XRAY - Model racing cars

Hi,

I recently bought a used T2'008 from a guy at our local track.

It's a really great car, a real big step up from my Losi XXX-S.

I have been experiencing some weird problems with the T2.

For some reason, the main drive belt keeps flipping over on its back after a few laps. I then, flip it back, but the same thing keeps happening.

Is the belt to tight or is something else wrong?


Has anyone else experienced this problem?


I've ordered a new belt, hope this will help fix my problem.

A new belt would probably solve your problem.

Also check if the pulleys have no dirt or small stones stuck in them.

I'll try a new belt and see it that works... And I'll try to see if I cant clean out any dirt in the pulleys.

I had the same problem in the past with a new belt. Seems like it was twisted in the package & kept flipping over when I ran it (and it wasn't too loose either)...so I took it off, reversed it on the car & it never flipped again. Can't say for sure that it will work for you, but I've seen it work twice locally.

Denney

The front spool and the layshaft are sided so make sure thay have both been put into the car the right way round

[quote="Coach-Z"]I haven't mentioned it yet, but I really don't know that much about RC vehicles yet, so you've got me stumped here ...
quote]

Don't worry, we all start there!

Put the car on stand and you will see that you can counter rotate the rear wheels – ie turn one forward and one backwards.
If you can do that with the front wheels then you have a differential fitted to the front too. If you cannot then you have a solid axle, ie a spool, which XRAY call a Composite Solid Axle.

As I said, if you look at the three items you will see they are sided not symmetrical and it is important that they are sitting in the bulk heads the right way around. I was thinking that it could just be that your seller took the car apart to give it a good clean and made a mistake when putting it back together again.

I am also thinking that maybe your front belt is too loose which could be the problem. They stretch with age and there is a built in mechanism that lets you tighten them up – see page 12 of the 008 Instruction Manual.

Try this.
Put the car on a stand and with one hand rotate the spur gear so the front wheels move in a forward motion. Whilst doing this place the forefinger of the other hand under the front belt right where it starts to engage with the spool/front diff pulley. Apply a bit (not much) of upward pressure with that forefinger.
If that causes the belt to easily come off the pulley then I would say it is too loose. Or to put that another way, as people have differing views on belt tightness; if it comes of easily, given the problem you have, then to me that suggests it is worthwhile tightening the belt one notch on the adjustment system and seeing if that improves things.

Hi,

You can check your set screw in the pinion gear, this may be rubbing on the belt. A friend of mine had this problem with robinson racing pinions.

Hi guys,


Thanks for all your help, I really appreciate it.

So I've changed the belt finally, took me a while not having done it before, but its done .

With regards to what caused the problem I went through all your advice, one reply at a time and I learned tons about the car in the process.
It turns out though that if I wanted to fix the cause of the belt flip, I should have looked at the last post first.

A couple of weeks ago, the pinion gear came loose at the track. While trying to get it on again I lost the original set screw for the pinion gear.
I really did not want to go home at that time, so I searched through my pit box in search of a replacement set screw.
I finally wound up unscrewing one from a Robinson pinion gear I had lying around.

As it turns out that particular set screw was about 2mm longer than the original one, but it fit into the hole.
I didn't even consider the fact that the protruding screw could cause a problem, so I screwed it in at kept on racing...

A few weeks later the belt flipping problem started and the belt teeth also seemed to have been worn down in a funny way.

It was like a line had been cut down the middle through the entire length of belt and the teeth were worn down on the "inside" towards the motor side.


D'oh!!!! (Courtesy of Mr. Simpson, Springfield, America)

Long story short, I have now changed the set screw to a shorter version, so hopefully now with a totally refurbished car, belt flipping will be a thing of the past...

Once again thanks to all the people who replied to this thread, this is why the internet rules .

Glad to hear it is sorted Coach-Z! That is the way you learn