Sluggish Brushless

[DaveG28]

Hi All,

Have been running bruyshless for a few months now and very impressed, however put a new LRP speedo in my 501x today and it was very sluggish all day, slightly down on top speed but absolutely no acceleration. CHanged to my old speedo for the final and it was only slightly better (in my other car the old speedo flew!)

Does anyone know if this is most likely caused by esc, or motor, or batterys??

My cells are IB4200, a year old now, my motor is LRP 5.5 (done about 7 or 8 meetings), any help much appreciated!!

[josh_smaxx]

Is it bonded? If it is it may be loosing power due to being over heated maybe. Maybe a faulty rotor just waiting to go? Might not be the speedo.

[bigred5765]

open the can and u may find the rotor has fluffed up, clean it out and bin the bits,
if carefull and its not to bad u can retrieve whats left of the rotor with super glue and a cotton swab, or get a new one depends on money i guess

[Cockerill]

Are the two speedo's setup the same. I would guess that the new one is still in Lipo profile, put it on Nimh and it should be fine.

I've had my bonded rotor's vey hot (100C+) and they are still very fast so I doubt that the rotor temp. is the problem.

I would try the speedo profile first before you open the motor up because I have never seen what Carl mentions happen to a 5.5. Also worth asking, have you changed the sensor lead?

[super__dan]

Originally Posted by Cockerill

I've had my bonded rotor's vey hot (100C+)

You???

No way???

[Robbiejuk]

Definatly cells I would think. My Ib4200s are a year old now and definatley showing signs of fatigue, If i don't peak them for the first minute of the race there is no punch at all and then when it starts the discharge cycle the punch starts to come back by about the second minute it is back to normal. I also had an issue where off the line the car would pull off an then cut out but this was rectified by changing to nimh mode.

Got some Lipos over christmas and my car is now wheelying off the line and all the way down the straight so it obviously isn't a problem with my speedo/motor.

Try and borrow someone elses cells and I am sure you will see a massive difference.

[Chrislong]

Hard to diagnose without physically having it to mess around with.

Start with the basics - as you'll kick yourself if you replace stuff then find something simple was wrong....

Have you set the end points/is the ESC reaching full throttle?

How is the cars transmission, does it roll freely?

Is it geared right?

Take the motor apart, have the cotton windings come loose (I think the 5.5 LRP doesn't suffer this)

Try a friends motor, don't change anything else

How are your cells? equalise, charge and use straight away...

Try some borrowed cells



Can't think of anything else, hope you can cure it.

chris

[DaveG28]

I have left the same gearing and maotor sertup as all winter, so I assume the gearing os ok.

I did think of that LIPO issue, especially as it cut out at the start of one race, but changing to the nimh setting didn't fix this. but even once I made the setups more similar (punchy/aggressive) it made no difference. Also set it up with the tranny 3 times (I forgot to dothis with the first race properly, I assume once I reset end points etc tho it should be fine?)

With the cells, No matter how often I run/equalise them the cells equalise totally differently to each other now, it almost felt as if I was running 5 cell it was so sluggish, but I am guessing its long odds that all three of my packs would go at the same time? Is it weird as well that the LIPO cutoff came in at the start of the race as opposed to the end?

Dave

[Chrislong]

Originally Posted by DaveG28

I Is it weird as well that the LIPO cutoff came in at the start of the race as opposed to the end?

Dave

If you have a cell down, and the pack is essentially running on 5, then yes, the Lipo cutoff is likely to prematurely cutout your car as the voltage will be low.