Lazer2000/Alpha Toyota Celica Rally - Layshaft done!!!

[EvolutionRevolution]

Okay, let's first see if I get this right:

Lazer 2000 = Lazer Alpha = Lazer Rally = plastic tubbed chassis with plastic shock towers, plastic shocks, wide bumper, and all plastic parts made from a softer plastic.

Lazer Sport = cheaper Lazer ZX with Kelron chassis.

What parts are interchangeable between these and the Lazer ZX, besides the shock towers, shocks, and other suspension parts?

[davsrc]

the only thing interchangable off the lazer 2000 i think are the belts, diffs, outdrives, dog bones,its really junky, lazer 2000 not good Davsrc....

[Mr. ED]

Also the axle carriers in the rear, and c-carrier plus knuckles upfront are transferable from the alpha I believe.

[EvolutionRevolution]

I get the impression Kyosho sold several different chassis under the same names in different countries. Or there's just some confusion on these chassis.

Lazer Sport: http://www.tamiyaclub.com/showroom_model.asp?cid=97543&id=5484 http://www.tamiyaclub.com/showroom_model.asp?cid=94061&id=5927

Lazer 2000/Alpha/Rally: http://www.tamiyaclub.com/showroom_model.asp?cid=100102&id=32213 http://www.tamiyaclub.com/showroom_model.asp?cid=109830&id=36125
The rally version uses 230 mm wide bodies. I'll be getting one of them, without body (which I already have). Here's a similar one: http://www.tamiyaclub.com/showroom_model.asp?cid=40949&id=154

There's also a Pureten Alpha EP, which is a horribly cheap rear motored 200 mm wide chassis, AFAIK.

What I want to know is whether the Lazer 2000 tub can be swapped for a Lazer ZX chassis or if I need additional parts to do so. Of course I can also wait until I actually have my chassis in hand...

[Mr. ED]

The gearbox cases are different, not only in mateial but also in dimensions and mount points, even the moterplate is different shaped. The topshaft is hexagonal and works only with the original crappy spur. No slipper.

[EvolutionRevolution]

Having finally received one, it seems this chassis indeed had some variations. Mine has the standard alloy Lazer ZX 2-piece motor plate. Bathtub chassis parts and gearboxes look like they are hard ABS. Bumper, upper links, shock towers are a bendy plastic that feels quite tough (unfortunately it's not suited at all for the shock towers, as I can bend those muchly by hand ). Front uprights, c-hubs, rear uprights, and body mounts look like they are standard Kyosho black nylon. The other parts including the a-arms are not hard plastic but some other kind of bendy plastic, I guess some kind of nylon. I'll need to take the car apart and clean everything up to get a really good look.

The only hinge pin mount chassis-side that is part of a gearbox is the rear mount on the front gearbox. The other three are separate pieces. No adjustable links, alloy wheel hexes, metal wheel nuts (they're nylon!), alloy/carbon steering plate or good quality shocks. The outer hinge pins are long tapping screws - one of which of course has been tightened too much , splitting the hole in the a-arm...
Front belt tension is ridiculously absent as are ball bearings or a belt tensioner. The lower belt guide has a thin lexan cover held on by cellotape, while the rear gear cover presented a nice surprise, as the previous owner forgot to remove the protective film (so it's like brand new). Quick-release body mounts are present, and it looks like the steering set up actually uses Kyosho's standard alloy posts on which the steering parts rotate, so the steering can be upgraded to ball-bearing steering.

Soooo...project:
1) Take apart and clean up car
2) Reassemble and upgrade. Confirmed upgrades:
- Equalizer shocks
- Lazer ZX a-arms and uprights
- universals
- anything that fixes the issues of the chassis

[EvolutionRevolution]

One more difference under the hood:

No press-on drive hexes, instead they use pins, which is interesting as the body mounts clearly show that this is one of the first releases of this chassis, back from the 1990s, when Kyosho still used the press-on hexes on their other cars...

Also, for those hoping to swap the layshaft with the one from the Kyosho Spider EP/TF-2/3, it is not possible. The front and rear belts are swapped left-right between the cars, despite the layshafts being almost the same length. So it isn't possible to use the front one-way pulley and still have front drive (oneway bearing is upside down) or rear drive (rear pulley won't fit properly on layshaft). Using the layshaft without the oneway pulley is possible, but then the spur gear holder won't fit properly.

[sgirouard]

I had one of these and was looking at different ways to make it more "race-bred". For starters, you really need to stiffen the chassis. I looked at running a threaded rod with ball ends from the front to back which would double as a belt tensioner.

