Kraton k6exb 'beefcake'

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, and others.

dqb

Very Active Member
Build Thread Contributor
Messages
91
Reaction score
222
Location
Texas
Arrma RC's
  1. Kraton EXB
  2. Vorteks
First off, a big thank you to everyone on the form for sharing such great information and the mod's for maintaining a wealth of info - as a new builder I was able to get through entire build without having to ask any questions.

6sEXB / Castle 1717 1650kv / MMX8S / M2C / PPS / JBI / ALZA / GCRC

TLDR Pic:
IMG_1826.jpg


The build in chronological order:
Planning
IMG_1652.jpg

Phase 1 start
Roller arrived on mother's day, thanks FedEx :rolleyes:
IMG_1650.jpg

Parts laid out for assembly
IMG_1651.jpg

Was too excited to get started and forgot to take a 'before' pic
IMG_1658.jpg

Fully broken down
IMG_1674.jpg

PPS motor mount 🤤
IMG_1691.jpg

Reassembly
IMG_1696.jpg
Phase 1 complete!
IMG_1720.jpg


After several packs I identified the following items to correct in Phase 2:
1. My makeshift servo mount extension was twisting / not going to work long-term
2. Motor was quickly getting to ~165 temps even with 18/50 gearing and would need fans
3. Tires were good but not great
4. MMX8S fan already broke
5. Spektrum tx/receiver felt slow and was a pain to switch between cars (with and without gyro)
6. Lots of un-necessary wiring

Phase 2:
JBI mount was a pain to get in; even after prying it into place I found the stock screws were ~2mm too long and need to file them down as I didn't have any of correct size:
67521515599__F6024C63-93D3-437A-924B-22E7799945A5.jpg

I went with with K8 heat sink with some .5mm thermal pad to make the connection
GCRC 'Maximus' (50mm) motor fan would not fit so cut the body for a cold-air-intake kind of thing
IMG_1821.jpg

GCRC 'Typhoon' ESC fan required different screws than the MMX8S so used an M3 tap to get it together
IMG_1861.jpg

Able to stuff Flysky FGr4 and castle bluetooth in the stock box.. barely
IMG_1884.jpg

Phase 2 result:
IMG_1875.jpg

IMG_1887.jpg


Phase 3 will be mostly cosmetic/reliability and will begin when I have a significant breakage (already stockpiling parts 😏).

Overall very pleased with the build, averaging ~130 temps in 90+ ambient on 20/50 gearing and handles great. Full weight comes in at 15.4lbs. Only regret was not including ceramic bearings in phase 1; now am faced with the daunting task of tearing everything apart to mark project 'done'. Only other regret was not building sooner.
And for those interested here's my gearing on 6s with backflips. I haven't GPS'd it yet and I don't really care to, but I think the 46mph calculation below is very conservative.
IMG_1889.jpg
 
Last edited:
First off, a big thank you to everyone on the form for sharing such great information and the mod's for maintaining a wealth of info - as a new builder I was able to get through entire build without having to ask any questions.

6sEXB / Castle 1717 1650kv / MMX8S / M2C / PPS / JBI / ALZA / GCRC

TLDR Pic:
View attachment 220634

The build in chronological order:
Planning
View attachment 220637
Phase 1 start
Roller arrived on mother's day, thanks FedEx :rolleyes:
View attachment 220632
Parts laid out for assembly
View attachment 220639
Was too excited to get started and forgot to take a 'before' pic
View attachment 220643
Fully broken down
View attachment 220645
PPS motor mount 🤤
View attachment 220646
Reassembly
View attachment 220648Phase 1 complete!
View attachment 220650

After several packs I identified the following items to correct in Phase 2:
1. My makeshift servo mount extension was twisting / not going to work long-term
2. Motor was quickly getting to ~165 temps even with 18/50 gearing and would need fans
3. Tires were good but not great
4. MMX8S fan already broke
5. Spektrum tx/receiver felt slow and was a pain to switch between cars (with and without gyro)
6. Lots of un-necessary wiring

