Jump to content
JakeRobb

Resurrecting and hopping up an old (Super) Hornet

Recommended Posts

Hi, I’m Jake. I'm new here. 

In 1990, on my tenth birthday, my dad took me to Rider’s Hobby Shop. We came home with a Tamiya Hornet, Futaba 75MHz radio set, and a massive Pro-Tech battery charger for the 7.2v NiCd battery. 

We assembled it together, and to make a very long story short, I made a lot of great memories with it throughout my adolescence and into college. In ~2000, after a hard crash+tumble snapped the bumper mount off the main tub and tore the flimsy top shell apart, I bought a Super Hornet and moved the electronics over, taking the opportunity to upgrade to a “350” motor, 8.4v battery, and a new receiver and (still mechanical, servo-actuated) speed controller with BEC. I never painted it or applied any decals; I thought it looked cool all black and really only cared about going fast. I still think of it as a Hornet, but it’s almost 100% Super Hornet now. I like the rigid top shell. 

I have brought it along as I’ve moved homes a couple of times since then, but it’s been close to twenty years since I’ve done anything more than glance up at it on the garage shelf and remember it fondly. 

My father-in-law found a bunch of Xmods (1:28 scale Radio Shack RC cars) on eBay this summer, and now my kids and their cousins are RC-obsessed. Last month, when my eight-year-old daughter saw the Hornet on the garage shelf and asked me what it was, I told her, and she got excited, so I decided I needed to bring it back to life. A quick evaluation:

  1. It was VERY covered in garage dust and detritus. 
  2. The NiCd pack hadn't been used in well over a decade, and I didn't know if it'd hold a charge.
  3. The transmitter didn't have power, even with a fresh set of batteries.
  4. The front wheel bearings seem to have disassembled themselves. They still roll really smoothly (they free-spin for at least a minute with a quick spin by hand) but the covers have fallen off and the bearing balls are exposed, so they won't keep running that smoothly for long.
  5. The gearbox doesn’t seem to have any lubricant in it, and I don’t seem to have the bottle of lube that came with the car (I guess I was a little too hasty when I rebuilt it in college?).
  6. I don’t seem to have a proper, unbent pair of tie rods.

I gave it a quick blast with the air compressor, then a thorough wipe-down. It’s looking decent now. I plugged the battery pack into the charger and let it trickle overnight, and I went online and found a nice set of replacement ball-bearings. I also grabbed a tube of Tamiya Cera Grease GH and also a bottle of silicone lube. I'm not sure which is more appropriate and would love any advice you guys might have. I also sprung for an ESC (Kyosho KA060). I looked for tie rods, but didn't find anything that seemed like a direct replacement, so I decided to put that off until later.

The Futaba FP-T2NBL "Attack 75" transmitter had two issues: one of the springy metal tabs that holds the batteries in broke off, and the point on the PCB where the antenna wire hooks in also broke off. I'm not great with a soldering iron, but I didn't have a lot of options in the short term. Luckily, I was able to remedy both issues!

At this point I had a working car and a working transmitter, and the battery had been trickle-charging for close to 24 hours, so before I continued I decided to hook everything up and give it a go. It worked! I got about two minutes of runtime and all seemed good, so I handed the transmitter off to my daughter to let her have a try. It went ten feet and then stopped; the transmitter indicated that it no longer had power. My soldered connections were holding and did not appear to be the problem, but it was now beyond my ability to diagnose and repair -- and my daughter was really upset because she didn't really get to drive it. Understandably, having it work for ten feet made her feel worse than not getting a chance at all would have.

So I went online in search of a replacement, thinking that it would be cool to convert to 2.4GHz too. Imagine my disappointment when I learned that anyone who prefers stick-style controls is stuck with exactly one currently sold option: the Futaba 4GRS. $380!! And weird looking. Or, of course, you can get an air controller with way too many buttons and controls for a bazillion dollars, or you can get a pistol-grip controller. 

