Kraton Questions on shimming the diffs

[Nuanda1978]

Dear All,
i'm in love with my V3 Kraton and in upgrade-mania.

With the servo upgrade under my belt, i'm now looking at shimming the diffs as i'd like to make the leap to 6s batteries (i'm on 4s at the moment) and i do want to reduce as much as possible potential damages.

I have looked at all the various threads and vids, but i still have some basic doubts (i'm 100% inexperienced):

1) If shimming the differentials is a no-brainer way to bullet proof them, then why on earth don't they come pre-shimmed?

2) As i do think if i try to shimm my diffs there's a great chance i won't be able to do it and end up with a broken unusable diff, i'm seriously considering to buy a full spare diff to "practice" and eventually put in my Kraton (yes it's a waste of money, but it's an hobby...i will likely spend hours assembling the 50$ spare diff. Better that than beers). Now,
- Am i correct in saying that shimming the center diff is the most important one vs. shimming all 3?
- Are the 3 diffs the same part number AR22029? https://www.arrma-rc.com/part/AR220029

3) What scares me is that shimming might not be a 100% defined procedure, but rather that each diff might require a slightly different shimming (which would answer question number 1)...in this case, i'm afraid i just won't have the experience and talent to understand how my particular diff should be shimmed (i need a one-way procedure that tells me "put part A into part B etc.", not "put part A IF...".).

Other than this, i just want to tell the world that i felt like a kid again playing with this thing!

 

[Trapper]

It's not a bad thing to have an extra diff because gears wear out after some time so they will get used eventually. Some parts when made vary ever so slightly is why the shimming helps and likely a reason why they don't bother shimming because it takes time and time is money... My theory on that at least. Some have the opinion that you need to shim the diff to where all gears are jammed up super tight together to the point of them resistant to movement because eventually they will make a wear pattern and loosen up naturally from wear and tear while others prefer to have their diffs shimmed up to where the gears mesh well and have a solid buttery smoothness to them. Enough to remove the slop or play but not enough to resist movement.

 

[RCROD]

Dear All,
i'm in love with my V3 Kraton and in upgrade-mania.

With the servo upgrade under my belt, i'm now looking at shimming the diffs as i'd like to make the leap to 6s batteries (i'm on 4s at the moment) and i do want to reduce as much as possible potential damages.

I have looked at all the various threads and vids, but i still have some basic doubts (i'm 100% inexperienced):

1) If shimming the differentials is a no-brainer way to bullet proof them, then why on earth don't they come pre-shimmed?

2) As i do think if i try to shimm my diffs there's a great chance i won't be able to do it and end up with a broken unusable diff, i'm seriously considering to buy a full spare diff to "practice" and eventually put in my Kraton (yes it's a waste of money, but it's an hobby...i will likely spend hours assembling the 50$ spare diff. Better that than beers). Now,
- Am i correct in saying that shimming the center diff is the most important one vs. shimming all 3?
- Are the 3 diffs the same part number AR22029? https://www.arrma-rc.com/part/AR220029

3) What scares me is that shimming might not be a 100% defined procedure, but rather that each diff might require a slightly different shimming (which would answer question number 1)...in this case, i'm afraid i just won't have the experience and talent to understand how my particular diff should be shimmed (i need a one-way procedure that tells me "put part A into part B etc.", not "put part A IF...".).

Other than this, i just want to tell the world that i felt like a kid again playing with this thing!

I just ordered a new Talion before XMAS & it never showed up, lost in limbo somewhere? I then decided to really jump on the bandwagon & not just reorder my new Talion (my 1st Arrma vehicle), but also get a new Kraton (I watched too many Aarma videos I guess...) The hobby store had a couple Kraton's in another warehouse, so only had to wait 2-3 days. I then mistakenly decided to make some small changes to my order (add a few items) before they sent everything out, & damn, I lost the Talion to a Gold member who had a Talion on backorder. Living in Canada, I obviously don't want to split up my order, as this would greatly increase the shipping & import charges, but I didn't want to wait for the Talion either (they said could be 1 month wait now as big backorder?). The hobby store solved everything for me & sent out my RC order with the new Kraton on Monday. Now I don't have to hold my order for the Talion, as they gave me free shipping + no customs on 2nd order. Finally, I will have an Arrma RC (2018 Kraton) in my hands, in hopefully less than a week.

