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minimanintaiwan 12-26-2006 10:31 PM


Originally Posted by H I
What cause gearbox teeth to chip off on mini? I’ve replaced them heaps of times in last few races, I’m talking once every 2-4 meeting. Wasn’t like this before. I’ve checked pinion and diff but no damage at all. Just middle gears and I can’t see any rock or any thing like that inside. I’ve tried –lube gears – no lube –silicon splay all same result. I use gear diff build as per instruction with AW grease inside (not tight at all)

1 - Check universals, make sure grub screw is tight and pin holding shaft to axle is flush. Sometimes it works its way loose and your assembly gets loose but is still in tact. This can cause sudden but subtle stops when in motion and making turns. These abrupt stops can put pressure on all the gears.

2 - Check motor is mounted properly and pinion is tight.

3 - Check screws holding chassis together. They may be in but loose and not holding chassis tightly together

4 -check all bearings.

H I 12-27-2006 01:07 AM


Originally Posted by Z-Mann
a crash is all it takes, so dont crash :lol:

Can't help running into your car. Your mini is like magnet :lol: :lol:

Thanks minimanintaiwan. I think you may be spot on about universals. That pin use to come loose all the time. I've been using thred lock on grub screw but pin still comes loose. Any tip on that?

minimanintaiwan 12-27-2006 01:46 AM


Originally Posted by H I
I think you may be spot on about universals. That pin use to come loose all the time. I've been using thred lock on grub screw but pin still comes loose. Any tip on that?

I use threadlock too, but it does come loose. It's always the same one as well. Maybe a manufacturing thing. I just check it b4 and after each run now. Just turn tires all the way left or right and rotate tires and look for the pin and see if its flush or out on one side. Pain in the ass but better than replacing gears all the time.

Z-Mann 12-27-2006 02:44 AM

[QUOTE=H I]Can't help running into your car. Your mini is like magnet :lol: :lol:

the reason you run into my car is cause you run on inserts :lol:

rccardr 12-27-2006 04:23 AM


What cause gearbox teeth to chip off on mini? I’ve replaced them heaps of times in last few races, I’m talking once every 2-4 meeting. Wasn’t like this before.
Crappy plastic now used in the gears. This is something we noticed about two years ago and it hasn't improved. I just buy a half dozen or so at the beginning of each season and replace them before every TCS regional.

foampervert 12-27-2006 05:07 AM

gear snapping
 

Originally Posted by H I
What cause gearbox teeth to chip off on mini? I’ve replaced them heaps of times in last few races, I’m talking once every 2-4 meeting. Wasn’t like this before. I’ve checked pinion and diff but no damage at all. Just middle gears and I can’t see any rock or any thing like that inside. I’ve tried –lube gears – no lube –silicon splay all same result. I use gear diff build as per instruction with AW grease inside (not tight at all)


hiya HI!

do you use the regular gear shaft, the hollow metal shaft or carbon shaft for the centre gear?

the reason i ask is that if it's breaking, it could be because the gear shaft is slightly bent or it flexes during hard acceleration, thus causing more pressure on the gear teeth surface and chipping them. roll your gear shaft on a flat surface ( glass tabletop? ) and make sure it isn't bent.

i've been using the hollow metal shaft from the bearing pack. and so far, no gear chips at all.

it'll also help that you use a ball diff instead of a gear diff. a ball diff will allow some slip when your car impacts something. a gear diff has no give at all if both wheels are planted to the ground.

you might also like to check your gearbox halves ( chassis halves ), make sure the holes where the shafts fit into are not elongated due to wear and tear.

i dunt really think lube is gonna help all that much. most racers just skip lubing the gears so that the gears turn more freely. but just in case you really do wanna lube up your gears, use the lightest grease there is, dunt use thick, viscous grease on gears, it causes more pressure and wear.

-alexander

Customworksking 12-27-2006 07:23 AM

car gear
 
I wonder R U running a stock 540 motor"silver can" ? I run a gear diff shimed till its locked like a spool or just loose enough to get me throu TCS tech been this way for 3 years now with no chips but I only run silver can motors....

tamiyarcracer 12-27-2006 09:29 AM


Originally Posted by H I
What cause gearbox teeth to chip off on mini? I’ve replaced them heaps of times in last few races, I’m talking once every 2-4 meeting. Wasn’t like this before. I’ve checked pinion and diff but no damage at all. Just middle gears and I can’t see any rock or any thing like that inside. I’ve tried –lube gears – no lube –silicon splay all same result. I use gear diff build as per instruction with AW grease inside (not tight at all)

I found when running the gear diff, I chipped my gears, it is from being on power when the car gets in the air, then hits the track again with all the traction of the tires, something has got to give. Try a Ball diff, most of the time it will slip a little before the teeth chip.

Z-Mann 12-27-2006 12:21 PM

we run tamyia rs540 which latley can be advanced, :eek: so wit the extra punch from the newer batts the gears would suffer more.i guess u have to be easier on the throttle.i found its more due to a sudden on power impact or running a crazy motor....yeah your right the plastic is crap.i usually boil em for 15min or sometimes coat them with a thin epoxy resin which seems to work, though after time they do need replacing.......... not a huge expense, still mini racing is cheap and much fun

tamiyarcracer 12-27-2006 12:24 PM


Originally Posted by Z-Mann
we run tamyia rs540 which latley can be advanced, :eek: so wit the extra punch from the newer batts the gears would suffer more.i guess u have to be easier on the throttle.i found its more due to a sudden on power impact or running a crazy motor....yeah your right the plastic is crap.i usually boil em for 15min or sometimes coat them with a thin epoxy resin which seems to work, though after time they do need replacing.......... not a huge expense, still mini racing is cheap and much fun

Again try a ball diff. I never chip gears with a ball diff even with 23t motors

Z-Mann 12-27-2006 12:28 PM

i found ball diffs wear out the drive cups to easily plus they cost a lot more and are inconsistant

H I 12-27-2006 01:43 PM

foampervert , I use carbon shaft. I thought carbon don't bend :confused:
I think I'm going back to dog bone and ball diff. If that don't fix problem I just have to buy another mini :D

rai13 12-27-2006 04:32 PM

mo3 body
 
tony

i just found some hpi mini 225 mercedes a-class bodies. I was wondering if the'll fit the mo3 and if they'll clear the servo?

thanks
rai

GreaseMonkey 12-27-2006 05:58 PM

Is there any way you can get an M04 chassis down to a short wheel base? My main issue is that there's very few RWD bodies available in the 225mm wheel base so if I can shorten it. I won't have to worry so much about getting new bodies when the time comes.

tony gray 12-28-2006 12:33 AM

The HPI Merc A Class will fit an M03 easily Rai, I didnt list it in our site because it hasnt been available for years..

SWB M04? I dont think so. Not that I've ever seen. At 210mm it'd be even more of a handful!
There used to be a Kai carbon conversion for the M04 but I think that was 225 as well. I think you'd actually have to make one.
Something similar to the HPI M02 conversion that we have on the website would work.


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