lazer zxr for winter racer

[rob m]

Hi all. First of all i would like to thank you for the advice and help you gave me in a previous thread for my zx , but this car has now become spares for a lazer zxr . I have stripped cleaned and rebuilt the zxr to the manual. I am planning to use the car over winter at two venues but want to keep the car as original as possible or with period upgrades.
The items i have changed are the shock towers for carbon fibre items with the front having the much needed bridge for strength, associated plastic servo mounts. Also the pistons in the option house shocks for modern lazer mk5 items (w5181-03 piston set). I am using lipo saddles 5600mah 95c and brushless 6.5t hpi motor 100t spur with 23t pinion.

Before i put my pride and joy up against the new cars i thought i would ask for the knowledge from the expert vintage lazer racers.....

is the manual a good starting point for a set up of the car?
What shock oil/pistons and lb springs to use front and rear?
Will the slipper be up to the job with a 6.5t brushless?
Any weak areas for the car to watch for?

The track surfaces i will be racing on are a hard rubber floor(indoor running track) , also a mixture of carpet/polished floor.

[Mark H]

Keeps us up to date how you get on just getting my lazer zx ready for the winter after its last race with me in 91, I changed my spurs for the Teflon back in the day so staying with them.

[Welshy40]

Originally Posted by rob m

Hi all. First of all i would like to thank you for the advice and help you gave me in a previous thread for my zx , but this car has now become spares for a lazer zxr . I have stripped cleaned and rebuilt the zxr to the manual. I am planning to use the car over winter at two venues but want to keep the car as original as possible or with period upgrades.
The items i have changed are the shock towers for carbon fibre items with the front having the much needed bridge for strength, associated plastic servo mounts. Also the pistons in the option house shocks for modern lazer mk5 items (w5181-03 piston set). I am using lipo saddles 5600mah 95c and brushless 6.5t hpi motor 100t spur with 23t pinion.

Before i put my pride and joy up against the new cars i thought i would ask for the knowledge from the expert vintage lazer racers.....

is the manual a good starting point for a set up of the car?
What shock oil/pistons and lb springs to use front and rear?
Will the slipper be up to the job with a 6.5t brushless?
Any weak areas for the car to watch for?

The track surfaces i will be racing on are a hard rubber floor(indoor running track) , also a mixture of carpet/polished floor.

I think your going to snap the belt. Also you should be posting this on the main Lazer thread. Im designing a belt tensioner block to be attached to the gearbox but youll need to cut a section away to do it. Also slipper may not be up to the job either but with a tensioner fitted you can tighten the slipper. Tyres yellow mini pin work fine, gear ratio well id opt to start with a 23 and go up or down considering. Id go for less accelaration more top end to save the belt but would rather you used an 8.5 with the standard gearbox

Set up, well i used traxxas shocks but if you use kyosho shock seals and use three holes front 2 rear you could try 50 front 30 rear with schumacher grey front and schumacher white rear. May also try size 2 all round 35 frt 30 rear.

[rob m]

Had time to give my zxr a test at my local track yesterday. I Was very impressed with it but it did seem soft on the front end lifting inside front wheel in the corners. I will try thicker oil in front . I was happy testing and tweeking, camber etc.......then it happened! Rear belt broke!.....well thats what a thought, got home stripped gear box to find all the teeth had come off!

[Welshy40]

Originally Posted by rob m

Had time to give my zxr a test at my local track yesterday. I Was very impressed with it but it did seem soft on the front end lifting inside front wheel in the corners. I will try thicker oil in front . I was happy testing and tweeking, camber etc.......then it happened! Rear belt broke!.....well thats what a thought, got home stripped gear box to find all the teeth had come off!

Get a new LA11 and a new rear belt. Then before you rebuild it hold fire for a short time as I am almost done with my redesign as I have had a few carbon fibre brackets sent across to me and will try building this weekend and if happy will order some bits and pieces and sell as a small added kit with manual on how to fit the rear belt tensioner.

Also are you sure its not the rear you need to thicken. What surface are you running on and what oil and springs and pistons are you using? Also what tyres and inserts and are you using a roll bar?

