Kyosho Optima Mid Custom Rebuild

[James.S]

2 minutes ago, Drapes86 said:

There's only a handful of bits left in the box so I can't be too far off that stage! If she does run then it will have to be a kitchen floor test drive I'm afraid (all of the belt covers protecting the drive mechanism are off until I get the adhesive tape).

 

Have you got any thoughts on this ESC and BM combo?

https://www.modelsport.co.uk/hobbywing-ezrun-combo-max10-3652sl-4000kv-brushless-motor/rc-car-products/420923

 

Awesome! And ah yes, of course. Probably better off waiting for the tape to arrive & then give it a proper run outdoors. That also prevents any premature breakages from crashing into a very solid kitchen unit... trust me, it's easily done 😂

 

That esc & motor combo looks good to me. But just know that with 4000kv's you're gonna be getting a pretty high top speed if you plan to run it on 3s. On 2s it will probably be tame enough (30-35mph ish) but with 3 cells it may get a bit uncontrollable. You may be better off with this combo: https://www.modelsport.co.uk/index.php?product_id=420922 That one has a 3300kv motor instead which will give you more punchy acceleration with less top end. It's all about personal preference though... maybe you want a speed demon  

 

[Drapes86]

5 minutes ago, James RC said:

 

Awesome! And ah yes, of course. Probably better off waiting for the tape to arrive & then give it a proper run outdoors. That also prevents any premature breakages from crashing into a very solid kitchen unit... trust me, it's easily done 😂

 

That esc & motor combo looks good to me. But just know that with 4000kv's you're gonna be getting a pretty high top speed if you plan to run it on 3s. On 2s it will probably be tame enough (30-35mph ish) but with 3 cells it may get a bit uncontrollable. You may be better off with this combo: https://www.modelsport.co.uk/index.php?product_id=420922 That one has a 3300kv motor instead which will give you more punchy acceleration with less top end. It's all about personal preference though... maybe you want a speed demon  

 

Good shout, I will get the lower kv motor for sure. Having only driven Tyco cars when I was a kid, I'll probably smash it into a thousand tiny pieces on the first run if I'm not careful! 😂

 

When you say 2's and 3's, are you referring to cells in a LiPo battery? 🙈

I have ordered a Traxxas NiMh battery just to get her going in the first place but will look into battery tech down the line. Presumably everything works with either NiMh or LiPo and it's about matching the right Voltage and Capacity for the motor...?

[Ag100]

39 minutes ago, Drapes86 said:

Here's the progress at the end of day one, and she's looking good if I do say so myself! Not everything is perfect; a bit of rust here and there, a couple of screws turn in the holes when seated all the way down,  the suspension feels a little gritty, but nothing major from what I can tell...

I'm still going to install the original motor, servos and receivers to see what works and what doesn't, but that's only whilst I decide on what new kit is going to go in to bring her up to the 21st century! 😀

Coming together nicely, really like the look of the older buggy’s, love the wheels too, really missing mine now!

[James.S]

8 minutes ago, Drapes86 said:

Good shout, I will get the lower kv motor for sure. Having only driven Tyco cars when I was a kid, I'll probably smash it into a thousand tiny pieces on the first run if I'm not careful! 😂

 

When you say 2's and 3's, are you referring to cells in a LiPo battery? 🙈

I have ordered a Traxxas NiMh battery just to get her going in the first place but will look into battery tech down the line. Presumably everything works with either NiMh or LiPo and it's about matching the right Voltage and Capacity for the motor...?

 

I think that's a wise decision for sure. Either way this kind of brushless setup will feel A LOT different from driving those tyco cars back in the day 😋 

 

Yes, 2s meaning 2 cells (7.4v) and 3s - 3 cells (11.1v). There is a significant power increase when using a lipo over nimh, but to be honest I think you've made a good choice there. Getting acquainted with the car & getting used to driving it will be easier when using a less powerful battery.

