Kyosho Big Brute, Ultima XL and Turbo Raider - Back Into RC

[Snaab9-2]

Hello everyone. My name is Brian and I am from Delaware. I have been looking around at various forums and a lot of you guys seem to know a lot about Kyosho cars! I have been out of the hobby for 20 + years but am looking to get back in. When I was a teen, I had a Big Brute, a Turbo Raider and my dad had a Turbo Ultima Pro XL that was bought lightly used and was set up by a racer (which he recently gave to me). They have all been sitting in my dad’s basement (I even have the original boxes and extra parts for the Brute and Raider) and I am going to work on getting them back in running condition. I haven’t decided which one I am going to start with for sure, but I am leaning towards either the Raider or the Ultima as the Big Brute’s tires look like they almost melted right off of the rims and I have the need for some speed…. and while a lot of fun, I remember the Brute being a slow and sloppy mess. Also, the Raider sounds appealing as my son is 8 and he could have some fun with it…. though maybe I just get it running for him and mess around with the Ultima… decisions decisions….

Things have changed SO MUCH in the past 20 years and I am reading up to try to understand what direction I want to go. I think the old NICD batteries are probably toast but I figure I will try to charge a few of them to see if I can at least use them to test the cars out. After that, I think I will invest in a LIPO compatible charger and get a 2C LIPO battery (probably a shorty assuming the measurements work out as the Ultima’s battery slot is set up for a NICD with 5 cells in a row and one on the top in the middle). I am a little worried as I don’t think my old electronic ESC’s will not cut off when the voltage gets low, but I will play it safe and not let them run down too far/I suppose use a volt meter or possibly get an alarm? I really like the idea of the fast charge times and about 3 times the run time of the old 1,200 milliamp batteries!

I really want to save up and go brushless but I still have so much to learn. It is my understanding that the Ultima should have strong enough gearing to go brushless but the Raider…. It sounds iffy. That is too bad as I really would like to get that thing to move as I have a lot of memories with that car but it never was fast enough. A shame as it is so light! I think I put a 13 turn engine in it (maybe 15, have to check) but even then it was much slower than the Ultima (it had a pretty hot motor too). It sounds like the gearing in the Raider is not set up for speed and I believe the car can only run a 14 or 15 tooth pinion gear (are there more options?). I don’t recall what mine has in it. This post said that it may be possible to use a different pinion but I am lost.

http://fun-with-rc.blogspot.com/2013/06/kyosho-raider-restoration-part-1.html?showComment=1421955285125#c3094436365816710945
Here is what the manual shows:
http://2.bp.blogspot.com/-7ZkeMRL45Lo/UbPxykWGt7I/AAAAAAAAA2Q/I0ALEn4LQcM/s1600/IMG_1771-800.JPG

If I do go brushless, I am worried about the extra torque on the gears. As I understand it, the higher kv engines have less torque at a given voltage, so would I be better served to get one with a high kv rating (like 4,000+ or even 5,000+?) not only for less stress on the box but also because of the really short gearing of the Raider? Would this be a ways to get the Raider to really move while still giving the gearbox a shot of making it?
I look forward to learning from and being part of the group!














http://rs76.pbsrc.com/albums/j34/BrianC302/get-attachment_zpsvy9bggqf.jpg~320x480[img]http://rs76.pbsrc.com/albums/j34/BrianC302/get-attachment_zpsvy9bggqf.jpg~320x480[/img]

[Coelacanth]

Welcome to the forum, nice cars! I like that Turbo Raider, actually. You're in good hands here but yes, there's a bit of a "re-learning curve" when it comes to modern electronics. It's not possible to make a single post to answer all your questions and teach you everything you need to know about modern electronics, but I made the same switch a few years ago with my Kyosho cars...most of which are modded & modernized.

You can get decent, inexpensive ESC/motor/program card combos by EZRun, Leopard Toro and others in various power ratings. For the buggies, you'll want ESCs with 30A - 60A output ratings and maybe a 12T for the Ultima and from a 13.5T - 17T for the Raider. A combo similar to the specs I chose for my OptiMutt project would probably work well for your Ultima (linked in my signature). You can dial down the punch (torque upon acceleration) when you punch the trigger to reduce stress on the gears. EZRun makes combos in many motor ratings; I probably wouldn't go lower than 13.5T for the Raider. The ESCs can be programmed for low voltage cutoff.

