RC Tank Warfare community hobby forum

I've found some Graupner Speed 400 motors on ebay. But from the photo there is no pinion mounted on them.
Could somebody tell me if taking the pinion off my old motors and placing them on these new motors will be a difficult job? I'd rather know now before I commit to buying them.
I don't want to damage any of the motors due to lack of intelligence

-x se7en x-

Hi there I've got some 400 motors on my tiger and I used the pinions off my old motors . Now it depends what motors you have got that the pinions are on! The gear boxes I got off forgebear had motors with pinions with grub screws holding then on! But the motor axels were splined as well making it hard for me to remove the pinions I ended up cutting the motor axels off and taping the pinions off ! Then I filed the pinion holes bigger so they would slide onto the 400 motors! I allso filed a grove in each motor axle so the grub screw had a beter hould and had less chance of slipping! These are very good motors and I would recommend getting them! Hope that helps!

Hi Se7en,

If you've got pushed on pinions, your unlikely to remove and put on the new motors. I did manage to get a pinion off but then bent the shaft on the new motor trying to push it on bye bye £6.50

If you've something like the mato gearbox Gary mentioned then it is easy to change the pinions as are held on with a grub screw.

Also I've spent last 6 months trying to find an alternative pinion to put on new motors. and this is the closest i've found so far
http://www.ebay.co.uk/itm/120850075106? ... 1439.l2649

Not 100% if perfect match as the gearboxes make a right scream, but it is a very low ratio gearbox and the motors are the Graupner 400 speed 6v versions so 18,000 rpm at 6v so probably spinning close to 20,000rpm with 7.2v battery so that probably would make anything scream

Ian.

A little gentle heat to solid metal pinnions will loosen them off enough to tap them off with little force and heat them up again to refit them. Remember to keep the heat on the pinnion and not on the motor can the shafts will stand quite a lot of heat but watch out for plastic parts

I like that Idea tankbear, much easier to buy the pinions and put them on knowing that a simple grub screw will hold it, then try and prize the pinion off and buckle the shaft of the motor. I've heard that the pinions are press fit and that you need a gear puller to remove them.

My gear system was from Welshdragon an Asiatam improved metal gearbox if I remember correctly and I didn't notice any removable screws on the pinion at all I do have a set of old motors which I could practise on removing with the heat technique.
To be fair.. I need more power put on the floor at low speed, because my tank has got a bit fat and I'll be damned if I'm sending him to slimming world or fat club as my sister fondly calls it.

What method would be the best to heat the pinion and spindle? Soldering iron? gas burner(cooker)? electric hob? or blow torch (I don't have one )

-x se7en x-

@Tankbear in that ebay link, how many teeth should I get? 10, 12 or 14
nm I used a bit of grey matter and counted the pins on my motor I went for 10

HI Se7en.

The Asiatam gearbox have pressed on pinions (10 teeth). To be honest I tried the heat removal and didn't work for me, and then how do you heat the pinion hold it and push on motor all at same time?

Gear pullers I might be wrong be think more aimed at smaller motors like slot cars (2mm shaft) as those guys change gears to suit race etc not certain if would work to well for larger motors where the more powerful motor requires a tighter fit.

As for teeth, 10 teeth is normal for the HL or Asiatam gearboxes more teeth will increase top speed but reduce torque and smaller would be the other way round.

Plus those pinions I posted come complete with a 1.5mm allen key which is a bonus if you haven't already got one.

Ian.

Thanks for the info tankbear
I wont bother with the heating of pinions and whatnot, I already have a handful of soldering burns I don't want anymore
I just bought the motors and the pinions off ebay, I'd heard a lot about these motors and they are supposed to be the bees knees

*Sightly off topic warning*
I don't suppose you know what ohm rating the pots are for the throttle on the heng long TX are? I only have to put the lightest pressure on the stick and my tank jolts forward Is there anything I can use to make acceleration a bit more smoother?

-x se7en x-

Not certain abouts the rating of the pot for the transmitter. Daft question, have you tried moving the trim to see if that helps?

Seems the trim got a bit lodged, I opened up the TX and sorted it. Its still not 100% but a little better

-x se7en x-

I found one of mine was well out, pair of pliers on the pot and other hand on stick to line them up. Seems to of worked.

Also is an idea to run motors in before installing
http://www.rctankwarfare.co.uk/forums/v ... =38&t=8796

Strangely it didn't mention it in the Graupner instructions when I got mine and I didn't, but found the motors just kept on getter better and better with use. So suppose running them in first means you start with best performance.

Ian.