I imagine most of you are using pistol grip controllers. I won't do that, because frankly, I hate them! The Xmods use them. If you like them, that's great for you, but I find them unintuitive and unergonomic. It's hard to be precise with the throttle (especially in reverse), and the steering wheel being sideways always screws me up. No way I'm spending $100+ for one of those. Imagine if, after many years of the current design, some car manufacturer decided to orient the steering wheel sideways, and also redesigned it so it looked like a wheel and tire -- and then eliminated the brake pedal and modified the accelerator so that you had to hook your foot under it and pull up to slow down or reverse. Inexplicably, the entire industry follows suit, until at some point there is only one car on the market with the controls we all know today -- and it's a Tesla Model Y. Expensive, weirdly proportioned, tons of unnecessary bells and whistles, and pretty much nobody has one.

After some research, I discovered the 4GRS's predecessor, the 3GR. Before I realized that there was a 40MHz version and a 2.4GHz version, I almost bought one of the former -- but I caught the distinction just in time and continued searching. I eventually found one for sale on eBay in Germany. Between shipping and currency exchange, I paid almost $300 (including receiver and two servos), and it's going to take a month to get here, but it meets my needs and cost less than the 4GRS.

At this point, I said "screw it" to the idea that I was not going to spend much to get this thing working again, so when I went online and started searching for replacement tie rods and wheel bearings. I wasn't super happy with what I found; there doesn't seem to be a drop-in upgrade with something better than the glorified paperclips that came stock. Lots of good stuff, but nothing that is clearly compatible. But then I found a post on here about the CRP FX10 conversion, and so I ordered one of those kits. It's not 100% clear whether the one I ordered includes tie rods, but I'm going to wait for it to show up, get it installed, measure for tie rods, and then find a suitable beefier set. For now, I have just straightened what I have -- but depending on when I complete the retrofit vs when the 3GR shows up, I might not need them at all.

In this new "spend all the money" mindset, I also bought a bunch more hop-up parts: a BZ motor, replacement shocks/springs, and metal versions of a bunch of stuff: front bumper, steering arms, wheels, rear wheel hubs, a 12mm hex adapter so I can try some other wheel and tire combinations, and some of the rear suspension bits (including what seems to be a swaybar). And then I decided I wanted to try the LiPo world. I decided on 2S to keep the voltage similar, and then looked around. My NiCd pack was 1500mAh, which always yielded a disappointing run time, and I know the kids will not have much patience for the run-charge-run cycle I grew up with, so I wanted the highest capacity I could get. I took some measurements and found an 8000mAh battery that seemed like it would fit. I also bought a nice little charger.

Then I started reading up on what I would need to know about LiPo. Balance charging, storage voltage, LVD and LVA, etc. The ESC I ordered has a built-in LVD, but I ordered an LVA that hooks up to the balance lead and plan to set it up to alarm shortly before the ESC shuts down, so that I get a little heads-up and can direct the car back towards me in its final moments. 

At this point, I'm still waiting for most of the stuff to arrive, but I have the charger, the ESC, and the batteries (Amazon sent me two...?  🎉). The charger came with a fire bag, too. I tried putting the battery into the Super Hornet's battery compartment, and it fits in terms of height and width, but sadly it is a few mm too long. However, I got out my dremel and was able to make room! It now fits perfectly -- tight enough that it won't bang around in there, but still easy to slide in and out. I also dremeled some clearance for the battery connector leads on the top front of the battery compartment. I also dremeled off the stands where the resistor and heat sink used to sit, just ahead of the spoiler, and I plan to mount the ESC there so it can get some airflow over its cooling fins.

