Kraton :( First drive ended up badly!

[Kingpin]

Yeah I don't blame those outdrives for wanting to quit lol that looks like quite the load......was that 17 LB with the tires and battery? Seems like it would be more than that considering you have 5+ pounds of just wheels and tires there. Glad you are recovering though

Thanks.
It was without a battery and tires I think. I posted it here somewhere.
But the wheels aren't that heavy. They aren't metal rims in case you think that cause of the crappy silver paint job.

 

[N.Mango]

I wish I had a DBXL-E as a backup rig!

 

[Adiabatic]

I used to run Mugen truggies and while the outdrive steel is very hard and wear resistant, I'm not surprised it's too brittle to survive in this application. These parts are intended for <10lb nitro/4s powered cars with light racing wheels, not your behemoth of a machine.

 

[StephenSchandelmayer]

Thanks.
It was without a battery and tires I think. I posted it here somewhere.
But the wheels aren't that heavy. They aren't metal rims in case you think that cause of the crappy silver paint job.

I was just guessing weight based on prolines 24mm tires which are all about 1.5 pounds each. If its 17 lb without battery and tires......thats super heavy. You are looking at 22 pounds with tires roughly and maybe 24 with a battery? Lets say 21 to 23 pounds on the low side. Thats very heavy considering stock kraton 8s without battery is 24 LB

 

[SrC]

Heavy rig there.
Destined for the drivetrain to let go somewhere.

Like @Synchronicity stated, 1/8 rig platforms were truly designed for 4s running. 6s became the norm. Then 8s.....Many push these rigs way beyond their limits. Alloy really adds up quick in the weight department. The supposed added strength of all the alloy then works against you.
Then more crap happens out of the norm.
17 pounds is very heavy without Lipos and wheels. I would drop the punch down. (less initial torque) This might save some drivetrain wear. IDK for sure.
If the output Cup didn't shear off, something else would have. The stress of weight and torque had to give somewhere.

 

[Kingpin]

I used to run Mugen truggies and while the outdrive steel is very hard and wear resistant, I'm not surprised it's too brittle to survive in this application. These parts are intended for <10lb nitro/4s powered cars with light racing wheels, not your behemoth of a machine.

The internal gears are from the MBx6 which is a 1/8 which are drop in and apparently from all my research are higher quality from what I read here. Maybe the outdrives which look hefty as he!! are not. I still haven't torn it apart. If it's the drivers side outdrive again I'm wondering if I am having another issue as it would be the same outdrive as before.

I was just guessing weight based on prolines 24mm tires which are all about 1.5 pounds each. If its 17 lb without battery and tires......thats super heavy. You are looking at 22 pounds with tires roughly and maybe 24 with a battery? Lets say 21 to 23 pounds on the low side. Thats very heavy considering stock kraton 8s without battery is 24 LB

I just weighed the wheels and they are 1.10 lbs each and the 6s battery 2.3lbs. Hmm yeah heavier than I thought it would be. I have a postal scale at the shop and I'll put the whole car on it later to get an exact weight.
I have punch set at 0.
Maybe I should put the smaller pinion in.

I will say this. After all my research on parts and everything if this car doesn't work out I'm going to be a very unhappy person.
A $2k paperweight. shelf Queen is not what this car is intended for.

 

[StephenSchandelmayer]

The internal gears are from the MBx6 which is a 1/8 which are drop in and apparently from all my research are higher quality from what I read here. Maybe the outdrives which look hefty as he!! are not. I still haven't torn it apart. If it's the drivers side outdrive again I'm wondering if I am having another issue as it would be the same outdrive as before.

I just weighed the wheels and they are 1.10 lbs each and the 6s battery 2.3lbs. Hmm yeah heavier than I thought it would be. I have a postal scale at the shop and I'll put the whole car on it later to get an exact weight.
I have punch set at 0.
Maybe I should put the smaller pinion in.

I will say this. After all my research on parts and everything if this car doesn't work out I'm going to be a very unhappy person.
A $2k paperweight. shelf Queen is not what this car is intended for.

Well at a certain point all the beef starts to reverse its job and you sir have all the beef. Then you are throwing huge heavy tires at it that have a TON of grip therefore putting a huge amount of strain on parts. I would say get smaller tires, that will be a big weight loss and it'll be less grip so less stress. That doesn't mean you will have bad grip by any means, backflip 6s tires are 3/4 pound each and have great grip.

