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-   -   XPRESS Dragnalo DR1S (https://www.rctech.net/forum/electric-road/1089711-xpress-dragnalo-dr1s.html)

Airwave 09-16-2021 03:57 PM

XPRESS Dragnalo DR1S
 
https://scontent.feml1-1.fna.fbcdn.n...30&oe=6167A55A

Officially announced some days ago : https://www.redrc.net/2021/09/xpress...c/#more-200869
Official page : https://www.rc-xpress.com/-00109371

https://www.redrc.net/wp-content/upl...ressDR1S-1.jpg


Xpress Dragnalo DR1S was designed to handle power thrown at it much higher than the traditional 2s LiPo and 540 sized motors. From Circuit racing to Drag racing and 2s lipo to 6s lipo, the drivetrain was designed to deal with all of these high powered systems with your choice of 540 or 1/8 scale application motors!
What guys do you think about that?

Airwave 09-16-2021 04:02 PM

Should I post my own word on it first...
I own a Serpent 748e for a long time and it is mainly the same target. But when Serpent built this car it uses a Nitro car as model, so bearing, dogbones, belts, differentials and even upper and lower arms are tough. It has no problem to endure 4.5T with 2S or 3652 motors with 3S. I've made a lot of tries and it is always the electronics which gives up.
Here Xpress proposes a car derived from XQ2S, mainly in plastic, with traditional transmission but a 6mm belt in the rear. I've read about speed records chase, it could be good for that, but for anything with a more violent acceleration (such as track racing or drag racing), I'm not confident it will hold...

performula 09-16-2021 04:09 PM


Originally Posted by Airwave (Post 15824849)
Should I post my own word on it first...
I own a Serpent 748e for a long time and it is mainly the same target. But when Serpent built this car it uses a Nitro car as model, so bearing, dogbones, belts, differentials and even upper and lower arms are tough. It has no problem to endure 4.5T with 2S or 3652 motors with 3S. I've made a lot of tries and it is always the electronics which gives up.
Here Xpress proposes a car derived from XQ2S, mainly in plastic, with traditional transmission but a 6mm belt in the rear. I've read about speed records chase, it could be good for that, but for anything with a more violent acceleration (such as track racing or drag racing), I'm not confident it will hold...

All the 200mm cars are tanks.

Airwave 09-16-2021 04:14 PM

Not really, take a look at Arc R11W. It was also designed for foam tyres and lola body, keeping the 2s limit.
But I agree, Serpent 748e and even 750e are heavy (about 1.5kg RTR)

gigaplex 09-16-2021 04:31 PM

I've been doing Velodrome speed runs with my FT1S with a 4.5T on 2S. The suspension, diff, driveshafts all hold up fine. The weak point is the single 3mm belt which I strip somewhat frequently.

Being 4WD to spread the load and with a chunky rear belt, this thing should be able to handle a lot of power.

Airwave 09-16-2021 04:57 PM

I suppose that you have a HUGE pinion to ensure top speed. That's not what I would call a violent acceleration (as it does not matter, top speed is the target)

gigaplex 09-16-2021 07:55 PM


Originally Posted by Airwave (Post 15824869)
I suppose that you have a HUGE pinion to ensure top speed. That's not what I would call a violent acceleration (as it does not matter, top speed is the target)

35T pinion. The drivetrain experiences a ton of stress in the corners, and if I hit a bump it gets airborne and the landing will shock it too.

I also clipped the wall at over 100km/h once. Snapped a knuckle and C hub, no damage to the axle, diff or arm.

Hannes 09-17-2021 02:47 AM


Originally Posted by gigaplex (Post 15824863)
I've been doing Velodrome speed runs with my FT1S with a 4.5T on 2S. The suspension, diff, driveshafts all hold up fine. The weak point is the single 3mm belt which I strip somewhat frequently.

Being 4WD to spread the load and with a chunky rear belt, this thing should be able to handle a lot of power.