Next, I found that the battery interfered with the steering servo (Futaba S148). Drat! I looked at the specs on the servo that's coming with the 3GR, and it's about the same, so I knew I had to do something. I knew about low profile servos, so I looked into those a bit. I looked up the speed, torque, and sweep specs on the S148 so I could be sure to get something at least as good functionally, and took some measurements of the chassis to figure out what I'd need to do. After a bit of googling, I found the wonderful servodatabase.com, which made it really to figure out what would and wouldn't work. At first I was pretty disappointed -- everything that seemed like it would fit was well short on torque. But then I found the Hyperion HP-DS11-AMB, which is a sub-micro servo intended for RC helis. It's SUPER tiny, has close to double the torque of the S148, and it's quite a bit quicker too. It has a 140° sweep vs the S148's 180°, but I can live with a bit less turning radius (plus I can always take advantage of the extra torque and compensate where the tie rod meets the steering arm). I'll have to do something custom to mount it, but that's okay. I'll figure it out after the front-end kit is installed.

So, right now I have a neat looking project. It flashes and beeps when I turn it on, but it doesn't move. But soon, it's going to be awesome! I'm expecting about an hour of runtime on a charge, which means the kids and I should be able to play as long as we want by swapping between the two batteries.  The metal front bumper I bought has a couple LED headlights built in, so I'll wire those into the third radio channel. I still had the original, unused set of body decals, and I'm going to have my daughter paint and decorate the body any way she likes. I'm expecting pink and purple with unicorns and rainbows, which will be hilarious!

It'll probably be December by the time I have all the parts and everything is installed. I live in Michigan, and snow can get in the way of this kind of fun. However, my in-laws live on a small lake, and I was thinking it might be fun to drive this thing on the ice! I don't imagine it'd be very controllable, though. I looked around a bit for studded RC tires, and I found a couple things, but they don't seem like they'll fit. That was before I found the 12mm hex adapters, so I can probably find something that will work. 

Also, I'd love to experiment with 3S or more in the battery area. My ESC can handle 3S, and my charger can handle 6S. The BZ motor says it's good for 7.2 volts, and I'm sure it can handle a bit more -- I ran it for those few minutes at 8.4, and a fully charged 2S should be about 8.4 too. But 3S is 10.5-12.6, and I'm curious to know how the BZ would handle that. Would I burn it up?

Anyway -- hi! Any thoughts or suggestions on my work so far or my plans? I know I'm not exactly making sound financial decisions, but I just started a new job with a 36% raise (44% if you include bonuses), so I can afford it. With the upgrades, my hope is that the car will be robust enough to survive a good bit of abuse by the kids, and fun enough to hold their attention. My only worry is that next I'll need to build another just like it, because I have two kids! Or maybe three more just like it, because they have two cousins. 😅

On that note, what's a modern RC that would offer comparable or better capability and performance? I'd want something similarly fast (25-30mph), 1/10 or 1/8, capable of paved and unpaved surfaces, and sturdy enough to survive some crashes. 4WD would be cool. I know Tamiya has a bunch of more modern buggies, but I'm having the hardest time figuring out which ones are the latest and greatest or what the pros and cons of each would be (or if I should be considering other brands). Bonus if it can use the same set of batteries, but I'd also be happy to experiment with higher voltage stuff. The 3GR has a ten-model memory, but I'd probably get a couple extra controllers so the kids can run them together. Probably pistol-grips, because they don't care like I do. (I should probably ask this in a different subforum...).

 

  • Like 5

Share this post


Link to post
Share on other sites

probably better off buying a new pair of freshly minted rere Hornets for the kiddies, MadBull might look more comical too. Or better still try DT02/3 modern chassis. 

Futaba is premium priced top end radiogear. For cheap 2.4gHz gear these many yumcha brands these days, FlySky brand does the job just fine. 

  • Like 1

Share this post


Link to post
Share on other sites

To push back a little on the "premium priced top end" characterization, I think the prevalence of cheap Chinese radio gear forced Futaba to introduce less eye-wateringly priced gear that still maintains their high standards of quality.  I'm thinking in particular of the FHSS-based gear like the 3PV, which while more expensive than the FlySky equivalent, is still quite affordable and comes with the benefit of Futaba peace-of-mind...

