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lil rock buggy class specs on page 6

General Tech Talk

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Post by Ingenious-Eng »

Shadow wrote:interesting idea with the power steer pumnp. Only problem i can see is that the low pressure side of the pump may not be able to handle the full pressure as in the high pressure side? i guess experimentation is in order >_<


If you got 4 4wd pumps for the wheels, and a big ass truck power steer pump attached to the motor, you could then also run all your steering etc from hydro aswell.

I wonder how much torque a power steer pump would have before you blow seals in the pump.
For a pump to become a motor you can make what was the output when it was a pump the input to make a motor so the high pressure side is the same, only mods to make it a motor that I can think of is to block off the pressure relief valve & fit some springs behind the vanes to hold then out against the wall (if they don't have any fitted allready)
As for seals blowing! the pumps have pressure relief valves fitted standard so no probs there, the idea to have one pump to one motor is two fold in that if they are they are both the same size then what ever rpm the pump is doing the motor will be doing approx the same, thus the reduction can be done at the wheel keeping any stall type loads away from the hydraulic system the other advantage is it works like you have diff locks because each wheel is being driven seperatly and as long as the gearing is right the wheels with traction would still spin without stalling.
Steering could be enhanced by speeding up the pumps on one side (by using variable pullies) during the turn whilst still giving true 4 wheel drive some thing that diff locks can't do.

the drivetrain possabilites are endless with small scale buggies, easy to borrow bits & pieces from other common machinery & make it work.
:D :D
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Post by "CANADA" »

pen and paper is out now :twisted:
[quote="dazza30875"]whats "FAIL" mean[/quote]

[quote="fool_injected"]

Sometimes your funny Canada :D[/quote]
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Post by slosh »

why not 2 engines or even 4 (maybe pocket bike power)?
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Post by toughnut »

slosh wrote:why not 2 engines or even 4 (maybe pocket bike power)?
MADZUKI and I talked about a completely electric buggy with a motor for each wheel. The whole idea of this is to keep the cost and overall capability of the buggy down so your average booty fab bloke or blokett could build one at home and make them reasonably reliable. I'm not talking about a buggy that could theoretically drive a course that is set out for outlaw class now. I'm talking of setting the course for the light weight class that we come up with. Mind you if we build them light enough your spotter could almost drag you through the course :rofl: The lite weight could be good for safety as well because it wouldn't pull the spotter around as much. ;) Sounds like we might have something going here :armsup:
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Post by Shadow »

Ingenious-Eng wrote:
Shadow wrote:interesting idea with the power steer pumnp. Only problem i can see is that the low pressure side of the pump may not be able to handle the full pressure as in the high pressure side? i guess experimentation is in order >_<


If you got 4 4wd pumps for the wheels, and a big ass truck power steer pump attached to the motor, you could then also run all your steering etc from hydro aswell.

I wonder how much torque a power steer pump would have before you blow seals in the pump.
For a pump to become a motor you can make what was the output when it was a pump the input to make a motor so the high pressure side is the same, only mods to make it a motor that I can think of is to block off the pressure relief valve & fit some springs behind the vanes to hold then out against the wall (if they don't have any fitted allready)
As for seals blowing! the pumps have pressure relief valves fitted standard so no probs there, the idea to have one pump to one motor is two fold in that if they are they are both the same size then what ever rpm the pump is doing the motor will be doing approx the same, thus the reduction can be done at the wheel keeping any stall type loads away from the hydraulic system the other advantage is it works like you have diff locks because each wheel is being driven seperatly and as long as the gearing is right the wheels with traction would still spin without stalling.
Steering could be enhanced by speeding up the pumps on one side (by using variable pullies) during the turn whilst still giving true 4 wheel drive some thing that diff locks can't do.

