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My quest to make motorcycle riding that tad bit safer

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Re: My quest to make motorcycle riding that tad bit safer

#161

Post by GuinansEyebrows »

aziaziazi wrote: post #156
andrewflnr wrote: post #129

Earlier quoted context omitted.

I have a smiley face rendered in retroreflective tape on the back of mine. I figure it's both bright and triggers the very sensitive human visual system for detecting faces. It's hard to say how much it helps, especially since I put it on basically the same time I started riding at all, but I don't often have people tailgating me. ed: and it was only a couple bucks, that's nice.

Nice idea! Cars owner sometime use a "children inside" sticker. Won’t work for a solo bike obviously but wonder if some other messages might be effective like "Dad of toddlers", "I might be a cop", "vulnerable human"… the smiley is easier to read through.

heh, or you could join an OMC (outlaw motorcycle club) and get patched up * for an implied 'i will literally kill you if you get close to me'

* don't do this

Re: My quest to make motorcycle riding that tad bit safer

#163

Post by kazinator »

Engine braking with an internal combustion engine generates a vacuum in the intake manifold, because the throttle is closed while the pistons suck air.

(Performance cars sometimes have vacuum gauges to measure this. Aftermarket ones can be installed.)

A brake light could be rigged to activate past a certain a vacuum threshold. (There would be some false positives that are possibly not worth caring about.)

For all the engineering described in the article, I'm surprised it doesn't mention this possibility, if only to give reasons why it was discarded. (Maybe it's a bad solution; I have no ide!)

It seems that a vacuum-driven brake light could possibly have an advantage of kicking in faster than a motion detector, because it could trigger as soon as the revs are dropping with the throttle closed, before the clutch engages to actually connect the engine braking to the wheel.

I.e. blip-throttle before downshift -> vacuum kicking in / light comes on -> downshift completes, actual braking begins.

Re: My quest to make motorcycle riding that tad bit safer

#164

Post by garaetjjte »

WalterBright wrote: post #132

The issue with brake lights is they are binary on/off. It would likely be better if the brightness would vary by how hard the braking is. Like getting brighter and brighter and then rapidly flashing.

Brightness would be hard to discern in the sun. Cars have center stop light strip, it would be cool if amount of illuminated segments would be proportional to deceleration. Probably not legal though.

Re: My quest to make motorcycle riding that tad bit safer

#165

Post by sublimefire »

Good example how to push forward and do the thing.

Otherwise, is it me or the info on the product page is a bit dry. No size specs, no instructions, not enough pics. It is like the last step to convert is not fully complete yet.

One of the issues usually is to make sure the part is compatible with the bike as otherwise you need to spend money to get it and then “try it”. The suggestion with tge pictures how to put it would be useful as well.

Re: My quest to make motorcycle riding that tad bit safer

#166

Post by blendergeek »

jfim wrote: post #131
jeffbee wrote: post #107

Earlier quoted context omitted.

As you may be aware, the US is a confederation of states. The type of light that flashes several times at the initiation of braking is specifically authorized by the California Vehicle Code, and perhaps in other states.

Do you have a reference as to where it's allowed in the CVC? FMVSS section 108 table I-c specifies this for the stop light: Steady burning. Must be activated upon application of the service brakes. When optically combined with a turn signal lamp, the circuit must be such that the stop signal cannot be activated if the turn signal lamp is flashing. May also be activated by a device designed to retard the motion of the…

California Code, Vehicle Code - VEH § 25251.5

(a) Any motor vehicle may also be equipped with a system in which an amber light is center mounted on the rear of a vehicle to communicate a component of deceleration of the vehicle, and which light pulses in a controlled fashion at a rate which varies exponentially with a component of deceleration.

(b) Any motor vehicle may be equipped with two amber lamps on the rear of the vehicle which operate simultaneously with not more than four flashes within four seconds after the accelerator pedal is in the deceleration position and which are not lighted at any other time. The lamps shall be mounted at the same height, with one lamp located on each side of the vertical centerline of the vehicle, not higher than the bottom of the rear window, or if the vehicle has no rear window, not higher than 60 inches. The light output from each of the lamps shall not exceed 200 candlepower at any angle horizontal or above. The amber lamps may be used either separately or in combination with another lamp.

(c) Any stoplamp or supplemental stoplamp required or permitted by Section 24603 may be equipped so as to flash not more than four times within the first four seconds after actuation by application of the brakes.

https://codes.findlaw.com/ca/vehicle-code/veh-sect-25251-5/

Re: My quest to make motorcycle riding that tad bit safer

#167

Post by sokoloff »

bell-cot wrote: post #89
foobarian wrote: post #56

Earlier quoted context omitted.

Tbh I find my manual gearbox car not able to slow very hard at all with engine braking. However it's admittedly not a Diesel engine.

Having driven (and engine braked) both diesel and gas manuals - yes, a diesel is much better at slowing "very hard". Beware of doing that if someone is close or inattentive behind you. With either one, any need-to-brake situation gets more complex - you need to decide "brake pedal, engine, or both?". But I'm not driving manuals because I want driving to be super-simple.

Interesting. I found my diesel Mercedes to not have much engine braking at all (which I attributed to the lack of a throttle plate or any throttling of airflow) as compared to similar size and weight gas cars (which have a throttle plate in the intake).

Re: My quest to make motorcycle riding that tad bit safer

#168

Post by gus_massa »

braunshedd wrote: post #71

When I was commuting daily in the SF fog, I discovered that putting on of these [1] on my helmet did wonders to keep cars further off my tail. It moves the brake light up to eye level for people in SUVs and also triggers on engine braking. Wish it were cheaper, but was a worthwhile investment for me. Also, consider looking into airbag vests if you ride regularly. Also expensive but (supposedly) make a huge difference…

Does it use an accelerometer to turn on?

Is it safe in case of an accident? The helmet is quite round, and the not round shape may be a problem.

Re: My quest to make motorcycle riding that tad bit safer

#169

Post by sokoloff »

asdsadasdasd123 wrote: post #147
_ea1k wrote: post #10

TBH, I'm surprised this isn't already common. It is very similar to what EVs do, due to the relatively high regenerative braking.

Im surprised new cars dont just go off of a gyro decel reading, don't modern cars already have a gyro?

An accelerometer would be a far better sensor than a gyro here. (You want to measure linear acceleration not angular velocity.)

Re: My quest to make motorcycle riding that tad bit safer

#170

Post by haiku2077 »

beloch wrote: post #90
braunshedd wrote: post #71

When I was commuting daily in the SF fog, I discovered that putting on of these [1] on my helmet did wonders to keep cars further off my tail. It moves the brake light up to eye level for people in SUVs and also triggers on engine braking. Wish it were cheaper, but was a worthwhile investment for me. Also, consider looking into airbag vests if you ride regularly. Also expensive but (supposedly) make a huge difference…

Motorcycle fatality rates have been trending upwards, not downwards[1]. Brake lights on helmets may illuminate one of the culprits: An ever increasing number of American trucks with poor visibility. Sitting on a bike, you're even shorter than a pedestrian and more likely to be completely out of sight. Perhaps its time to start regulating for better visibility, as Europe has done. [1] https://www.iii.org/fact-statisti…

When I am sitting on my motorcycle I am taller than most people's sitting position in their trucks. While filtering I can look down into their vehicles and see what they're doing on their phones.
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