 

[Kingpin]

Well at a certain point all the beef starts to reverse its job and you sir have all the beef. Then you are throwing huge heavy tires at it that have a TON of grip therefore putting a huge amount of strain on parts. I would say get smaller tires, that will be a big weight loss and it'll be less grip so less stress. That doesn't mean you will have bad grip by any means, backflip 6s tires are 3/4 pound each and have great grip.

I have 2 other sets of 17mm tires and 17mm hubs if needed. Big Joes and Trenchers.

 

[Adiabatic]

The internal gears are from the MBx6 which is a 1/8 which are drop in and apparently from all my research are higher quality from what I read here. Maybe the outdrives which look hefty as he!! are not. I still haven't torn it apart. If it's the drivers side outdrive again I'm wondering if I am having another issue as it would be the same outdrive as before.

The internal diff gears will probably be fine. The outdrive probably broke again near the pin where stress is concentrated when you accelerate. I'm not sure you'll be able to find 6s size outdrives that will handle the rotating mass of your drivetrain and overall weight of the car. Might have to scale up to 8s parts.

 

[Kingpin]

The internal diff gears will probably be fine. The outdrive probably broke again near the pin where stress is concentrated when you accelerate. I'm not sure you'll be able to find 6s size outdrives that will handle the rotating mass of your drivetrain and overall weight of the car. Might have to scale up to 8s parts.

I don't think 8s parts would come close to fitting. 8s diffs I'm guessing are much larger. Even if they did fit dogbones and everything else wouldn't fit anymore.
I would think gearing down the 17mm tires and hopefully the M2c hardened outputs would work.
If not I'm throwing it in the back of the closet and never looking at it again. LOL

 

[SrC]

The internal gears are from the MBx6 which is a 1/8 which are drop in and apparently from all my research are higher quality from what I read here. Maybe the outdrives which look hefty as he!! are not. I still haven't torn it apart. If it's the drivers side outdrive again I'm wondering if I am having another issue as it would be the same outdrive as before.

I just weighed the wheels and they are 1.10 lbs each and the 6s battery 2.3lbs. Hmm yeah heavier than I thought it would be. I have a postal scale at the shop and I'll put the whole car on it later to get an exact weight.
I have punch set at 0.
Maybe I should put the smaller pinion in.

I will say this. After all my research on parts and everything if this car doesn't work out I'm going to be a very unhappy person.
A $2k paperweight. shelf Queen is not what this car is intended for.

I feel ya. Yeah she's over 20 pounds (full running weight), no doubt. What I guessed.
You will dial her in. I am sure. You used all the best drive train parts. And Not by accident. Punch at 0. You know the drill.
Nice rig there. The nicest I have seen. Might sound silly, but try a 4s pack if you have one, ( less power) just to stretch her legs out more easily. See how it responds. Testing how it drives. An easier break-in. Then up it to the 6s. Just an idea. Ultimately, she needs to be run on 6s however.
Good luck.

 

[Crunchy Gears]

I don't think 8s parts would come close to fitting. 8s diffs I'm guessing are much larger. Even if they did fit dogbones and everything else wouldn't fit anymore.
I would think gearing down the 17mm tires and hopefully the M2c hardened outputs would work.
If not I'm throwing it in the back of the closet and never looking at it again. LOL

It's a beautiful looking piece of kit man.

If the m2c outputs don't do it for ya and 8s cups are too long..worse comes to worse you could disperse some of your beef among other rigs.

Maybe if you can find some cool wheels and tires that are lighter I think would help alot for your cause. The just bash it chassis is a f*ck ton of glorious heavy metal. Paired with what looks like double thick shock towers it's just too much. The rest is inconsequential not enough weight difference one way or the other to matter really imo from what I can see.

Do the m2c drives and put some lighter wheels on it before you quit at least!

 

[Velodromed]

I don't think 8s parts would come close to fitting. 8s diffs I'm guessing are much larger. Even if they did fit dogbones and everything else wouldn't fit anymore.
I would think gearing down the 17mm tires and hopefully the M2c hardened outputs would work.
If not I'm throwing it in the back of the closet and never looking at it again. LOL

Naw man don’t give up. It’s too nice a car and you’ve overcome so much. Finish it! Maybe just compromise a bit on something’s to make it happen. Gear down, different tires…4s battery sounds like a good start off.
It’s a beautiful piece of work and I’ve enjoyed your build.

 

[edh]

what parts do you have exactly that people say is too heavy? i was looking at the mmx8s/1717 with beefcake and wonder if thats too heavy?

