Truckifying a dragon?

[BuggyDad]

Thinking a bit further on this Saint Dragon deal:

https://www.tamiyaclub.com/forum/index.php?/topic/107511-black-friday-2024-uk-deals/

A slightly left field idea I have is to build this up, with a few of my own little toughness mods to the suspension and some 3d printed body mounts, but nothing much more, as a 4wd Blitzer type truck. with perhaps the Rock Socker body or similar (same wheelbase). I could probably also make my own shock towers if the geometry needs to change to keep chassis bottom out with the bigger wheels. 

Why? I'd do it with my son. I think it'd be a nice balance between a 4wd kit build for him and a handful of homemade mods, plus a truck wheeled 4wd basher really suits his kind of running, and this chassis is known to be fairly tough. He could build the buggy up first and we mod it after. 

I don't think I've ever seen anyone build one of these chassis up with truck wheels but we do it plenty with other buggies. Combining lightish brushless (say 13.5t) with the shortest gearing option for the chassis is probably ok. Aim I guess is kind of like our take on the Mad Van. 

What do you reckon? 

[Twinfan]

I think the gearing might be an issue as the shortest you have available on a Dragon is 8.86:1.  Using the Mad Bull as an example, that has a ratio of 9.33:1 and it has heat issues with its large wheels.

Otherwise it sounds cool  

[BuggyDad]

12 minutes ago, Twinfan said:

I think the gearing might be an issue as the shortest you have available on a Dragon is 8.86:1.  Using the Mad Bull as an example, that has a ratio of 9.33:1 and it has heat issues with its large wheels.

Otherwise it sounds cool  

Aren't the Mad Bull chevron tyres quite a bit bigger than say the Blitzer class ones, and I guess the heat issues are with brushed motors? If those points are both true I'm thinking I might just get away with it. But yes those ratios are a huge departure from what came before. 

Hmm then I wonder also whether a mod could be found to squeeze the motor across enough to go down an extra tooth. Perhaps I could CNC cut my own motor mount with different hole positions. I might struggle to cut aluminium but carbon would have the strength if not any help in heat dissipation. 

[Twinfan]

The suggested ratio for a 13.5T Hobbywing brushless is 7:1, so heat might be an issue for brushless.  Blitzer size wheels might be OK, as might Mad Bull/Lunch Box, I was just throwing the thought in there for consideration 

[Frog Jumper]

A couple years ago…

https://imgur.com/a/z3cYc4y
 

[BuggyDad]

43 minutes ago, Twinfan said:

The suggested ratio for a 13.5T Hobbywing brushless is 7:1, so heat might be an issue for brushless.  Blitzer size wheels might be OK, as might Mad Bull/Lunch Box, I was just throwing the thought in there for consideration 

Returning to this tyre diameter comparison I happened to do recently 

I'm somewhat more relaxed on this.

If the stock dragon tyres are at the smaller end of the buggy tyres I measured (83mm) then Blitzer tyres add 12% or Schumacher Vee-4s 18%. So stock gearing at buggy 8.86 should be adjusted to 7.91 with stock Blitzer tyres, or 7.51 on the Schumachers. But my hunch is that the stock Dragon tyres might be bigger anyway, as the Oval Blocks come out a fair bit larger in outer diameter than the astro 2.2s I was measuring (88mm). 

Where I'm getting to then is that gearing will be on the tall side but not unduly so if I choose a motor sensibly and aim at the smaller end of truck tyres.

Surprisingly, Oval Blocks are only 5mm smaller in diameter than Blitzer tyres. 

[BuggyDad]

55 minutes ago, Frog Jumper said:

A couple years ago…

https://imgur.com/a/z3cYc4y
 

Ooh yeah. That's more monster truck in looks to my eye, so I think I'd be going a little less far on wheel size. I can imagine pushing for more width though, whether through offset or looking for longer CVDs and printing arms to suit. 

[Frog Jumper]

44 minutes ago, BuggyDad said:

Ooh yeah. That's more monster truck in looks to my eye, so I think I'd be going a little less far on wheel size. I can imagine pushing for more width though, whether through offset or looking for longer CVDs and printing arms to suit. 

Those are 2.2” wheels with proline tires.  Just for perspective.