Phase 2:
JBI mount was a pain to get in; even after prying it into place I found the stock screws were ~2mm too long and need to file them down as I didn't have any of correct size:
View attachment 220652
I went with with K8 heat sink with some .5mm thermal pad to make the connection
GCRC 'Maximus' (50mm) motor fan would not fit so cut the body for a cold-air-intake kind of thing
View attachment 220654
GCRC 'Typhoon' ESC fan required different screws than the MMX8S so used an M3 tap to get it together
View attachment 220656
Able to stuff Flysky FGr4 and castle bluetooth in the stock box.. barely
View attachment 220658
Phase 2 result:
View attachment 220659
View attachment 220660

Phase 3 will be mostly cosmetic/reliability and will begin when I have a significant breakage (already stockpiling parts 😏).

Overall very pleased with the build, averaging ~130 temps in 90+ ambient on 20/50 gearing and handles great. Full weight comes in at 15.4lbs. Only regret was not including ceramic bearings in phase 1; now am faced with the daunting task of tearing everything apart to mark project 'done'. Only other regret was not building sooner.
And for those interested here's my gearing on 6s with backflips. I haven't GPS'd it yet and I don't really care to, but I think the 46mph calculation below is very conservative.
View attachment 220666
Congrats! That's very cool!
 
Solid looking build man. 👍
Love your eye for organization, especially for screws placement -that outline of the chassis, smart!

*************

And, Welcome to the Ranch!
 
I'd imagine that castle combo doing more than 46 with 20/50
 
I'd imagine that castle combo doing more than 46 with 20/50
I believe it does. Take calculation with a grain of salt as I hacked to simulate real world; decreased lipo cells from 6 to 4, V/cell to 3.75, and did not account for tire balloon. When I get bored with it I’ll test ~24/46 but for the time being it’s an absolute riot to drive and has not left me wanting ‘more’ in any situation I’ve put it in.
 
Build Update: Long day at the workbench yesterday but rebuilt all three diffs adding M2C Outdrives, replaced all bearings with Avid ceramics, and swapped in M2C extended 17mm hex. I also tried to install RPM wing mount but couldn’t get it to fit, but I may have just been delirious as it was after 2am by that point.

Happy that I serviced as soon as car started acting funny, found that rear diff had no gasket from factory and was not surprisingly bone dry.

Went with 50k front, 200k center, 20k rear, and left the LSD in the stock configuration (min effect rear, max effect center and front) but would love feedback on this as I couldn’t find much intel or compelling arguments on ‘effect’ vs oil weight.
C510D708-C0AB-4C68-9256-CBDC405B9D47.jpeg


A690BE86-A6C5-4AA7-8D6A-E19003AC3861.jpeg


172E5A08-BD53-4817-ADC4-D8C2CBC98864.jpeg


8B3116FC-C540-4A47-85FC-901C5F07A1C9.jpeg


E3DEAD7B-D236-4E7F-A8DF-325343AADA6F.jpeg


F38E255A-9305-41F5-A086-385F47743D8B.jpeg

Also worth noting, I used these for the first time and they worked out great:

_degreasing wipes - useful for cleaning old grease off of diff and scooping out of bulkhead
_foam swabs - shred resistant and small enough to ’screw’ into M2 threads with break cleaner. Got awesome contact this way and will def use these for everything on the go forward.
 

Attachments

  • E1E1AF12-8E6F-4E9A-B3CF-A250D9B057C1.jpeg
    E1E1AF12-8E6F-4E9A-B3CF-A250D9B057C1.jpeg
    303.9 KB · Views: 56
Last edited:
Update: received skyrc gps today and took it out for a quick spin. Drove on sketch road (smooth & plenty straight but no curbs and lots of lamp posts) Below is pretty close to top speed but think it may have a little more to give.

Obvi a significant delta from my original calculation:
8E4B17FC-666F-445E-B01D-7C15739D6818.jpeg
E25A0A48-5AE0-426F-B0E7-E5A296811F8B.jpeg
 
Haha that's funny, I knew that site was accurate. I put in your info and got this.

SmartSelect_20220628-170724_Edge.jpg
 
Haha that's funny, I knew that site was accurate. I put in your info and got this.

