Are we talking about a single 5s lipo or are you running 2 in parallel? If you are running 1p does the battery really heatup towards the end of the run?

[giftacrylic]

2s & 3s in series. After 15 minutes under track conditions (hard thottle and hard brake), the batts only heat up 20 degrees above ambient . So I am not pulling on the batts too hard and that is why I am confused.

[glassdoctor]

Sounds very odd... I would look very close at all connections/solder joints and try taping all the wires in place so they can't bump around and see if that makes any difference.

Try using a capactior on the reciever, like the $6 Spektrum one.... just in case it's the rx seeing a voltage drop.

Can you tell if it's a total loss of power, or just a "bogging"?

[giftacrylic]

It happens so quickly, it is hard to tell. All I know is that my acceleration is greatly dimenished, and then kicks back in (my trigger pull remains a constant).

I will take your advise and make sure that all wires are shielded and secure.

Maybe I will take some video tomorrow.

[glassdoctor]

I have seen simple things like a bad on/off swtich mess things up... but this happens at the same point in on the track which is weird...

[Patrick]

Is it a radio thing? I sometimes had glitching problems at certain places in the track. Where I stood on the rostram affected it too. Since I got a spectrum it hasn't happened (was only using the stock traxxas radio before).