 

[Sandracer_NL]

what parts do you have exactly that people say is too heavy? i was looking at the mmx8s/1717 with beefcake and wonder if thats too heavy?

How much will your K6 weigh do you think? Are you planning to run 8s, because with two 4s lipo's it can add up quickly.
Most of us add a few pounds here and there (I'm talking about our RC cars ), which isn't a problem. But there comes a point that one part no longer can handle the weight and or power. You can fix that, but you run the risk the next weakest part will fail.
Larger and heavier tires put a massive increase of strain on the drivetrain components, a substantial weight increase of the car amplifies that even more, so be aware of that.

@Kingpin I hope running smaller /lighter tires will solve your problem

 

[Vietnemesis]

Sorry to hear about your past health issues. Glad that you are better and back at it.

You have a beast of a rig and I hope you figure out the weight / power to strength ratio soon. If not, have fun working forwards it.

 

[Kingpin]

So turns out the other side broke this time.
When the other side broke the first time I just replaced that one(drivers side).
It broke because I didN't have the ESC setup properly and I went from forward straight into reverse, NOT BRAKE.
I'm wondering if it damaged both outdrives and I should have replaced them both.

Maybe it was damaged also.
You can see in the pics how much more meat are on the Mugen outdrives compared to the M2C upgrades.
Either way I changed them both to M2C and I will try it again one last time.
If it breaks againbI will first go to the 17mm tires. If that doesn't work then I will change the pinion out also.
I did a total rebuild of the rear diff since the M2C parts fit differently and I had to figure out the correct shims.
Dropped everything in parts cleaner and started fresh I also went with lighter 100k diff fluid.

 

[Crunchy Gears]

So turns out the other side broke this time.
When the other side broke the first time I just replaced that one(drivers side).
It broke because I didN't have the ESC setup properly and I went from forward straight into reverse, NOT BRAKE.
I'm wondering if it damaged both outdrives and I should have replaced them both.

Maybe it was damaged also.
You can see in the pics how much more meat are on the Mugen outdrives compared to the M2C upgrades.
Either way I changed them both to M2C and I will try it again one last time.
If it breaks againbI will first go to the 17mm tires. If that doesn't work then I will change the pinion out also.
I did a total rebuild of the rear diff since the M2C parts fit differently and I had to figure out the correct shims.
Dropped everything in parts cleaner and started fresh I also went with lighter 100k diff fluid.

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Anyone's rc could have gears give up if they only had forward and reverse without brakes regardless of weight.

You might have drive train issues through out waiting to show themselves from that depending on how bad and how long it was that way. That sucks man

 

[Kingpin]

Anyone's rc could have gears give up if they only had forward and reverse without brakes regardless of weight.

You might have drive train issues through out waiting to show themselves from that depending on how bad and how long it was that way. That sucks man

The first time it happened was not really a drive. I set it on the floor in the house went forward slowly and then tried to stop and it went into reverse. Luckily it was at a crawl almost so I don't think any other damage happened. I then found out that even if you setup a Castle esc in the app you still have to do the basic sync first off or you will run into the problem I did not having brakes.

 

[Kingpin]

Run #2:

Using the M2C outdrives in the rear.
Still the same 19t pinion and 24mm tires.
Car ran for 10 minutes and ran amazing before one of the front outdrives broke.
It was another Mugen outdrive.
So my conclusion as someone else mentioned in this thread and is spot on is that the Mugen outdrives can't handle what I'm bringin to the table. They may work well as a stock replacement but not for this Beast.
Now I will be replacing the front outdrives and the center diff outdrives with the M2C ones. I think the center diff uses the same ones please correct me if I'm wrong.

Now on to some good news.
THE CAR IS BEAST.
Holy crap. I was doing wheelies all the way across the front of my acreage. Probably 100' before the wheels came down. It will do a wheelie from 1/4 or 1/2 throttle just the same.
Another pleasant surprise is my fitted 1/5 dbxle rear wing acts like the perfect wheelie bar and helps greatly to control the car with the wheels in the air.
My homemade front and rear mud guards work great and other than an odd piece of grass here or there it's pretty much spotless inside.

Negatives other than the broken output drives.
The car is not wide enough for the 24mm wheels.
It's way too high IMO and this hurts the handling. I felt it was real easy to roll over. I never did because I was taking it easy as I still haven't painted the body.
So I think I will be switching to the set of JustBashIt 17mm wheel (10mm) extensions and try the Big Joes on the old school centerlines.

Now I need to order the outdrives. Hopefully my shop has enough in stock. I need 4 plus spares.