XV-02 fan who speaks / reads japanese?

[smirk-racing 254]

Hi All, looking for a kind TC member who is fluent in Japanese.

 

This video shows some phenomenal jumping performance with the addition of a small spring to each shock (effectively creating a two-stage shock). I can't read any of the commentary in the video listing, or the comments the creator added to the video.

 

I would be very grateful if someone who is fluent in Japanese would take a quick pass through the video and perhaps jot down the key points...

 

 

[Nwc100 462]

It’s bit of a pain to do it this way, but I took a screen grab and then used google search to find the words and translate..

The second set of captions are ‘I’ve tried a variable damping valve’ 

Would be easier to find someone to translate it but if not it’s an option!

[FoxShot 280]

Ooooo, now that's funky. Gives me an idea

 

[Nwc100 462]

Ignore my idea, way too many subtitles, it does look very similar to another video I saw on YT where someone put some weight up high on I think it was a TT02, it was discussed a bit on here at some point as well, I’m sure someone will remember it!

[FoxShot 280]

Question. Are those Dzuz style pins stock on that chassis/model????

[OoALEJOoO 3256]

Quite an interesting idea. Something to think about is that the added inner spring will be dangling up & down along the shaft, which will probably scratch it over time and lead to oil leaks. Perhaps it could be somehow attached and centralized either at the base (connector side) or top (cylinder side).

[Rally! 150]

7 hours ago, Nwc100 said:

Ignore my idea, way too many subtitles, it does look very similar to another video I saw on YT where someone put some weight up high on I think it was a TT02, it was discussed a bit on here at some point as well, I’m sure someone will remember it!

It was me that posted that video. 

[Rvl 2 22]

On 12/14/2022 at 3:18 PM, Rally! said:

It was me that posted that video. 

I think if you glued 2 thinner spacers to the yellow spring it would reduce scratching.

[El Gecko 1432]

I don't speak Japanese, but I believe I've arrived at the same place as the video with regard to shock setup on certain cars.

For instance, I had been driving my old Traxxas Sledgehammer around with the shocks set very soft (only 4 shocks, not the full 8 from the factory), and I found that during high speed running, the truck had too much body roll for my liking, but more to the point, it was bottoming out the shocks on jumps, and even just general driving around, since the rear of the truck is quite heavy (the reason they used two shocks per wheel in the first place).

I really liked the traction and general driving characteristics of the softer shocks overall, especially for trail running, so I just decided to add bumpstops at first. It was a little better, but I still had to sacrifice too much up-travel to get back to a decent ride height.

Then I thought--what if I did spring-loaded bumpstops, essentially dual-rate springs? Why not! In my case, the secondary springs are a little longer and probably softer than the springs in the video, but I have them set up for my truck and a certain amount of sag. But the concept is sound. The truck drives more level, jumps more level, and still has the other suspension characteristics that make it fun to drive. Not sure about scratches and leakage as I don't run any oil in these shocks.

[BuggyDad 5385]

25 minutes ago, El Gecko said:

I don't speak Japanese, but I believe I've arrived at the same place as the video with regard to shock setup on certain cars.

For instance, I had been driving my old Traxxas Sledgehammer around with the shocks set very soft (only 4 shocks, not the full 8 from the factory), and I found that during high speed running, the truck had too much body roll for my liking, but more to the point, it was bottoming out the shocks on jumps, and even just general driving around, since the rear of the truck is quite heavy (the reason they used two shocks per wheel in the first place).

I really liked the traction and general driving characteristics of the softer shocks overall, especially for trail running, so I just decided to add bumpstops at first. It was a little better, but I still had to sacrifice too much up-travel to get back to a decent ride height.

Then I thought--what if I did spring-loaded bumpstops, essentially dual-rate springs? Why not! In my case, the secondary springs are a little longer and probably softer than the springs in the video, but I have them set up for my truck and a certain amount of sag. But the concept is sound. The truck drives more level, jumps more level, and still has the other suspension characteristics that make it fun to drive. Not sure about scratches and leakage as I don't run any oil in these shocks.

Interested to hear what springs you found? I'm tempted to try this on a buggy where I've gone softer and softer on the front damping, while becoming increasingly wary of jumps at the same time. 

[El Gecko 1432]

On 12/16/2022 at 5:37 PM, BuggyDad said:

Interested to hear what springs you found? I'm tempted to try this on a buggy where I've gone softer and softer on the front damping, while becoming increasingly wary of jumps at the same time. 

Not sure what it's from, but I found a single spring in my junk bin and cut it in half. The halves ended up around 17mm long each after the cut. Wire thickness appears to be around 0.4-0.5mm, so it doesn't have much spring force, but it's enough to hold the truck at my preferred ride height in addition to the stock springs.

