predator 95 pro

[GJW]

here is a buggy that i never get sick of looking at, this came off ebay in un-run condition for a very decent sum of money. i have fully rebuilt the car to clean up a few part's and to get to know what make's them tick one amazing ride that tub is just a work of art

feel free to add pic's of your own predator to my thread

[vintage racer]

Awsome car Garry,love that carbon tub,got a body for this baby?

[GJW]

thanks jame's, the bodies are impossible to find buddy but like most things they show up eventually would love to have a drive of this buggy so ill find a runner

[Mad Racer]

Very nice Gary.

I remember seeing one or two on the grass tracks in the U,K.

While they weren't that good in those hands i did see one that kicked all our butts . So they can be very good if prepped right i say.

[Lowgear]

So these came out in 95 I take it? It always amazes me because they look like something thats current. I always thought they were until I kept hearing them referred to as vintage. Way ahead of their time comes to mind to put it mildly. At least in the looks department if nothing else.

[GJW]

Very nice Gary.

I remember seeing one or two on the grass tracks in the U,K.

While they weren't that good in those hands i did see one that kicked all our butts . So they can be very good if prepped right i say.

thanks mark, what year did you see them run mate? would love to see some video

So these came out in 95 I take it? It always amazes me because they look like something thats current. I always thought they were until I kept hearing them referred to as vintage. Way ahead of their time comes to mind to put it mildly. At least in the looks department if nothing else.

this model is a 1995(serial number actually denote's year and build number) but the first came out in 1993, it had the same carbon tub(only 93/95) and are the coolest in my opinion.

[tamiyadan]

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[minichamps11]

Torque steer: That is what doomed the 10th Tech chassis .

some felt 10th had ripped off some of Schmacher's ideas.

10th had good ideas, but materials just weren't there yet as they are today.

great find

Interesting post, what did Ttech rip off from Schumacher? Was it the inboard suspension idea? I thought both companies took the idea from F1.

Would like to know more about the torque steer comment. I noticed my Pred X10 and even the latest X11 version have the motor on the same side as my original carbon tub predator from 1993, however almost all my other shaft drive buggies have the motors on the opposite side....

[tamiyadan]

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[minichamps11]

Not sure about your comments on the Predator chassis. For quite a while it dominated in the UK…although this was partly due to its efficient drivetrain, the chassis itself was agile and handled well if you could understand how to set it up correctly (and keep it in one piece for 5 minutes).

Torque steer can be an issue with shaft drive cars, however with off-road buggies it’s only really noticeable in the air where the torque reaction twists the chassis if you need to use the throttle to adjust for landing. My Lazer FS2 doesn’t show any kind of torque steer on the ground. However I disagree with your comment about shaft drive being better for on-road; touring car chassis’s are lighter, narrower and stiffer, plus generally run more powerful motors than buggies due to the high grip track/tyre combination they run on, and as a result will suffer from torque steer more than buggies. When I ran a TC3 on carpet I had horrendous issues with it torque steering. It's no coincidence that best current touring cars now run belts…..

To minimise Torque steer effects you need to do two things ...

1) Firstly keep the inertia & momentum of the prop / slipper assembly to about the same as the armature (rotor for brushless) ... remembering to account for any gearing between the two. My friend who helped develop the Predator asked Richard Weatherley about this in the early Tenth Technology days and (I quote) "he just smiled and said go and measure the weight of a typical 12x1 armature with a 23 too pinion on, then measure the prop assembly including both gears and the inner races from the bearings ... you will see why there is a 70 tooth spur on there”....so it was considered

2) You must have the drive system configured such that the armature / rotor (assuming only one gear mesh between them) rotates such that the rotational forces run AWAY from the centre line of the chassis, again assuming the prop is running along the centre line. Things get more complicated if it’s angled across the chassis. Look at the more modern shaft drive cars and you will see this to be the case for the Lazer and Durango ... all the BJ4 copies have this wrong!!! The Tamiya TL-01 you talk of was a basic low cost touring car chassis with the shaft drive down one side for the same reason my 1980's Thundershot did - the packaging of the bevel gears Tamiya use to use to take the drive from back to front, nothing to do with torque reaction!

The position of the shock absorbers (inboard or standing up) won't make any difference to torque steer. I agree that Predator style suspension leads to lower lever arm ratios, so a stiffer spring is needed to get the same setup as a “conventional” suspension design,but that’s the whole point, once stiffer springs are used the wheel rate (and that's all that counts in suspension design and tuning) ends up identical in both cases. Also the Predator suspension allows the shock pick up point to be optimized (it's right outboard, inside the wheels) as it's easier to package a turnbuckle link in the right place than a bulky shock absorber. It’s much more likely the chassis you drove was tweaked or the suspension / damper rod linkages uneven lengths side to side – this will cause torque steer-like effects.

Double deck composite chassis are no way as stiff as carbon tubs, plus they are much more susceptible to tweak. In the UK Atomic Carbon conversions have been very popular in the past few years (S2, S4, S44 etc). The carbon tub chassis is massively stiff in torsion and longitudinal flex, however recently there seems to have been a realisation that for the average racer on UK high grip tracks at least, a more flexible chassis makes a car more forgiving and easier to drive.

As for flexibility of tuning, you are incorrect, the Predator had many more options for tuning than any off-road car before it. The problem was a lack of understanding from racers who aren't technically minded. Here is a quote from an experienced professional engineer who helped develop the Predator with Richard Weatherley back in the 90's:

"Firstly the rocker design on the Predator was a rising wheel rate system so you could set the car up softer in terms of initial WHEEL RATE (although stiffer more progressive springs as the travel at the shock is short) and still have the stiffness to deal with the high speed loadings. A chassis that was soft enough for predictable initial turn in and small bump compliance but then stiffened up in roll to give good corner grip and stability without having to run crazy roll centres ... what a naff piece of engineering that would be!"

Chain versus belt versus shaft…surely this argument died off in the 1980’s? Who uses chain? I’m sure there hasn’t been a chain drive buggy released in the last 20 years. For the record, it’s only roller type (push bike style) chains that have an efficiency significantly higher than belts, and only then if they are kept perfectly clean and in good condition which is rarely going to be the case in an off-road buggy racing environment. Personally I’ve never seen an RC car with this style of chain. The last 4WD buggies to use chains (Optimas, AYKs etc) used a bent wire type of chain which was noisy, stretched easily and highly inefficient.

Engineering journals show that well designed belt, shaft or chain drives can all achieve efficiencies of 90% + , with roller chain’s being top of the list, followed by V belts then shaft drive. However I’d stand up and say that the efficiency aspect of RC buggy drivetrain design became irrelevant in the last 6 years with high capacity NiMhs, LiPos and intro of brushless motors. Not only that but shaft drive buggies with their sealed drive trains are arguably going to be more efficient than the best belt drive once it’s got a small amount of dirt contamination. The best sealed belt drive buggy I’ve owned is the Losi XX4, but even that eventually got a build up of dirt / belt debris on the pulleys.

[Charlie don't surf]

Your comment on the softer chassis being more forgiving couldn't be more true! Except during really high traction conditions when it can torque and then rebound-

[tim.sanderson]

Whether these cars drove crappy or awesome, one thing is for sure; they are a piece of art that anyone would love to have in their vintage collection!

[minichamps11]

Whether these cars drove crappy or awesome, one thing is for sure; they are a piece of art that anyone would love to have in their vintage collection!

Agreed, here's my '94 car and X10