Thunder Dragon First Impressions - Let's compare stories!

[nowinaminute 2815]

Accidentally posted this in the vintage section originally but of course it's not really vintage.

MODS: Please delete duplicate thread in vintage section if necessary.

 

I just drove my TD for the first time and wanted to share my findings and see if they align with other people running vehicles on the TS chassis family.

Currently, the setup is newrly all stock apart from a little diff putty in the diffs. I drive on loose dirt and sand etc a lot so I figured it might be beneficial on those loose surfaces. I only put a single small ball in each one so the effect isn't strong.

The motor is a Graupner sensored 13.5t about 2700KV running the medium pinion. Obviously a lot more grunt than stock but not monstrous, either.

I enjoyed it a lot on the whole! Seems like a great off road buggy and I was surprised by the aggressive turn in considering it's an oldie!

In some ways, it reminds me of the Hotshot and Boomerang but in other ways, it's quite different. It definitely has a lot more steering than the Hotshot even though the actual amount of steering lock isn't that great 

Suspension seemed quite nicely sorted although I might be tempted to remove some of the preload when running on soft off-road conditions. Even with the preload it seemed to soak of the terrain pretty well, though. Especially with a bit of speed.

I was impressed by the straight line stability overall, considering the amount of power. On smooth surfaces, it occasionally exhibited a little torque steer but nothing major. It's in this respect that it reminds me of the Hotshot/Boomer.

The only thing that made it difficult to go fast and straight in on-road situations was how sensitive it is to steering inputs! In more open spaces, it's not such a problem but when I was doing runs up and down a relatively narrow cycle path, I found even a slight attempt to adjust course to keep it straight would send it veering off quite aggressively which usually lead to an oscillating series of over-corrections. I found turning down the EPA helped along with being really light on the inputs but it certainly has an aggressive turn in! The fundamental stability seems very good, though.  Once it's actually pointing the right way, it will track pretty straight as long as you don't touch the steering.

On grass and dirt etc, it was superb! Those surfaces seemed to take the edge off the sensitivity but it still remained responsive and agile.  was impressed by how hard it could turn both on and off the throttle. It soaked the bumps up very nicely at speed and the 80s style ground clearance allowed it to easily get around on even fairly deep grass without being jacked up enough to be top heavy. 

So there you do, my initial impressions.

On the whole, I liked it a lot! A bit of a handful on-road sometimes due to it's very direct steering. If that can be addressed then great. But, even if that's just the way it is, I don't often drive on that kind of surface so it's not a deal breaker. I do as much driving on dirt/grass/sand etc as I can and I can already tell it will be great fun in those scenarios.

[alvinlwh 5895]

I am very nearly finished with my one, done the stickering yesterday, just need to paint one last tyre. My first impression at this time is that it is far heavier than I expect. 

 

[nowinaminute 2815]

I'll make another post about my impressions of the buggy soon but I just wanted to ask, are any of the arms particularly prone to breakage? @ThunderDragonCy? Just wondered if it's something I should get some spares of.

[alvinlwh 5895]

Having ran this car twice, my further impressions are:

First test run (NiMHs, stock tyres):

1. It is surprisingly good handling for a buggy, very stable in turns. In fact I think it is the best handling of all my cars. 

2. It will kill the stock tyres on tarmac fast. Well, this is my first buggy, so I cannot say I am an expert on pin tyres... 

Second test run (lipos, road tyres):

3. Pairing TZ with lipos seem to kill its handling, even with road tyres. It just flips over when turning at high speed. I am going to try extending the wheels and/or down gearing it to reduce its excessive speed. 

4. Body mounts suffers badly in a crash, probably due to the weight of the motor pressing directly down on them. 

Other observations:

5. Not much hop ups for this chassis. I only got the metal A5, bearings and a TZ  for it. 

6. It is rather large (compared to my other cars) but has a surprising lack of space. Ideally, I will run it with a big heat sink ESC but there is no room under the driver (will explore behind the driver instead when I have the time). 

[Alangt4 123]

I was running mine with this old demon power motor and 2s lipo. Steering is pretty sensitive and high ride height did cause it to flip until I got the feel of it. Maybe a slower servo would help as it has a savox or similar modern one in. Ran back to back with super hotshot and the top force both running super stock BZ and 2s lipo. Much better handling than the super shot, as the small turning circle of it takes more driving skills.

not sure what turns this motor is but seems a good balance for it.

[rwordenjr 1890]

49 minutes ago, Alangt4 said:

I was running mine with this old demon power motor and 2s lipo. Steering is pretty sensitive and high ride height did cause it to flip until I got the feel of it. Maybe a slower servo would help as it has a savox or similar modern one in. Ran back to back with super hotshot and the top force both running super stock BZ and 2s lipo. Much better handling than the super shot, as the small turning circle of it takes more driving skills.

not sure what turns this motor is but seems a good balance for it.

that motor looks in good shape for how old it is !