View attachment 226404
Wow that apparently is more accurate. I like being able to save profiles so I just changed the LiPo cells and voltage to get the top speed to match in my app.

One unanticipated benefit of rebuilding diffs and adding ceramic bearings is that motor is running cooler; after those 4x speed passes and some light grass bashing my motor temp was ~20deg cooler than it normal. I’m going to step up from 20T to 22T tonight to and will compare calculations vs gps again to see if calculations are dialed.
7EFD1EED-99C6-427E-BAB3-1BAB2AEAB452.png
 
’m going to step up from 20T to 22T tonight to and will compare calculations vs gps again to see if calculations are dialed.Up
Change of gameplan; against better judgement I ordered aluminum bulkheads and F/R hubs.. going to get new weight before regearing.
 
Cleaned all my old bearings today, oddly satisfying process.. maybe because it brought me back to my old skateboarding days. Big win was finally getting my 5yo involved in an ‘assembly line’ process!

16AEBD39-6197-44C1-A644-7C59E25B907A.jpeg
86749095-6DCE-4FBB-8035-2FEC0CA20451.jpeg
 
First off, a big thank you to everyone on the form for sharing such great information and the mod's for maintaining a wealth of info - as a new builder I was able to get through entire build without having to ask any questions.

6sEXB / Castle 1717 1650kv / MMX8S / M2C / PPS / JBI / ALZA / GCRC

TLDR Pic:
View attachment 220634

The build in chronological order:
Planning
View attachment 220637
Phase 1 start
Roller arrived on mother's day, thanks FedEx :rolleyes:
View attachment 220632
Parts laid out for assembly
View attachment 220639
Was too excited to get started and forgot to take a 'before' pic
View attachment 220643
Fully broken down
View attachment 220645
PPS motor mount 🤤
View attachment 220646
Reassembly
View attachment 220648Phase 1 complete!
View attachment 220650

After several packs I identified the following items to correct in Phase 2:
1. My makeshift servo mount extension was twisting / not going to work long-term
2. Motor was quickly getting to ~165 temps even with 18/50 gearing and would need fans
3. Tires were good but not great
4. MMX8S fan already broke
5. Spektrum tx/receiver felt slow and was a pain to switch between cars (with and without gyro)
6. Lots of un-necessary wiring

Phase 2:
JBI mount was a pain to get in; even after prying it into place I found the stock screws were ~2mm too long and need to file them down as I didn't have any of correct size:
View attachment 220652
I went with with K8 heat sink with some .5mm thermal pad to make the connection
GCRC 'Maximus' (50mm) motor fan would not fit so cut the body for a cold-air-intake kind of thing
View attachment 220654
GCRC 'Typhoon' ESC fan required different screws than the MMX8S so used an M3 tap to get it together
View attachment 220656
Able to stuff Flysky FGr4 and castle bluetooth in the stock box.. barely
View attachment 220658
Phase 2 result:
View attachment 220659
View attachment 220660

Phase 3 will be mostly cosmetic/reliability and will begin when I have a significant breakage (already stockpiling parts 😏).

Overall very pleased with the build, averaging ~130 temps in 90+ ambient on 20/50 gearing and handles great. Full weight comes in at 15.4lbs. Only regret was not including ceramic bearings in phase 1; now am faced with the daunting task of tearing everything apart to mark project 'done'. Only other regret was not building sooner.
And for those interested here's my gearing on 6s with backflips. I haven't GPS'd it yet and I don't really care to, but I think the 46mph calculation below is very conservative.
View attachment 220666
What did you use to get these figures ?
Wow that apparently is more accurate. I like being able to save profiles so I just changed the LiPo cells and voltage to get the top speed to match in my app.

One unanticipated benefit of rebuilding diffs and adding ceramic bearings is that motor is running cooler; after those 4x speed passes and some light grass bashing my motor temp was ~20deg cooler than it normal. I’m going to step up from 20T to 22T tonight to and will compare calculations vs gps again to see if calculations are dialed.
View attachment 226530
What did you use to get these stats ?
 
Old Thread: Hello . There have been no replies in this thread for 90 days.
Content in this thread may no longer be relevant.
Perhaps it would be better to start a new thread instead.
Back
Top