  • Like 4

Share this post


Link to post
Share on other sites

Sounds like the bug bit you again!

Something like a TD2 Astute might be a good choice for your next one. It’s thoroughly modern (ish), and won’t require many hop-ups at all for reliable speedy running.

As for servos, take a look at Savox. They’re a rock solid choice and easy to find.

Best of luck, and have fun!

Share this post


Link to post
Share on other sites
On 11/11/2022 at 1:13 PM, WillyChang said:

For cheap 2.4gHz gear these many yumcha brands these days, FlySky brand does the job just fine. 

I looked at FlySky. As far as I can tell of their stick transmitters are two axes per stick. 
 

I know you can just ignore the left-right axis on the left stick and the up-down axis on the right stick, but that doesn’t provide the experience I’d be looking for. Do any of those controllers have a way to physically lock each stick to a single axis? 
 

I already ordered the 3GR, but I’d still be interested to know if such a thing exists. 

Share this post


Link to post
Share on other sites
2 hours ago, JakeRobb said:

I looked at FlySky. As far as I can tell of their stick transmitters are two axes per stick. 
 

I know you can just ignore the left-right axis on the left stick and the up-down axis on the right stick, but that doesn’t provide the experience I’d be looking for. Do any of those controllers have a way to physically lock each stick to a single axis? 
 

I already ordered the 3GR, but I’d still be interested to know if such a thing exists. 

There are some 3d printed parts to lock them to a single axis. I don't know if you would buy them off ebay or shapeways though as I use mine for  yachts and its not an issue. For very cheap Futaba also have the T2HR which is basically what we used to have BiTD with no options except channel reverse and trim.

25 - 30mph should be easy enough with 2S batteries. Brushless motors have a lot more torque so you can gear them much higher than brushed motors 

Share this post


Link to post
Share on other sites

So, the Hyperion HP-DS11-AMB servo is here, and it is tiny!

A wrinkle I didn't anticipate: it has a 15-tooth pinion that measures a bit under 4mm. My servo saver accepts a 6mm 25-tooth pinion or a 4.8mm 21-tooth pinion.

The Hyperion came with some horns, but none that are quite right. I can cobble something functional with one of them, but it won't have a servo saver, and the toe will vary through the steering arc, which is obviously not ideal.

I've been looking, and I have not found an adapter that will fit the 15t pinion and either a 21t or 25t horn. Do these exist somewhere? I took a $7 gamble and ordered a pack of these, but I don't expect any of them will be quite right (assuming the photo is accurate, those all have 18 teeth on the outside). If not, do other options exist? A linkage that connects the tie rods together and then moves that whole connected assembly (basically making the servo horn into a proper pittman arm) would work, but I'd still need some kind of servo saver. Is there something out there that I can adapt?

Lots of other parts have come in as well. I've installed ball bearings on all the wheels and throughout the gearbox, mounted the ESC, and mounted the new shocks and metal steering knuckles. It's coming together nicely! I've slowly charged and discharged my new LiPo packs a couple times (then returned them to storage voltage of course) so that they're conditioned and ready for use.

Share this post


Link to post
Share on other sites

What I'd really like is a symmetrical setup. I feel like I could cobble something together using a few turnbuckles and a couple other parts. Here's a rough diagram:

image.png.c16169a165a5a607af4acedff0ea1675.png

The tie rods and the center link could be made with turnbuckles.

I'm not sure what I'd use for the idler arms; they'd likely be too short for a turnbuckle. I'd probably use the points above the A-arms where the steering servo mount posts screw in, although ideally they mount forward of the center link, to match the orientation of the steering knuckle. Maybe I'll have to fabricate a mount bracket. I'll wait until I have the front end retrofit kit installed and see what options I have once that's in place.

The idler arms should be parallel to each other at all times, and they should be at 90° to the center link at 0° steering angle.

Does anything like this exist, or am I on my own here?

