Paul Busby

My guess, given a bit of on the sofa google-fu, I'm having a hard time finding the stock wheels, or even a great deal of choice in 1/8 on road wheels, is that they're some random eBay specials, and not the same size as stock. I know the dBoots hoons are 1/7, technically, but maybe they would be an option? (100mm) GRP do a 1/8 do a range of "on road" wheel that might be worth a look. (~98mm) Sweep also do some. (~108mm OD) What's the OD for the ones you have currently?

It's included with the Kraton, yeah. You can always loosly put it on, then if it doesnt fit, just stick with the 18T.... just be prepared for that first throttle blip. Will be a hooligan.

Looks good to me. I'd still recomend putting the 15T speed pinion on for your first drive before jumping up to 18T My only suggestion, and this is completely optional, is to also get some heavier oils, especially if you want to run it in the winter in the mud and such. Stock oil is fine, but most people (myself included) find that the truck responds well to thicker oil all around. It can really help with tyre balooning when giving it the beans on the ground. 300-500k centre, 20k rear, 40k front... something like that. It's one of those things that's very much a personal preference though, I've gone up and down in weight a lot and find this to be the sweet spot.

Here is the most recent desgin ...sorry the photo is a bit rough, it's the best one I can find on hand. I also wouldn tuse this plastic with the pattern again, it didnt hold up well in testing. Below that is the older design. Note that these were all made basically in my garden with a Dremel and a Scrollsaw. I have all manner of tooling now. I'm going to start making some templates after christmas. Already got a bit of plastic stock. I'm going to experiment with a mix of Nylon, Nylatron, and UHMWPE. The PE varient being nearly indestructable and abrasion resistant, and the Nylon/Nylatron being a bit more rigid/sturdy.

I've already got a couple of designs mate, but if you have something you would like to see feel free to let me know. [emoji106]

The drive train loss is an arbitrary number I used to calibrate against the online calculator I found 😄 You should be able to download it and check my workings though.

Added to my spreadsheet. Appears you have spotted another clanger, and I was actually using copperhead 1

165mm (Copperhead 2 6s). Have a look at my spreadsheet mate, it's pretty handy 18T gears you for 59.27MPH, so a bit slower than the speed pinion with a stock Spektrum motor

No it's identical... but you're right. I'm getting my "real speeds" and "gearing speeds" muddled up. I'm curious, are you using an online calculator, because my spreadsheet has 20t @ 22.2v @ 65.85MPH "gearing speed". TBH if you stick the speed pinion on it that came in the box, that gives you a good starting point, then you can go up a few teeth if you feel you need more (I reckon you will).

These are also the best pinions I have used: https://www.rwracing.co.uk/product/cnc-1-module-steel-pinions-5mm-bore Tekno ones are equally as good. Nothing really wrong with Arrma pinions tbf.

Aye, that's the number.

Exactly. Get a 20t to get the overall speed similar to a stock Kraton (50-60mph)

While we are on the topic of bumpers, I will mention that my workshop is in a state that I can make stuff now (do need to update the build thread), so I can (and would really like) to make bumpers for people again.

I know, I was just poking the bear 😜 I've actually started backing off on some the upgrades and going back to stock in some areas. Is it still the Vitavon diff cases that you would go for?

I have a big, enclosed printer that can do fancy filaments, also got a good stock of filaments, so I'm open to printing stuff off if the need arises. Just let me know [emoji6]

You have a Max6 so you should be good with the extra weight [emoji16]

Probably wouldnt be sufficient saveing to be worth while when it's an entire body, also not exactly practical to 3D print, but I can do some bits out of carbon fibre nylon which should be about 20-30% lighter. I also still don't have my CNC up and running Should be early next year I get to that stage, might even have a new one if they sort this bloody brexit trade deal out.

Yeah you can cut the wing mount short and do that, but it all depends on where it breaks as to whether you would need a new one or not due to how many parts of the truck it connects together. If you take a peek, you can see it's one of parts responsible for holding the rear brace to gearbox, as well as holding the wing on the car. Easy enough to fab something up to delete it of course. With the gearbox, It's not so much that it's a weak spot, it's just that the spares all seems to be warped/poor manufacturing tolerances, so you have to stretch/fettle them back into place. Part number (AR310854) hasn't changed, so if they've sorted that issue or not, they haven't significantly changed the design. I was lucky in my last swap I did, the replacement I ordered was old stock (could tell by the different card label on the bag) and that went in like a dream, perfect fit.

My only recommendation of spares to have on hand is the wing mount (that also connects to the gearbox and rear brace). Blows me away that they haven't designed anything around that to make it a bit tougher, suppose it's a deliberate weak point? Either way, they break really easily. RPM do one, which I haven't tried, it's in a box waiting. POS also do one which is awesome, but expensive. I have this one and it's why I haven't fitted the RPM one, it's super tough.

What is it about portals that takes away from your enjoyment? I ask because Im thinking about getting a crawler or two (kids don't seem to be gelling with bashers) and it seems portals are generally held to high esteem.

What filament were you printing with mate?

Posted my comments previously (quoted below). Bear in mind that the EXB doesn't do anything particularly special that a Kraton didn't do before, Arrma largely just included the parts that most folk have been adding to them for years. There is slightly different geometry on the suspension, slightly modified A Arms, and LSD diffs... I can't say how much difference they make (yet) but that's it, for all intents and purposes it's the same car with the same driving experience, just tougher. I'd probably argue my Titanium upgrades do a better job than the EXB ones, but that's up for debate. Thinking about it again, I also think my feelings on the MT410 might be skewed by the fact I have a sensored electronics set up... Which does suit the platform for sure. In terms of building, I've made no secret of my love for the Tekno build experience, and utter distain of the Arrma QC for spares (the gearbox replacements are utter turd), but I can guarantee you will have the Arrma in pieces and rebuilt from a bag of screws and plastic at some point [emoji6]

One thing I have seen a lot of people do is re-inforce bodies with drywall tape and a sort of contact adhesive. Seems to work well, even if it does add a bit of weight.

Exactly what I said before I bought my Max 8 [emoji2371]

Yeah I think you're right actually, it is a 12T. Not sure why I had 13T in my head. The EXB drivetrain is the same as the RTR trucks, with the exception of the LSD diffs. I wasn't suggesting that you cant run the Max 8, like I said, It's "ok". I also said, "it will do the job". I just don't know many people who have bought and installed that combo and not ended up changing it out for a Max 6, myself included (although my reasons were different). You go to the Arrma forum and most of the recomendations are for the Max 6, with quite a few people reporting temp issues with the Max 8 combo. My advice was from that of someone who has been running a Kraton for over a year now. If I was buying the EXB today, I would get the Max 6. I'm not saying "you must do this", and I'm not spouting out fanboy garbage, I'm just putting my 2c out there from my own experience, and that of people running similar rigs. The thing with the soldering is that it's actually not just soldering wires, something which is not an issue for most modestly experienced hobbyists, the issue is that its solding small gauge cable onto the middle of heavy cables that are fixed into the ESC. It's an unpleasant job to get right, even for someone who is experienced at soldering, which I am. Again, it's something that, from my experience, I think it's prudent to highlight to any prospective buyer so they can make an informed decision.