[rob m]

Originally Posted by Welshy40

.Also are you sure its not the rear you need to thicken. What surface are you running on and what oil and springs and pistons are you using? Also what tyres and inserts and are you using a roll bar?

Your belt tensioner sounds a good idea as my guess is the belt on the none drive side slaps about at speed and causes the belt to jump resulting in a broken or stripped belt.

i understand what you mean with the rear end, but on the track the rear seemed rigid with not much roll and in the corners it skipped/bounced a little, in the slow corners the car wanted to hook.
ive been testing my car on high grip astro but want to mainly use it indoors at two venues with a hard rubber floor ( indoor running track ) and also carpet/polished gym floor.

ive been testing the car on astro using scumacher yellow mini spikes with medium inserts outside row cut off front and rear. Also i have medium and soft foams and soft rubber slicks which i was thinking of trying indoor.

my set up so far is as follows....

FRONT
Option house shocks with zx5 fs piston 2-c, 35wt ae oil and original gold springs (maybe silver but i think gold as they look faded)
lower shock position is outside hole
upper shock position is 70mm apart (lots of holes to choose)
camber link on tower is top row 3rd hole in from outside.
been thinking about trying ae blue springs??

REAR
option house shocks with zx5 fs piston 2-b, 30wt ae oil and kit black springs.
lower shock position is middle hole
upper shock position is 75mm apart (again lots of holes to choose)
camber link on tower is top row outside hole
camber link on hub is middle hole top row.
rear brace is number 1 and position is as manual
been thinking about trying ae silver springs??

i do have the original black pistons with two holes and the red pistons with one square notch on the edge if they will be better to use?
I would like a roll bar but don't know were i could find one or if any can be made to fit from a current rc car...was thinking b44 or another one i seen which has little clips for mounting it.

[oli4ke]

Originally Posted by rob m

I would like a roll bar but don't know were i could find one or if any can be made to fit from a current rc car...was thinking b44 or another one i seen which has little clips for mounting it.

Pricey but a complete set is available on ebay. See link below.
http://www.benl.ebay.be/itm/Kyosho-L...5#ht_330wt_932

Brgds,

[Welshy40]

Originally Posted by oli4ke

Pricey but a complete set is available on ebay. See link below.
http://www.benl.ebay.be/itm/Kyosho-L...5#ht_330wt_932

Brgds,

Too expensive. do a search on the part number on google and ebay and youll probably find it for maximum 30 euros.

[Welshy40]

Your belt tensioner sounds a good idea as my guess is the belt on the none drive side slaps about at speed and causes the belt to jump resulting in a broken or stripped belt.

Belt doesnt jump, it fluctuates under power as there is nothing keeping the belt from moving in the gearbox other than the pulleys and those crap brass bushings which actually dont do anything. These were taken out by myself and also Jon Tucker (he qualified for the worlds with a ZXR) as they damaged the belts. The belt needs a bit of tension to stop the fluctuation as that can stretch the belt and bang it snaps whereas with a tensioner it keeps it all in place and less fluctuating means it stays pretty much perfect and lengthens the lifetime of the belt by several years, quite possibly youll get five years out of a belt if maintained correctly. Im lasting a bit longer than that on mine.

i understand what you mean with the rear end, but on the track the rear seemed rigid with not much roll and in the corners it skipped/bounced a little, in the slow corners the car wanted to hook.
ive been testing my car on high grip astro but want to mainly use it indoors at two venues with a hard rubber floor ( indoor running track ) and also carpet/polished gym floor.

I believe the back is too hard, first would go down a spring. Also would advise using a longer tie rod adjustment on the rear but not the longest setting and that way gives you more droop and also does make a difference on this car. A roll bar on high grip is needed as I only ever use it indoors. I would also set the car a bit lower so Ujs should not be level and be slightly under when on the track on the rear and also use a larger wing. Springs personally always go softer on the rear so me I would opt for trying associated silver but may go down to green on the rear with 30 weight and on piston size smaller than the front.