Share this post


Link to post
Share on other sites

The front end conversion kit came! I had some time to install it today. It came with no specific instructions for adapting to Tamiya buggies (which I expected). But the eBay listing said that there were various builds documented online and all I'd have to do was search. I spent maybe half an hour, and didn't find anything. Lots of people modifying Grasshoppers, Hornets, etc., but none with this kit, and no pictures, videos, or instructions. The eBay listing had a couple annotated photos of someone else's build, and that was enough for me to figure it out.

Here's the result. You can also see the ESC, and you can kinda see the 8000mAh Ovonic 2S LiPo. Scroll down for several photos with detailed angles.

  

 

IMG_7535.jpeg.a50df7e83c05c9d7be56eb8983724e3a.jpeg

IMG_7536.jpeg.05fdaeaf449d90401880f6aaf01e77ca.jpeg 

IMG_7537.jpeg.d65633b707acf3dfbd826cf9bbf38035.jpeg

IMG_7540.jpeg.c214f450d213ed104e9cf8ce0a241548.jpeg

IMG_7539.jpeg.a32c36a63ccb38da0f012c5e16fbfe6b.jpeg

IMG_7538.jpeg.c19682b839db3db2fc8adfb3a8533d48.jpeg

 

And here you can see my new aluminum rear wheels (I have new front wheels too, but I don't have tires that fit them yet) and hubs, plus the new shocks. I'm still waiting for some rear end parts to come in.

IMG_7544.jpeg.88b3b14220f4e59ba02ae549fd41ed60.jpeg

IMG_7543.jpeg.efd9e8646de2f1a3d3168383d39f86e6.jpeg

 

And here's the rear end top view, with BZ motor:

IMG_7542.jpeg.830633a8180be9bd6653196ab395c0cc.jpeg

It's not done, of course. Still waiting on the 3GR and receiver, and I still need to figure out the steering as described above. Now I have clarity on what I'm working with, so I'll get started planning things soon!

IMG_7539.jpeg

IMG_7541.jpeg

IMG_7545.jpeg

  • Like 1

Share this post


Link to post
Share on other sites

Unfortunately, while the camber is now super stable, it's also super positive! I'm going to need to investigate replacing the upper control arms with adjustable turnbuckles!

Also, the shocks are too wide to connect to the intended point on the lower arms, and it clearancing the body there would have left extremely little material to hold everything together. Thankfully, the steering knuckle had an additional mount point, and there was enough hardware in the kit to mount them there. I think I like this geometry better anyway; more travel!

Share this post


Link to post
Share on other sites

I took some measurements of the modified result. Maybe they'll help someone here someday:

Upper control arm length: 50mm

Full width between steering arms (measured from the centers of the balls): 155mm

Expected length of tie rods (measured from the center of the ball on the steering arm to the pivot point of the lower control arm where it meets the chassis, and choosing the point along the pivot axis such that the tie rod would be parallel to the upper arm): 69mm

Opening where the servo arm goes: 55mm x 15mm (part of it is 12mm, but it can be widened if necessary

Spacing between the steering servo mount posts (from the centers of the screw holes where the servo mounts): 48mm

Fore-aft space between the servo mount posts and the front suspension bulkhead (basically clearance available for the servo+saver+horn): 19mm

Height of the front suspension bulkhead, plus the stock chassis to which it is mounted: 18mm

Thickness (fore-aft) of the front suspension bulkhead: 14mm

Space between shock towers: 37mm

Share this post


Link to post
Share on other sites

The 3GR is here!! I haven’t had a chance to play with it yet, but I paired it to the receiver and the steering servo works. I think I need to calibrate something for it to work with the ESC. 

Still working on building functional steering linkage around the giant LiPo.  

Share this post


Link to post
Share on other sites

ESC is working now -- but backwards. I don't _think_ I have the motor leads inverted. Going to read the 3GR manual and figure out how to reverse the throttle (because maybe it's already reversed for some reason?) before I just swap the leads. 

