Originally Posted by
blackshark3
Dear Oleg,
Me and my friend together bought two A700EX from my local hobby shop early July, and since day 1 I've asked the hobby shop, who stock no parts for the A700, to order the gear diff upgrades ST23 ST26 and the metal gears. Now two months down the road, all I got are just promises that they would come some day.
During these times one car already ran but the first day it clipped a sidewall, the drive cup popped and the plastic gears shredded. As the parts are not yet arrived, I tried to make shift by using Spec R gears, coupled by your recommended modifications, including adding shims and putting a plastic stick to hold the drive cup. On the second day, the drive cup again popped, this time before the car even finish half the battery. The second car is still in the box, unassembled, just don't want to cannibalize it for parts, and even if we do, the gear just won't last for long anyway.
Frankly I am really disappointed on the gear diff design, it just ruined the whole car design. There was just nothing to hold the drive cup except for that flimsy o-ring, which is inadequate for today's high power motors. Couple with the extraordinary design of the car overall I would expect a more foolproof diff design, maybe with the ST23 and ST26 comes standard, or just make the shaft of the ST07 drive cup longer so that a pin could be used to hold it in place instead of having the ST20. I still remember when the car first ran it was so good, until the gear diff failed, it just ruined the whole experience. I tried things to revive the car, fix the gear diff, short of asking a machine shop to custom made two drive cups that could be pinned.
Anyway, I would be highly appreciated if you could check whether you received any orders from Hong Kong, and if so please ship that out ASAP. If there has been no orders from Hong Kong please pm me, I would have a word with my hobby shop and would order from you direct instead. Its just a shame for the car to sit gathering dust.
Thank you for your attention.
Regards,
Jason
Dear Jason
How may I help you and your friend in anyway?
You may contact me through my mail or pm me.
Over filling seems like the cause for diff half to pop out
Here is the step by step how to fill up the diff
1. assemble the diff and fill up the oil (dont worry about over filling at this step)
2. tighten the assembly, leave AT24 face up and not to insert ST07 on this end
3. heat the unit to operating tempeture (around 60' C usually work for me)
4. after the excess fluid comes out from the AT24 then clean it.
5. insert ST07 into the place slowly, more excess fluid may still come out.
6. pull out ST07 and repeat step 5 as needed.
7. Put two orings into ST07 or the trick Oleg mention before.
Now you have a diff complet with proper fluid level, this trick works with all other cars as well.
If you have time you can use vacumm pump that we use for shocks, try to pump the air out before step 4.
I hope this will help you to have more track time before your new parts arrives.
Thanks
Best regard
Wen