Outcast Tired of blowing diffs with the XLX2 and 1100kv!

[Armarookie43]

The problem is arrmas aluminum diff case. It lacks the 4 keyed pins so the M3.5 diff bolts will take all the load and snap at the head. As others mentioned upgrade to the vitavon V2 diff case, it has 4 pins and M4 screws making it much more durable. Vitavon provided short M4 screws so i used some longer 12.9 grade ones with blue TL as the threads are deep enough.

OK. I might do it. Now I just might have to see what I can do with the center diff. I'll probably use brake cleaner instead of the fluid I was using. Even though I've done both. Thanks

 

[Licklobster]

stake the screws.

 

[Armarookie43]

stake the screws.

I'll lower the power on the XLX2. It will probably help. So hit the bolt head with a chisel and hammer? The case too? I'm weary of hitting that Arrma monkey metal too hard. The head on those bolts breaks if you look at it wrong

 

[Licklobster]

You swage the case metal into the screw head. The mechanical lock/interference prevents the screws from ever backing out on their own. Takes 10 seconds to stake all four.

 

[Moirae]

I replied to you in the traxxas xrt thread but I think it's definitely your xlx2 combo contributing to your problems. I took my tp motor out and put in the 2028 1100 I bought from someone here on the forums. That motor is stupid powerful. I had to turn my punch control to 70% because even trying to do a wheelie I was hitting standing backflips and my truck started making noises I never heard it make before.

 

[Armarookie43]

I replied to you in the traxxas xrt thread but I think it's definitely your xlx2 combo contributing to your problems. I took my tp motor out and put in the 2028 1100 I bought from someone here on the forums. That motor is stupid powerful. I had to turn my punch control to 70% because even trying to do a wheelie I was hitting standing backflips and my truck started making noises I never heard it make before.

I was thinking about doing 70% punch control and lowering the power of the XLX2. Do you think it would be the same as putting a smaller motor? Right now it's at full power and punch control at 25%, which generates 12 HP. Honestly, I don't feel that I need that much HP

 

[Moirae]

I was thinking about doing 70% punch control and lowering the power of the XLX2. Do you think it would be the same as putting a smaller motor? Right now it's at full power and punch control at 25%, which generates 12 HP. Honestly, I don't feel that I need that much HP

I think it's still better than a smaller motor but I don't know for sure. Even at 70% control I was still flipping on my back when I tried to do wheelies. I feel like I could even go to 75 or 80 and that is crazy to me. I'm surprised you don't break even more stuff with 25%

 

[SrC]

I'd be curious after running it really hard and then shoot a temp gun on the diff case and see what the temps are.
You have to get red Loctite pretty hot to make it break the bond. Surely the diff is not getting that hot, but just curious about what temps it is reaching.

Thicker fluid would help reduce the temps, bu this changes the front wheels unloading the power and the overall handling. It seems like M2C or some other brand needs to make one with larger screw provisions.

My 6s center diff got to 212F and it melted the diff to molten gears and plastic, The oil turned to a black Tar. I'm sure any TL would surely melt down at 212F. That's well over the boiling point.

I was thinking about doing 70% punch control and lowering the power of the XLX2. Do you think it would be the same as putting a smaller motor? Right now it's at full power and punch control at 25%, which generates 12 HP. Honestly, I don't feel that I need that much HP

Tame it down a bit Why not. If you can. Makes it more driveable.

 

[Armarookie43]

Over a year. Haven’t opened diffs up yet. That is a winter thing. 10+ packs through it.

What tires were you using. Recently I put some Pro-Line trenchers 4.3. They are amazing for stunts and they are very durable. No worries about regluing and all that. But they are heavier and bigger than the stock tires and duratrax lockup x tires. I wonder if that doesn't help?. The trenchers are in the middle :

I think it's still better than a smaller motor but I don't know for sure. Even at 70% control I was still flipping on my back when I tried to do wheelies. I feel like I could even go to 75 or 80 and that is crazy to me. I'm surprised you don't break even more stuff with 25%

Yeah but not only am I going for 80% punch control. I'm also going to reduce the power to the lowest setting. I'm thinking about going back to the Duratrax lockups tires, since they are smaller and a bit lighter than the huge trenchers. The problem is that this heavy beast loves to crack those rims.

 

[Armarookie43]

Don’t reuse the gears! Even if they look good - chuck em out!

I put vitavon cases in my Kraton 8s with xlx2 and 2028 1100 castle.

No issues.

https://www.ebay.ca/itm/28490907961...CdB2YqORAu&var=&widget_ver=artemis&media=COPY

Well everything on the center diff was OK except the internal gears and loose bolts on the outside. So I reused everything except the internal gears. I had an extra brand new outer diff and I stole the gears from that one and threw them in my center dif since all the internal gears are the same in all 3 diffs. I used red loctite and I was done last Friday around 6 pm. It's Monday now. So I'm going to use the same huge tires but will have punch control at 80% start power at low, maximum power at 50% I'll run it around at the park and I'll get some data to see if I can lower the 12HP that this crazy system was generating. I'm heading towards more and more conservative numbers, since I'm tired of destroying my stuff TBH. It was fun, but very expensive and I can't afford it. I never could TBH

 

[SrC]

1/5 8s line rigs are very costly. Parts are double $$ that of 1/8 rigs. 30+ pounds running weight is aprox. double that of most 1/8 rigs.
However, it is still considered Inexpensive compared to most other mainstream brand 1/5 rigs .
Arrma just used poor materials to keep the price point low where it is. Better metals and plastics would make a huge difference.
With the subpar materials, it should have been a much lighter platform. Using a better balance of weight to the materials used.
There is no excuse for diffs unable to handle the weight if it's a properly designed rig.

