Taking speed bumps at an angle.

Joined
May 10, 2005
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2,731
Location
Toronto, Canada
I was riding my motorcycle early this morning on residential streets and came across numerous speed bumps. It never occured to me before but you can go faster over a bump if you approach it at an angle. With no traffic around I was riding over the bumps at a 45* angle and was going over the bumps quite a bit faster than I normally do.

I would have stopped doing it if I saw a cop because he could write me up for weaving all over the road or even dangerous driving if he was in a bad mood.
 
You make the angle of the bump shallower when you do that. On narrow bumps I'll weave the truck slightly so the tires don't hit at the same time. Alternative is to hit them fast and make the suspension cycle without moving the body. Washboard dirt roads work the same but it's rough until you hit the right speed.
 
I always thought one approach to making a car more stable over road imperfections perpendicular to the direction of travel was to make the wheelbases different left to right. This would make the suspension compressions and deflections unequal in time decreasing the reaction of the vehicle. The Renault 16 had that feature. 'From Wikipedia', One peculiarity of the R16, and later Renault 5, design is that the two back wheel axle shafts are not in-line. The left wheelbase is 70 mm (2.76 in) longer than the right wheelbase, to accommodate the transverse torsion bar suspension. This and the soft front seats gives the car a particularly smooth ride even over big bumps.

Renault.jpg
 
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MSF (motorcycle safety foundation) will teach that speed bumps, railroad tracks, and other straight obstacles should be approached straight on, due to the risk of kick-out at the angle. Obviously one can use an angle as long as the forces and frictions don’t overwhelm, just be aware that it *increases* risks against your favor when you come across that one speed bump that for some reason has washout or other difference you aren’t anticipating. i might also be inclined to practice lifting off the seat a little to let the bike work some as an additional skill.
 
"Messing around" with speed bumps in order to go faster seems like a fool's errand.

There likely is no standardization to the 'ramp angle'. If repaired, the leading edge had to have been patched with different materials (at least a different batch), rolled to a different surface finish and likely unstable compared to the older sections of the ramp.
 
I consider speed bumps to be a particularly ignorant means of speed control. They are an invention of the devil, designed to wear out your suspension faster, even when taken at or below the designated speed limit. Our village has 4 of them to encourage compliance with a 20mph speed limit. They are distinctly uncomfortable taken at 20mph in the car and never fail to raise my mechanical sympathy. I would say that I can take them at the full 20mph on my motorcycle and with more comfort especially if the bike is ridden as it should be, that is you ease your bum off the seat momentarily over the bump. It's never occurred to me to take them at an angle and often it isn't necessary. Either by rule or policy, speed humps in the UK rarely extend across the full width of the road. They either taper in severity towards the ends or stop short of the curb by a foot or so. I believe this is to allow pedal cycles to avoid the worst of the bumps. Where a pedal cycle can go, so can a motorcycle.
 
Add me to the hate speed bumps group. I think taking them at an angle is even more difficult on the suspension of a 4 wheel vehicle, downright dangerous on a 2 wheel.
 
speed bumps pffff. speed tables are all the new rage.
Most of the roads in Dallas are rougher than that thing. They're probably afraid of too many claims for bent wheels and suspension components, which some of the speed bumps here could most assuredly inflict. I wouldn't even slow down for a speed table if I was driving the Canyon.
 
Regarding safety of approaching at an angle, consider the following
1) Dry day, no water on the asphalt.
2) I am not speeding over the bumps. Normally I would do 20kph over them, now I am doing 30 kph taking them at an angle. It is not that big a deal to wipe out at 30 kph (and very minimal chance of that happening if you are riding sensibly) with no traffic around and you are helmeted.
3) Not once did I feel any loss of traction from the front wheel while taking the ramps at an angle.
 
I slo a bit (35 to 20 or so) but as said above, the end does not extend to the curb so only 1/2 an axel goes over.

I see 6 DPW guys on that instal or removal. That's 2X/yr. Replacement costs (of the 'table") not included = expensive.
Hope they choose well as that's our money being used. Slo dwn so as not to pay these costs. (I still dont see an example. The
Ohio vid never displayed for me).
 
Speed bumps are there for a reason. This is like recommending one doesn't follow the 20mph speed limit signs in residential areas.
I am not advocating speeding on residential streets. On most residential streets in Toronto, the speed limit is 40 kph and there has been a long standing proposal to lower it to 30 kph. I am fully in support of it. There are too many small animals getting killed on our streets and also the lower limit will discourage people cutting through residential streets.

I am not speeding, taking the bumps at an angle enables me to maintain a more even speed, but still under the speed limit.
 
#17 above, I'm widja!
"...I slo a bit (35 to 20 or so) but as said above, the end does not extend to the curb so only 1/2 an axel goes over...."
It's just abt the 'car' (or is it butt) trauma~
 
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