the drivetrain possabilites are endless with small scale buggies, easy to borrow bits & pieces from other common machinery & make it work.
:D :D
But to drive forward/reverse you need to apply pressure to opposite sides of the pump, so no matter what, the low pressure side will be recieving pressure at either forward or reverse rotation.
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Post by Ingenious-Eng »

toughnut wrote:
slosh wrote:why not 2 engines or even 4 (maybe pocket bike power)?
MADZUKI and I talked about a completely electric buggy with a motor for each wheel. The whole idea of this is to keep the cost and overall capability of the buggy down so your average booty fab bloke or blokett could build one at home and make them reasonably reliable. I'm not talking about a buggy that could theoretically drive a course that is set out for outlaw class now. I'm talking of setting the course for the light weight class that we come up with. Mind you if we build them light enough your spotter could almost drag you through the course :rofl: The lite weight could be good for safety as well because it wouldn't pull the spotter around as much. ;) Sounds like we might have something going here :armsup:
I gave electric a quick thought but quickly dismissed it because of water sealing issues, hydraulic is better because it's under pressure so water cant get in the motors etc, also electric motors are expensive & speed control gear is complicated. hydraulics are simple if you keep it simple, control valves & cylinders from tractors are easy to come by, as are making you own unlike electrics.

Whats this about spotters, NO way :!: one person/driver per car no other help allowed, everyone gets to walk the section first then remember your line then drive it. You roll it your out. No rock stacking, modifing or touching the track in any way. points should be awarded for driving skill like trials bikes. So tyre smoking/buggy bouncing over rocks etc you lose points, if you stop or back up you lose points, harder lines get more points than easy lines etc. each obstical should have a number of possiable lines to take from easy to extreme so even simple buggies can still complete the track, this will allow the kids to compete as well so one car the whole family can compete in.

Are we there yet :armsup:
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Post by Ingenious-Eng »

But to drive forward/reverse you need to apply pressure to opposite sides of the pump, so no matter what, the low pressure side will be recieving pressure at either forward or reverse rotation.[/quote]

True but still don't think it would be much of a problem as they are usally cast iron so there pretty tough anyway, either way I can machine up a vane type motor so cheaply & easily from the power steer pump parts so no probs.

I have a place in mind we could hold the local comp near Brisbane :roll: (after we clean it of course)

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Re: light weight class buggy

Post by bogged »

toughnut wrote:Use a motorcycle engine like an XR650
how do you reverse?
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Post by toughnut »

What have I started :rofl: I've just made even more work for myself :? So what have we actually agreed on.

Light weight

IFS and IFR ( which will help limit things a little )

Motorcycle engine. Must be 4 stroke??? limited to 650cc total capacity ie. if you have two motors you can only have a total of 650cc ;)

I think to keep things more conventional have a solid drive from a central differential front and rear.

no limit on weight

Max wheel base of 2500mm axle to axle and max track of 1500mm :D
Same dimensions as a mini

Wheel diameter of 16 inch rim Tyres free. Must be motorcyle tyre and rim.

steering must be mechanical and must be driven by a steering wheel

Suspension must not be adjustable on the move :twisted:

Suspension must only be adjustable by mechanical means

Axles must be chain driven from a central trasmision or axel :D

Must have convensional brake system and must consist of at least one brake disc ( perhaps on central axle )

Engine must be naturally aspirated and cannot have more than one fuel type to power ;) no nos :D

Heaps more to think of
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Re: light weight class buggy

Post by toughnut »

bogged wrote:
toughnut wrote:Use a motorcycle engine like an XR650
how do you reverse?

mate it to a quad gearbox :twisted:
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Post by Ingenious-Eng »

Them tough rules :cry: toughnut, are we allowed to make it a 6x6 or 8x8 then, or run duels (twin tyres), you know we gunna bend the rules if you don't spell it out for us :rofl:
It almost sounds like one of those chinese buggy thingos they allready selling, you must allready have one an got a head start on us toughy :rofl:
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Post by "CANADA" »

650 is way to big...make it 300-350

Should not be limited to motorcycle rim and tire...ATV tires are 80-120 per tire...these buggies are going to have some cost for them, hopefully under 5k total...

Hydro steering should be alowed...