[alvinlwh 5895]

51 minutes ago, Alangt4 said:

, as the small turning circle of it takes more driving skills.

Yes, probably my poor driving skills. Just surprised at how much difference 0.2v makes between stable full throttle turns and a rollover. Was expecting better road holding with road tyres but guess the speed is just too much. 

[ThunderDragonCy 7886]

7 hours ago, nowinaminute said:

I'll make another post about my impressions of the buggy soon but I just wanted to ask, are any of the arms particularly prone to breakage? @ThunderDragonCy? Just wondered if it's something I should get some spares of.

Nah. Arms are very bendy, hence difficult to break. A5 and B8 are the only breaky bits. 

[nowinaminute 2815]

Keep forgetting to post again but here's some recent thoughts. Basically the same as what I've already said.

I find the steering very "on the nose" on some surfaces. It seems like the slightest touch of the steering will send it spinning out on tarmac and it can be a real pain to keep it in a straight line because when you try to make tiny corrections, it wants to shoot off in that direction. It's almost like I can't make little corrections to keep it straight. Weird thing is, when it's actually going in the direction you want, it tracks as straight as an arrow, it seems to have decent straight line stability but it's like it over reacts to the most subtle of inputs to correct course and you end up zig zagging.

Might be exasperated a little by the brushless motor although it's only a 2700kv so not monster fast.

I know they are all different designs but my DT-02 and 03, Hotshot, even lunchbox and Kyosho Mad van etc just seem like much less hard work to drive fast in a straight line.

Is this normal? Have I messed something up during assembly? I've tried 3 servos. Started off with a fast one so changed it to a Hobbyking Hk15138 and finally an MG996r, the slowest of the 3 but none have really dulled the over enthusiastic responses. 

In more open spaces, where going in a very specific direction is less important, it feels much easier drive but I've found the local footpath is a good way to test out the characteristics of different vehicles and this one is by far one of the most difficult I've had in terms of going along the path without ending up in the grass either side.

Just to give you an idea of the scenario, here's Kumamon on the same path, packing a much faster 3800KV Castle system and nearly bald rear tyres but somehow being much less hard work!
 

 

[Alangt4 123]

Yeah it is pretty twitchy. The wheelbase is shorter than a top force (I think) and it’s way higher in ride height. It turns very tight if you have steering set the same. Using an older slow servo you don’t notice. it also looks to have less rear toe and less camber than top force. I use top force as a reference as that car has great steering and so precise yet smooth to drive. The hot shot series steering is much slower and less so takes more effort to get it to turn sharply on high grip surfaces.

I think these things give it those traits and I will have to take some time to dial them out.

[ThunderDragonCy 7886]

Very "on the nose" is the thing I spend so much time wrestling out of my thunder dragon. First thing to do is get rid of the stock wheels and tyres and get a 2.0 or 2.2 setup where you can put narrower fronts on with much less grip than the rear. On grass I used to run 2.0 egress wheels with Schumacher full spike rear and mini spike front. I now run JC Racing egress style 2.2s with cut stagger front and mini spike rear. 

Another thing thaf calms down turn in is thicker front damper oil. Go much thicker if you have some, or if not put the single hole damper piston in. The monoshock is doing the job of two dampers so makes sense to give it a bit more support. After that a stiffed front spring also helps, but certainly changing the front damper piston is zero cost. 

[alvinlwh 5895]

43 minutes ago, ThunderDragonCy said:

Another thing thaf calms down turn in is thicker front damper oil. Go much thicker if you have some, or if not put the single hole damper piston in. The monoshock is doing the job of two dampers so makes sense to give it a bit more support. After that a stiffed front spring also helps, but certainly changing the front damper piston is zero cost. 

This is exactly what I plan to do after reading this:

https://www.rcscrapyard.net/uk/tips.html

CAR TURNS IN TOO QUICKLY.

A/ Stiffer front oil.

B/ Lighter rear oil.

C/ Raise ride height slightly at front.

D/ Lower ride height slightly at rear.

Will #700 oil with 1 hole be too much you think? 

[ThunderDragonCy 7886]

2 hours ago, alvinlwh said:

This is exactly what I plan to do after reading this:

https://www.rcscrapyard.net/uk/tips.html

CAR TURNS IN TOO QUICKLY.

A/ Stiffer front oil.

B/ Lighter rear oil.

C/ Raise ride height slightly at front.

D/ Lower ride height slightly at rear.

Will #700 oil with 1 hole be too much you think? 

I would give it a go. I went to something like that setting on my OG Thunder Dragon.