Share this post


Link to post
Share on other sites

Interesting project. I stopped modifiing my Grasshornet before I went into the aftermarket 3D print world and got a Tomahawk instead. I still love the Grasshornet though. 

 

I would save the nice BZ for the next project. As long as you are keeping the solid rear axle you will still have the caracteristic hopping and non existing gearing options. I dare to say it will be uncontrolable and the possibility to wreck it at an early point is good. With a Sport Tuned you are within sensible speeds. It's got enough power to drift and do donuts on oversteer and you need to practise throtle control in corners, so still challenging but on a realistic level. 

 

I run Kyosho Scorpion rear wheels on mine. On loose surface they are superb and they give extra damping because they are so soft. 

 

Check out ThunderDragoncy 's threads about his Ultra Hornet and Ultra G for good tips if you want to go IRS at the rear or simply modifiing to the next Level of the good old Hopper. His threads about modifiing the Thunder Dragon is also useful, if you are going that route later. One of the Dragons would be a good choice for your BZ BTW. 

 

Good luck :).

  • Like 1

Share this post


Link to post
Share on other sites

ESC is working correctly now. I ended up switching the leads to the motor — although I swear I had it right before! Weird. 

Anyhow, it’s all working now except the steering. Waiting on some parts, which should come in a couple days. Hopefully I can cobble something functional! It’s going to be awesome. 😁

Share this post


Link to post
Share on other sites
22 hours ago, Andreas W said:

I would save the nice BZ for the next project. As long as you are keeping the solid rear axle you will still have the caracteristic hopping and non existing gearing options. I dare to say it will be uncontrolable and the possibility to wreck it at an early point is good. With a Sport Tuned you are within sensible speeds. 

I don’t know if you noticed, but I’ve spent like $600 on this project. I’m way beyond sensible! At this point my objective is to make it ridiculous. My daughter will probably paint the body shell pink and purple with sparkly unicorns or something, which totally fits the plan.

If I wreck it, oh well — most likely I’d still be able to use the motor and all the electronics on something else that can handle it better. 

If I find that you’re right about the BZ having too much power, I’d probably just find a larger-diameter tire to increase the effective gear ratio.

Or maybe at that point I’d scrap the whole thing and buy an 8S X-Maxx! (Although then I think I’d be forced back to pistol-grip controller land, so perhaps not! 🤮)

Share this post


Link to post
Share on other sites
22 hours ago, Andreas W said:

I run Kyosho Scorpion rear wheels on mine. On loose surface they are superb and they give extra damping because they are so soft. 

Right now I have a fresh set of these: https://a.co/d/9axXH97

I’ll probably try something like these next: https://a.co/d/8T3S7pb (I have a set of 12mm hub adapters on hand.) They’re larger diameter and much better suited to a mixture of on- and off-road use. 

My front tires are the same style as the rears. I’d like to find something better for those too. Any suggestions?

Share this post


Link to post
Share on other sites

My suggestion for front tires are Schumacher cut Stagger low profile on 2" wheels (Kyosho Scorpion wheels with 850 bearings). Yellow compound for allround. I mostly run silver on mine and on the Tomahawk, but the Grasshornet will just griproll on astro or tarmac with silver, so for those conditions yellow are fine. I tried various 2,2 on the front, but it got so high then so it rolled a lot and was just frustrating. With the 2" low profiles everything suddenly went just fine. 

 

I have not tried it, but the Hornet rear wheels have the same diameter as the Scorpion, so you should be able to work a set of Scorpion tires on the Hornet rims when the spikes are worn down. That should not take long ;). These tires in medium compound grip really well on loose surface. That should in my opinion be a good performing and good looking solution. I would not use larger diameter than that on a chassis like this. It is already high geared and you only have the 18t pinion to choose. With that nuclear powerplant Lipo you have looooooong runtime. You should check the temperature on the endbell let's say every 5 minutes to start with.