Front I use the top outer tie rod hole and use the blue steering with a zx steering plate as then you have zero bump steer. I know Jamie Booth preferred the ZXR angled steering plate but I couldn’t get on with it so down to you. Springs on the front start with associated blue but may go down to silver, personally I found Losi red works well on mine better than the blue or silver but my shocks are traxxas. Piston needs to be one softer than the rear which does sound weird but try it and see.

Front outer hole used on the front castor block and longer Ujs makes a huge difference so hope your using that.

ive been testing the car on astro using scumacher yellow mini spikes with medium inserts outside row cut off front and rear. Also i have medium and soft foams and soft rubber slicks which i was thinking of trying indoor.

Answer Blue inserts are what I use and on carpet and shiny floors I use mini pins but on astro yes mini spikes are fine. TBH inserts are really down to preference so go with what you feel suits you.

my set up so far is as follows....

FRONT
Option house shocks with zx5 fs piston 2-c, 35wt ae oil and original gold springs (maybe silver but i think gold as they look faded)
lower shock position is outside hole
upper shock position is 70mm apart (lots of holes to choose)
camber link on tower is top row 3rd hole in from outside.
been thinking about trying ae blue springs??

REAR
option house shocks with zx5 fs piston 2-b, 30wt ae oil and kit black springs.
lower shock position is middle hole Try outer as well
upper shock position is 75mm apart (again lots of holes to choose)
camber link on tower is top row outside hole
camber link on hub is middle hole top row.
rear brace is number 1 and position is as manual
been thinking about trying ae silver springs??

i do have the original black pistons with two holes and the red pistons with one square notch on the edge if they will be better to use?
I would like a roll bar but don't know were i could find one or if any can be made to fit from a current rc car...was thinking b44 or another one i seen which has little clips for mounting it No harm in trying, the softest one is the best to go with for this car

I will try to post some pics of my ZX on your thread this weekend so you can see my tie rod placement. Yes my car is set for carpet but youll get an idea from it. Also are you using any weight on the chassis as don’t forget the car was designed to carry roughly 220 grams more weight, so as your now using Lipos and this does change the characteristic of the cars handling. Mine ive addded 85 grams on either side but have the option of adding brass plates doen the middle between the lipos. Im testing my new chassis with these weights in two weeks time and will uipdate on it how it went with all the weight added and also without.

Where are you based again as I have forgotten.

[rob m]

Thankyou for the advice welshy40, i will try what you have advised me on and see how it goes.

uj's
i am using the original front uj's and the original dog bones in rear....what would you recommend to use?

weight
Regarding the weight of the car with using lipo's, when i made my lipo holders at work i designed them so they would bring the lipo's up to the same weight as some old ni-cads i had in my loft (380g). I forgot to mention that i am using zx gear diffs front and rear, would i be better off putting the zxr ball diffs back in?

i do have a lazer zx aswell .....would the zx be more competitive indoors then the zxr?

i'm based in north manchester

[rob m]

Originally Posted by oli4ke

Pricey but a complete set is available on ebay. See link below.
http://www.benl.ebay.be/itm/Kyosho-L...5#ht_330wt_932

Brgds,

thanks for the link but to expensive at £40

[Welshy40]

Originally Posted by rob m

Thankyou for the advice welshy40, i will try what you have advised me on and see how it goes.

uj's
i am using the original front uj's and the original dog bones in rear....what would you recommend to use?

weight
Regarding the weight of the car with using lipo's, when i made my lipo holders at work i designed them so they would bring the lipo's up to the same weight as some old ni-cads i had in my loft (380g). I forgot to mention that i am using zx gear diffs front and rear, would i be better off putting the zxr ball diffs back in?

i do have a lazer zx aswell .....would the zx be more competitive indoors then the zxr?

i'm based in north manchester

Ujs well i did do a post aling with Iso in the Lazer thread so you should find something within the last 20 pages.

Zxr would be a better option for you. Gear diffs are fine but would recommend packing out with grease and not oil.

Pics of your lipo holder please.

Ive just completed my build of my tensioner for the rear gearbox and needs a slight mod and then i can order a few bits and pieces and will sell as a tensioner kit. You need about twenty minutes but better doing it at a relaxed pace so you dont mess it up so maybe an hour to do it.

