Timing for 80 metre standing start sprint

[mcnews]

Okay guys, we have a large collective pool of knowledge here and I am hoping somewhere amongst us is someone that has knowledge of accurate timing equipment.

Basically what I want to do is a repeatable standard acceleration test over around 80 metres of tarmac. To compare various models of ATV etc. in exactly repeatable scenario along an uphill tarmac slope on my property, a stig like standard acceleration test timed, speeds would be great also but times would do.

I am guessing I need basically a stopwatch/timer that accepts external inputs to trigger the start and stop.

Anyone ever set up this sort of rig?

[Buzz Box]

Sorry did you want to know what time equals what speed?

IE. X secs = Y km's

Or do you want help to set up a laser rig so you just drive past and it automatically tells you?

[Quicksand]

You might be able to get away with using GPS tests or buy something like a G-Tech Performance Meter though i have heard mixed reports on how accurate the G-Techs are

[mcnews]

What I am after is either a pressure strip or laser beam that trips the timer to start and then one at the other end that stops the timer. So basically an accurate 100% exactly repeatable way to measure the time it takes to go from point a to point b.

[Zoink]

FarmTek have a wireless, portable timing system for equestrian events that might suit your needs.
The timer and electric eyes run on batteries so could be set up anywhere.
http://farmtek.net/
http://farmtek-fti.com/download/brochure.pdf

[BPXR6T]

I use my GPS and an app called race chrono. I'd just average out a stack of runs.

[Scott]

Perhaps have a chat to your local Kart shop or look up Alfano on ebay etc. Very accurate timing, you would just need to add strips to the surface for start/finish and the Alfano will do the timing. Mychron is another popular brand.

With these units, you would need to fit them to each bike you test (rig up something quick/ish).

[mcnews]

Originally Posted by Zoink

FarmTek have a wireless, portable timing system for equestrian events that might suit your needs.
The timer and electric eyes run on batteries so could be set up anywhere.
http://farmtek.net/
http://farmtek-fti.com/download/brochure.pdf

I think that looks like the go mate. Exactly the type of thing I am looking for, bit more $ than what I wanted to spend that's for sure but that is the type of rig I need.
Edit - Damn, I just realised it was USD too! That makes it very expensive!
Hmmmm. It does look the goods though.

[AndrewR_AUII]

Jaycar light beam kit $11.95 x 2
http://www.jaycar.com.au/productView.asp?ID=KG9094

Couple of cases, Roll of cable, wire up output relays to a stopwatch.

Not the prettiest and easiest to set up - but cheap as.

[mcnews]

If you had the knowledge to set that up well you should start making the kits from those components and selling them. I can't even seem to find a stopwatch with external inputs. A friend of mine that does all the timing for the Aussie Superbike Championship etc. suggested some timing beams that he sources for about $120 each and wire them up to a stopwatch with external inputs which sounded like a pretty good set-up but I can't even find one of them!

[Scott]

I've made those kits before and 5m is a stretch, particularly outside in the elements.

[mcnews]

I was thinking the same myself. It looks as though the only real system is a 1.5k ask. But I have to be able to offer accurate and repeatable results, I mean like if I say Honda model x ATV does my acceleration test in x seconds and Yamaha model x ATV does it in ? seconds then obviously either Yamaha or Honda are not going to like it and I have to have something better than mates with stopwatches to back it up etc. GPS offerings etc. won't do etc. It has to be pretty damn accurate and 100% repeatable.

[Scott]

Ok, I got it. get a stop watch and tie it to a tree. Attach an 80m long piece of cable and tie it to the bike...

Or - use one of these:
http://www.laurels.com/stopwatch.htm

With two of these:
http://jaycar.com.au/productView.asp...Max=&SUBCATID=

Wire the two PE Beams in series and you're done.

[mcnews]

That might work, looking into it... Would need to run them off a generator I have or I could get the $30 optional adaptor kit and hook it up to a battery maybe... It also looks as though it would only display to the nearest second and not down to tenths etc.

[Scott]

You'd want the relays to latch for a couple of seconds so the bike can clear the beam cleanly. Nothing worse than having the tyre trip it to start, the beams re-connect after the forks and then break as the engine goes past. If these are not configurable, you can get cheap timer relays (~$20 probably) that would create the delay you would need.

I expect the problem may only exist on take-off though.

[mcnews]

Thanks for your help.

[Scott]

How did you go?