And yeah that motor & esc combo can take a maximum of 3 cell lipo/9 cell nimh, so you're all good 

[bertberr]

That's far too much motor for an old vintage buggy.  I have that exact same same can in one of my 1/10 SCT's, and its pokey in that.  It's a 4-pole 4000KV can - apart from being almost uncontrollable even on a decent 2S, the torque will shred the Idler gear, most prob the diffs too, and likely the 48dp spur/pinny too.  These cars were running 1200mah 7.2 NiCd back in the day, with motors around 12-19 turn depending on track.  Furthermore your 7.2v nimh you've bought is not going to supply the juice, at least not for long, that a hungry 4-pole can like that will demand.

 

You haven't said what your intentions are for the car once its finished?  If shelf queen, then just pop the 240 ST back in.  If the 240 is healthy, then pair that with a 1060 and use and enjoy for what it is - a 30 year old classic buggy, with either impossible or very hard to source / very expensive spare parts.  If you're really intent on ringing its neck and must have BL,  then throw in a sensored 2-pole Quicrun or comparable can, around 2800-3300KV, so 13.5 or 10.5T (max), and a 60amp esc (plenty capable in one of these), and enjoy.

[Drapes86]

1 hour ago, bertberr said:

That's far too much motor for an old vintage buggy.  I have that exact same same can in one of my 1/10 SCT's, and its pokey in that.  It's a 4-pole 4000KV can - apart from being almost uncontrollable even on a decent 2S, the torque will shred the Idler gear, most prob the diffs too, and likely the 48dp spur/pinny too.  These cars were running 1200mah 7.2 NiCd back in the day, with motors around 12-19 turn depending on track.  Furthermore your 7.2v nimh you've bought is not going to supply the juice, at least not for long, that a hungry 4-pole can like that will demand.

 

You haven't said what your intentions are for the car once its finished?  If shelf queen, then just pop the 240 ST back in.  If the 240 is healthy, then pair that with a 1060 and use and enjoy for what it is - a 30 year old classic buggy, with either impossible or very hard to source / very expensive spare parts.  If you're really intent on ringing its neck and must have BL,  then throw in a sensored 2-pole Quicrun or comparable can, around 2800-3300KV, so 13.5 or 10.5T (max), and a 60amp esc (plenty capable in one of these),

I don't really know my intentions for it yet... 2 days ago I'd never even heard of Kyosho, let alone knew that the battered old car in my garage was one!

 

I'm an engineer by trade, so at the moment I'm just enjoying learning about and rebuilding it. Once completed though, I will definitely use it in some capacity but I also want to look after it... I couldn't bare to see the look on my kids faces if when I tell them it's for looking at only! 😂

 

What do you mean by pairing it with a 1060? I definitely want to rebuild it within it's capability, so I clearly need to give this some more thought...

[bertberr]

Hobbywing 1060 esc, can take a brushed can down to 12 turn on 2S.  Yes, please do give it some further thought before diving in and throwing money at electronics.  From memory, the chassis on these LWB cars are designed for saddle packs, so you could go with two shorty 2S packs, one each side.  You defo don't need 3S for one of these.  These are not 'bashers' in the modern sense of the term - you can't treat em like a Slash or Granite and expect not to break anything.  But you can still have a lot of fun with them, but remember these things are tiny and weigh very little (compared to modern 1/10 trucks), so you really don't need crazy power.  I have two SWB versions, and even with 'just' a 13.5T on 2S, I've never felt the car was slow. 

 

There is some good info in the Kyosho section of tamiyaclub.com and also over at RC10talk.  Oople have some good older posts too.  BTW, those later pics you posted show what looks to be a REALLY nice unabused example of one of these - rare to find these days, so please do slow down, take a breath, read up as much as you can about these amazing old buggies, and enjoy the journey. 

[Drapes86]

Not too much of an update today I'm afraid... I have however inspected the old Le Mans 240ST motor, and it looks in really good condition from what I can tell. The more I get into the car, the less evidence of any hard use I can find!

 

The brushes don't appear to have ever been replaced and they are almost new. I have ordered some new replacement bushes nonetheless because of tarnishing on the leads.