A cheap but good radio system is the FlySky GT3B series. One transmitter can be programmed to control up to 10 cars, you just need to buy extra receivers and steering servos for each additional car, but "fun grade" ones aren't expensive, either. You don't need to buy $50 servos for those cars. One FlySky GT3B radio is under $40 at HobbyPartz.com, last time I checked, and their shipping rates are among the best.

You'll want to upgrade to LiPo batteries too; they make a couple models that have almost the same size & shape as the old NiCads; GensAce makes a decent unit; this is the one I use:

http://www.hobbypartz.com/98p-25c-4000-2s1p-hardcase-direct.html

You'll also need an updated battery charger for those, I use an iMax B6, but there are many models that do a similar thing. You want a charger that can balance charge, storage charge and discharge, if possible. You don't want LiPos to be over-discharged, and you don't want to store them with a full charge, either.

That's a lot of info for one post, but don't worry...narrow down your questions to more specific stuff as you get working on your restorations, and there'll be lots of advice for you here.

[DePingus]

Gold shocks...[drool]

Welcome aboard! I'm in the same boat. I found my way here just recently when I started a rebuild of my old Ultima II. You'll find the users here are very knowledgeable and friendly.

The biggest issue I had with my build was the tires. I needed new ones and tires in these sizes are very hard to find and expensive when you do. So I decided to get modern wheels, but modern wheels don't fit the front axles. So I had to get new axles, wheels, and finally the new tires...putting me way over budget! Now my stock MSC, motor, and connectors get hot rather quickly trying to roll these bigger tires...so the upgrades continue!

I think the biggest take away for me was learning (the hard way) that modernizing an old car, is not really cheaper than starting with a new one. That, and the whole RTR phenomenon...

[Snaab9-2]

Thanks for the information/replies!

Wow, Coelacanth, your car looks amazing! Very nice! What I still don't understand yet is why would I go with a higher turn (slower spinning) motor on the Raider than the Ultima? If the gearning on the Raider is shorter (it doesn't go as fast per RPM), wouldn't it be better to have a high reving engine in it? Also, how is the sweet spot determined? I will run a 2 cell LIPO but what would the disadvantage of running say a 10 turn brushless motor VS a 12 or a 13.5 brusheless? I suppose there is more of a disadvantage that just more speed. What would be a good engine for the Big Brute? I suppose something really torquy closer to teh 17 turn end of the specturm? Also, why would I need to get a new radio? If the old ones work, is there a reason why I couldn't use them with the rest of my planned setup? If they don't work, it is nice to know that a new one is pretty cheap! I am sure there are good reasons for yoru answers as you know a heck of a lot more than I do, I am just trying to make sense of it!

Depingus, how much did the new axles/wheels tires and such cost? Are you running on the stock old MSC and brushed motor? I think the front tires on both cars are OK for now but the backs are flat spotted from sitting so long. I have another set that looks OK (they were not installed on a car). It looks like I can at least get things rolling for now.

The weird thing about the Ultima is that it's batter is 5 cells in a row and 1 on top so the space is too short for a normal 6 cell NICD pack. There isn't enough room to fit a regular sized pack the way the older is situated now (servo is on one end and the speed controler on the other). Does anyone know if a shorty LIPO is the same size as 5 cells in length? I suppose I just need to measure it. I am not sure what the 5 cell with 1 on top setup is called.... was this common back in the day? I was thinking of something like this:
http://www.hobbyking.com/hobbyking/store/__23134__Turnigy_nano_tech_Shorty_4200mah_2S2P_65_130C_Hardcase_Lipo_Pack_ROAR_APPROVED_.html
and they make cheap foam inserts so that I could use it on my raider too/so it wouldn't slide around.

[notarex]

Those turnigy shorties are decent for the price, I bought a few when I started getting back onto RC. I think the recommendations of a "slower" motor are based on the fact that the Ultima was designed stronger to handle a faster Mod motor. The raider is more of an entry level racer, so you could take your chances but I think a 17.5 on lipo would be plenty quick. Any more and you may overwhelm the suspension and drivetrain. I'm still amazed at the kind of power brushless/lipo has vs the old brushed/nimh. Coelacanth gives sage advice regarding lipo chargers, make sure you get one that ticks all the boxes, lipos require a bit more care than the nicd/nimh we were used to.