[Mr. ED]

The axles with the crosspin were the best part on this car as far as I'm concerned. I've used these (and others like them) to switch to modern hexes for my ultimas and other projects

[Coelacanth]

The axles with the crosspin were the best part on this car as far as I'm concerned. I've used these (and others like them) to switch to modern hexes for my ultimas and other projects

I would agree. When I restored my original Zebra Optima, I found that the wheels would spin loose all too often with a really powerful 14T brushed motor and those press-fit hex hubs. I ended up buying brand-new 4mm nylon lock-nuts to help resolve that issue. With any Optima I built or will build afterwards, I switch to axles with cross-pins--at least for the rears.

[EvolutionRevolution]

I had one of these and was looking at different ways to make it more "race-bred". For starters, you really need to stiffen the chassis. I looked at running a threaded rod with ball ends from the front to back which would double as a belt tensioner.

I suspect that most chassis breakages are actually caused by bad chassis design. The chassis is badly cracked right where the rear screws for the front gearbox and the screws for the front rear hinge pin holder go through the chassis, as far as I can see because A) the holes are too close to the edge, and B) due to the shape of the chassis those parts will be leveraged against the tub in an impact. Who at Kyosho thought it was a good idea to put those screw holesright on the spots that gets the biggest loads in impacts without adding additional plastic for reinforcement?
Edit: Some current Ebay auctions show that later versions of this chassis have reinforcements at exactly those two locations, however I am happy that mine doesn't have them because the reinforcements would mean a stiffener for the whole chassis would not fit.

Another thing that strikes me as strange is the belt cover for the lower belt guide. Sure, the belt is covered, but what is the use of a cover when dirt can enter the lower belt guide from the underside, where there are two huge holes...?

So what I am thinking of doing is to create a lower chassis plate that slots into the bottom of the chassis, covering the holes in the bottom (which should prevent dirt from ending up in tight spots too) and adding new holes for the screws to go through, so the original holes bear less of a load. I'll use glassfiber for toughness.

Can someone tell me where pargu2000's Laser ZX belt tensioner (http://www.ebay.com/itm/vintage-kyosho-LAZER-ZXR-LAZER-ZX-ALLOY-belt-tentioner-/140622445755?pt=Radio_Control_Vehicles&hash=item20bdc03cbb) is supposed to fit on the ZX chassis?

[isobarik]

it sits just in front of the batteries.

Can snap an pick when i recive mine.

mvh Isobarik

[EvolutionRevolution]

Some pictures of the chassis tub to start with:

Chassis top and bottom:

Pretty scratched up, and the previous owner butchered some of the screw holes - including the ones for the steering servo, so that will require some fixing.

The cracks:

Basically, wherever it is possible for a gearbox or bumper to be leveraged against the chassis.

[EvolutionRevolution]

Confirmed hop-ups:

Equalizer shocks and universals.

And some new body mounts, because this chassis was originally used with a Pajero body (which I don't have) and I will be using a Toyota Celica instead:

I got started with the rear gear box, into which I installed a Team Atlas ball diff, with the diff pulley replaced by a Kyosho Pure Ten diff pulley because the original Atlas version used 2.4 mm balls which I didn't have. Furthermore, I plopped two 3x6 mm bearings into the hole meant for the brass roller, to prevent the belt from rubbing the inner gearbox wall.

Tolerances seem to be a bit off on this gearbox, and I had to take it apart again after initial assembly because the diff appeared to be too wide for the gearbox. Cleaning the bearing holes meticously and putting it together a second time fixed this issue. Also attached the motor plate.

Other side, showing the room I've got left between the motor plate and the first layshaft bearing. My objective is to add a custom slipper around the original hex layshaft.

And the front belt is installed, again with ball bearings replacing the brass roller:

I then bolted the completed rear gear box to the chassis through the forward screw holes of the motor plate. Two Kose stand-offs were attached to the holes for the wimpy plastic front stiffener (which I won't be using), instead the car will get a custom two-piece top deck. I also installed ball-bearing supported bellcranks off a TF-2 instead of the stock bellcranks, with the TF-2 steering posts installed upside down instead of the alloy tubing of the original car:

I will need to shim the bellcranks a bit to make the entire assembly free of play. The pivot ball for the servo link will possibly need to be installed the other way around if the belt hits it once the front gearbox is installed, but this will require modifying the chassis because the servo link hits the lower belt guide in stock form - another chassis design issue.

I also determined that it is quite likely that the only reason for the horrible front belt tension is that the rear half of the chassis is too flexible to properly support the weight of the car

Another view of the chassis, with TF-2 steering plate (on ball bearings) installed instead of the stock flexy plastic unit:

And assembled body posts:

[EvolutionRevolution]

Bonus: Lazer Alpha/2000 front gearbox versus Optima Mid front gearbox:

Quite similar, and indeed you can use the Optima Mid's shock towers on the Lazer.

Now for a Lazer-related question: Are there any differences between the rear gearbox/motor plate of the Lazer ZX and ZX-R? I'd like to use Fibre-Lyte's ZX-R's Motor stabilizer plate (left gear box plate) and want to know whether it fits.