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Yalson

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About Yalson

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  • Location
    London, UK
  • Interests
    Kyosho Optima Mid and Lazer ZX-R, Marui Hunter and Galaxy RS, Tamiya Grasshopper and Hornet, random RC bits and pieces

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  1. Is that Home Alone on in the background? Ha ha! We watched that the other week. My daughter loved the slapstick bits.
  2. Theoretically, yes. But in practice you will inevitably be a bit off centre and you will end up with wheels that are off centre and make your car drive like a rodeo bull.
  3. BITD I used to run a hand-wound 12x2 in my Mid on-road competitions with a pretty stock drivetrain. Never had any issues with it, apart from it sometimes eating idler gears and once a 64dp spur. And I know other drivers who used to run even hotter winds than that. I think a 10x1 was the lariest wind I saw used in a local meeting, although I know there were motors down to 8x2 available. Back then it was more a problem of ensuring your battery lasted, rather than whether your gearbox could take it.
  4. Is that... a spray can lid?
  5. Well that is... tiring. Rather than RC, that seems closer to slot car racing (which I also used to do, much longer ago). Because the surface is so regular and grippy, the cars are running really soft suspension with barely any ride height, which means you can hear them bottom out and thump into the carpet when they land every jump. If nobody has considered applying a self-adhesive PTFE coating to the outside of the undertray to reduce friction and stop the car from dragging at that point, then they're not really trying. I mean, it's cool, but it's only off-road by the most literal of interpretations.
  6. Yalson

    Pinion gear mystery

    I just looked it up and the pinion on a DT-03 is not compatible with your Shadow anyway. The gear pitch on the Shadow is 32dp (metric), while the DT-03 uses .8 module (which is an imperial measurement). People have posted in other threads here before that the two systems are almost equivalent (.8 module apparently works out at roughly 31.75dp). But if you use them together for any length of time, the gears will inevitably chew each other up as they are fractionally different sizes and therefore one gear will always be trying to push teeth into gaps that are just too small for them. Stick to proper 32dp pinions (there are plenty of them available on eBay) and you should be OK. And make sure you keep the two pitches separate, or you could mess up the gears in both cars. I feel for you with the problem of the hole in the gearbox case being too small to get the pinion through. I have a Raider that uses 32dp gears and it has exactly the same issue. It is hugely frustrating and very poor design to have to take the gearbox apart to swap pinions.
  7. Yalson