[alvinlwh 5895]

My main complain about the TD is when it roll, on road, its top body mounts get damaged easily. Hoping to get some replacements without needing to buy a whole parts tree, anyone got any suggestions?

[taffer 948]

Shapeways 3d printed have just bodymounts

[alvinlwh 5895]

33 minutes ago, taffer said:

Shapeways 3d printed have just bodymounts

I found front ones but no rear ones. You got a link? Thanks. 

[taffer 948]

https://www.shapeways.com/product/C8S5VS8B4/tamiya-thundershot-b10-b15-body-mount-parts

[Alangt4 123]

2 hours ago, alvinlwh said:

My main complain about the TD is when it roll, on road, its top body mounts get damaged easily. Hoping to get some replacements without needing to buy a whole parts tree, anyone got any suggestions?

What motor and servo are you using and what surface? The buggy has high ride height and twitchy steering for the off road bumpy running back in the day with slow servos. Replacing body mounts is one thing but it’s setting it up for what you run it on will stop it grip rolling in the first place. Or at least limit it!!

[alvinlwh 5895]

27 minutes ago, Alangt4 said:

What motor and servo are you using and what surface? The buggy has high ride height and twitchy steering for the off road bumpy running back in the day with slow servos. Replacing body mounts is one thing but it’s setting it up for what you run it on will stop it grip rolling in the first place. Or at least limit it!!

At the moment, I am still testing it. Only made 3 runs since completing it.

Servo is just some el-cheapos' that comes in £20 for pack of 4.

Motor is TZ.

Surface is tarmac.

First run: NiMH, stock tyres and 17T pinion - Runs perfect, straight as an arrow and turns like it is on rails at full speed and full lock. Chews up the tyres though.

Second run: Lipo, Fastrax Arrows (road tyres) and 17T pinion - Flips endlessly.

Third run: As second but with 14T pinion - Still flips

Second and third runs, very wet and cold surface as well.

As mentioned above, I will try firming up the front shocks before trying again. It was also suggested that I use the EXP on the Tx to reduce the turn rate.

I had considered replacing the body mounts with magnetic ones, but rejected the idea as, if the body flies off, the driver will be getting some road rash.

I will run it off road/mixed eventually but is testing at the moment, so using a flat smooth surface.

[Alangt4 123]

You will need to do a couple of things. However it will not be suited to off road/loose conditions so much then of course, as that’s how’s it’s set up now.

-firm up front end

-reduce steering rate

-add a little toe in at the front to help stabilise steering response.

if that is not enough then:

-reduce ride height-especially at the back end.

-soften rear end also

since it’s tarmac the high ride height will not be doing any favours!!

 

[alvinlwh 5895]

38 minutes ago, Alangt4 said:

-firm up front end

-reduce steering rate

-add a little toe in at the front to help stabilise steering response.

Yes, as mention earlier, going to put in #700 and 1 hole. 

What is the meaning of reducing steering rate? EXP on Tx? 

Already on toe in, I normally set my cars to toe in. 

[Alangt4 123]

Yeah if you can trim the steering response/exp of your tx.

hopefully it all doesn’t take too much off the steering as the sharper steering is a big improvement over the hotshot series. At least starting with one thing at a time you can get the balance you want.

 

[alvinlwh 5895]

19 minutes ago, Alangt4 said:

Yeah if you can trim the steering response/exp of your tx.

hopefully it all doesn’t take too much off the steering as the sharper steering is a big improvement over the hotshot series. At least starting with one thing at a time you can get the balance you want.

I am still exploring the effects of EXP on the Tx but will not be able to fully do so until I got the chance for another run. One thing that was never picked up on was it roll with a switch to lipo, was running real sweet with NiMHs. However the switch also coincide with a chance from stock pins to road tyres. 

So there are still a number of factors for me to consider. 

1. The additional power of lipo. 

2. The lighter weight of lipo. 

3. The additional grip of the road tyres. 

Well, like you said, it will take me time to get its balance right and I am just starting out. 

[taffer 948]

Mmmm mine doesn't flip with 2s lipo, 13t pinion and bz motor....but yes the tyres wear quickly! When bald they are even more fun with easy power sliding

[alvinlwh 5895]

13 minutes ago, taffer said:

Mmmm mine doesn't flip with 2s lipo, 13t pinion and bz motor....but yes the tyres wear quickly! When bald they are even more fun with easy power sliding

Which is why I said the flips happened at the same time when I switched over to road tyres as well. Not sure if that is a factor but now I got cheap Fastrax pins on to test. First time it flipped was on 17T and second time was 14T (cannot find 13T but will hardly be much different to yours). 

Something else just popped into my mind, on stocks, the tyre sizes are same f/r. But the sets I got are narrower fronts and someone said narrow fronts sharpen up the steering, could be a factor here too... Maybe I will pop on rears all around to test.