Kronos XTR Horatio's XTR Build

[Horatio]

The Front centre titanium driveshaft fits my 0° kick-up chassis perfectly. It's exactly the same size between the pins as my current steel driveshaft. Just as well, because on my rig, the centre diff has moved forwards thus the pins are at the furthest point inside the cups.

Being thicker driveshafts, means they cannot be angled very much at all and this means tricky center diff removal - even on my chassis without the bracing.

So before I install them, I'm going to see if there's anything I can come up with to enable less laborious centre diff maintenance.

Although much thicker, because they are titanium, they're a similar weight to the mild steel items - but obviously far less prone to bending. This should improve the efficiency of the drivetrain.

The carbon arm stiffeners arrived from Belgium - along with a big packet of Cola Bottle Sweets.

The Kagama front arms can be used either side as they are reversible ie they can be flipped over. This meant that the carbon fibre inserts can be added to both sides of the arm and held in place with M3 bolts and locknuts. Clearance is minimal, so I may replace the nylocs with flat M3 nuts instead.

Either way - upper Kagama arms are monocoque and very stiff with carbon inserts top and bottom. Obviously - just don't crash!

Speed runs to follow very shortly.

 

[Mark383]

Great tips, thank you. I'm going to order some Tekno M1's then. Makes sense to me.

I degrease my bolts and grub screws prior to applying blue loctite, but here the issue is just the way the thread lock has got it's panties into a wad.

I'll have a look for some fresh grub screws. I don't have a small enough tap, so nice clean grub screws should do the job. The thread in the pinion is ok. It's just weird how the the thread lock stayed on the upper portion of the threads and made a hat.

The grub screw on this pinion is about as big as it could be given the design of it - presumably the Tekno one have a little extra meat to work with? Either way, I'm sold on the larger grub screw. Cheers!

Hi Mate, +1 for the TEKNO's . I've never had one TEKNO pinion come loose since getting back in to the Hobby 6 years ago and I have them on all 5 of my rigs, Love their larger grub screw.. One thing is I always wipe the threads with a soft rag with alcohol on it to clean off the machining oil and I also always leave them at least 24hrs before use after installation to allow the LT to set.

 

[Horatio]

Will you still need me - when I'm 64?

So I finally had the chance to run my rig down the 1/4 mile strip.

The Louise tyres were excellent and afforded good levels of traction. Like the Sweeps, being lighter, the truck feels responsive and agile.

However, my pack was charged the night before and conditions overnight were frosty - so prior to the run, the cells had been cooled to about 10°.

Every run was 64 mph. Each direction. Motor barely got warm in the 13° temperature. The tyres being 145mm reduced the rollout.

But 17/46 should be good for more than 64mph - just not when it's cold.

Video to be uploaded soon.

As for the steering - all fixed. Straight line stability was excellent. The tyres progressively let go as they exceed the limit, making the car predictable as it loses traction. This equates to a car that encourages you to push past the limits.

Anyone driving these rigs on hard surfaces knows how challenging it can be to corner tightly, get the power down and circulate fast. This rig can do that.

Now I need to see what it's like off-road......

 

[Horatio]

Just picked this up!

 

[Niekname]

Nice! Do you have something in mind for it?

 

[Horatio]

Nice! Do you have something in mind for it?

Maybe..... I just liked the colour....

 

[Horatio]

And green might be faster?

 

[Sandracer_NL]

And green might be faster?

A lower profile body .

 

[samo975]

And green might be faster?
View attachment 7254

Green does mean “GO”

 

[Horatio]

Look at that beautiful colour!

The Scorched Parts 168mm limitless driveshaft fits perfectly in my rig.

Vs

Whilst the rear driveshaft is 8g heavier, it's proper sturdy and perfectly straight - zero wobble. They fit the input/output drives perfectly no problem. Having measured the ball ends, they are 7.8mm.

Fuel tubing cut to size centres the 168mm shaft. Approximately 3.5mm of silicone fuel either end and the job's a goodun'.

 

[Nelson.81]

View attachment 7260
Look at that beautiful colour!

The Scorched Parts 168mm limitless driveshaft fits perfectly in my rig.

View attachment 7276
Vs
View attachment 7277

Whilst the rear driveshaft is 8g heavier, it's proper sturdy and perfectly straight - zero wobble. They fit the input/output drives perfectly no problem. Having measured the ball ends, they are 7.8mm.

Fuel tubing cut to size centres the 168mm shaft. Approximately 3.5mm of silicone fuel either end and the job's a goodun'.

I guess you’ve added a little bit of heat to yours, nice touch, scorched shaft just 1 pieces engineering/machine work just feel the quality. I wondered if mine would change from heat in the driveline but obviously not getting that hot but the cups do get proper hot sometimes. I was looking at the tworks shaft & noticed the sworkz s35 is 88mm, not sure if s35t2e the same but maybe the scorched 85mm front shaft would work in it & maybe the scorched 83mm might fit your Kronos better but 83mm thicker @7mm.

 

[Horatio]

I guess you’ve added a little bit of heat to yours, nice touch, scorched shaft just 1 pieces engineering/machine work just feel the quality. I wondered if mine would change from heat in the driveline but obviously not getting that hot but the cups do get proper hot sometimes. I was looking at the tworks shaft & noticed the sworkz s35 is 88mm, not sure if s35t2e the same but maybe the scorched 85mm front shaft would work in it & maybe the scorched 83mm might fit your Kronos better but 83mm thicker @7mm.

