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[KrazyEd]

Congratulations on the progress. I haven't viewed this thread since before you ran the bike.
I was looking through some of my old time slips to see if there was something similar
for a projection. The attached is for two cars with similar 330 times to yours. Your slip shows
a gain of only about 8 mph for the last 1/8 mile.
The left lane ( 506 ) is my car which is a turbocharged Buicik.
I believe that the right lane was a turbocharged Honda CRX. Given the light state of tune
and gearing that you had at the time, Gearing alone should bring you to at least
low 12s. with a trap speed of between 100 and 105 mph. Stronger tune, harder
launch should put you closer to mid to low 11s. I wouldn't be surprised to see
you running in the 10s once all sorted out.  Assuming that the chassis feels solid at that speed.
Once in that range, you will probably be back to being speed limited by the gearing.
I haven't seen a lot of 1/4 mile times for the Zeros, but, from THIS web site, your bike seems
to already be faster than a stock S.

http://www.zeroto60times.com/vehicle-make/zero-0-60-mph-times/

You are right at the National NEDRA 1/8 record set by Jeremiah Johnson in 2014. 1/4 mile record at the time would probably have been gearing limited as well.

http://www.nedra.com/record_holders.html

[Doctorbass]

UPDATE!!:

Last Sunday i have finished building my wheelie bar ( and YES at 70%+ power the front wheel lift!)  and tested it on teh  dragway!

Here are all my run of 18 september with various Power limit so you can see the progression.

The most significant difference is the shift from 50% to 75% power witch droped my 1/4 time by 1.5s !!!

warming up run( first run): 14.09s at 50% power
next run at 75% power: 12.52s
third run still at 75% power: 12.46s
4th run at 85% power: 12.29s ( I was racing against a GSX witch did 12.56s)


Incressing from 50% to 75% reduced by 1.5s (not enough power to meet top speed... ( the 50% power limited max speed ))
incrasing from 75% to 85% reduced by 0.2s.. here, 10% more reduced by 0.2s
if that relationship is still in the linear region, i could expect to reach the high 11 with 100% with the actual gearing... BUT... the is limited speed due to the stock actual low speed gearing. I will make a change and replace the rear 132T by the 98T witch will in theory raise top speed to 132mph is that relationship is linear but we know it is not and power will limit this value to lower result..

After a total of  7 runs(4 good and 3 bad)  to 670Amp (75C rate) the battery was about 45 degree C only!

I got peak power to 48kW running only on 22s while the Zero normally use 28s.... Yes a little 9Ah battery gave me the 48kW !


here are the numbers of my best run witch was at 85% power ( at 90% i still get cut out )
0-60ft: 1.68s
0-330ft: 4.63s
1/8mile: 7.3 @ 87.4mph
1/4mile: 12.2@92mph
max power limit was set to 85% and gear was set for torque and not speed.(132T and 30T)
From what i know THAT IS THE QUICKEST EXISTING ZERO !... from what i know.. MPC-G class of NEDRA has now 12.2s ! next step is to modify the gear ratio, but today i wanted to know what is the max i can get out of the rear 132T. Next time i'll install the 98T. and 200 T belt. The first half of the 1/4 is very good but the second half my aceleration is very low... So gaining top speed with the faster gear ratio and raising power to 100% i should be able to keep the first 1/8 in the mid 7s but will get in the low 11s or even high 10s with better top speed to about 110-115mph


The link to the VIDEO is after these pics







https://youtu.be/iVMPBnfhukM

Doc

[KrazyEd]

Give 'em hell Doc

[Frank]

Good work Doc - waiting to see results after your next mods...   

[nigezero]

Massively impressed Doc, keep at it!

[protomech]

here are the numbers of my best run witch was at 85% power ( at 90% i still get cut out )
0-60ft: 1.68s
0-330ft: 4.63s
1/8mile: 7.3 @ 87.4mph
1/4mile: 12.2@92mph
max power limit was set to 85% and gear was set for torque and not speed.(132T and 30T)
From what i know THAT IS THE QUICKEST EXISTING ZERO !... from what i know.. MPC-G class of NEDRA has now 12.2s ! next step is to modify the gear ratio, but today i wanted to know what is the max i can get out of the rear 132T. Next time i'll install the 98T. and 200 T belt. The first half of the 1/4 is very good but the second half my aceleration is very low... So gaining top speed with the faster gear ratio and raising power to 100% i should be able to keep the first 1/8 in the mid 7s but will get in the low 11s or even high 10s with better top speed to about 110-115mph

Wow! 12.2 in the quarter at 92 mph is a weird result for sure

I think in the quarter mile you will see much better performance with the 98 tooth.

