Jump to content
Sign in to follow this  
Wetman

Wheel sizing for a thickie

Recommended Posts

When a wheel size gives an offset of say 6mm, what exactly does that mean? does that mean it will sit 6mm further off the axle than a standard wheel? IE giving you a further 12mm track width? or have I got that completely wrong?

Share this post


Link to post
Share on other sites

On real cars 0 offset means the mounting face of the wheel is exactly in the middle of the wheel.

Usually a postive number means material is added to the mounting face, so the mounting face is closer to the inside of the wheel, this has the effect of pushing the wheel further out of the arch. A negative offset means the mounting face is closer to the outside rim of the wheel, thus the wheel out move in to the arch (compared to 0 offset).

Another term that doesn't seem to be used in RC is backspace, this is the distance from the back edge of the wheel to the mounting face. Imagine a ruler placed across the back of the wheel and then another going from mounting face to the first ruler, whatever measurement is shown on the second ruler is the backspace. You can think of it as "space in the back".

  • Like 2

Share this post


Link to post
Share on other sites

cheers. That makes it clearer, although I`d heard the term offset in relation to 1:1 cars I`ve never heard the term backspace

Share this post


Link to post
Share on other sites
4 hours ago, Mark_C said:

On real cars 0 offset means the mounting face of the wheel is exactly in the middle of the wheel.

Usually a postive number means material is added to the mounting face, so the mounting face is closer to the inside of the wheel, this has the effect of pushing the wheel further out of the arch. A negative offset means the mounting face is closer to the outside rim of the wheel, thus the wheel out move in to the arch (compared to 0 offset).

Another term that doesn't seem to be used in RC is backspace, this is the distance from the back edge of the wheel to the mounting face. Imagine a ruler placed across the back of the wheel and then another going from mounting face to the first ruler, whatever measurement is shown on the second ruler is the backspace. You can think of it as "space in the back".

You have some good info there, but you have it the opposite way around.

- offset widens the track. + offset narrows it.

There are 3 axes, X, Y & Z.

All based on the centre line.

Further away from the center line is -, closer is +

Share this post


Link to post
Share on other sites

I think you're mistaking the terms "negative offset" and "postive offset" with the actual measurements.

ideas-of-backspacing-to-offset-chart-lov

 

26mm +6mm offset, notice how far back the mounting face is, this would widen track because the outside lip of the rim would be a long way from the mounting hub.

https://www.modelsport.co.uk/hpi-work-meister-s1-wheel-green-6mm-offset-2pcs-/rc-car-products/375287

111091_01.jpg

26mm 0mm offset, the mounting face is visibily forwards compared to the +6mm ones.

https://www.modelsport.co.uk/hpi-work-meister-s1-wheel-green-26mm-0mm-os-2pcs-/rc-car-products/383040

113095_01.jpg

9mm version moves mounting face even further back, widening the track more: https://www.modelsport.co.uk/hpi-work-meister-s1-wheel-green-9mm-offset-2pcs-/rc-car-products/376425

111100_01.jpg

Technically you could call this 6mm and 9mm negative offset, but wheels are not advertised in that way - just simply "6mm offset", hence what I said.

This is why backspace is far more simple :)

 

  • Thanks 1

Share this post


Link to post
Share on other sites

Centre lines are true.

I stand by my explanation. B)

Marketing personnel are not engineers. If they market their products correctly, there will be no confusion. :)

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  

×
×
  • Create New...