 

I'm also going to buy a new transmitter and receiver combo irrespective of whether the old Techniplus "acoms" system works or not - the original aerial lead is damaged and I don't hold out much hope except for testing at close range... I think I want the Absima CR3P AGHDS transmitter which comes with a R3WP receiver.

 

My question is: are the Acoms IC AS-7 servos plug and play with the R3WP receiver?

 

Thanks in advance! 👍

[Ag100]

I’m not sure on the servo front actually, O guess or should work, you can always try it, servos are pretty cheap if not. I’m sure someone else might be able to say definitely 

[Drapes86]

13 minutes ago, Ag100 said:

I’m not sure on the servo front actually, O guess or should work, you can always try it, servos are pretty cheap if not. I’m sure someone else might be able to say definitely 

The block of 12 pins in the receiver are there for 4 x connectors to sit, and the 3 pins of the receiver and the servo connector do appear to be the right pitch to fit... so I guess there really is one way to find out for sure?

 

Looking at servos online, the connectors look the same, so I guess these have remained consistent over the years.

 

I'm going to wait until the rebuild is complete and the car is tested, then the final pieces of the puzzle will be the transmitter and a new body kit 👌

[Dan_Q]

Great car, hope you enjoy the build and drive once complete

I ran one of these back in the early 90's, got it second hand from LOOT, it was old and undesirable at the time and I couldn't get parts for it even then! Mine is also a composite chassis and deck, I believe mine is original but cant be 100%- maybe we have later ones as someone has suggested.

I ran mine on 1700SCE nicads, and the 240 ST motor gave it a good turn of speed! I say try a modern ESC with the stock motor and decide from there- I did actually burn out the MSC on mine eventually, which resigned it to retirement and i went back to using my mardave mini!

All the best, I'll keep an eye on this one 😍

Edited November 23, 2020 by Dan_Q

[Drapes86]

2 minutes ago, Dan_Q said:

Great car, hope you enjoy the build and drive once complete

I ran one of these back in the early 90's, got it second hand from LOOT, it was old and undesirable at the time and I couldn't get parts for it even then! Mine is also a composite chassis and deck, I believe mine is original but cant be 100%- maybe we have later ones as someone has suggested.

I ran mine on 1700SCE nicads, and the 240 ST motor gave it a good turn of speed! I say try a modern ESC with the stock motor ad decide from there I did actually burn out the MSC on mine eventually, which resigned it to retirement and i went back to using my mardave mini!

All the best, I'll keep an eye on this one 😍

Thanks Dan! I'm rebuilding it to the exact spec I found it to establish what works and what doesn't and then go from there. During disassembly, the screw heads are flawless and some were loctited into the vertical supports for the upper deck, so I'm absolutely convinced the composite chassis is original. 

 

Also... Everything else is as per the original spec, so I can't see that the chassis was upgraded to composite without changing a single component... surely that's the opportune time for an upgrade!

 

Thanks for the interest, I just hope that I can restore it to it's original glory! One thing is for sure,  I'm not planning to put it on a shelf to just look at! 😉

[tomr]

Nice rebuild 👍 it’s looking great . I used to race one of these back in the day ,I never Broke anything apart from the front knuckles.It was fantastic,I sold it and bought a Lazer ZX kit but never really got on with it .

[Drapes86]

On 23/11/2020 at 20:42, Dan_Q said:

Great car, hope you enjoy the build and drive once complete

I ran one of these back in the early 90's, got it second hand from LOOT, it was old and undesirable at the time and I couldn't get parts for it even then! Mine is also a composite chassis and deck, I believe mine is original but cant be 100%- maybe we have later ones as someone has suggested.

I ran mine on 1700SCE nicads, and the 240 ST motor gave it a good turn of speed! I say try a modern ESC with the stock motor ad decide from there I did actually burn out the MSC on mine eventually, which resigned it to retirement and i went back to using my mardave mini!

All the best, I'll keep an eye on this one 😍

Thanks Dan! I'm rebuilding it to the exact spec I found it to establish what works and what doesn't and then go from there. During disassembly, the screw heads are flawless and some were loctited into the vertical supports for the upper deck, so I'm absolutely convinced the composite chassis is original. 

