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It was actually 20K sterling, however that converted at the time.  Electric Motorsport sold the winning bike as per the rules of the open class race.  Thankfully, our rider Chris Heath who is an Isle of Man resident was assigned care taker of the motorcycle so it still gets a lot of exposure in the UK.

The Native TTXGP as we call it, is toured to shows and races all around the UK.   Usually for display, demonstration, and parade laps.
It often does the IoM drags where it has beaten several two strokes, and the team Agni bike at least once.   

Still wish I had it. It was my daily driver for at least two years.
 

63 MPH is what the bike is geared to for the best acceleration and range.  The bike can be geared anywhere between 45 - 70 mph however gearing to 70 mph will decrease acceleration and range some.  Changing the dive gear for higher speed is not hard however it is not good to gear up all the way until the motor has had a chance to break in.   

TK

Hi my name is TK,

I am Electric Motorsport and I am going to see if I can help shed some light on Gridnack's issue. 

Electric Motorsport GPR-S Recalled the on-board speed chargers on 24 of the first 100 bikes it sold.

The reason for this recall was because the 1.5 kW on-board charger kept popping its fuse.
All of these 24 chargers have been replaced.  If someone was unfortunate enough to experience one of these blown charger fuses they would not hear the audible charger fans running or see the green LED charge light. Their batteries would not be getting a charge.  If they tried to ride the bike uncharged the controller would immediately hit low voltage cut back and current limit them to half speed (35mph) until the vehicle would eventual come to a stop.   Luckily most customers were able to have the replacement charger installed and the battery pack was not effected.  Some however ended up damaging some battery cells.   Electric Motorsport had these customers batteries replaced free of charge.

BALANCING

The solid state BMS on the Electric Motorsport GPR-S shunt balances about 100 milliamps.  That is equal to 2.4 Ahr of balancing over a 24 hour period. This is fine for balancing a matched and pre balanced pack of LFP batteries but if one or more cells are being replaced in a pack it can be a different story.   When changing cells in a series pack it is possible that the new cells are not at the same state of charge as the rest of the pack.  we recommend if changing a cell in a Lithium Pack either parallel balance the pack first with the new cells or install cells that have somewhat equal state of charge.   If not what Gridnack is experiencing can be the result.

   If a fully charge battery cell of 50Ahrs is put into a pack that is depleted to 20% state of charge the new cell will be holding 40 Ahr more capacity then the rest of the pack.  This is BAD because the charge will irremediably turn of when the charged cell hits max voltage and the rest of the pack will not charge that is until the BMS bleeds down the newly installed cells to match the rest of the pack.  This however would take an abnormal long time

The math goes like this

40 Ahrs  / 100 milliamps  = 400 hours to balance.

When we heard the installer at a local electric vehicle repair shop put fully charged replacement cells into a depleted pack and reset the BMS we immediately new the customer was not going to be happy with the fact that they would have to wait so long before they could ride their bike.   If it was in our shop we would have parallel balance the new cells prior to installing avoiding such a abnormal long balance time.


VOLTAGE AND STATE OF CHARGE METERS FOR LFP BATTERIES.

Standard state of charge meters do not work very well for LFP batteries.   The reason is that the voltage drop is not as linear with state of charge like Lead Acid batteries are.   This means most state of charge meters for LFP would stay almost full up to about 10% state of charge and then would drop like a rock.   This is why we put a Cycle Analyst on every  Lithium bike sold.   The Cycle Analyst as explained in the GPR-S Owners Manual reads both Amp hours used and watt hours used.  Both of which can count down state of charge like a precision instrument to the thousandths of a percent.   If the battery pack ever gets to low the controller also has a limiter that cuts back power and speed along with a distinct low pitch current limiting sound.   Riding in low voltage current limit is not good for the batteries.   This is the same with every Electric Motorbike or Scooter on the Market.   Gridnack was complaining there was no RED danger you are low light.   This is somewhat true.   A new rider may not recognize the sound of the low voltage power cut back.   They may be just wondering why am I only going half speed.  Indeed there is a red warning light Alltrax puts on the controller itself but the rider can not see the controller under the fairings.   that is why we now have a fiber optic cable upgrade for the GPR-S that goes from the controller LED to the dash so people can see the RED LED low voltage light that comes on simultaneously with the current limiting feeling and sound.

Hope this helps.


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