[Coelacanth]

Thanks for the information/replies!

What I still don't understand yet is why would I go with a higher turn (slower spinning) motor on the Raider than the Ultima?

Generally speaking, the lower number of turns in a brushless motor, the more powerful it is. So I figure the Raider is less able to handle the power than the Ultima. BL motors also have a kV spec, which is how many thousand RPM per volt. So for example, a 3500 kV motor will spin close to 30,000 RPM on a fully charged 8.4V LiPo battery. Back in the day, only the hottest 4-minute motors got this high. Also keep in mind BL motors put out much more torque, that 30,000 RPM comes on almost instantly (if programmed by the ESC that way), unlike the brushed motors of the past. That can be pretty harmful to old gearboxes without modern slipper gears installed.

I think I learned a while back that a 17.5T BL motor would be more or less comparable to a stock 540-can motor back in the day; a 13.5T would be a pretty juicy upgrade, but with the ESC programmed properly with regards to punch, not too much that it would blow up your vintage gears, at least in inferior cars like the Raider. The racer-grade cars like a hopped up Ultima can handle a bit more than that, but honestly, below 11T or so and the car gets pretty uncontrollable for anything but straight-line speed-runs.

If you can let me know a car's transmission gear ratio, spur gear size and the diameter of the tires, I created a spreadsheet that can calculate a theoretical optimal pinion gear, give or take a tooth.

[Snaab9-2]

Thanks for the information/replies!

What I still don't understand yet is why would I go with a higher turn (slower spinning) motor on the Raider than the Ultima?

Generally speaking, the lower number of turns in a brushless motor, the more powerful it is. So I figure the Raider is less able to handle the power than the Ultima. BL motors also have a kV spec, which is how many thousand RPM per volt. So for example, a 3500 kV motor will spin close to 30,000 RPM on a fully charged 8.4V LiPo battery. Back in the day, only the hottest 4-minute motors got this high. Also keep in mind BL motors put out much more torque, that 30,000 RPM comes on almost instantly (if programmed by the ESC that way), unlike the brushed motors of the past. That can be pretty harmful to old gearboxes without modern slipper gears installed.

I think I learned a while back that a 17.5T BL motor would be more or less comparable to a stock 540-can motor back in the day; a 13.5T would be a pretty juicy upgrade, but with the ESC programmed properly with regards to punch, not too much that it would blow up your vintage gears, at least in inferior cars like the Raider. The racer-grade cars like a hopped up Ultima can handle a bit more than that, but honestly, below 11T or so and the car gets pretty uncontrollable for anything but straight-line speed-runs.

If you can let me know a car's transmission gear ratio, spur gear size and the diameter of the tires, I created a spreadsheet that can calculate a theoretical optimal pinion gear, give or take a tooth.

Yeah, I guess that is a really valid point that the Raider would be really unstable at high speeds.... I do recall it being much more darty and harder to drive fast than the Ultima. Plus, I don't think I really have a handle on just how fast these brushless motors are!

Being the car geek I am, I was looking at it that if the lower turn motors make less torque than the higher reving ones, it would make less stress on the gear box. Much like a 2.0 L engine with 240 hp (at 8,000 rpms) and 150 lb-ft of torque works just fine with the gearbox in a S2000 but if you were to take an old V8 from the 80s that made 240 hp (at 4,000 rpms) and 350 lb-ft of torque it would likely be too much for the trans of a S2000. Is is torque (the max twisting force) not HP that determins the make failure point of a trans. By reving higher, even though the engine in the S2000 is making a fairly small amount of power (torque), by spinning fast it is able to make good HP or power over time). I was carrying this thought process over to RC cars. I figured that the slower spinning engine with more torque (force applied to the gears over shorter period of time) would be harder on the gear box. The faster spinning would would apply less force to the gears. That being said, I could almost visualize the gears in the Raider spinning too fast and just coming apart! And now that I know the ESC can make the power come on slower, I suppose it makes sense.

As for the gear rations, I appreciate the offer. I will have to look into that!

