XRAY - Model racing cars

How to adjust gear mesh?
The lower mount is fastened by countersink screws so that they will self center when you tighten them. The upper mount is attached using a pin so that there is no adjustment either and the engine probably has a little play but I am sure it is not sufficient to adjust between 15 and 18 or 20 and 23 pinion. Am I missing something.

Wes

no need to adjust gear mesh when changing pinions.

The best news I ever heard!!!

Thanks Danny.

Hmmmm, I noticed this as well (as the OP said) and while it's perfect for the stock gears, I don't see how this is going to work unless you change the pinions AND spurs at the same time, for ones that require the exact same gap. As for getting the best mesh possible with the stock gears, I found after a bit of playing around, that if you loosen the lower mounts, then put a folded piece of photocopy paper in the mesh, then tighten the mounts, then remove the paper, it's perfect, so there is obviously a few microns of play.

However, I would like an explanation as to how mesh is adjusted, I'm afraid it is simply not enough for me to say that 'mesh does not need to be adjusted', I can't see how this is gonna work in reality. Unless I'm missing something hugely clever in the design, could someone elaborate on this issue please?

Well it has something to do with the pitch of the gears/spurs and that the overall dimensions of both the Pinions and Spurs dont change even if it has less or more teeth. For Example the 15t and 18t 1st Gear Pinion are exactly same size, same with 54t and 53t spur.

Believe me it does work, i have changed to different pinions and now a different 2nd gear spur and i havent even touched gear mesh since i built the car.

How do they do this ? guess thats a secret ony Xray know, but i guess its also to do with alot of work and design

Ok, I'll take your word for it.

For now...

Thanks man.

Also there is a few ways to get the mesh perfect if you find its not quite as good as it should be.

What i did was install the top half of engine mounts to engine and do them up so they are still a bit loose, then when u have both of the top halfs of engine mounts attached to engine, screw the top half to the bottom half of engine mounts and do up tightly.

Then install engine into car using 4 screws under chassis, then you have a few mm of adjustment since the top bolts holding engine to top half of engine mounts are loose, so wiggle engine around until u have perfect mesh against gears then once this is done tighten the 4 bolts holding engine to top half of engine mount

Yeh, I did basically the same thing, but as I say I used a folded piece of photocopy to make sure, then when everything was tightened down, I took out the paper, and hey presto! Perfect mesh.

If the above is ture... then I have no idea what I'm doing wrong, I have gone though 2 sets of 59 gears (in less then 5 mins) and one 54 gear (I did not have a spare) in less the one lap.

Can someone help me...

I normally pinch the motor pinion gears tight to the spur gears, and let them "wear in" for a lap or two. On a different brand of car, this works very well and the gear after they wear in, always seem to have the prefect mesh

That's not a good technique for most cars and will lead to the stripping you are seeing. Try the technique described above for using the mountings, then to make absolutely sure, try my method of using a simple piece of photocopy paper folded in half, I promise it willl give you the perfect mesh.

wow 3 stripping gears in one lap there's must be something not right.

we're running almost over 4 hours with both pinion and the spur are still like new. can't say the same for belts because our track is not so clean we do have gear stripped when using 16-23 combination but after change to 17 the problem is gone. one tip be sure to check the throttle EPA on your tx, u dont want to bend the chassis when accelerating or braking