[BuggyDad]

42 minutes ago, Frog Jumper said:

Those are 2.2” wheels with proline tires.  Just for perspective.

Thanks. Looks like a real fun truck. How did you get on with it, esp ref motor temps but anything else too?

Yeah I'd use 2.2" wheels but I think your classic "truck" (but not "monster truck") tyres are smaller. The Blitzer and Schumacher ones above are on 2.2" wheels and they come out at 93mm and 98mm respectively.

It looks to me like 2.2" monster truck type tyres are more in the 120mm range, although I don't know about Proline's ones:

 

[Frog Jumper]

4 hours ago, BuggyDad said:

Thanks. Looks like a real fun truck. How did you get on with it, esp ref motor temps but anything else too?

Yeah I'd use 2.2" wheels but I think your classic "truck" (but not "monster truck") tyres are smaller. The Blitzer and Schumacher ones above are on 2.2" wheels and they come out at 93mm and 98mm respectively.

It looks to me like 2.2" monster truck type tyres are more in the 120mm range, although I don't know about Proline's ones:

 

Heat has always been a problem with the Dragon.  I think is has more to do with design than the wheels.  Ymmv…

[BuggyDad]

1 minute ago, Frog Jumper said:

Heat has always been a problem with the Dragon.  I think is has more to do with design than the wheels.  Ymmv…

Design in what regard, may I ask? Purely gearing do you think, or are other issues at play that we might find ways to address? Draggy drivetrain? Air flow to motor? Is your experience of heat with this chassis from brushed or brushless motors? There should be a significant reduction in heat when moving from brushed to brushless. Did you have heat issues even when running the smallest pinion size (13T)?

The impact of wheel diameter I'm concerned about is simply one of gearing - if the buggy has a heat issue with a given motor and pinion, increase the tyre diameter by 10% and I'm going to have to decrease pinion size by the same, essentially. Well, the wheels will be heavier and take more to get up to speed too, but I suspect that's a small part of the problem.

It is unusual for tamiya to design a car that's geared too tall. They have a habit of going the other way. 

I hope you'll excuse all the questions! 

[Frog Jumper]

I had issues with heat even with 1.9 buggy wheels.  I think the car is designed to run flat out for 10min max - the length needed for a 80s race with nicads.  After running it 20min on concrete, my can was redhot.  Gearing (pinion) could probably fix this, but I didnt explore that fix…

[BuggyDad]

15 minutes ago, Frog Jumper said:

I had issues with heat even with 1.9 buggy wheels.  I think the car is designed to run flat out for 10min max - the length needed for a 80s race with nicads.  After running it 20min on concrete, my can was redhot.  Gearing (pinion) could probably fix this, but I didnt explore that fix…

Ah. Well I think what we will do is build it stock first, because I can see if my lad can do a whole kit alone this way, then we'll have some test runs with different pinions then. I can use say a 15t pinion on stock buggy wheels to mimic the likely heat effect of a 13t pinion on truck wheels. I'll just go straight to brushless on this one, since there are known hest issues. 

Only after than would we get into truck mods. 

[Re-Bugged]

Sounds like a great project car 👍🏻

I used the Terra Scorcher chassis with a Sand Scorcher body on. With a 22t RC Core Brushed motor in was great on the firm close to the sea edge sand, & once it was up to speed on the soft stuff running 2.2 Turbo Scorpion rear wheels all round. It got a bit warm but never ‘thermalled’ the 1060 HW ESC.

It was perfect for the back garden with a Lexan Brat body on. It had the Javelin wheels on for that.

Not sure if the Saint Dragon is the the same front suspension as the TS but a Blitzer Beetle front body mount bolted straight on the front to work for both bodies @Grumpy pants might have one to sell you 😉.
Some of the spare body mounts in the Fighting Buggy worked for the back with the Brat fixed in some existing holes on the chassis, re drilling the body. Can’t for the life of me remember what pinion I went with but I am thinking of changing it to a 13.5t brushless that’s been perfect for most of my other runners.

You will no doubt have a lot of fun working on with your son and that’ll be the best part anyway.

[SlideWRX]

Kyosho Fazer monster truck tires/wheels are ~4.4 inches, 112mm max diameter.

