Alta kit bike

[TonyWilliams]

Well, I personally think this endeavor was a very good exercise. Could a Alta v2.0 still be produced? Of course. It just wouldn’t be with SOME of the existing Alta hardware.

I’d say that a lighter, better frame could be developed. Building a battery with commodity cells isn’t rocket science. Off the shelve BMS is available. The cooling issues have several possible solutions.

Electric motors aren’t rocket science, either. I think there are significant weight and efficiency improvements possible for the inverter. Better cooling of the motor (like Tesla) is possible.

The off-aboard / onboard charging system could EASILY be improved. Obviously, the software is a big deal, but there are lots of folks who could produce software.

The bars, wheels, tires, brakes, chain, sprockets, grips, levers, throttle, suspension, etc, are all “off-the-shelf”.

So, I propose a “kit bike”.

 

[RRR]

Agreed that it should be highly doable. And probably not very hard to achieve incremental (10, 20% ?) improvements in weight and range, respectively. BUT, making it street legal (EXR analog) might be a logistic hassle, as could be the logistics of software updates and support. An equivalent with 100 mile range, convenient charging, reasonable expectation of parts/maintenance... Whoever achieves that gets my $15k tomorrow.

 

[querlenker]

Well, I personally think this endeavor was a very good exercise. Could a Alta v2.0 still be produced? Of course. It just wouldn’t be with SOME of the existing Alta hardware.

I’d say that a lighter, better frame could be developed. Building a battery with commodity cells isn’t rocket science. Off the shelve BMS is available. The cooling issues have several possible solutions.

Electric motors aren’t rocket science, either. I think there are significant weight and efficiency improvements possible for the inverter. Better cooling of the motor (like Tesla) is possible.

The off-aboard / onboard charging system could EASILY be improved. Obviously, the software is a big deal, but there are lots of folks who could produce software.

The bars, wheels, tires, brakes, chain, sprockets, grips, levers, throttle, suspension, etc, are all “off-the-shelf”.

So, I propose a “kit bike”.

Hi, did you have the parts open and tooked a closer look? I don’t think it’s that easy. Yes you could save a small amount of weight at some places, but you will add it on others, like radiator/fan etc. .
The battery isn’t that easy too. For the mx use you won’t build lighter than 30kg in the next years. Therefore you need cells improved significantly in both directions, energy density and power density.

And a kit bike will be more a compromise depending on how many available oem parts you use.

I don’t say it’s impossible, I just say it’s not easy and not cheap. And without meaning it offensive, I have heard such sentence a lot. All those bikes/builds newer made it on the track.

 

[ninety3mx]

Hi, did you have the parts open and tooked a closer look? I don’t think it’s that easy. Yes you could save a small amount of weight at some places, but you will add it on others, like radiator/fan etc. .
The battery isn’t that easy too. For the mx use you won’t build lighter than 30kg in the next years. Therefore you need cells improved significantly in both directions, energy density and power density.

And a kit bike will be more a compromise depending on how many available oem parts you use.

I don’t say it’s impossible, I just say it’s not easy and not cheap. And without meaning it offensive, I have heard such sentence a lot. All those bikes/builds newer made it on the track.

Absolutely agree!! The ones who are willing and fearless to take a closer look inside (maybe also risk something at a time) will always find ways to improve things. I think within this community we shouldn‘t be worried too much. Thanks to everyone taking part on this mission and @Philip for giving us a platform! Alta is not dead.

 

[privateer703]

You could always just send it to China. You'll have a perfect copy that gets half the range, costs 1/4 and only blows up 1 one 5 times.

 

[snydes]

You could always just send it to China. You'll have a perfect copy that gets half the range, costs 1/4 and only blows up 1 one 5 times.

And shipping for less than you could rent a U-Haul for!

 

[TonyWilliams]

Hi, did you have the parts open and tooked a closer look? I don’t think it’s that easy. Yes you could save a small amount of weight at some places, but you will add it on others, like radiator/fan etc. .
The battery isn’t that easy too. For the mx use you won’t build lighter than 30kg in the next years. Therefore you need cells improved significantly in both directions, energy density and power density.

And a kit bike will be more a compromise depending on how many available oem parts you use.

I don’t say it’s impossible, I just say it’s not easy and not cheap. And without meaning it offensive, I have heard such sentence a lot. All those bikes/builds newer made it on the track.

I never mentioned anything about fans and radiators. That’s probably not a good idea, but you’re welcome to try that technology... it’s been around for about a 100 years. But, who knows? Maybe that proves to be the best solution. It could be optional.

With the exception of charging, I didn’t claim anything was “easy”. My company is in the Electric Vehicle charging business, so yes, I would find that charging improvements would be “easy”. I think the current setup is sad, to be honest.

The frame would be “easy” for any mechanical engineer. Literally, one guy. Design, prototype, test, redesign, build. Easy. Maybe it goes through several iterations. What it wouldn’t be is compromised because Alta didn’t have access to the correct machine tools for the job. I could design and fabricate a frame for an Alta v2.0 kit bike.

I don’t share your pessimism about battery technology, and the current cell technology is available to ANYBODY. The Panasonic and Sony 18650 cells are commodities. The battery is several things currently -

1) hundreds of cells
2) modular cell construction
3) a box to put it in
4) electronics to manage the cells
5) missing - a logical cooling system

Literally ANYBODY with basic skills in the required fields could build this battery, including me.

Only a couple things left... the motor and 3 phase AC inverter. I personally do not have specific skills in motor or inverter design, but lots of folks do. I propose several fundamental changes from the current bike to lower the rotating mass, cool the motor, and potentially lighten the assembly. There are oodles of inverter designs out there... no rocket science required.

