R/C Tech Forums - Corally Kronos XTR Thread

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Corally Kronos XTR Thread

Hi! I may be a little late to the party, but my Corally Kronos XTR is on the way.

Here might be a really good place to discuss all things Kronos related - upgrades, fixes, hints & tips.

If you've been running one, please share your experiences here - what gear are you running? What electronics sets your rig apart from the crowd?

Discuss......

My Kronos XTR story starts here...
https://cimg4.ibsrv.net/gimg/www.rct...185a6f0e51.jpg
https://cimg8.ibsrv.net/gimg/www.rct...49db2ff2fa.jpg
https://cimg3.ibsrv.net/gimg/www.rct...efdc4721d5.jpg

Having read all sorts of stuff about issues with pivot balls and carriers, I was keen to see if they are the revised, stronger version or the ones that fall off. It's quite difficult to tell and I was looking for reinforcement webbing - but they look the same.

The body has clips and tethers pre-fitted. This surprised me as early reviewers complained that they had to fit them themselves.

Suspension is silky smooth, no rubbing of springs on shock bodies and no air in the shock oil.

Steering is super free and with zero slop.

Nothing looks cheap or poorly put together.

All that being said, I personally would still have preferred putting it together myself. I still need to choose my electronics etc, so it would not have bothered me spending a few hours building this car and getting to know it.

Make no mistake, whilst I find it quite difficult these days to get ultra excited about an RC car, this is a remarkable rig - it really is.

1/8th scale is a sweet spot size-wise for off road trucks and buggies. Large enough to run on un-prepared ground, but small enough to have low weight.

The Kronos XTR is certainly in that zone but it's bigger and heavier than my Xray XT8 at around 4000g. Considering the bracing and over-engineered everything,, it's still impressively light.

The chassis looks absolutely sub-zero cool. My first upgrades will be carbon parts for the A arms and steering plate.

Receiver is on the way. I'm still open minded about what Motor and ESC to use, but I'm very tempted to try the Kuros 185 motor and Corally ESC.

Obviously, if you guys here think that there are better combo's to be had, please feel free to point me in the right direction.

I'll take some more pictures tomorrow. But so far, I'm very impressed and can't wrap my head around such negativity towards this outstanding rig.

So, today I had time to take the body off and have a detailed look at the chassis. All seems way better than you'd typically find on a pre-asembled RC Car.

I was really impressed by the addition of an extra body - that's a really nice touch, along with a spare set of decals.

Instructions seem clear enough, printed in mono onto paper. It's not something I worry too much about these days as instructions are significantly better than they used to be. If you're looking for glossy, brochure-like instructions - these ain't that. But everything you need to know is there.

Size wise, wheelbase and arm length are quite similar to a race-oriented Truggy, only with significantly larger diameter wheels/tyres.

https://cimg5.ibsrv.net/gimg/www.rct...4d50f2e672.jpg
https://cimg6.ibsrv.net/gimg/www.rct...18d4e9204c.jpg
https://cimg8.ibsrv.net/gimg/www.rct...3fe9f9dd5d.jpg
Overall, the Kronos has at least an inch or so wider footprint than a typical truggy, with this extra width coming from the tyres rather than the actual track width.
https://cimg7.ibsrv.net/gimg/www.rct...298328fe56.jpg
https://cimg8.ibsrv.net/gimg/www.rct...ed5e8bf728.jpg
A 1/8th monster truck with 40 series is likely going to be wider however - as this Savage demonstrates.

So, the Kronos sits in a really nice zone somewhere between racing truggy and big 1/8th monster truck.

https://cimg5.ibsrv.net/gimg/www.rct...a91eed6438.jpg
With the shell off, the quality of this rig starts to shine. It's not your typical Basher Truck.

This is exactly why I chose it over an Kraton EXB. Don't get me wrong, if my trip down brushless lane goes well, I may be tempted to get one of those as well. But for now, I don't feel starting with this beast has been a bad idea at all.

https://cimg4.ibsrv.net/gimg/www.rct...22c03d3e27.jpg
https://cimg5.ibsrv.net/gimg/www.rct...32b5cb01a1.jpg
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I have no idea what spline count is on the alloy horn, but it's nice that they include one!

Motor mount looks really nice.

All the screws have tidy, countersunk washers for the countersunk, hi-tensile, steel screws. Nice.

The chassis is 3mm 7075. Now I suppose if you jump to the moon and lawn dart, it's going to fold in half. If you jump intelligently and set your shocks right - 3mm of 7075 should prove strong enough for most of us whilst remaining nice and light.

