Kyohso Javelin/Optima resurrection
 

O.k. So I've just got back into R.C. after a break (kids+life got in the way...) and brought 3 new Schumachers K1 K2F and K2R. If you are in this part of the forum you have probably already stopped reading and run screaming, but for those still with me let me continue.
Apparently the New Zealand RC community (well the electric offroad side...) has gone Vintage nuts. We even had a Vintage National champs a few weeks ago... Anyway, I've been friends with Fathead on the forums here for a while now and he seems to have some sort of horrid VRC infection and it's catching.
I am a part time hoarder, and a while ago (talking 8-10 years maybe) inherited some boxes of old RC junk from a friend who knew I raced and thought I would be interested. Never really looked that much into what was in those boxes. I sort of knew there was a bunch of old Kyosho stuff in there so the other day I decided to investigate.
So. after an hour or so of sorting I came up with pretty much 2 or 3 cars worth of old Optima series in parts and this:
http://i833.photobucket.com/albums/z...506008b355.jpg

Righto then.

Now I have Vintage RC infection... I forgot how much I loved the old Optima, and Javelin cars, they just look so freakin cool and is how offroad racers should look. Not this BS cab forward body rubbish that has taken over.

So I guess I'll start on the journey of turning this into a viable racer, with as many original components as possible, but updating some bits for reliability and performance where necessary.

Feel free to tune in, tune out, tune your favorite mandolin and sing along, whatever you like!

Maskellator.

You're dooooooomed!

It's all down hill from here maskie lol

The only cure is to immediately start giving away all your vintage RC stuff to people that post in this thread, and never look back. :D

But I agree, these older designs are much cooler than Cab Forward stuff.


@Retro: did you get my PM?

Yes I do believe I am already in trouble.

I've done a bit of a stocktake on what's there.
plenty of arms, gearbox cases, and alloy bits in varying degrees of straightness.
http://i833.photobucket.com/albums/z...504_193511.jpg
Driveline is my main area of concern. There are a couple of drive chains, and plenty of diff housings, but i'm not sure on the longevity of the units and how they will stand up to even a 17.5 spec motor...
http://i833.photobucket.com/albums/z...0148d21072.jpg
There appears to be what I thought would be a viable belt drive assembly, but the belt has a twist that might not come out so the tracking might be a problem. I might be able to find a belt, but then as I looked further the drive gear is different to the diff halves for the chain drive, and the teeth look a bit average...
Also I have 3 of the intermediate alloy 'pinions' that run on the layshaft, and they are all a little on the chewed up side.
Now I realize that it is a near 30 year old car of unknown usage, but something tells me that the drivetrain is going to need a bit of work.:mad:

I quite possibly will be able to cnc you up a diff pulley to fit so you can use modern belts which are available almost any tooth count needed.

Yeah, I'm looking at the tiny 2 spider gear diffs and the sketchy intermediate gears and thinking a complete new driveline setup might be in order.
It would probably be easy enough to modernize the drivetrain, using ball diffs, belt drive and figure out a new spur/layshaft/idler setup that is sustainable.

Damn those belt drive conversions were worth more than gold when they came out :D i bought 1 for the salute I had and it cost almost as much as the whole kit did to start with:(

Looks like you've got a nice pot of gold there maskie could probably sell some of those parts out to pay for your new addiction lol

Optima fan pm sent:thumbsup:

Looks awesome!!!! Can't wait to see this progress....

Some people claim the belt conversion kit is not needed, as the belt only has true tension on the bottom "return lane" and not on the upper "lane". Though I wonder if that also applies to braking, and reverse. I would prefer the extra idler roller to be there, but it doesn't appear to be a very sturdy setup, compared to cars that were developed as belt drive from the beginning, like the Mid.

Lots of Optima love here :thumbsup:

Yes I have a belt setup without a idler roller on my Optima mild runner. No problems so far.