The topping on the cake is the software to control it all. Clearly, there are lots of folks who can do that (not me).

None of what I’m suggesting are replacement parts for the current bike. It would all be improved parts for an even more capable bike. But, all the current triple clamps, forks, suspension, wheels, brakes, bars, sprockets, chain, etc, would ALL directly interchange.

 

[bluefxstc]

Is there an issue with motor or inverter cooling? I thought the cooling issues were in the battery since it does not have active cooling like the motor and inverter.

 

[snydes]

Not really interested in a complete redesign myself, just support for existing platform.

 

[TonyWilliams]

Not really interested in a complete redesign myself, just support for existing platform.

Yes, obviously, existing owners want support for their bike. I own the bike, also. There’s a market for that, but obviously, limited to a very small number of machines. It seems like lots of folks are stepping up to support the bikes.

 

[TonyWilliams]

Is there an issue with motor or inverter cooling? I thought the cooling issues were in the battery since it does not have active cooling like the motor and inverter.

Yes, the battery hits limits that are programmed into the BMS to prevent degradation or damage to the cells.

The cells have the most POWER (kW) and energy (kWh) when they are hot, like at 50-60C. Those same cells have the longest life and least energy / power when stored at -20C. You can see why manufactures who provide warranties and want happy customers for more than a race will limit the cell temperatures to 45-52C typically. Somewhere in that range, the current Alta BMS limits power. Very few people are operating motorcycles in extreme cold, therefore heaters wouldn’t be normally needed. But, there should be lightweight heaters powered off board for charging the bike, or heating the cells prior to a race.

The only way to protect the cells from high heat without a proper cooling system is by limiting power (or shutting down altogether... super dangerous for motocross and supercross). The current bike does not have a proper cooling system... it can only limit power or shut it down.

The motor may be able to be made smaller and lighter if it were cooled in the manners that Tesla uses. Inverters and motors should be able to handle more heat than battery cells, which normally would require two separate cooling systems.

 

[querlenker]

...The only way protect the cells from high heat without a proper cooling system is by limiting power (or shutting down altogether... super dangerous for motocross and supercross). The current bike does not have this....

It does, it reduces power. It’s just depends on skills of rider and terrain, how fast or if you get there.

 

[TonyWilliams]

It does, it reduces power. It’s just depends on skills of rider and terrain, how fast or if you get there.

We aren’t disagreeing... without a proper cooling system, the ONLY options are reduce power or shutdown.

The number 1 criteria is ambient heat, and solar radiation is probably close behind. Even a bike not being ridden could hit the thermal limits.

Yes, a warm cell, and heavy use (either riding or charging) may also hit the thermal limits.

Hence, why virtually every vehicle manufacturer in the world that produces a battery electric vehicle, also includes a proper heating and cooling system for the battery. Alta does not (because it’s lighter and cheaper).

 

[TonyWilliams]

Agreed that it should be highly doable. And probably not very hard to achieve incremental (10, 20% ?) improvements in weight and range, respectively. BUT, making it street legal (EXR analog) might be a logistic hassle, as could be the logistics of software updates and support. An equivalent with 100 mile range, convenient charging, reasonable expectation of parts/maintenance... Whoever achieves that gets my $15k tomorrow.

Most states have a simple way to register homebuilt vehicles. You could use the title from an existing Alta that happened to need repairs (the repairs could be replacing everything except bits “forks forward”, and “swing arm reward”).

The kit bike needs to be open source software, I think.

 

[Mark911]

I've got independent TCs installed on my pack and I'm seeing temps as high as 70C under the right (wrong?) conditions. Obviously, Alta allows higher temps during thermal limiting.

 

[TonyWilliams]

I've got independent TCs installed on my pack and I'm seeing temps as high as 70C under the right (wrong?) conditions. Obviously, Alta allows higher temps during thermal limiting.

That is just nutty. 70C is likely ABOVE the published specifications for the normal operation of either the Panasonic or Sony cells. I know for a fact that Tesla limits the Panasonic cells to 52C. Maybe we should grab one of each cell from @AltaWest to test to temperature failure?

Alta clearly did not intend for these cells to have a long life!!!

 

[schwankl]

Can we have a longevity thread? Their fleet and folks with empathy have data could help the community. please? I think with a 80/20 policy can see 20yr daily use ... lets share some data. pretty please?

 

[Mark911]

That is just nutty. 70C is likely ABOVE the published specifications for the normal operation of either the Panasonic or Sony cells. I know for a fact that Tesla limits the Panasonic cells to 52C. Maybe we should grab one of each cell from @AltaWest to test to temperature failure?

Alta clearly did not intend for these cells to have a long life!!!

Not if pushed into thermal limiting on a regular basis that's for sure. It was a very hot day and the bike was being ridden HARD. My rider mentioned he felt that the overall power was off probably 25-30% during this period, the result of the limiting process.

Depends on what you mean by "failure"? Overpressure/venting, rupture, open/short circuit, TR (heaven forbid), or just a specific amount of capacity loss? I think various NASA experiments on the LLB2 packs showed that anything under 100C was probably "safe" but I don't remember the degradation signature.

 

[schwankl]

ya temp definitely part of the longevity function ... now we know the 2 types of cells used can just use that data on those. no need for a thread - data exists, just need to dig for a few min. sorry.

 

[Mark911]

I doubt the mfg has data on the kind of loading/charging we see. Alta should have incorporated algorithms for predicting capacity loss based on past discharge/charge cycles into the SOC/SOH calculators. Another bit of data that would be nice to have and possibly part of the sold IP.