[Coelacanth]

What would be a good engine for the Big Brute? I suppose something really torquy closer to teh 17 turn end of the specturm? Also, why would I need to get a new radio? If the old ones work, is there a reason why I couldn't use them with the rest of my planned setup?

I'll answer these separately; well, I'll let someone else answer the Big Brute question, I don't have any monster trucks so I don't know what I'd recommend. I'll let the truck experts tackle that one.

As for the radio, the old radios only worked on a narrow range of frequencies, and you were always making sure you were using a different frequency than your mates, with the crystals. Radios were also very glitchy with some motors, interference-wise. Lastly, the range wasn't very far. With a modern 2.4 GHz radio, you just turn it on, bind it to the receiver, and it automatically uses a unique frequency that won't mess with your mates' radios. The range is WAY farther and the antenna is nice and short, not some foot-long tube with another 4 inches of receiver wire that you gotta manage somehow. They also have a lot of features like adjustable servo endpoints (easy to increase/reduce amount of steering, or if you need to adjust if your car steers too much one way but not the other, which is better than just adjusting the trim)...and for $39.99 for a transmitter & receiver, you can't go wrong...just add servos!

[DePingus]

Depingus, how much did the new axles/wheels tires and such cost? Are you running on the stock old MSC and brushed motor? I think the front tires on both cars are OK for now but the backs are flat spotted from sitting so long. I have another set that looks OK (they were not installed on a car). It looks like I can at least get things rolling for now.

Let's see....

Pro-Line Dirt Hawg I Rear Tires $13
Pro-Line Dirt Hawg III Front Tires $11
Tamiya Dish Wheels Rear $7
Tamiya Dish Wheels Front $6
Tire Glue (can't forget that!) $8
CRP 1712 Front Axles $9
Kyosho Ball Ends (I broke one) $7

Nothing is really expensive, but I feel like I've been nickle and diming myself to death!

I am currently running the stock mechanical speed control (you know, the one that makes you chase the car when the battery gets low) and stock Le Mans 05 brushed motor. The new NiCD 1500mah battery I have lasts about 4 minutes and in that time the old motor connectors get hot enough to stick to the paint inside the body. I'm also still using my original Futaba radio.

I have on order a 2S 5000mah LiPo battery, charger/balancer, ESC, low voltage alarm, XT60 connectors, 15T brushed motor, 12 tooth pinion, gear grease, and a set of ball bearings. Hopefully that should get me up to speed with these bigger wheels. Check out my build thread for pics. You can see just how much bigger these 2.2" tires are. http://www.rc10talk.com/viewtopic.php?f=30&t=37296

I decided to stick with a brushed setup as its cheaper and I shouldn't have to worry about tearing up the gears. I'll probably get a modern car in the near future to go brushless and semi-retire this old gal.

If I were you, I would not run those never-been-used original tires. They're hard to come by and pricey. The original rear tires (Kyosho OT-66) go for about $70 on ebay; repros are about $30. And those knobbies will dissolve quickly on brushless speed. If you ever want to go back to full stock and turn it into a shelf queen, you'll want them back. Or, if you're not interested in returned to stock, sell them for some cash. Once you use them up, you'll have to tackle the tire issue anyways.

[TM Ru22311]

Hello and welcome to the forums

As a collector of these vintage buggies, I have to side with DePingus on this one. You have to remember, these buggies weren't meant to run at the speeds you will be getting from a modern electric system. As Coelacanth described, it is not impossible, but probably not practical. It can be done (and has been by many) but there are issues that you will face that you wouldn't if you got a modern buggy. The tire issue is probably the first thing you want to address, so that you will be able to easily buy new tires whenever you need them.

For what these vintage rides are selling for now a day, you could easily sell them and get something more "Updated" to run. The 2014 Scorpion would be a great choice because it has that vintage look and feel, but the suspension and gearbox has been modernized to accommodate a BL/Lipo setup without problems. I'm not trying to steer you away from your plan, but just want you to consider this before dumping a lot of money into the project. I've thought about it more than once, but decided to restore them back to their glory to admire from a shelf :/

[Snaab9-2]

Depingus, how much did the new axles/wheels tires and such cost? Are you running on the stock old MSC and brushed motor? I think the front tires on both cars are OK for now but the backs are flat spotted from sitting so long. I have another set that looks OK (they were not installed on a car). It looks like I can at least get things rolling for now.

