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kreidel
12-17-2006, 08:32 PM
I installed my new center dog bones and went out to try it out and found that my front and rear diffs are also blown. I think that this buggy might be alittle too fragile. Is it possible that I received a lemon or is this a common problem? I am sure a center diff would make the drivetrain wear mininal but is there any suggestions in the mean time?

RC_KAOS
12-17-2006, 08:43 PM
Is this the GP or EP?

Cheers

gazzer55
12-17-2006, 10:00 PM
The GP doesn't have a center diff so i'm assuming its the EP. The differentials are quite weak on the H8. I upgraded to the 3 racing heavy duty front and rear ball diffs and they didn't hold up at all. I just installed some half nine metal diffs but havent been able to run them yet as i'm waiting on a new wraith motor. I think next to be changed is the center diff as it unloads to the front wheels too much. If I were you I would spend a bit of money to make sure the drivetrain holds up in the long run and i'm sure you'll be happy with this buggy.

kreidel
12-18-2006, 12:39 AM
I am sorry I wasnt more clear. I have a GP and the center dog bones had the pins wear out so bad they were slipping in the drive cups. I replaced them with new ones but when I went out to run my buggy I noticed only the front tires were pulling. I inspected it closely and found the rear ring and pinion were stripped out. So I emptied most of the fuel out of the tank and restarted it to burn the remaining out and within 10 seconds the car stopped moving but the engine was still reving. I looked and found that the front ring gear and pinion gear were also stripped.

halfeight0to60
12-18-2006, 03:47 AM
As usual pics would help tremendously. Are the metal teeth ground down or completely broken off? Also did you hit something solid full throttle? I hope this isnt going to be a "normal" occurrence or I might change my mind about buying more kyosho

kreidel
12-18-2006, 11:43 AM
I can't take pics, sorry. The teeth are worn down with less than 12 tanks. I did hit some jumps and needed to use throttle to correct in air for landings but never a full throttle landing.

gazzer55
12-18-2006, 06:37 PM
This is worrying! I spent the money on the half nine diffs because I wanted some diffs that would last. What exactly stripped was it just the pinions?

kreidel
12-18-2006, 07:41 PM
Mostly the rings but the pinions are almost gone also.

MGTfix
12-29-2006, 07:19 PM
The diff gears seem to be fine as long as you don't goose the throttle while landing a big jump, I drive it more like an electric car. The 09 jumps and flies alot better than the electric version, not as nose heavy.

FHM101
01-19-2007, 04:53 PM
I think next to be changed is the center diff as it unloads to the front wheels too much.
If you are running an EP and using your center diff cover, you can make it stop unloading to the front. Get some silicone paste, some 10x12x.2 shims, and a 4x7x2.5 bearing. Strip and clean the diff, then reassemble it, replacing the little center spacer with the bearing, and packing it with the silicone paste. The stuff I use is blue and when I'm done the diff looks like a rounded blue blob with outdrives sticking out. When you mount the diff, put a shim in both the front and rear bearing bosses in the carrier and assemble as usual only put the screws in semi tight and work the diff a little, then tighten it up and make sure it's still working smooth. It will feel MUCH tighter than what you are used to, maybe even a little notchy if you are using fresh gears, but don't worry. Put it in the car and give it an easy battery pack and you are good to go. After a few race days, open the cover and pack in some more grease. I built my diff this way right out of the box and along with a modded stock slipper have been running it for almost a year behind a Hyperion 5000 with a 12T pinion and both are still working just fine. It's been run with the stock driveline for about half of that time and the other half was with ST diffs, MIP CVD's, stainless outdrives, and steel center shafts, and has worked great. It makes the buggy jump like a small 8th gas buggy, very neutral in the air. The only difference between it and 8th buggy is you don't need to use brake to correct the mini in the air, just throttle or coasting. It also keeps the center from unloading to the front. The key to the whole thing though is to run the cover as it allows you to keep enough grease in the diff. You will need to service it from time to time to keep the grease clean, but that's about it.