Low run times

[vtgrrrs]

I have had my Lunchbox a while no and have noticed my run times reducing. I only use 1500 ansmann batteries I got from Goldstar when I bought the package. I have swapped the battery for a new one and although run time has improved it's still not as long as it once was.

What could be the reason? It may have got slightly wet some time ago but not excessively.

[tamiya monkey]

Hi there, you mentioned you've got another battery, what sort is it, nicad or nimh and what capacity, also what charger are you using, this could be your problem if your battery is not fully charged.

Just out of interest what kind of runtimes are you getting and how quick does it feel.

[chris350z]

Check that all the wheels and everthing turn easily, are you using ball bearings?

[Butler]

Whats your charger?

[vtgrrrs]

The batteries I have are Ansmann Racing 1500 mAh NiCd. The charger is an Ansmann ac30 timer charger. I have so far only charged the batteries with the 30 min fast charge, the original battery a lot of times, only twice for the more recent.

It doesn't have ball bearings, I just assembled it with the orginals from the rere boxed set however the wheels still seem to be moving freely.

Thanks again.

[TA-Mark]

Ni-Cd cells will develop a memory if not fully discharged before being recharged or if not fully charged each time. This will shorten your runtime over time, and the life of the pack.

Timed chargers don't charge packs properly. Delta peak chargers turn themselves off when they 'feel' the battery is charged. Most delta peak chargers also have cycles suitable for Ni-Cd (Discharge to Charge cycle).

A set of bearings is cheap, make the model last longer, and increase your runtime by reduced load. Bushings need constant cleaning and relubrication, especially after being 'wet' or run in dirty conditions.

[vtgrrrs]

OK thanks. I will probably invest in some new bearings in the future. So it's probably worth binning the original battery by the sounds of it then? For lubricating the bushes (do you mean the motor or wheels?) what would you reccomend?

As for the charger, will it make a difference ifI use the 'trickle' charge option?

[TA-Mark]

OK thanks. I will probably invest in some new bearings in the future. So it's probably worth binning the original battery by the sounds of it then? For lubricating the bushes (do you mean the motor or wheels?) what would you reccomend?

Clean and lubricate the plastic bushings inside the gearbox (the ones that support the axles and gearshafts), and the ones in the front wheels (Use ceramic plastic safe grease). A few drops of light oil in the motor bushes (one each end of the motor) will keep the motor spinning freely.

As for the charger, will it make a difference ifI use the 'trickle' charge option?

Using the trickle setting is still a timed charge. The difference is that you are using the wall clock to time the slow charge instead of the ticker timer on the charger which switches to trickle after the fast charge timer runs out. The charger doesn't 'feel' when the pack is at capacity, so if the timer is wrong, the pack has either been overcharged or undercharged. Timed chargers should have been removed from the market a long time ago.

Full cycles of the battery can sometimes remove the memory affect. Full cycle = fully discharged, then fully charged. Ni-Cd packs will loose some charge overnight, and even more if left for a week, so the first run after the pack has sat for a few days will be a reduced runtime. Let the pack cool after the run, charge, let cool after the charge, then when used straight away it should show a full runtime.

Is the Ni-Cd pack warm to touch after the charge? They should be. If the pack is still room temperature after a charge, it is undercharged. (Ni-MH and Li-Po should not get warm after a charge).

[vtgrrrs]

OK, thats great thanks. Should help to get my run times up again!

[tonysmini]

My nimh always warm up just before they finish charging. I always thought that was them peaking at full capacity.

[digitrc]

My nimh always warm up just before they finish charging. I always thought that was them peaking at full capacity.

NiMH will get hand-warm (not hot) at the end of a fast charge. If they aren't warm, they are not charged and will need to be re-peaked.

To the OP - get rid of your timed charger. All it will do is cook your batteries. Get a peak charger. You can use a trickle charge, but it will take all night and the car will not feel fast.

[vtgrrrs]

At the minute I'm getting around 8 - 10 mins running time. Not great - I'm guessing a new charger and batteries are needed!

[OrangeSport]

8-10 minutes is not great. Admittedly my packs are 3000 (not 1500) but my Hornet and Holiday Buggy are both running 540 silver cans and will last 30 minutes of hard constant driving, and more (40+) of "playing" with pauses for the odd photo etc..

[TA-Mark]

10 minutes is about right for a Ni-Cd 1500mAh pushing big wheels and no bearings. I get about 10-12 minutes out of my 1400-1500 Ni-Cd packs, and about 15 minutes from the 1800 Ni-Cd packs in a 4WD buggy with full bearings (similar load).

Larger capacity batteries will give a longer runtime as Orangesport says. The Hornet and Horror (Holiday) Buggy have less load than the Lunchbox, so will run for longer on the same pack. Expect 20-25 minutes from a 3000mAh Ni-MH in a Lunchbox with full bearings.

Note that Ni-MH packs need a charger that is suitable for Ni-MH batteries (Delta peak with a Ni-MH program setting).