However - this is a rig that will typically have 4+ HP motor powering it, compared to a Nitro truggy that likely never see more than 3 HP. Food for thought.

https://cimg3.ibsrv.net/gimg/www.rct...c8046c7172.jpg
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Front and rear ends - anti-roll bar need slight adjustment to remove a little too much float, but really easily remedied.

Lower arms front and rear have the option for WCF inserts. By the looks of things, on the front arms, these can be placed both sides of the lower arms. That's a fair number of inserts.

Making the arms more rigid may help stop the arms bending past the point where they break, but on the other hand......lets just say that flexible arms are generally what you'd need if you're bashing and rigid, stiff arms are what you'd be shooting for if you're looking for consistent, precision handling - especially in hotter climates - where plastics can get a bit wibbley wobbly.

Camber on the front right wheel is positive - so this obviously needs some adjustment. Steering alignment seems good, with a hint of toe out, which is what I would usually start out with on a 4WD.

https://cimg6.ibsrv.net/gimg/www.rct...67a5a38256.jpg
Pre-painted body has a graffiti vibe going on...

The body has an over-spray film left on, so it's worth making a note of this before rushing to put the pre-cut decals on! :lol: I wonder how many people have put their decals straight on over it?

The front grill and light decal is large and doesn't really line up with the lines on the body, so I actually cut the lights off, fitted the grill first centrally, then placed the lights.

The smaller decals are easy for most people to apply, but the temptation with pre-cut ones is to just peel the larger decals off the backing sheet as well. Then optimistically attempting to line them up as you stick them, whilst day dreaming of blasting the rig around. Don't bother.

Cut the larger decals out of the sheet, peel one end of the decal, then roll the backing off as you apply it to the body. If you don't do this, between the static and all the other alignment issues, you'll end up with annoying bubbles that need prodding with a pin to remove.

https://cimg8.ibsrv.net/gimg/www.rct...66be0503c9.jpg
Decals on - this truck looks anarchic!

The dorsal fin is an acquired taste, it's certainly different - in fact it's quite reminiscent of the old F1 racing cars of the 50's. There's no way I'm going to say it's less attractive than Arrma offerings - it's just different. I suppose the dorsal provides yet another surface to mount decals for your faux sponsors! :sneaky:

https://cimg6.ibsrv.net/gimg/www.rct...1e9cdf9fc3.jpg

One minor criticism - my body was pre painted, but also pre-scratched! It's no biggie, but I'm out of fluorescent orange. :lol:

This Corally is a far cry from the Team Corally I knew growing up, with their 1/12th Circuit World Championships etc.

If anyone tries to tell you that this Truck is a direct rip of the Arrma, rest assured, it genuinely isn't.

The stand out for me is how silky smooth the whole driveline is. The gears are precision cut. XTR's are noticeably quieter than Kratons.

These trucks are great news - Arrma and Corally should form a 'special relationship' and stop certain other brands from monopolising the truck market.

One last thing - Corally. Their name is pronounced 'Cor'-'Alley'. Not 'Coe' 'Rally'. And definitely not 'Coral'-'Eee'. Please..... :sneaky:

For now, I've ordered Torox/Kuros 185 electronics. This motor esc combination is very rapid on 6S and smooth/controllable on 4S, so seems a logical place to start.

From what I gather, I can get a motor mount riser from Basherqueen if I want to experiment with 'big block' motors, negating any need to gouge or trim any of the side guard mounting screws.

It's far quieter here in relation to the Kronos than I was expecting, but I suppose RCTech is not the usual forum for bashers.

I'll keep updating this thread though. There are bound to be some other members that get one soon......

RC Guy Garage didn't have much luck with his.

However, I encouraged him to persevere. Amazingly he responded with this!

L
https://cimg5.ibsrv.net/gimg/www.rct...0bced669f2.jpg
https://cimg8.ibsrv.net/gimg/www.rct...de0f22ee60.jpg
Looks nice in both flavours IMO, but it's nice to have 1 that's different to the rest.

So, onto the electronics which are being fitted today.

I'm ordering a AGF-RC A81BHMW servo - I've seen no bad reports for these and whilst I've got a nice selection of Protek 170's in my other cars, I'm struggling to source them at a sensible price at this current time. I don't really feel like paying £170 or more.

https://cimg1.ibsrv.net/gimg/www.rct...01d5ae99cc.jpg

Picked up one of these 6S 60C Gens Ace Hard Case Lipos at a good price. Might get a couple of 4S as well for more sensible running.

https://cimg9.ibsrv.net/gimg/www.rct...68605a76b3.jpg

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Dual lock used for firm securing of ESC & Switch. I can literally pick the truck up by the ESC! So it's much better than velcro. The other nice thing is, you can pry them off without having to re-apply double sided tape all the time, which was one of things I hated with electric 1/10th.