I'm curious as to how a 3 brick SR would perform.. I don't think it would do better than this, even with a light rider.

[KrazyEd]

Looks like your numbers are pretty close to what I projected.
If you still run out of gear with the 25/98 sprocket combination, a 98/30 setup
should give you a top speed in the neighborhood of 130 mph. Should be a killer
ride if able to handle the load.

( rpm * tire diameter ) / ( gear ratio * 336 ) = MPH

Congratulations Again.

[Doctorbass]

thanks guys! I am proud about that result, but i have some margin so i want to show you better performance again!

Next will be to replace the 132 by the 98 T.. i have all 25, 28 and 30T gear too and i calculated all possible match and the 28/98 seem teh best trade off to not sacrify the 0-60ft too mych but improove speed.

I will also play with the POWER limit table in DVT.. my actual curve is not  optimized  and i get cut out with overcurrent  fault when i go over 85% current.

I have found very interesting document about how to optimize the motor with sevcon... i will also have to optimize ki and kp PI... well some stuff you dont have to mess with when using brushed motor.. lol

6.6. Power Limit table The power limit table 0x4611 is used in exactly the same way as in the flux vector software. The peak torque in this table should match the motor peak torque value set in 0x6076.  It was found on early applications that the power limit table if not known could be derived on the application. This was done be setting the power limit values flat, i.e. all torques set to the maximum value. The vehicle was then driven and a DVT trace taken of the Iq current. The actual current would reduce naturally as the speed increases even though the reference was constant, the current controllers would be saturated. The Ke constant could then be used in the  relationship between torque and Iq in order to calculate what torque would result in the actual Iq currents measured. By doing this the reference current would then be very close to the actual achievable. 
In order to perform this procedure the current control fault will need to be disabled by setting Temporary DSP Configuration (0x4653,0) bit 0.  This setting is not persistent and will be lost after a key recycle.   

I hope that this sunday i will be abel to test again... i would love to have my own DYNO... !.. maybe i'll build it using my other 75-7 as a load and my 10kW load bank... well see..


Doc

[KrazyEd]

I know that Tesla increases power draw as they expand battery capacity.
Given that your battery pack is presently 13lbs. Would doubling the capacity
help your cut out issues? We used to figure that 10 lbs was equal to one horsepower.
Could be a worthwhile trade off.

[Doctorbass]

I know that Tesla increases power draw as they expand battery capacity.
Given that your battery pack is presently 13lbs. Would doubling the capacity
help your cut out issues? We used to figure that 10 lbs was equal to one horsepower.
Could be a worthwhile trade off.

Well the battery i'm using are way more powerfull than 10 pounds per hp. These are 100c Lipo sold by John Metric from Lonestar EV... it's like apple and orange compared to other battery.

That battery can sustain 680A at 85V no prob and can take more. There is no cutout due to battery as i dont have any error related to that in the controller the battery sag to about 3.4V and i have set the LVC to 3.0V


Doc

[MrDude_1]

instead of regearing for more mph, why not raise the voltage with another couple cells?
clearly you could put down more torque at the start line, so why dial that back for a few mph?

[Doctorbass]

yes, i will do that I still can add 6s ( 22V),  i will need to order these.. but that will be for the 2017 season as winter(snow) is arriving soon here.. and that is a quite convincing factor to stop the drag racing season


Doc

[Alan Stewart]

Way cool! This is using the stock motor with upgraded controller and battery, correct?

[Doctorbass]

Way cool! This is using the stock motor with upgraded controller and battery, correct?

The motor is a 75-7 from a 2013 S and the controlelr is a size 6 just like the SR use. Teh frame and the rest are from a 2012 witch is the lightest

Doc

[Frank]

Doc, you will be surprised at the performance increase in warmer weather.  I would think about some method of heating the cells (even for a Quebec "summer").  I use these same cells in my LSR bike; after one pass the pack would heat approx. 10F* and I would experience 10V less sag (96S pack).  Same thing on the drag bike: cool packs just don't perform as well.