HPI Bullet drive issue

[theboyfold]

Before I go off to my local RC shop, I thought I'd ask here. I have an HPI Bullet that has lost all drive. It used to run, but would cut out every few seconds. Then it would not respond to throttle inputs for a few minutes, but the steering would still work.

Now it's motor is responding, but the gears aren't turning. The gears twitch, but don't spin. There doesn't seem to be anything blocking it without taking it apart.

[cjs racing.]

Tried tightening the grub screw on the pinion gear?

[theboyfold]

Yep. Then I started to run out of mechanical knowledge!

[cjs racing.]

Is the motor spinning but gears not moving, or motor jamming up too?

I'm assuming it's the electric version.

Did you start with the basics, and make sure battery is charged, and re bound the radio, if it's 2.4

[cjs racing.]

Can't remember off top of my head, does that have a slipper clutch?

If so, it may need setting.

Edit, can only find the spec of the latest Flux model, not sure which version you have, but the new ones do have a slipper, if it's worn, or not set, the car wont move.

Edited by cjs racing. on Saturday 3rd March 13:48

[theboyfold]

The motor spins up, but then the pinion doesn't spin. It does have a slipper clutch.

I took it to a local RC Shop and they suspect that something inside the motor has snapped. The motor spins up, but there is no torque at all.

The other issue is that the car has a habit of cutting out, the steering responds, but the throttle doesn't for a few minutes. I've read this could be an overheating ESC.

The battery seemed OK, but was a little flat.

It might be a case of new motor and ESC, which isn't what I want to spend at the moment.

[cjs racing.]

Have to agree the ESC could be shutting down from overheating.

Strange one with the motor, be interested to see what's broken.

So the shaft that comes out the motor, that the pinion screws onto, doesn't turn when the motor spins?

[theboyfold]

cjs racing. said:

So the shaft that comes out the motor, that the pinion screws onto, doesn't turn when the motor spins?

Exactly this

[cjs racing.]

Possibly if the motor was playing up, that was causing the ESC to overheat, fingers crossed that a new motor fixes it.

[theboyfold]

Any suggestions on which motor to go for? My initial research suggests that a combo of motor and ESC is almost the same money as just motor.

The one in there now is 4300

[cjs racing.]

My money would be going here.

https://hobbyking.com/en_us/turnigy-trackstar-wate...

[theboyfold]

Thanks for all your help. That's half what I was quoted in my local shop for a similar setup.

[cjs racing.]

No problem, always glad to help.

[theboyfold]

Where are Hobbyking based? Is it a Hong Kong store?

[cjs racing.]

Hong Kong based, but have warehouses in, Europe, UK, and America.

Very reputable company.

The link takes you exactly to the right page to buy it from the UK.

Edited by cjs racing. on Sunday 4th March 22:12

[TurbosSuck]

That motor and speed controller is only suitable for 2s batteries, I think the car can take up to 3s unless I'm mistaken. Might be worth checking what batteries you have before you buy.

Edit: Sounds like the magnets on your original motor have delaminated.

[Pete Franklin]

Agree sounds like delaminated motor so time for a new one. I had similar issue on savage flux. Tried fixing it with jb weld but it kept delaminating. Expensive issue.

[theboyfold]

TurbosSuck said:

That motor and speed controller is only suitable for 2s batteries, I think the car can take up to 3s unless I'm mistaken. Might be worth checking what batteries you have before you buy.

Edit: Sounds like the magnets on your original motor have delaminated.

This is the battery, I think it's 2s

[Pete Franklin]

That's a 3s

[theboyfold]

Ta, I will have a look through the site mentioned above for a more suitable setup then