We would have to build one first to give a basic outline of what they should include in the build..so we dont get 50% of the cars dont pass scruit'
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Post by Beastmavster »

toughnut wrote:
slosh wrote:why not 2 engines or even 4 (maybe pocket bike power)?
MADZUKI and I talked about a completely electric buggy with a motor for each wheel. The whole idea of this is to keep the cost and overall capability of the buggy down so your average booty fab bloke or blokett could build one at home and make them reasonably reliable. I'm not talking about a buggy that could theoretically drive a course that is set out for outlaw class now. I'm talking of setting the course for the light weight class that we come up with. Mind you if we build them light enough your spotter could almost drag you through the course :rofl: The lite weight could be good for safety as well because it wouldn't pull the spotter around as much. ;) Sounds like we might have something going here :armsup:

I talked about this idea quite some time ago, using a stripped down sierra type chassis. The benefits of electric motors are pretty good.

You need no gearboxes, they can run in forward or reverse
Ultra low stall speeds so dont actually need rockhoppers or any of that expensive stuff.
Massive torque relative to power output.
Run on any angle with no dramas
Dig turns and bobcat/forklift style manouevers are easy. Imagine the possibilities.

*trying to do this stuff with petrol engines and throttle linkages is remarkably unsuccessful I can guarantee you.

Issues though - cooling may be a significant problem in hot dusty environments.
Water = bad
Mud = very bad.
Need to buy a few batteries so some are on recharge
Probably need to get a generator to run back at your base.


If you're not after car type 50kw engines then things like electric whipper snipper or mower motors and old washing machine motors are perfect for this sort of building. I betcha you could grab a few motors for free during the next hard rubbish collection, or go down to the tip and pick up a few for $20....

After all, an electric flymo mower motor is about the equivalent of a 150cc petrol 4 stroke motor mower.....





As for tyres, trials tyres are expensive but getting standard trail bike knobbies is pretty cheap for the traction they would provide. Last I checked you could still get cheapo cheng shin tyres for well under $100 - and their muddies are actually good (just never risk your life with their onroad tyres).

The weight issue of the car type rim and tyre really does encourage a lighter option.
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Post by Beastmavster »

Few recommendations:

toughnut wrote:What have I started :rofl: I've just made even more work for myself :? So what have we actually agreed on.

Light weight Set a maximum weight eg 350kg max

IFS and IFR ( which will help limit things a little )

Motorcycle engine. Must be 4 stroke??? limited to 650cc total capacity ie. if you have two motors you can only have a total of 650cc ;)

Allow use of twostrokes but cap them to say 400cc. Good for those who can say score an old DT400 motor out of their back shed.
What about allowing electric engines but a maximum output rating.


Tweak things if they end up getting too biased in favour of one class, or use weight penalties.


I think to keep things more conventional have a solid drive from a central differential front and rear.

Why differential? We want locked diffs dont we? :D
no limit on weight

Max wheel base of 2500mm axle to axle and max track of 1500mm :D
Same dimensions as a mini

Hmmm..... 1.5 metres is VERY wide for a single user - thats the width of a Hilux. You should be able to do 1100mm or 1200mm max.

Wheel diameter of 16 inch rim Tyres free. Must be motorcyle tyre and rim.

Hmmm....Most trailbike rims are 19-21" (even my roadbikes have generally been 18", 19" rims). You should allow them. Tyre sidewalls in motorbikes are tiny by comparison remember, so height is almost all from rim anyway. People will want more than 80cc rear tyre sizes.

If people want to buy ATV tyres, why not let them. In the end if one type is way better than another, start classes when you've got a critical mass built up.

I think you'd be better off capping tyre radius, but since bike tyre sizes tend to max out at about 27" or so anyway, thats pretty easy



steering must be mechanical and must be driven by a steering wheel

Suspension must not be adjustable on the move :twisted:

Suspension must only be adjustable by mechanical means

Axles must be chain driven from a central trasmision or axel :D

Why no shaft drives, belt drives or electric? All of which are potentially safer than chains. I can see environmental reasons to dissallow hydro....

Must have convensional brake system and must consist of at least one two due to safety brake disc ( perhaps on central axle )

Engine must be naturally aspirated and cannot have more than one fuel type to power ;) no nos :D

Heaps more to think of
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Post by "CANADA" »

Artificial Resp should be allowed as well..but possibly take a penalty for it till we can build up another class for it
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Post by toughnut »

So when do we start the build canada :armsup:
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Post by "CANADA" »

ive been trying to get my engine goin most of today :finger:
Ive got my diffs and rear hubs




Whats this we bussiness :finger: :D :D :D
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Post by Nev62 »

Beastmavster wrote:Few recommendations:

toughnut wrote:What have I started :rofl: I've just made even more work for myself :? So what have we actually agreed on.