Pics will follow on the lazer thread sometime this weekend

[Welshy40]

Forgot to mention but as your in Manchester doing the Maritime race event in kent is a bit far for you to come to learn about the car.

[Welshy40]

Hope these pictures help. If not just ask. FYI Lipo tray not yet fitted as the design was flawed.

[rob m]

pics of my lipo holder as asked, simple really couple of end plates and a plate down the middle attached with double sided tape to stop lipo's moving around,i am going to make the plate in middle in different weights if i feel the need add or remove weight

[rob m]

impressed with your car welshy40, ive noticed the odd modification on it from the standard zx.....is that your re-release tub chassis i see? Also is the front gearbox casing an alloy item you have made?. I have been thinking of making my own version at work when the time comes.but for now i still have four bnip.

Here are some more pics of my car, ive followed your advice but yet to test the car as i need either a slower motor or a belt tensioner, as you can see it is pretty much original apart from the shock towers.

The Front caster blocks in last picture, can anybody tell me what make they are please?

[kek23k]

Originally Posted by rob m

The Front caster blocks in last picture, can anybody tell me what make they are please?

They were made by Teamline, kinda like a factory team optional upgrade. They are much more robust than the original items and came in two different castor options. They were also ballraced round the kingpin and the ones in the photo appear to be missing the flanged bearings.

[Welshy40]

Originally Posted by rob m

pics of my lipo holder as asked, simple really couple of end plates and a plate down the middle attached with double sided tape to stop lipo's moving around,i am going to make the plate in middle in different weights if i feel the need add or remove weight

Looks nice and only things id do is turn the very rear pivot block upside down as it gives more kick up and makes the rear slightly better, also make the angle on the front shocks on the tower the same as the rear. Your lipo design looks very similar to my original design in cf ive been using for the last couple of years, since the trf511 came out. Ive designed my middle block with a milled bottom so left and right have flat spots higher up so i can fit brass weights in the cell holes and a brass plate ontop plus brass weights on the centre block as well as having the option on half weights as well. This item bolts to my chassis. Updated design on my tub.

Motor wise when a tensioner is fitted you can easily use a 6.5 motor, me im using a 4.5 for testing and so far havent stripped a belt.

[Welshy40]

Originally Posted by rob m

impressed with your car welshy40, ive noticed the odd modification on it from the standard zx.....is that your re-release tub chassis i see? Also is the front gearbox casing an alloy item you have made?. I have been thinking of making my own version at work when the time comes.but for now i still have four bnip.

Here are some more pics of my car, ive followed your advice but yet to test the car as i need either a slower motor or a belt tensioner, as you can see it is pretty much original apart from the shock towers.

The Front caster blocks in last picture, can anybody tell me what make they are please?

Odd mod is an understatement. About 20 percent is original, new designs are total new rear gearbox design including new layshaft and vts slipper clutch, new rebuildable ujs, new rear hub from the zxs, pure ten steering, new front & rear towers, Top deck & new updated tub now available and one off front gearbox. Side walls on that are cf with a top and bottom section that screws onto the cf wall so you can mount the top deck and bolt to the chassis, and a 3mm higher rear top deck mount which ive persuaded a 3d maker to sell as well, but mine is a one off alloy & testing the 3d plastic soon when it arrives. Main bit of the gearbox is thin alloy.

Chassis is a spin off from my very first design with a few tweaks. You can buy but youll need to specify what design you want cut from the tub but would advise sticking to the side walls height being 20mm high and the back end wall edges being rounded off. Every one has their own idea but hey i only designed the original tub so have a valid reason.

Belt tensioner is designed and now am working on a manual and finding the correct parts to sell as a complete package so all you need do is cut the gearbox to my specifications and game on.

[rob m]

Originally Posted by kek23k

They were made by Teamline, kinda like a factory team optional upgrade. They are much more robust than the original items and came in two different castor options. They were also ballraced round the kingpin and the ones in the photo appear to be missing the flanged bearings.

i have the bearings still so will give them a try. Thanks for the info.