From what I have been reading, it looks like the shims needed for Aarma diffs are 3.5x12mm, 5x18mm & 13x16mm. It looks like many of Arrma users have shimmed their diffs (check videos) using the Mugen diff shim/washer set (MUGE0206), 3.5x12mm (0.02mm thick) & 5x18 (.2mm thick), but it is sold out (+ I was advised by big hobby store this has been on backorder for over a month?) Arrma does offer the small washers 3.5x12x.15mm (ARA709024), but also sold out. I'm not sure if that is a misprint on Tower Hobbies website showing the Mugen 3.5x12mm shim only 0.02mm thick, and should be .2mm?

I did find an Associated diff shim set (#81381) & good news, someone left a review saying these are an excellent fit for the Arrma Kraton. This shim set includes:
3.5 x 12 x 0.12mm Shims
6 x 8 x 0.20mm Outdrive Shims
13.5 x 15.8 x 0.20mm Shims
13.5 x 15.8 x 0.10mm Shims

I guess the 13.5x15.8mm shims are close enough to 13x16 shims everyone had been using?

I ended up getting the Associated 8131 shim set, and since I will have 6 diffs to possibly shim, I also got Serpent 3.5x12x.2mm shim set (SER110413). This gives me 2 options for the small shims (.12mm & .2mm thick). Maybe we can use one .12mm shim on each side instead of using 1 larger shim on only the one side, that it looked like everyone had been doing?) Xray also has a 3.5x12mm shim set.

I also bought Kyosho 13x16x.15mm diff shim set (KYO96772), so now I will have 3 options for the large shim (.1, .15, & .2mm), so should be able to shim the diffs up really well. Many other choices for 13x16 shims, (all ranging from .1-.2mm), including; Tekno, Protek, XRay, HPI, Sworks, Serpent.

I cannot find 5x18mm shims? Only choice is Mugen 5x18x.2mm, since Team Durango 5x18x.1mm now available? CAN ANYONE PLEASE ADVISE HOW IMPORTANT ARE THESE SHIMS OR SHOULD I WAIT TO SHIM MY DIFFS UNTIL 5X18MM SHIMS ARE AVAILABLE?

I shimmed once before with a truggy kit. I agree with Trapper, take as much play out as possible, with everything as free as possible to still move smoothly. I'm hoping this will not be too difficult, just not sure about the 5x18 shims if needed & even available anymore?

 

[ASenton]

I have never shimmed anything on my typhon 6s upgraded motor and esc in 8 months and still going fine

 

[Boostedpig]

Not landing under throttle and using punch control to roll on the power vs all at once will help prolong the life of the diffs. Also the lighter the truck the easier it is on the drivetrain plus 4s vs 6s makes a big difference.

 

[TpPartsRcXtreme]

I have never shimmed anything on my typhon 6s upgraded motor and esc in 8 months and still going fine

Does not mean anything sir. Every single rc car, kit or RTR, should be looked over. For the cars sake, open up them, ad the 18x5x0.2, and ev outer to adjust crown/diff pinion mesh.. just a tip buddy..i still run 3 years old diffs due to the shiming none broken so far. ☺

 

[Parker]

which savox servo can I use with out any mods in my nortorious or do all of them require modification with spacers. I was going use a1210 sg for high torque but I think i have to use spacers does anyone know. THANKS

 

[PowerDubs]

Why is this posted in a shim thread?

I know either of the monster savox servo will fit with no mods at all. I recently put the speed one in my Notorious.