The shaft naturally has rainbows when it catches the light right.

Muraco body looks good to be fair. Not bad for £30ish - although it's missing the roof skids that were in the listing. I checked the box thoroughly - they ain't there. Oh well.

 

[Horatio]

I've been having an issue with this M5 thread. Time to get it sorted.

19/46 gearing next.

On 140mm tyres, that gives an overall mm/rev of 54.93.

That's 81 mph on 6S theoretically. Making allowances for loss and a little voltage sag, I should still be good for 75 mph.

I now need to add extra rows on my system, because 19 is the maximum size I had for the XTR!

 

[Horatio]

Today's hooning around on 19/46 has taught me one thing: don't expect to necessarily attain higher speeds simply by increasing the pinion size, if you're trying to draw amps that you just don't have.

Sure, I was getting 66mph every run, but pinning the throttle to the max would see the Torox cutting until I let back off.

Hooning around and cornering at high-speed is absolutely on point with this rig, but 69mph is not going to be beaten in 10° temperatures.

The car is generating enough traction and is stable enough to hold full throttle in the dry, but my feeling is that whilst the chassis has more potential now, I have to get a more powerful ESC and motor if I'm to see higher top speeds.

I still think that for stock Torox 185 ESC and a cheapy eBay motor (Surpass 1780kv 4292) I'm doing ok - but I'm out trying to get anything better with this current arrangement. I'm drawing a line under 69 mph.

Would my Kuron 825 be faster? Probably. Would it pull 19/46 without going thermal? Doubtful.

So, Castle 1721? £289 motor.

What ESC do you guys think I should run?

 

[Horatio]

On a less techy note, the new Muraco body was good, handled well although I note that it's not as deep at the sides as the Kronos. The body looks like the mounts need to be lowered.

The truck itself ran flawlessly, hitting 66 mph each way, over and over like it was nothing. The new Scorched rear centre drive shaft did it's thing. Whisper quiet transmission.

Temperatures during the straight line passes on 19/46 were just 80°F. On the hooning around, sliding and cornering etc, the temps got up to around 151°F which is where I start to think about leaving it cool off.

Batteries held up fine, were hand warm at around 80°F when I finished. 1st battery seems to have really good punch and had 30% left in it when I stopped. 2nd battery was being run on a warmer motor and also hit 66 mph.

For those wanting a useable, with plenty of mid-range power type motor, the 1780 really can't be beaten and it's less than £50. It keeps it's cool on sensible gearing and is more confidence inspiring than the Kuron 825 when you pull gearing higher than 13/52.

However, for breaking 70mph - it's time for an upgrade....

 

[Sandracer_NL]

View attachment 7292
View attachment 7293
Today's hooning around on 19/46 has taught me one thing: don't expect to necessarily attain higher speeds simply by increasing the pinion size, if you're trying to draw amps that you just don't have.

Sure, I was getting 66mph every run, but pinning the throttle to the max would see the Torox cutting until I let back off.

Hooning around and cornering at high-speed is absolutely on point with this rig, but 69mph is not going to be beaten in 10° temperatures.

The car is generating enough traction and is stable enough to hold full throttle in the dry, but my feeling is that whilst the chassis has more potential now, I have to get a more powerful ESC and motor if I'm to see higher top speeds.

I still think that for stock Torox 185 ESC and a cheapy eBay motor (Surpass 1780kv 4292) I'm doing ok - but I'm out trying to get anything better with this current arrangement. I'm drawing a line under 69 mph.

Would my Kuron 825 be faster? Probably. Would it pull 19/46 without going thermal? Doubtful.

So, Castle 1721? £289 motor.

What ESC do you guys think I should run?

If you are planning make it a speedrunner go Castle (no amp limit on esc, but can result in if you push it too far.
If you also will bash it go Hobbywing. Max6 G2 has 200A and should allow you to get more out of the 4292.

 

[Nelson.81]

View attachment 7292
View attachment 7293
Today's hooning around on 19/46 has taught me one thing: don't expect to necessarily attain higher speeds simply by increasing the pinion size, if you're trying to draw amps that you just don't have.

Sure, I was getting 66mph every run, but pinning the throttle to the max would see the Torox cutting until I let back off.

Hooning around and cornering at high-speed is absolutely on point with this rig, but 69mph is not going to be beaten in 10° temperatures.

The car is generating enough traction and is stable enough to hold full throttle in the dry, but my feeling is that whilst the chassis has more potential now, I have to get a more powerful ESC and motor if I'm to see higher top speeds.

I still think that for stock Torox 185 ESC and a cheapy eBay motor (Surpass 1780kv 4292) I'm doing ok - but I'm out trying to get anything better with this current arrangement. I'm drawing a line under 69 mph.

Would my Kuron 825 be faster? Probably. Would it pull 19/46 without going thermal? Doubtful.

So, Castle 1721? £289 motor.

What ESC do you guys think I should run?

@£289 someone is pulling your pants down a lot cheaper @https://www.perfectpassrc.com/

 

[Horatio]

@£289 someone is pulling your pants down a lot cheaper @https://www.perfectpassrc.com/

Perfect pass does look like a much better price provided the shipping and taxes are sensible.

 

[Nelson.81]

Perfect pass does look like a much better price provided the shipping and taxes are sensible.

Shipping is expensive @ +£30 no taxes to be added that I saw still works out a fair bit cheaper than anywhere else I’ve seen.

 

[Horatio]