Let's see....

Pro-Line Dirt Hawg I Rear Tires $13
Pro-Line Dirt Hawg III Front Tires $11
Tamiya Dish Wheels Rear $7
Tamiya Dish Wheels Front $6
Tire Glue (can't forget that!) $8
CRP 1712 Front Axles $9
Kyosho Ball Ends (I broke one) $7

Nothing is really expensive, but I feel like I've been nickle and diming myself to death!

I am currently running the stock mechanical speed control (you know, the one that makes you chase the car when the battery gets low) and stock Le Mans 05 brushed motor. The new NiCD 1500mah battery I have lasts about 4 minutes and in that time the old motor connectors get hot enough to stick to the paint inside the body. I'm also still using my original Futaba radio.

I have on order a 2S 5000mah LiPo battery, charger/balancer, ESC, low voltage alarm, XT60 connectors, 15T brushed motor, 12 tooth pinion, gear grease, and a set of ball bearings. Hopefully that should get me up to speed with these bigger wheels. Check out my build thread for pics. You can see just how much bigger these 2.2" tires are. http://www.rc10talk.com/viewtopic.php?f=30&t=37296

I decided to stick with a brushed setup as its cheaper and I shouldn't have to worry about tearing up the gears. I'll probably get a modern car in the near future to go brushless and semi-retire this old gal.

If I were you, I would not run those never-been-used original tires. They're hard to come by and pricey. The original rear tires (Kyosho OT-66) go for about $70 on ebay; repros are about $30. And those knobbies will dissolve quickly on brushless speed. If you ever want to go back to full stock and turn it into a shelf queen, you'll want them back. Or, if you're not interested in returned to stock, sell them for some cash. Once you use them up, you'll have to tackle the tire issue anyways.

Thanks for the info, really appreciate it! All of this is helping me get up to speed.

Oh, those tires just were not on a car.... they are not in bad condition but not new.

[Snaab9-2]

Got the Ultima working today..... put a motor in it and 1 of the batteries still hold a charge 25 years later! It only ran for a few min but ripped pretty good for some drifting fun. Cannot wait for some new LIPOs in it! Do the gears need any lube or do they run dry?

The Raiders motor seems to be toast but other than that it is ready to go too!

The Ultima run so well....i think it had some mods to it. Can a anyone tell from the pic above if it looks different than stock? I think the frame (pan) may be carbon and the steering rack looks really fancy.

[Snaab9-2]

Thanks for the information/replies!

What I still don't understand yet is why would I go with a higher turn (slower spinning) motor on the Raider than the Ultima?

If you can let me know a car's transmission gear ratio, spur gear size and the diameter of the tires, I created a spreadsheet that can calculate a theoretical optimal pinion gear, give or take a tooth.

Best i can tell it is a 22 tooth pinion, the big gear has I think 63ish teeth and the wheels say 2.0x1.6 and arw made by Losi but measure closer to 2.25 tall with a ruler. Is that enough info? I may switch to 2.2 inch wheels later. Thanks

[Coelacanth]

Thanks for the information/replies!

What I still don't understand yet is why would I go with a higher turn (slower spinning) motor on the Raider than the Ultima?

If you can let me know a car's transmission gear ratio, spur gear size and the diameter of the tires, I created a spreadsheet that can calculate a theoretical optimal pinion gear, give or take a tooth.

Best i can tell it is a 22 tooth pinion, the big gear has I think 63ish teeth and the wheels say 2.0x1.6 and arw made by Losi but measure closer to 2.25 tall with a ruler. Is that enough info? I may switch to 2.2 inch wheels later. Thanks

I need your tire outside diameter, not the wheel diameter. It should be somewhere between 80 and 90mm, over 3" tall. Please measure the exact height of a rear tire including spikes, if applicable. That will give me all the inputs for my spreadsheet to calculate an optimal pinion gear to mate with that 63T spur gear, give or take a tooth. Thanks!

[Snaab9-2]

Oh yes, I guess that would make sense. Very close to 80 mm....maybe slightly larger if they balloon out when spinning. One set are road tires and the other are low profile spikes. Both virtually identical in size.