    Pinion gear mystery

    The gears on the Shadow are 32dp. Kyosho used .6 module gears on the Mid, equivalent-era Ultimas and some early Lazers (they switched to 48dp at some point in the production run, for some reason), but pre-Mid Optimas, Aero Streaks, Shadows and various other earlier or simpler models used 32dp gears. And please, don't tell people "the plastic will morph to match if you let it run without load". Because if the gears are of different pitches, it really, really won't. It will just ruin your gears. The wear in the picture seems to be even all the way round the pinion, which suggests it has been set up with too much slop between the pinion and the spur and they weren't meshing correctly. @esmuz, you may need to now replace the spur and the pinion to get a good mesh between the two, as once a gear is worn like that it won't come back again. If you are using a Le Mans 05, you might also want to increase the pinion size to a 16t (OT-52) or a 17t (OT-53) or an equivalent 32dp pinion from another manufacturer. I am not certain what part number the spur is (looks like no 26 from the SB-6 diff parts bag, but you'd know better than me) but they seem available, too. Although you might have to order an original parts bag from the USA to get one. Good luck with it!
  8. Yeah, the physics of 1:10 RC do not line up with 1:1 cars at all, as the physics always work at 1:1 scale no matter how big the model is. This is also why the aero doesn't work: the 1:10 scale wings – which are not a tenth of the size of 1:1 wings, but one thousandth of the size, as the wing is reduced to a tenth of the size IN ALL THREE DIMENSIONS – work at 1:1 scale, and at that tiny size they are basically ornaments. RC cars also do not have underfloor aero, as they are hollow underneath and their chassis are full of holes. Given that on most racing cars the underfloor elements generate more downforce than the wings on top, this means they are hindered badly. That said, I have been wondering if it would be possible to create a ground effect underfloor on a Tamiya 1:10 circuit racer, like a TT-02 or something similar. You can't fit proper ground effect venturi tunnels as it has a flat chassis, but there might be other ways.
  9. Grip roll is an odd thing. I have never been in a position to experience it myself, as I used to run buggies years ago, rather than your closer-to-scale Tamiya cars and trucks. However, it seems to me that grip roll is a totally different phenomenon from the basic oversteer/understeer dynamic and effectively rules them out altogether. Oversteer and understeer relate to the ability of a car to hit a theroretical point at the apex of a corner under ideal conditions. Understeer will force the car to "run on" and miss the apex. Oversteer will cause the car to flare its tail out, lose traction and either turn in short of the apex or lose control and spin out. The idea is to balance the car at a point on tbe scale between the two which is advantageous to the personal style of tbe driver. Grip roll short circuits this by not allowing the car to slide or drift, making both understeer and oversteer impossible or irrelevant. The centrifugal force that forces the understeering car wide and makes the oversteering car spin instead digs the outside tyres of the grip rolling car into the racing surface and its sideways momentum simply rolls it over. This is particularly a problem for "scale" type saloons and trucks, as they have a narrow track (ie they're not very wide in relation to their length), they often have a high centre of gravity (ie they have a tall bodyshell in relation to their width), and often have a lot of grip on already grippy surfaces like carpet. In relation to @Mad Ax's comment about hardening the front suspension on the truck increasing the problem, this may be because it is the tyres and track surface doing all the work in the grip roll. Having softer front suspension will allow the model to "load up" the affected corner, absorbing some of the sideways momentum contributing to the grip roll. Hardening the suspension under normal circumstances will reduce mechanical grip and allow the model to slide more. But those trucks probably have a high CoG and tyres with high sidewalls that flex enough and contribute enough mechanical grip on their own that they will still grip roll anyway, but now because there is no mechanism absorbing any of the forces, it will now reach a critical point very suddenly and tip over with no warning. Without actually driving one of these cars I can't really recommend a way of solving grip roll. The idea is so alien to my experience driving 1:10 buggies 30 years ago that it kind of melts my brain. Like modern F1, it could be that modern RC is so specialised in its requirements that the normal theoretical solutions no longer have any relevance. It could be that the driving skills required are completely beyond my understanding. It could just be that you need to keep the cars perfectly on line and drive them in straight lines as much as possible. But where's the fun in that? That's not RC, that's more like maths.
  10. The main thing is that adding grip or softening the suspension at the front will increase turn in and add oversteer (the tendency for the rear of the car to slide, or the car to spin). Adding grip or softening the suspension at the rear will add understeer (the tendency for the car to drift wide of the intended apex at a corner). All car set-up is basically a compromise between these two attributes. There are a lot of ways of influencing these tendencies (you can influence both through the use of the throttle, for example) and 2WD and 4WD cars react differently to different inputs, but those are the basics. Experiment with these and you will quickly learn what works for your car. One other thing that might be relevant here, given your mention of a home-made rear wing: aerodynamics play very little part in RC car handling characteristics. Anyone who says otherwise is talking nonsense. The cars are too slow and the alleged aerodynamic surfaces too small to do the job they claim to do. The wings at the front of a 1:10 scale Tamiya F1 car, for example, are purely for show. They have no effect at all on how the car handles and they could be removed without any penalty. The big bucket wings on RC racing cars do have an aero effect, but provide very little downforce and instead are only intended to create drag at the rear of the car in order to provide a degree of directional stability, especially over jumps. So concentrate on chassis set-up and tyres. Everything else is incidental until you get to about 50mph, when aero starts making a difference.
  11. Off the top of my head, I seem to recall that the Ninja preceeded both the Terra Scorcher and the Sonic Fighter. It was a very handsome machine, with a svelte but tough chassis that it was sometimes difficult to fit everything into, but was vastly superior to the Boomerang, which was positively agricultural in comparison. My friend had one and it never let him down, although cutting square holes in the shell for the shock towers to fit through was always a silly solution that was going to end in tears.
  12. While I appreciate the purity of your approach, I fear you'd end up with a lot of very short races that way.
  13. A few. But more importantly, the Lazer just needs cleaning and tidying and maybe a new body. I need to get myself back into it.
  14. Yalson

    Stigma

    Not to mention the fact that Schumacher's Top Cat had lay-down inboard front suspension years before either design was introduced. Talk about two bald men fighting over a comb. Schumacher ended up having to delay the re-release of the Top Cat for a considerable time while they tried to negotiate with Traxxas over their right to use a design innovation that didn't belong to Traxxas in the first place. Solely so Traxxas didn't later decide to sue them and bankrupt them.
  15. Yalson

    Stigma

    They try to use their size and dominant market position to force competitors out of the market through the use of spurious patent claims, often on innovations that were not theirs in the first place. I am not going to go into too much detail here, as I am certain this has been covered elsewhere on the site. But it's a terrible practice and it does neither the market nor us as RC enthusiasts any good at all.
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