I don't think you can compare a FWD car to a 4WD with possibly foam rubber tires in terms of forces acting. Using a wider belt in the rear was definitely a good idea. Leaving the standard 3mm belt in the front was less so in my opinion. For the XQ10 there is not without reason 4mm wide reinforced belts.
The concept itself I find good, but in the drivetrain I see some problems if the vehicle is really driven with foam rubber tires and 3S or more.

As said already, for speedruns it might be good, but as soon as hight traction and hard acceleration steps in the game, it might become a very cost intensive and frustrating thing...

gigaplex 09-17-2021 07:48 AM


Originally Posted by Hannes (Post 15824963)
I don't think you can compare a FWD car to a 4WD with possibly foam rubber tires in terms of forces acting. Using a wider belt in the rear was definitely a good idea. Leaving the standard 3mm belt in the front was less so in my opinion. For the XQ10 there is not without reason 4mm wide reinforced belts.
The concept itself I find good, but in the drivetrain I see some problems if the vehicle is really driven with foam rubber tires and 3S or more.

As said already, for speedruns it might be good, but as soon as hight traction and hard acceleration steps in the game, it might become a very cost intensive and frustrating thing...

My FWD has foams. My point was that if most of those components are fine in 2WD where all the force is on the single diff/axle pair, it's probably fine in 4WD where the load is shared. Velodrome runs aren't the same thing as a straight line speed run. They're constantly accelerating hard when cornering.

FWIW I also have the 4mm belts for my XQ10. I just wish they had them for the FT1S too.

Airwave 09-17-2021 03:23 PM

Pretty sure taht it would be fine for speed runs, straight or in a velodrome. What I find strange is that it seems that they are targeting drag race (the rear wheel and the front weight under the foam), but I'm not sure there is a such category in drag races now...
I can only agree with Hannes about foam. A car designed for rubber tyres will never get the same efficiency with foam than a can designed for foam. My serpent 748, for instance, is just undrivable with rubber tyres. You can just take a look under the chassis and you will see that the geometry is very different.
https://lh3.googleusercontent.com/pr...jvu1acPqfVTRGk
By the way I'm not sure it will stop me from getting one lol

1/8 IC Fan 09-21-2021 04:10 PM

No thanks, i'll pass... they could häve done much more to make it a better car. All that Plastic and (I assume) G-10 is just gonna keep people buying spares / upgrades. I thought at first a dedicated 200mm car like you said the 748... which given noise restrictions at the Track, would have made a great alternative.

Airwave 09-22-2021 03:05 PM

You should go for 748e before it is gone and 750e (also a disappointment for me) is all what's left...

performula 09-22-2021 03:43 PM


Originally Posted by Airwave;[url=tel:15826760
15826760[/url]]You should go for 748e before it is gone and 750e (also a disappointment for me) is all what's left...

They are both bad? I was on a 200mm kick back in 2016 coming from nitro. I had the 748e but sold it nib.

Airwave 09-26-2021 02:51 PM

From my POV, 748e is one of the best 200mm foam touring car you can drive on a track. It is agile with 4.5T in 2S but it is a missile when it comes to 3625 motor in 3S. It could be really really fast, even faster than the 748 nitro itself. The car has been built like a touring car, but with nitro geometry, so that the best of both world.
Now consider that this is not even a category. Nobody is racing 200mm foam electric cars. You can find only a few alternatives... So Serpent decided that the next car will be designed to be used in a growing category: drag racing and speed racing. So they took the nitro chassis, just put additional carbon wings to fix the batteries and add a wheelie bar... You got it. The car is heavier, less agile, and mass repartition is absurd for track racing. I've adapted some of the new parts to my 748e (like carbon arms or magnesium transmission), but I'm still convinced that the 748e is way more adapted to track than the 750e. Look how fast it could be compared to a 988e :

Sorry back to the topic...

auto2 10-17-2022 06:29 AM

Drag racing dr1s
 
I've been testing this car and it's really good. Anyone want to share info?


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