I too spent some time trying to find an idler gear to go for a belt conversion but after not finding one I simply went with the 2 ball diffs (parts 107 and 108 I think?) and a standard belt.
My Optima has been fine without the "official" conversion or even the post fitted idler conversion.
If you find my thread on here about my optima rebuild there are some really helpful posts from other optima drivers to help with either doing the conversion or sourcing the parts.
I ran initially with a 17.5T motor but have used a 13.5t for the past 6 months with no ill effects

Just for info: the special belt W0105-1 is not needed for the belt conversion! Belt OT-89 is a 100% alternative!

Hey all, thanks for the input. I will do a bit of digging around and see whether the drivetrain is saveable or if I look at changing it out for more modern components where I can.
The big headache for me at the moment is the diff drive pinion setup. All of the ones I have are pretty ugly and I wouldn't be too happy to run them long term. They also seem to be horrifically expensive to replace... The diff gear for the belt drive is also quite worn, so I'll have to see whether replacements for that are too pricey as well.
I also only have 1 spur/idler drive gear, and while it is in good condition, if I'm going through the effort of getting this thing raceable, I want to know it will last and if it breaks/wears out I can find replacement parts that don't require a mortgage extension...

Has anyone run the stock chain drive setup for any length of time, or is it just more of a headache that it's worth? Realistically I will only really look at running a 17.5 brushless (yeah I know, modern stuff...) in it, so mild by todays standards, but probably fairly potent compared to what was around 30 years ago...

I ran mine briefly with the chain and also discovered that the Kyosho Rocky 4wd chain is the same type, but slightly shorter so if you need a new chain search for those as they are more readily available. I bought 3 and made 2 good chains with enough spare links from the 3rd to do another 2-3 if needed.

Thanks Ashlandchris, yeah I might try running it with the chain and see what happens. I need to find a new belt for it anyway so I will give it a go as it was originally made...

In other news, I have decided that this one will be a runner to race in vintage meetings, I will use the silver chassis parts and polish them up. the gold ones can be for a shelfer if I ever get that far. They are not in brilliant condition but we'll see. I have enough parts to make 2 cars pretty much.

So I took some grubby bits:
http://i833.photobucket.com/albums/z...510_195433.jpg

And turned them into not so grubby, with a bit of elbow grease and Brasso...
http://i833.photobucket.com/albums/z...510_202056.jpg

I'm gonna get Fathead to make the shock towers and radio plate from carbon, so it should look sweet against the polished alloy.

I'm kinda stuck now until I either find some 3mm threaded rod or some long ass screws to go through the rear trans cases into the motor plate. I seem to only have 1 of them and that one is buggered...

Looking good mate:thumbsup: how long do you need screw wise I've got some long m3 screws from my X-ray days that may work.
I see john sold his ultima did you get it by any chance

Pretty sure I saw some M3 rod laying around the other day

Sweet, the screws need to be at least 44MM long, but don't need full length thread.

I'll check tonight you might be in luck

O.K. not much progress this week. I have tracked down a supplier for m3 threaded rod, but I have to but 5 1M long length rods to get it.... Oh well, other projects are planned...

Anyway I have found a set of shocks that I can use that are almost period, but at least are not big bore things that are all de rigeur these days.

http://i833.photobucket.com/albums/z...517_155330.jpg

The only problem is all the blue anodising. Ew.

So, question for you lovely readers. Best way to remove it? oven cleaner? want something that is the safest for the aluminium as I'm dealing with unknown quality as well as threads etc I don't want eaten!

Re anodise them there's a place on the Concourse in Henderson you could try

Sorry Maskie forgot to look for those screws I'll look tomorrow:blush::blush::blush:

I already sent him a pic of my rod.......:lol:

Trust you to send him picks of your rod when he's after a screw on the Internet :lol:

Off topic but Fathead was the master of that some 10-15 years ago lol! :D


So did you find some rod Fathead?

You guys need to get a room :woot::woot:

A couple of easy choices for those. M3 x 45mm screws are available from several r/c companies.

Axial part number AXA0094 and AX31202
Team Associated part number 89279
FS Racing part number 83031, these are phillips head like the originals, all the others are cap head.