[BuggyDad]

37 minutes ago, Re-Bugged said:

a Blitzer Beetle front body mount bolted straight on the front to work for both bodies @Grumpy pants might have one to sell you 😉.
 

That's hilarious - it was only last week I sent him that very part! I was thinking the Rock Socker shell for mine, so I'd go for two front posts. 

If yours is running on sand and grass with a brushed motor that's I guess around Superstock level (?) then I think it's a fair assumption that heat wouldn't be too big an issue with a 13.5 brushless, all else being equal. And on top of that if those wheels on the Brat running pic are 2.2s then those tyres are already very close to the size I'd go for. They look pretty high profile. Do you know which pinion you're running?

I do like those wheels too. They really suit it. Kyosho have a lot of nice wheels. 

[Grumpy pants]

5 hours ago, BuggyDad said:

That's hilarious - it was only last week I sent him that very part! I was thinking the Rock Socker shell for mine, so I'd go for two front posts. 

If yours is running on sand and grass with a brushed motor that's I guess around Superstock level (?) then I think it's a fair assumption that heat wouldn't be too big an issue with a 13.5 brushless, all else being equal. And on top of that if those wheels on the Brat running pic are 2.2s then those tyres are already very close to the size I'd go for. They look pretty high profile. Do you know which pinion you're running?

I do like those wheels too. They really suit it. Kyosho have a lot of nice wheels. 

Happy to help out if I can 👍

[jonboy1]

8 hours ago, Re-Bugged said:

 

I had a funny feeling I'd seen a TS with Blitzer-esque wheels and a Brat body on but for the life of me couldn't think where - should've known it would've been you @Re-Bugged 

Wasn't this one you won in one of the TC Competitions?

[Re-Bugged]

13 hours ago, jonboy1 said:

I had a funny feeling I'd seen a TS with Blitzer-esque wheels and a Brat body on but for the life of me couldn't think where - should've known it would've been you @Re-Bugged 

Wasn't this one you won in one of the TC Competitions?

Nah, wasn’t a comp win mate, just came about from one of those days sitting in the hobby room not having a kit to build, looking at bits n’ pieces swapping stuff around and hey presto that happened 

[Re-Bugged]

The Javelin wheel although smaller at around 46mm than the Turbo Scorpion’s 2.2 they are as close to the same outside diameter with there respective tyres on…

And I think the Rock Socker you have in mind would work well. It’s sitting up high on the Sand Scorcher body posts in this pic but should give you an idea….

 

( Yes it’s painted in PS-49 Anodized Blue without a backing colour, it was my first Lexan body so I was none the wiser then. I think they call it Patina nowadays 🤣)

 

I’m guessing I put the smaller pinion in it as I’d originally bought the Terra Scorcher for Racing By Post in tarmac trim.

[BuggyDad]

6 hours ago, Re-Bugged said:

The Javelin wheel although smaller at around 46mm than the Turbo Scorpion’s 2.2 they are as close to the same outside diameter with there respective tyres on…

And I think the Rock Socker you have in mind would work well. It’s sitting up high on the Sand Scorcher body posts in this pic but should give you an idea….

 

Those Javelin wheels especially are lovely looking. I've gone for some plain old white disc truck wheels for this project though for now, just because cheap and right size and they get smashed about. It'll be a budget project. 

I ordered the Toyota Prerunner body for it off TBG. The Rock Socker original is available in the UK for cheaper so I figured nothing to lose and I like the look of both. I think a truck body on this might get a fair bit abuse. 

Hey, I can see your Blitzer chassis in the background there - what are those crazy sand paddle tyres on it please? I started my Blitzer project as a beach runner and, although it might have got too nice now, at some point I can imagine both these trucks hitting the sand. 

[Re-Bugged]

The Satin Chrome on the Kyosho wheels doesn’t last long with regular use, so the white dish are probably better for bashing.

I don’t think those 2.2 Proline Sand Paws on the Blitzer are available anymore in that size. They do a narrower Sling Shot so you would need matching size wheels for them. 
 

https://www.prolineracing.com/product/1-16-sling-shot-fr-rr-2.2-sand-tires-mounted-12mm-blk-desperado-2/PRO1010110.html