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Front spindle diameter
designer - 10/5/19 at 02:17 PM

I'm not a structural engineer, and I know that most cars have large diameter front spindles, but is 11mm a big enough diameter for a small lightweight car?

AdamR20 - 10/5/19 at 02:30 PM

Sounds a bit small to me, especially if that is the diameter at the upright!

russbost - 10/5/19 at 02:32 PM

To answer that you'd need to know how lightweight & what sort of grip or extreme forces are likely to be exerted, how large/wide are the wheels etc etc

rusty nuts - 10/5/19 at 04:18 PM

11 mm is about the size of pushbike spindles, not sure I would want to rely on them holding a car up

steve m - 10/5/19 at 04:43 PM

I had 13mm spindles on a downhill cart, (pushbike wheels) and still thought I could of needed larger spindles

imho 11 mm, is for a toddlers trike

steve

nick205 - 10/5/19 at 05:54 PM

My push bikes have 10mm diameter axles. Strong enough for on and off road use, but no way I'd consider that diameter for a car.

Are you using parts from a donor vehicle and if so which one?

Are you fabricating the parts to your own or someone else's design, again if so can you share more details with us?

russbost - 10/5/19 at 05:56 PM

My point was really are we actually talking about a car, in which case way to small or are we actually talking about something like a cycle car?

paulc - 11/5/19 at 03:01 PM

As another data point, the spindles on my motorbike are 20mm at the front, ans 17mm at the rear.

And they are supported at both sides of the wheel.

nick205 - 13/5/19 at 08:44 AM

quote:
Originally posted by paulc
As another data point, the spindles on my motorbike are 20mm at the front, ans 17mm at the rear.

And they are supported at both sides of the wheel.



Good point - my Ø10mm push bike wheel axles are also supported both sides of the wheel either by the front forks or the cycle frame at the frear.

Motor car spindles are typically only single sided so need to be greater diameter/stonger.

(As above, assuming we're talking about motor car spindles)

nick205 - 13/5/19 at 08:48 AM

Mountian bike (push bike) axle diameters have increased in recent years up to Ø13mm+. With the aim of increasing rigidity of the assembly.

To add to this, I believe this is where front suspension forks have increased in travel length and designers are aiming to stiffen things up a bit at the point where the wheel attaches to the sliding section of the front fork. Equally the fork manufacturers have and are increasing the diameter of the upper (static) and lower (sliding) suspension forks, again to increase rigidity. The goal being to allow the suspension elements to work better with less mechanical flex around them.

[Edited on 13/5/19 by nick205]