The Mayor wrote:
Whilst on the subject of buses, has anyone noticed the number of AdelaideMetro buses that are crabbing? There are plenty of Torrens buses crabbing and a few SouthLink ones also especially the NL202's. However, some 18.280's seem to be crabbing also.
Anyone else noticed this odd bus behaviour? I am not very mechanically minded so could someone enlighten me as to what causes this and is it dangerous if left unattended?
I have noticed this with NL202's as well.
Crabbing is generally caused by a misalignment of the front and rear axles, that is, they are not both tracking in the same straight line.
Usually its due to worn suspension components that allow the rear axle to "float" and thus not be centered, or perfectly sitting in the rear of the chassis, thus meaning that slight steering input is required for the bus to go straight.
I wouldn't say its overly dangerous unless there is alot of steering needed to make the bus track straight. Still, they shouldn't be
crabbing at all. It can be fixed with a wheel alignment (or rear axle alignment). I'd hazzard a guess the reason they crab is from having the rear axle smashed into gutters which would disrupt the alignment. The most it really would cause is premature/uneven tyre wear.
TA3001 -
Crabbing is where a vehicle is slightly turned in the physical sense (ie the body is point off on a diagonal) but the direction of travel is still straight.