 

600$ on this is... a lot. You could have got a Kyosho Turbo Scorpion with all carbon parts in the world for that and could have enjoyed the performance of the BZ straight away. But this is the hobby and part of the maturing process for body and mind B).

Share this post


Link to post
Share on other sites

To be fair, about half of that budget was on the Futaba 3GR-2.4G transmitter, which is everything I hoped it would be.

Also: with a functional radio set and ESC, I finally got a chance to try it out a little -- still no steering, but I pointed the tires straight and goosed the throttle, indoors on carpet. Holy cow! It wheelied so hard it flipped over. 🤣

  • Haha 1

Share this post


Link to post
Share on other sites

Okay, so the parts I ordered for the steering came Saturday. They are either not going to work or they’re going to require more modification than I was hoping. I haven’t decided yet. I knew when I ordered that it was questionable. 

So anyway, the steering was the only thing holding up a proper test drive, so yesterday I decided to put it together with the stock steering setup, but using the Hyperion micro servo. Had to cobble the mounts, and I had to use a non-servo-saver horn since I can’t seem to find a servo saver with A15T splines. It worked, ish. Had to extend the toe links as far as they would go to get a remotely reasonable toe angle. Max steering angle to the right was pretty limited, but it was functional enough to try it out. 

Anyway, this was about 5pm; light was fading. So I grabbed my girls (solo parenting today), got them suited up for cold (it was about 28F here today), and out we went. 

I hopped it around in the grass for a bit, then up to the road (residential dead end, no traffic) for some speed runs. Holy badword, it’s FAST! Just a guess — 28-30mph? No idea. I made sure the kids knew to stay out of the street, and I sent it zooming down the road maybe 200 yards, which felt like it took two seconds. Turned it around for a high-speed flyby and sent it. 

Meanwhile my four-year-old daughter had decided she wants to make a “tunnel” for the car with her legs and has gone into the street and made a wide stance. As the car is approaching at max speed, she says “dad, drive it through this tunnel!” Which, by the time the sound reaches my ears and I process it, the car has already slammed into her foot. As I turn my head, I see her, in the middle of the road, get flipped off her feet like a cartoon. Thankfully, she was wearing thick winter boots, a thick hat, and leather mittens, so injuries were limited to a minor nosebleed. I had my other daughter gather up the car, and we all went inside to take care of the kid.

I’m pretty sure the car hit her tire-first, because the servo horn snapped off, and one of the tie rods stripped itself out of the ball end. So, back at square one on the steering. 😅

It was a ton of fun for about two minutes!!

Share this post


Link to post
Share on other sites
11 hours ago, Andreas W said:

My suggestion for front tires are Schumacher cut Stagger low profile on 2" wheels (Kyosho Scorpion wheels with 850 bearings). Yellow compound for allround. I mostly run silver on mine and on the Tomahawk, but the Grasshornet will just griproll on astro or tarmac with silver, so for those conditions yellow are fine. I tried various 2,2 on the front, but it got so high then so it rolled a lot and was just frustrating. With the 2" low profiles everything suddenly went just fine. 

I have not tried it, but the Hornet rear wheels have the same diameter as the Scorpion, so you should be able to work a set of Scorpion tires on the Hornet rims when the spikes are worn down. That should not take long ;). These tires in medium compound grip really well on loose surface. That should in my opinion be a good performing and good looking solution.

Thanks. I looked up the Scorpion wheel, and it says it's just a friction mount; not 12mm and not the like hub on my Hornet (does that have a more specific name?) either. Is that what you have? What hub surface do you use? Any specific tricks to mate it up? Any issues with slippage?

Quote

I would not use larger diameter than that on a chassis like this. It is already high geared and you only have the 18t pinion to choose. With that nuclear powerplant Lipo you have looooooong runtime. You should check the temperature on the endbell let's say every 5 minutes to start with.

You said that the BZ would have too much power and it would be unmanageable. Tire diameter is an effective way to manipulate gear ratios; a larger tire would mean less torque at the contact patch. You'd get more top speed and less tire slip under acceleration. Seems like a good trade, so why not?

