Demon Tweeks bargain

[Man On The Clapham Omnibus]

This device from Demon Tweeks is very useful and at this price, good value IMHO.  

[johnjj]

Brilliant product, have used mine for years and have checked accuracy several times against other more expensive and sophisticated equipment.

Very easy to use.

John

[mpett]

I can't work out how it works from the pics.  Could someone explain?

Cheers

[Man On The Clapham Omnibus]

It's an almost frictionless plate that is free to move laterally on rollers on a static base. It is connected to a pointer which magnifies the amount of movement left and right and shows it as mm or degrees of toe. It depends on the assumption (correctly) that when, say, a wheel is toe'd in, its opposite number on the other side is equally toe'd in. Therefore both are trying to steer towards each other and because they cannot actually do so, they affect a sideways force on the road surface as you drive, thereby scrubbing the tyres. If one wheel stays on tarmac and the other is placed on something that permits this tendency to shove the road surface to one side to actually happen, then that tendency can be manifested in a slippage. Here's where the laterally sliding plate comes in. You put the Trakrite in front of your car's wheel - either side -  and make sure by eye that it is as parallel as possible with the direction of travel. You then, whilst NOT holding the steering wheel or braking, allow the car to roll as freely as you can over the plate. If the wheel on the plate is angled with respect to the major axis of the car (toe'd in or out) it will cause a controlled movement of the plate sideways to occur. This will read out as misalignment on the gauge's scale. Tweak the tracking a bit (and this is where it is not so good as garage equipment because you have to use trial and error) and test again. There is no need to know what the ideal setting is, because it is a dynamic test Gunson says, simply set it until there is no toe in or out. The major problem, other than needing to adjust by trial and error, is finding a level smooth surface large enough to do the test. I use the car park of a leisure centre near my house and I do get some funny looks.

For quick checks 'on the hoof' it is excellent and seemingly accurate. I bought mine because I have had almost 100% bad experience with grease monkeys at tyre centres trying and failing to adjust my tracking. With a bit of maths (trigonometry and geometry) and knowledge of the thread pitch on your track rod ends, you can calculate how much to adjust the tracking and get it pretty well right first time.

All in all, a Good Buy  

[Eccentric_Rich]

First time I've ever seen Demon Tweeks and Bargain in the same sentence!

Richard