 

[Armarookie43]

1/5 8s line rigs are very costly. Parts are double $$ that of 1/8 rigs. 30+ pounds running weight is aprox. double that of a 1/8 rig.
Is what it is.

You are totally correct. As far as upgrading goes Xmaxx vs the Arrma stuff, the Xmaxx makes more sense to me personally to upgrade. Way less trouble since it's around 5+ pounds lighter after upgrading. The 6s line is way better for upgrading and running etc

 

[Armarookie43]

Here are the results. With punch control at 80%, start power at low and Max power at 85% (anything lower is too slow when I go below 85%), I got 47mph off road, which is acceptable. My Mojave EXB with the Spectrum 6s system from the Felony hits 50 MPH for comparison off road. I can still wheelie only if I want to. But if I start slowly, it just takes off planted, which I totally prefer. So I'm going to roll with it like that. All the diffs are fixed now and, to me, it's just as fun than before, but more controllable. Before, I would do a standing backflip if I wasn't careful. Now I just do a wheelie if I do full throttle. Wish me luck!

 

[Armarookie43]

And I'm not ever doing that self riding crap again ! That really messes up things. I'll just do the walk of shame, like I did today with my Mojave when it flipped over half a block away

 

[Armarookie43]

Run #2 results : I ran the truck non stop and got 8 minutes of run time with the 8000mah 120C HV graphene PW batteries with the 30/47 gearing. I saw that the XLX2 Brought down one of the cells to below 3v, which is not good . The ambient temp was 70F so it was cool outside. The batteries didn't get too got to the touch, but I forgot to measure the temp there. I'll do it again tomorrow. The motor temp was around 144F maximum with no fans on. I used to be able to eliminate the auto lipo and set the voltage myself to prevent too low of LVC, but for some reason, Castle only allows up to 14V total. I don't understand why they did that. I used to set the Voltage to 28V, which is 3.5 x 8 = 28V. I'll probably set the auto lipo to more than 3.5V per cell then.

 

[Moirae]

Run #2 results : I ran the truck non stop and got 8 minutes of run time with the 8000mah 120C HV graphene PW batteries with the 30/47 gearing. I saw that the XLX2 Brought down one of the cells to below 3v, which is not good . The ambient temp was 70F so it was cool outside. The batteries didn't get too got to the touch, but I forgot to measure the temp there. I'll do it again tomorrow. The motor temp was around 144F maximum with no fans on. I used to be able to eliminate the auto lipo and set the voltage myself to prevent too low of LVC, but for some reason, Castle only allows up to 14V total. I don't understand why they did that. I used to set the Voltage to 28V, which is 3.5 x 8 = 28V. I'll probably set the auto lipo to more than 3.5V per cell then.

I reported that as a bug to castle on the app and on the google play store. I don't know why they changed it but it was the update that added data logging to the app. I actually value the voltage cutoff more than being able to read data logs in the app so I've been using an older version of the app that allows me to set cutoff.

Took me a little bit to find the android file for the older version but I got it. If you're on an android I can email it to you or something if you're interested.

 

[Armarookie43]

Has anyone tried these out yet? They look good. Thoughts? Or just bite the bullets and get the more expensive vivaton one? I only need one. Or two.

https://www.ebay.com/itm/2653345371...2mtILn0RTS&var=&widget_ver=artemis&media=COPY

 

[Licklobster]

HR diffs are fine, I run em. It's almost a carbon copy of the factory plastic part.

 

[SrC]

If it were me, Vitavon all the way.
No questions.

 

[Armarookie43]

HR diffs are fine, I run em. It's almost a carbon copy of the factory plastic part.

On your 8s rigs? How about the bolts? Are they the same size? Thanks

Run #4 went fine today. I noticed that after not using the auto lipo function, and setting the LVC to 28.2V manually, the lowest one of my cells went to was 3.65V and the batteries lasted 15 minutes since I took it a bit easier. I also went to 100% punch control and it still wheelies if you slam on the throttle. Despite only being 67F outside, those PowerHobby batteries still got to around 144F. Almost non stop driving though. I'll go throw this thing off some jumps tomorrow. Then I'll probably check the diffs, since this would be like run #5.

I reported that as a bug to castle on the app and on the google play store. I don't know why they changed it but it was the update that added data logging to the app. I actually value the voltage cutoff more than being able to read data logs in the app so I've been using an older version of the app that allows me to set cutoff.

Took me a little bit to find the android file for the older version but I got it. If you're on an android I can email it to you or something if you're interested.

Yeah so the LVC is settled, but when you go to the previous app like we did, there's no way to access the data logs on your phone through the older app. So I'll probably just update the app and will not touch the LVC settings there. Thanks again!
At least for me, 47mph is not slow at all :