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syafiq
2010.11.13, 10:21 AM
i have crack on my main chassis and intend to replace it. before i do that i need know what caused of it so i can take a precaution the next time i play. so far my mini z never crash at all.
http://i787.photobucket.com/albums/yy157/moe-otaku/crack4.jpg

http://i787.photobucket.com/albums/yy157/moe-otaku/crack3.jpg

http://i787.photobucket.com/albums/yy157/moe-otaku/crack2.jpg

http://i787.photobucket.com/albums/yy157/moe-otaku/crack1.jpg

if you can see the rear chassis already bend a little bit because of the crack.
http://i787.photobucket.com/albums/yy157/moe-otaku/crack5.jpg

this is the modification i made so far.
1.front= one way 28t (atomic)
2.rear= solid axle 26t (eagle racing)
3.front tyre= chamber 3 degree (atomic)
4.rear tyre= toe in 1 degree (atomic)
5.all four use green spring (atomic)
6. center drive shaft rear spur gear (atomic)
7. aluminum universal swing shaft (atomic)
8. titanium light weight center main shaft (atomic)
9. x-speed motor (kyosho)
10. gear ratio 7.23
11. rechargeable battery (camelion)
12.aluminuim rear gear case (atomic)
13. the rest is stock (kyosho)

cowboysir
2010.11.13, 10:55 AM
my first thought was stress around the area from the motor...get a lot of heat from motor output?

You'll get better durability from an SP plastic chassis.;)

Eman
2010.11.13, 11:04 AM
My guess would be the heat from the motor. Kyosho motors get stupid hot. When you change the chassis, change to the SP chassis. You won't have to worry about cracking in the same area. However, the heat from the motor will help tweak the chassis eventually. If you stuck on using Kyosho motors slap some aluminum motor holders and heat sink on it. Good luck man!

EMU
2010.11.13, 12:46 PM
My initial guess would be collision damage would be the primary reason, in a weakened area of the chassis due to the heat of the motor. It is direcly where the side clips mount, and the force of collisions are excerted to the sides of the chassis as well as the front clip. Although, you state that you never crashed at all with this car, so it would probably be heat related as the motor will expand as it gets hot, and the X-Speed gets pretty warm even with a 7.23 gear ratio.

The heatsinks may cool the motor a little more, but they will transfer that heat to the chassis as well, which may make it warp in time. Since the motor is not in direct contact with the chassis, the head is radiant heat rather than conducted heat as it would be with the heatsinks. I do use them, but if the motor is VERY hot, you want to reduce temperature (change gearing/motor)instead of trying to dissipate it.

I have had a few chassis crack in the same way on the battery side, which was due to the batteries being a little too tight.

Definitely upgrade to the SP chassis. While I prefer the smoke grey chassis for handling, the SP chassis is much more durable.

Bodom
2010.11.13, 03:33 PM
My stock chassis cracked on the battery side. I suppose because of battery tension as EMU mentioned. Then I changed to SP chassis and had no problems with it. The interesting thing is that my old chassis continued to crack and break apart even though I use it only for Autoscale display chassis. :D
It's plastic gets old and is very vulnerable I suppose :)

Q t
2010.11.13, 04:14 PM
id have to go with what they said the heat will make the plastic weaker and also clear plastic has always been weaker then solid color plastics when i use to make gundam model kitsi once bought a clear limited edition kit everything broke when i tried to put it together thats y i like the sp chassis and the crack could be the wrong size motor spacer or battery but idk but thats just my experience with clear plastic

syafiq
2010.11.14, 03:28 AM
My initial guess would be collision damage would be the primary reason, in a weakened area of the chassis due to the heat of the motor. It is direcly where the side clips mount, and the force of collisions are excerted to the sides of the chassis as well as the front clip. Although, you state that you never crashed at all with this car, so it would probably be heat related as the motor will expand as it gets hot, and the X-Speed gets pretty warm even with a 7.23 gear ratio.

The heatsinks may cool the motor a little more, but they will transfer that heat to the chassis as well, which may make it warp in time. Since the motor is not in direct contact with the chassis, the head is radiant heat rather than conducted heat as it would be with the heatsinks. I do use them, but if the motor is VERY hot, you want to reduce temperature (change gearing/motor)instead of trying to dissipate it.

I have had a few chassis crack in the same way on the battery side, which was due to the batteries being a little too tight.

Definitely upgrade to the SP chassis. While I prefer the smoke grey chassis for handling, the SP chassis is much more durable.
i dont understand what you mean changing gearing. can you give me a suggestion for better motor?

dantep
2010.11.14, 02:16 PM
You might want to measure the length of the motor to see if that might have something to do with the chassis breaking. Also check if the motor mounts properly fit unto the motor, if they dont, it'll be a very tight fit into the chassis.

I did a quick check on the length of the 11 motors i have and they vary from 25.0 to 25.21mm!! The motor slot in the chassis is 29mm, plastic motor mounts are 2mm each. If the tolerances of the chassi, mounts and motor is not on your favor then it will add strain to the chassis.

I too have had a grey AWD chassis with cracks on both the motor and battery side. But I'm pretty sure I got them during the high speed collisions with walls, chairs, tables etc before i started racing on tracks.

herman
2010.11.14, 10:00 PM
all good points... to summarize...

probable chassis breakage causes (and solutions)
- heat due to motor (swap out to a cooler motor / change gear ratio)
- weak chassis to begin with (swap out to stronger sp chassis)
- chassis stress due to motor length / wrong motor plates (check motor length / motor plates)
- high speed collisions (don't crash :D - which is kinda hard not to do)

good luck and hope you get it fixed... :D

syafiq
2010.11.15, 08:36 AM
all good points... to summarize...

probable chassis breakage causes (and solutions)
- heat due to motor (swap out to a cooler motor / change gear ratio)
- weak chassis to begin with (swap out to stronger sp chassis)
- chassis stress due to motor length / wrong motor plates (check motor length / motor plates)
- high speed collisions (don't crash :D - which is kinda hard not to do)

good luck and hope you get it fixed... :D

i think motor length is the best description to what to my chassis. because if i remember correctly when i use it for the first time, the motor didnt fit to the chassis well so i force it down to fit in. i dont want to change my motor so anybody can solve this problem other than using sp chassis.

EMU
2010.11.15, 11:37 AM
Do the motor adapters fit on the motor all the way? Sometimes they are a little too tight, and make it difficult to fit into the chassis. I have had to modify the adapters slightly to get it to fit right. You want the motor to fit into the chassis easily, otherwise you are stressing the chassis, and it could crack again.

CharSiewBaos
2012.09.30, 08:44 AM
i was wondering what type of plastic the AWD sp chassis are made from. I purchased 3 this year and they all cracked in the same spot (under the battery pack). :mad: and i was wondering if i could glue it with a type of weld or cement.