Endbell is the end of the motor where the connections come out, right? Sorry, I'm still learning some RC-specific terminology. :)

Quote

600$ on this is... a lot. You could have got a Kyosho Turbo Scorpion with all carbon parts in the world for that and could have enjoyed the performance of the BZ straight away. But this is the hobby and part of the maturing process for body and mind B).

Yeah, but it wouldn't be the (Super) Hornet of my childhood memories, so it's not the same. That's why I'm willing to spend relatively stupid amounts of money on this.

If I'm buying something new, I'm going all out -- definitely 4WD, maybe bigger scale, 4S or more, brushless....

Share this post


Link to post
Share on other sites

The Scorpion wheels use a serrated friction hub instead of the Tamiya one. I got one with my Tomahawk and drilled it to fit. The neater solution is to get the Ampro part from Shapeways though. That looks like the Tamiya part, but fits the Scorpion wheels like a glowe. 

 

In my answer I assumed that you were going to keep the solid rear axle. If you are going the ThunderDragoncy-route with Dragon rear suspension things change a little. Then you do'nt need the balloon rear tires, because now you got a proper working rear suspension. You also got an adjustable motor mount, so you can choose different pinion-sizes according to what you want to acchieve. For the proper looks I then would have got the 2,2 Wild One wheels from JC Racing Products (like Cy is riding) and some Schumacher tires according to preference. 

 

The endbell is where the motor axle and axle bushing is attached (and the wires, yes). It's fully correct that larger diameter will decrease the torque towards the surface. In your case (given that you run the solid rear axle) i think the BZ has so much torque that you end up with even more top speed and lots of heat. 

 

As I said earlier: The Sport Tuned is the sweet spot for a solid axle car according to my experience. Powerful enough to be entertaining and fast enough so you need to practise throtle control. Already on NIHM it is too fast to be driven with digital throtle, like we did in the childhood with Nicads and standard silvercan^_^. In my head perfect for grownups, who want it faster and a little more challenging than bitd. Stick the control in the hands of an unexperienced child and you are garanteed endless rolling.

 

With a Dragon rear suspension the BZ should be fine for grownups. 

Share this post


Link to post
Share on other sites

SuperHornet runs 2.0” rear wheels, same molding as Fox/WildOne just in orange ABS. 

2” rear tyres easily sourced from Hotshot oval blocks, Supershot pin spikes, rere WildOneOffroader & NovaFox. 

Latest fanciest 2.0” tyre supply would be off 2022 Kyosho Optima Mid; or maybe 2019’s Turbo Optima might’ve used the same rubber too. 

Schumacher still makes some 2.0s in their “C.A.T” range but I find it hard to differentiate which are 2.0/2.1/2.2”. My schuey-stockist LHS never have enough range in stock at any one time to let me properly compare. 

Share this post


Link to post
Share on other sites
On 11/12/2022 at 7:27 AM, FromageTheDog said:

To push back a little on the "premium priced top end" characterization, I think the prevalence of cheap Chinese radio gear forced Futaba to introduce less eye-wateringly priced gear that still maintains their high standards of quality.  I'm thinking in particular of the FHSS-based gear like the 3PV, which while more expensive than the FlySky equivalent, is still quite affordable and comes with the benefit of Futaba peace-of-mind...

OP wanted sticks :P hence his search for 3GR. 

Downunder cheapest stick Futaba I’ve held is 4YWD for around A$240; 3PV is about A$230. 

Just noticed arrival of T6L in either Mode 1 or 2... priced at A$150ish. Could be decent entry level Futaba for anybody wanting sticks going forward.

Flysky is like A$60ish for T4B or GT2B.

KO is making some interesting gear lately, decently priced vs Sanwa/Futaba too... have you seen their MC8? :D A$150 for 6-channel!

image.jpeg.431bd141954ed43984d0f4a02bc581fa.jpeg

 

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...