Light weight Set a maximum weight eg 350kg max
Ok but a minimum driver weight of 120kg, carn't have the string beans have all the fun :D
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Post by "CANADA" »

toughnut wrote:So when do we start the build canada :armsup:

Soon tho...ive got some rhs leftover im going to tac the start of the main chassis...

U got acces to a lathe?
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Post by Beastmavster »

Nev62 wrote:
Beastmavster wrote:Few recommendations:

toughnut wrote:What have I started :rofl: I've just made even more work for myself :? So what have we actually agreed on.

Light weight Set a maximum weight eg 350kg max
Ok but a minimum driver weight of 120kg, carn't have the string beans have all the fun :D
If you're a fat bastard you just have to build the thing lighter to compensate.....


Or you could just lose some weight :P
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Post by DamTriton »

How about IRS with Zook front beam axle? This would give good scope to the rear suspension design, and simplify/standardise the front end, getting over having to have exxy parts for a custom knucle of any sort.

Two purely electrical ideas

1. Independant shaft drive to the each rearwheel from winch motors mounted by drivers side, and another one bolted to the Zook pinion driving the front diff. Power from a generator charging 24 volt batteries. Total of about 12 hp but a shload of torque...

2. Starter motor/flywheel assys bolted to the back of each of the wheel hubs.
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Post by Nev62 »

Beastmavster wrote:
Nev62 wrote:
Beastmavster wrote:Few recommendations:

toughnut wrote:What have I started :rofl: I've just made even more work for myself :? So what have we actually agreed on.

Light weight Set a maximum weight eg 350kg max
Ok but a minimum driver weight of 120kg, carn't have the string beans have all the fun :D
If you're a fat bastard you just have to build the thing lighter to compensate.....


Or you could just lose some weight :P
:rofl: not that heavy, just thinking of the bigger boned folk out there. But in all seriousness if this would be open to everyone then it should not give advantage to the "Jockey Build" wheelers :lol:
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Post by "CANADA" »

wait till we get one prototype built...then we can work on improvements from there and everyone can see exactly what we are talking about
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Post by toughnut »

This is why I said no weight limit. If you are going to do that then put a min weight on it not a max. If they want to make it heaps heavy then let them. It'll just put them at a disadvantage. ;)
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Post by cooter »

i had a design floatin around my scon for a while involving a 3cyl charade motor and box with the diff welded and use 2 datsun irs diffs conected to each cv would work out bout 7: reduction
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Post by DAZ73 »

I also have been toying with this idea for about 3 months and i thought off sierra diffs, every zook has hilux gear anyway. you could use normal long travel shocks and weld or clamp a coil spring mount to it to take a rear moto spring, would even be easy to make 4 wheel steer due to low torque engine. you could use alloy wheels with 29" tyres ,already have good brakes weld the centre.cherade engine and box cheap as
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Post by Ingenious-Eng »

Toughnut heres one ready to go mate (not 4x4 though)
http://www.edge.au.com/buggies_ballistic.htm
Looks good though :armsup:
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Re: light weight class buggy

Post by r0ck_m0nkey »

bogged wrote:
toughnut wrote:Use a motorcycle engine like an XR650
how do you reverse?
Pick it up, move it to where you want it and facing the right direction and away you go.
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Post by toughnut »

Ingenious-Eng wrote:Toughnut heres one ready to go mate (not 4x4 though)
http://www.edge.au.com/buggies_ballistic.htm
Looks good though :armsup:
Yeah thats sort of what we were thinking. I'll have to put a rule in to only have one wheel per corner :D
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Post by "CANADA" »

toughnut wrote:
Ingenious-Eng wrote:Toughnut heres one ready to go mate (not 4x4 though)
http://www.edge.au.com/buggies_ballistic.htm
Looks good though :armsup:
Yeah thats sort of what we were thinking. I'll have to put a rule in to only have one wheel per corner :D

That thing is huge tho :P
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