 

Also... Everything else is as per the original spec, so I can't see that the chassis was upgraded to composite without changing a single component... surely that's the opportune time for an upgrade!

 

Thanks for the interest, I just hope that I can restore it to it's original glory! One thing is for sure,  I'm not planning to put it on a shelf to just look at! 😉

[Drapes86]

I've found the first missing parts from the car... 😭

 

There should be two collars that support the wing stay which are secured by the 4 x bolts. Any ideas where to source these?

 

I've done a Google search and there are lots of wing stays available but primarily for the later Kyosho models, but not the Optima.

 

Fortunately they won't stop me finishing the rest of the car 👍

 

Sorry for the lack of progress over the past couple of days, I'm waiting for my ModelSport delivery to arrive!

[bertberr]

Do you mean the two wing stay joints/supports that go horizontally between the wing stays?  If so they are part of the wing stay set - OT99.  I believe there are repro/3D Printed options out there, but not cheap. Alternatively just mod a couple of generic alloy versions to fit.

[Drapes86]

8 hours ago, bertberr said:

Do you mean the two wing stay joints/supports that go horizontally between the wing stays?  If so they are part of the wing stay set - OT99.  I believe there are repro/3D Printed options out there, but not cheap. Alternatively just mod a couple of generic alloy versions to fit.

Yes, you've got it. How would you go about modding a generic version?

 

My initial thought was to find a plastic rod of some sort,  which I could cut to length and drill the ends, with the hope that the screws will bite into the material and hold secure...

[bertberr]

Yes, just use some black plastic tube/spacer/stand-off, the originals are square section, but nobody would ever notice unless they were a massive bore or judging an originality contest.  They are 18mm in length, and originally 4 x M2.6x12 self tappers were used all the way through wing stay, angle adjuster and into stay joint.  Personally, I'd just grab a couple of hex section spacers / stand offs from ebay, they do them in 18mm so you wouldn't even need to trim them up, only a couple of quid for two, and then just use the more readily available M3 tappers (in black!).  Or you could go round section in either black plastic or some non-anodized alloy, your choice really.

[Drapes86]

3 hours ago, bertberr said:

Yes, just use some black plastic tube/spacer/stand-off, the originals are square section, but nobody would ever notice unless they were a massive bore or judging an originality contest.  They are 18mm in length, and originally 4 x M2.6x12 self tappers were used all the way through wing stay, angle adjuster and into stay joint.  Personally, I'd just grab a couple of hex section spacers / stand offs from ebay, they do them in 18mm so you wouldn't even need to trim them up, only a couple of quid for two, and then just use the more readily available M3 tappers (in black!).  Or you could go round section in either black plastic or some non-anodized alloy, your choice really.

Great suggestion and thanks for the detail, I'll get onto that today! Thanks 👌

[Drapes86]

New battery and charger arrived today!

 

I've had to create a female-female tamiya connector because the Optima has a male connector for the battery connector - presumably to push the sale of Kyosh batteries back in the day?

 

DIY plier crimping done and I've tested the motor with the mechanical speed control... They seem okay to me! 😉

[Drapes86]

She's alive!!! 😍

[Ag100]

I had that Techniplus with mine, good to see it all working👍🔥

[Drapes86]

3 hours ago, Ag100 said:

I had that Techniplus with mine, good to see it all working👍🔥

Now I'm really excited to get it all back installed! Until now I've been building it with doubt in my mind that it will actually work... 

[Drapes86]

So all was going well testing the kit off the car, so on it all went. However, the mech speed controller fried as soon as I turned the power on 😭 Any ideas what I could have done wrong??

 

Maybe it is time for that new ESC after all! 😂

 

The steering servo is working nicely though and the tracking is good 👌

 

 

[Drapes86]

13 minutes ago, Drapes86 said:

So all was going well testing the kit off the car, so on it all went. However, the mech speed controller fried as soon as I turned the power on 😭 Any ideas what I could have done wrong??

 

Maybe it is time for that new ESC after all! 😂

 

The steering servo is working nicely though and the tracking is good 👌