It works on a buggy too! I have the same setup on my DT02, although I need to get stronger secondaries. I found some generic compression springs on Amazon 1x6mm OD at 10mm long, and I think the 1mm wire thickness and shorter 10mm length should make it more like a springy bumpstop than the softer/more progressive springs on the Sledge.

The video uses 10mm long springs from a 3D printer, which are all over Amazon too, but I didn't see any with the same dimensions as the video springs. I'm currently using springs from the 50395 F1 front upright set inside my DT02 friction shocks (only in the rear), and it helps a bit, but they really need to be a bit stronger. Doubling up is always an option too, although it makes for a messy look and would probably be more likely to mar the shaft.

[kontemax 1743]

A couple of harder front springs will do the job, simply.

Max

[El Gecko 1432]

2 hours ago, kontemax said:

A couple of harder front springs will do the job, simply.

Max

Simply, yes.

However, non-simply, adding harder primary springs affects the whole handling of the car, whereas the secondary springs only affect how the car jumps (thus the focus of the video). The main benefit is that each set of springs can be tuned independently, each for their own purpose.

When the chassis hits a jump, the sudden change in direction will bottom out just about any typical primary springs, causing the chassis to slap the ramp, unless you have them set quite stiff. Which affects the overall handling. Adding damping is also not the solution, for the same reason. It takes too much damping to keep from bottoming out, particularly on the ramp itself, and by then the handling will be negatively affected.

The idea here is that you have already set up the handling of the car to your liking on flat(ter) ground using the main primary springs, which for a 1:10 car in most cases is softer than you would want for hitting jumps. For example, I have fitted softer springs to the rear of my DT02, which creates the handling characteristics I like. However it will slap the chassis on even small jumps because the friction shocks don't provide much damping.

Enter the secondary springs: They act as bumpstops, simply keeping the chassis from hitting the ground. And instead of a hard bumpstop where the shock stops abruptly, potentially upsetting the chassis over a jump or even damaging something, the secondary springs soak up the impact and allow the chassis to stay settled and centered and in control.

[BuggyDad 5385]

8 hours ago, El Gecko said:

Simply, yes.

However, non-simply, adding harder primary springs affects the whole handling of the car, whereas the secondary springs only affect how the car jumps (thus the focus of the video). The main benefit is that each set of springs can be tuned independently, each for their own purpose.

Exactly what I'm interested in. I have gone softer for handling reasons. In my opinion it has made the car drive much better. For my DT-03 fronts, I think its handling has been transformed by softer springs, and softer damping. But its going to bottom out very easily as a result. This idea interests me because it might maintain those benefits at normal ride height while hardening it up in the last bit of travel. 

A hypothesis I have is that the issue is pronounced in this car because of its very rearward weight distribution. The need for the soft fronts is because it's so light at the front, but when landing a jump or hitting a big bump the weight of the whole car comes into play too. On my modded B64 truggy I don't perceive this to be an issue really.

Another factor may be that the B64 runs with more droop and has bigger shocks with longer stroke. 

[El Gecko 1432]

On 12/19/2022 at 3:16 AM, BuggyDad said:

Exactly what I'm interested in. I have gone softer for handling reasons. In my opinion it has made the car drive much better. For my DT-03 fronts, I think its handling has been transformed by softer springs, and softer damping. But its going to bottom out very easily as a result. This idea interests me because it might maintain those benefits at normal ride height while hardening it up in the last bit of travel. 

A hypothesis I have is that the issue is pronounced in this car because of its very rearward weight distribution. The need for the soft fronts is because it's so light at the front, but when landing a jump or hitting a big bump the weight of the whole car comes into play too. On my modded B64 truggy I don't perceive this to be an issue really.

Another factor may be that the B64 runs with more droop and has bigger shocks with longer stroke. 

It's possible the B64 has "progressive rate" springs, which would give a similar effect to the dual spring setup. Soft through the first part of travel, so you get the handling you desire, and they get harder as they compress, which would help keep them from bottoming out as easily as typical linear rate springs. Frog/Brat rear springs are progressive rate, which helps keep the tail from dragging.

[BuggyDad 5385]

3 hours ago, El Gecko said:

It's possible the B64 has "progressive rate" springs, which would give a similar effect to the dual spring setup. Soft through the first part of travel, so you get the handling you desire, and they get harder as they compress, which would help keep them from bottoming out as easily as typical linear rate springs. Frog/Brat rear springs are progressive rate, which helps keep the tail from dragging.

Funnily enough I was going to ask the question as to whether such things exist for RC. I don't think my B64 ones are, at least they look to me like they are uniform in thickness and coil shape throughout. 

If progressive springs exist that would fit the DT-03 fronts, they could be a real benefit.