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[mistasam]

My attempts to break 4 seconds yesterday... still haven't been able to do it.  Any tips?

[tjax]

Sam, I am almost convinced the advertised 3.3 to 100KPH can only be achieved in a Vacuum!
 


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[mistasam]

Sam, I am almost convinced the advertised 3.3 to 100KPH can only be achieved in a Vacuum!

Yea, me too.  Is that how they do it?  No rider weighing it down, strapped to a dyno?

[Richard230]

Or the performance claim may be calculated from a mathematical formula.   

[tjax]

You mean actual speed - 1 second [emoji12] - my DSR arrives in NZ in three weeks, our combined weight should mean I will be lucky to get to 100 KPH in much under 5 (insert unit of measure here)!  Good for tying Sam - you might go quicker in a faster road - it is 40 Max on that road from memory - awesome road mind.  Try going down the Rimutakas - gravity could be your friend here!


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[mistasam]

Haha!  Good idea about going downhill 

I of course did this while the road was closed off for professional vehicle testing yadda yadda nothing illegal here.

[Doctorbass]

The sound of your motor is really strange.. it seem to have the sound that mine is doing when there is alot of humidity or rain.. and normally i notice a little loss of power when it ohappen.... maybe you could retry on a different route?

[mistasam]

The sound of your motor is really strange.. it seem to have the sound that mine is doing when there is alot of humidity or rain.. and normally i notice a little loss of power when it ohappen.... maybe you could retry on a different route?

Really??  Do you think something is wrong with my motor?  That's the kind of sound I've had since I bought it... so maybe something is up?

[KrazyEd]

Difficult to tell what devices you are using to measure your runs.
If using speedometer and stop watch, might be some lag.
Best way is at an actual track with timing equipment. Most
tracks don't really give zero to 60 times, just 60' times, then,
times at 330', 660' 100' etc. MPH at 1/8th mile mark.
Not sure if RADAR gun would be much more accurate.
As close as yours are showing, allowing for lag time,
and time to catch up, I would imagine that you are
probably already there. There are performance meters
that are designed to test acceleration that can be had
for pretty cheap. I used to use a G Tech pro years ago,
but, they have gotten a little pricey. Here is a link to
a Car and Driver article that tests the meters.

http://www.caranddriver.com/features/do-inexpensive-performance-meters-work-feature

Good Luck.

[mistasam]

I used a timer in Adobe Premiere lined up with the video, so it should be accurate.  I have a feeling something else is going on.

[yhafting]

My attempts to break 4 seconds yesterday... still haven't been able to do it.  Any tips?

I remember having read that the 3.3s for 0 to 60 was done with a rider of 6? kg...

First 60MPH is 96,56 km/h =26,82 m/s, going to 100km/h will take longer time.

lets say they used a 62 kg driver for that giving a total weight of 250kg
this gives a total Energy (not counting drag) spent of E=(mv^2)/2 = (250* 26,82^2)/2  = 89,93kJ

As far as i know the bike does lash out more power at 100km/h compared to lower speeds, so that may cancel some of the power wasted on drag- which lets us assumeclose to constant power spent on acceleration. Given linear power output we have 89,93kJ/3,3s = 27,25kW power
To reach 100km/h you would need to be 45kg (not counting the extra drag for going faster) to reach 100km/h using the same energy.

a typical rider may weigh 82kg giving a total weight of 270 kg => v(3,3s) = 92,91 km/h
at 100kmh he+bike will have 104,17kJ Energy.
Thus it will take approximately 104,17kJ/27,25kW = 3,8s to reach 100 km/h for an 82 kg rider.

Now the question is how much difference is there between the total weight of the bike+rider used for achieving 3.3s on 0 to 60 and your bike with you on it?
Are you able to cause less drag than was present at the 3.3s attempt?
...
slightly above 4s for 0 to 100 seems quite nice in my opinion 

[mistasam]

Wow, thanks for the detailed breakdown, yhafting!  I didn't even think about how big of a difference 100km/h was to 60mph.  Next time I'll just change it to miles for a this test, just to make it easier.  I weigh 70-75kg so it should be close.  And yea, you're right about 4 seconds being fast.  Insanely fast!

My motor is definitely making some strange noises though, so I'll get it checked out before doing another run.  Thanks again everybody!

[MrDude_1]

You could always use a CAN to bluetooth-serial adapter and log the runs with your smartphone.
That would yield more accurate MPH numbers than the gauge or GPS and video.

[Doug S]

There are several drag-racing apps for smartphones which use GPS, the phone's g-meter, and perhaps other sources to get pretty good accuracy. I don't know specifically how accurate but I know the drag racers use them and are pretty happy with them. I use "torque" in my car and it has several timer-type functions, though I've never had any interest in timing my 180,000 mile old 528i.

[tjax]

I have used Harry's Lap Timer, integrates video, GPS and OBD data with great results...really good when in the track given a comprehensive database of tracks..


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