[Ichabod]

The GT40 that came in the Top Gear set I got for my son two years ago (which led to digital tracks, building an actual table in the basement, the whole shebang), has always been a slow runner. I'm beginning to wonder if the motor is at fault, but I'm sure there are plenty of things to check that I haven't. I've sanded the tyres to give a great contact patch, and WD-40'ed them (I'm sure that's a verb). I've added weight here and there, checked connections.

At 50% power (SSD PbPro, SH, all that stuff), this car barely gets around the track. At 100%, it goes like the others at 50%. Similar in analog mode.

What else would be worth doing before I go the next step and try a motor from a good runner, or save myself some fiddling and try a brand new one?

 

[RikoRocket]

I suppose you've checked there is nothing binding or rubbing? Leave about 1/2mm side to side float on the rear axle, make sure tyres are clear of body. Else swap motor as you are thinking about...

 

[staglinger]

Hi
both my gt40's are slow since new sadly I chipped them before trying them thinking they would be great cars yes I know muppet
regards ade

 

[Ichabod]

Well that just took 4 seconds off the lap time! Thanks!
There was no float at all so I popped out the rear axle and took off a spacer I'd put in there which apparently had some binding effect. (And which I have no recollection of installing.)
4 seconds off, about 3 more to go for it to match the other Scalextric cars.
One thing I've noticed is that the guide is installed in such a way that the front tires don't really touch the track other than occasionally. Is this causing extra friction to slow the car down? It's effectively a tripod between the rear wheels and the front braids. I'm not sure how I'd raise the guide/lower the wheels though.

 

[RikoRocket]

No it wont be detrimental. You could lightly oil the braids and that might make a difference - you can then get proper stuff from pendles. Make sure the front axle spins freely as well, it will touch down in the corners and if it is even slightly stiff it will slow the car a lot.

Lubricate the rear axle bushes with sewing machine oil if your other half is not looking, do it on the running surface where the axle touches and also lubricate the sides of the bushes where the wheels will touch on cornering.

lubricate the motor spindle just at the bell end, never at the brushes end unless it really squeekes there.

lubricate the gears.

Now try and keep up with them with any of your other cars!

 

[Ichabod]

I use Inox on the braids and track.

So the GT at 100% power is lapping at about the same lap times as the other cars at 50%, which means it can at least compete in certain situations - thanks for all the input.

At 50% it makes the ideal car to give to the three year old boys who get excited when they see the track - it'll trundle around the lap on full power without getting into any trouble.

 

[RikoRocket]

OK, so change the motor, the binding may have overheated it and caused a failure.

 

[keysandslots]

Remove the motor, attach some leads to it, attach the other end of the leads to your track, dump the motor in a glass of water, and run it at full throttle for a few or 10 seconds or so. If there is a problem that can be cleared up this way, you will hear the motor rev up as it cleans out.

Remove it from the water, blow some air through it, give it a lube and then put it back. It might help, might not, but it sure looks cool having the motor run under water.

Randy

 

[Ichabod]

I think I'll try both these ideas -

I'll get myself a new motor (suggestions? Should I stick with Scalextric, or go for a slot.it or such like? I think my local shop has both, along with possibly some others in the bargain bin last time I looked).

I am also now intrigued at the idea of submerging a piece of electrical equipment and watching it spin. If there is some sort of improvement I may well re-install it.

 

[keysandslots]

They seem to be fine with water:

Randy

 

[RikoRocket]

I would suggest the Scalextric is your safe bet. But if you shell out for another make of motor try to keep it similar so that you don't have big change in performance between the cars

 

[chris99]

QUOTE (RikoRocket @ 17 Nov 2011, 19:57) <{POST_SNAPBACK}>lubricate the motor spindle just at the bell end, never at the brushes end unless it really squeekes there.
Which is the bell-end - the opposite end to the pinion?

 

[Coopdevil]

Ahem! It's endbell not bell-end.

What? I've no idea what you are talking about, Bell End is a place in Worcestershire. Ahem.

On a normal S-can (Scalextric style motor), the endbell is the plastic/nylon assembly at one end of the can. Scalextric and Fly cars are endbell drive in that the pinion is at that end, Carrera and Revell-Monogram are can-drive in that the pinion goes at the other end.

Coop

 

[RikoRocket]

ooops

freudian slip...

(I've probably spelled that wrong as well...)

 

[Ichabod]

I replaced the motor (remarkably easy and non fiddly operation, I was pleasantly surprised), and now the GT is among the faster of my Scalextric cars - probably in part due to the other stuff you recommended. It's definitely one of the more stable, due to its low height I'm sure.

I must have worn out the motor with my cack handed shimming of the axle, although as far as I remember it was always slower than the Porsche in the set, which is probably what prompted the shim in the first place.

Thank you for all the suggestions. I still plan to submerge the old motor when the mood takes me.