I've used this stuff on the Drones as well and it's awesome. I'll always keep this stuff in my pit box.

I removed the battery holder and noticed the non-captive nut is also not a nyloc, which is a bit disappointing, so it's been replaced with one. The next very minor gripe is the lack of screw that holds the ESC mounting plate to the chassis. The counter sunk hole was there in the chassis, but the M3 screw had simply not been installed during the factory build.

Yet another example of why it's better to build these kind of cars yourself. There's simply no way somebody on a line can afford the same kind of loving attention to detail as we can.
https://cimg2.ibsrv.net/gimg/www.rct...24c6dc8e96.jpg
Things are much more likely to stay put now. I'm convinced that a 6S battery flapping about isn't a good idea. 🤣

https://cimg8.ibsrv.net/gimg/www.rct...7009fb7bc0.jpg
Gubbins installed - just waiting on Servo now.

So, the AGF-RC A81BHMW has been on my bench for a couple of days and Christmas holidays approach......

https://cimg8.ibsrv.net/gimg/www.rct...8acee41757.jpg
Neat packaging, rosey coloured display
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Nice alloy clamping horn provided
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Mounting grommets and nylon horns

It's looking like a very high value package with good specs. It's fine to run on 8.4v, so 45kg torque and 0.08/60° speed should be ample everything for a Truggy. Waterproof and also programmable (for those that feel the need to get geeky with their servos).

Let's see how it does......

So the AGF-RC A81BHMW was fitted with the anti-vibration grommets and installed into radio box.
https://cimg6.ibsrv.net/gimg/www.rct...f1f218081d.jpg

It seems there are a growing number of pros that dislike using grommets, stating that centering is negatively affected.

Personally, I find if the grommets are well fitted and tightened down just right, there's no perceptible centering issues at all.

You'll see people discuss this and many claim that modern servo's IC boards and electronics are much less prone to vibration issues - though nobody appears in a hurry to actually explain how.

In my estimation, they still have boards with tiny components soldered on to them in exactly the same way as before.

I also read plenty of online stuff where people complain about manufacturers NOT replacing servos that have failed. Go figure.

Having bound my Futaba 3VCS to the FrSky 4ch FASST receiver, I was ready to set endpoints on the servo and calibrate the ESC. Note: binding the receiver seemed not to be working at first - but this was because my transmitter was on a new model setup with 'PCM' modulation as default. This was set to HRS and it was then ready to bind.

https://cimg5.ibsrv.net/gimg/www.rct...fe8e4e4091.jpg

According to the Corally ESC instructions, Futaba radios need to have their throttle channel set to 'Rev', so I that's what I did.

With the 6S Gens Ace 60C 4800 lipo hooked up, I set the throttle neutral, full and brake points.

To my utter astonishment, it all works flawlessly first time and the servo is super smooth, accurate, fast and near silent. Very impressed!

The red alloy horn supplied wasn't appearing to fit the splines on my servo very well, so I used the nice clamping horn supplied with the AGF-RC 81BMHW..

Well today, I have concluded that all my years racing and tinkering with RC cars has brought me to the exact right spot.

I haven't rushed into everything or bought loads of stuff that I didn't really like, but on the other hand, I haven't really been static either or limited myself to just one niche.

Imagine my surprise when, after running my Kronos XTR for the first time, I realised that brushless is everything I liked about my 1/10th electric and 1/8th IC Buggys all rolled into a big, bad, insane Truggy. If the Xray XT8 was a scalpel, the Kronos XTR would be a chainsaw.

It's literally awesome. I haven't had this much fun since I waited for the overnight charge of my Tamiya 7.2v hump pack to finish up so I could go blast my Sand Scorcher around the Alleys!

In fairness, it sounds smooth and uneventful but it belies a machine that is bonkers in every way. 6S is OTT but fun. On 4S it would probably still be far from sensible, but less stressful!

Amazingly, it's still all in one piece and hasn't been scuffed up yet. Wheelies occur just by looking at the throttle. I'd hate it to get road rash, but it's going to happen....

https://cimg3.ibsrv.net/gimg/www.rct...43688ffc2e.jpg