so if on flat you pedal slowly on top gear and maximum power you risk falling asleep due to so little effort, ha ha!
Panasonic System Power Delivery Explanation
- Thread starter flecc
- Start date
Actually not far from the truth. Less than 100 watts are needed to propel the bike at moderate speed on the flat in still air, and in high power mode the bike would provide 57%, The balance of less than 43 watts is similar to the 50 watts our bodies use while seated on a chair.
.
Not at all cogs, basically because it doesn't use a standard bike frame since the unit completely replaces the bottom bracket and all lower tube end parts.
The frames on the bikes using these have a curved metal channel joining to the down tube, seat tube and rear frame tubes, the motor unit bolting into the metal channel at three points.
In addition the battery is integral so has to have the appropriate space behind the seat tube, not available on normal bike frames.
.
The frames on the bikes using these have a curved metal channel joining to the down tube, seat tube and rear frame tubes, the motor unit bolting into the metal channel at three points.
In addition the battery is integral so has to have the appropriate space behind the seat tube, not available on normal bike frames.
.
Cheers flecc.
It is becoming increasingly clear that what is required for the perfect electric bike are frame tubes that incorporate battery's within their structure, the battery's to have an indefinite life span, and which also have the quality of malleability that enables pleasing design.
i'll knock some up in the sheddy tomorrow..
It is becoming increasingly clear that what is required for the perfect electric bike are frame tubes that incorporate battery's within their structure, the battery's to have an indefinite life span, and which also have the quality of malleability that enables pleasing design.
i'll knock some up in the sheddy tomorrow..
Flecc
Very interesting article. I`m just learning how best to ride my bike and you have just answered why I can chump along quite nicely in top gear. On the flat the balance seems fine and I can use the slightly higher gear than I would normally choose on a standard bike. Going down hill is when I usually rest (so no change there then) but going up hill I tend to be able to stay in that high gear(although the bike slows down somewhat) the input seems to be the same as on the flat.
Now I suppose fitting some sort of computer to measure the wheel speed might well be the ultimate answer but in reality I find riding the bike pretty much a joy as it is.
Very interesting article. I`m just learning how best to ride my bike and you have just answered why I can chump along quite nicely in top gear. On the flat the balance seems fine and I can use the slightly higher gear than I would normally choose on a standard bike. Going down hill is when I usually rest (so no change there then) but going up hill I tend to be able to stay in that high gear(although the bike slows down somewhat) the input seems to be the same as on the flat.
Now I suppose fitting some sort of computer to measure the wheel speed might well be the ultimate answer but in reality I find riding the bike pretty much a joy as it is.
Yes it is an unusual system but as you say, once used to the way it works it's fine for most. Regular cyclists who prefer high cadences (pedalling speeds) are not always so happy though, and once in a while there's the odd person who positively hates it. They usually prefer something like the Cytronex, virtually an ordinary very light bike with some optional power available for hills and headwinds.
.
.
Hi flecc,
I`ve got a problem with my Panasonic motor (Giant Revive E N3).
I was driving to town without problems,but after a pause of 2hrs the motor wont start.As usual,I startet the controller with "Power on" and the LED are lighted normally.But when starting pedalling,the motor stands still,controller shows all LED lightet (normal reaction).
Sometimes when the controller has problems,it beeps and LED blinks.Then I restart the controller and everythings allright.
But now the controler shows OK,but the motor dosn`t start.
I thougt about a problem with water,but after 2 weeks in a dry garage the problem still persists.
What can I do?
greetings,
pedelecPit
I`ve got a problem with my Panasonic motor (Giant Revive E N3).
I was driving to town without problems,but after a pause of 2hrs the motor wont start.As usual,I startet the controller with "Power on" and the LED are lighted normally.But when starting pedalling,the motor stands still,controller shows all LED lightet (normal reaction).
Sometimes when the controller has problems,it beeps and LED blinks.Then I restart the controller and everythings allright.
But now the controler shows OK,but the motor dosn`t start.
I thougt about a problem with water,but after 2 weeks in a dry garage the problem still persists.
What can I do?
greetings,
pedelecPit
Your Giant Revive Spirit uses a variation on the Panasonic unit which I've never worked on, different in a few ways, and it may be the control unit is causing this problem. It's impossible to be certain though with that variable behaviour, so I think the best bet would be to consult one of Giant's e-bike dealers. Repairs are only done by exchanging units, either control unit or motor unit, they aren't repaired, but Giant sometimes send out diagnostic equipment to help a dealer assess a problem. Here's the link to Giant's UK dealer page, when you enter your town or postcode, select the Hybrid box below, these are the e-bike dealers:
Giant Bicycle Dealer Page
.
Giant Bicycle Dealer Page
.
Last edited:
Lafree system
High Flecc,
really interesting thread. Does all of this apply to my Giant Lafree as well, ie the assistance being 1 - ( [kph - 15] / 9 )? Do you know of any modifications I can make to give a 1.3 boost to the Lafree in a similar way to the new Panasonic system?
How much does overvolting change things? There is clearly a difference when the battery is fully charged to one only at 25%. How much can you safely overvolt the Panasonic systems?
High Flecc,
really interesting thread. Does all of this apply to my Giant Lafree as well, ie the assistance being 1 - ( [kph - 15] / 9 )? Do you know of any modifications I can make to give a 1.3 boost to the Lafree in a similar way to the new Panasonic system?
How much does overvolting change things? There is clearly a difference when the battery is fully charged to one only at 25%. How much can you safely overvolt the Panasonic systems?
Hi Tangent. Yes, this does apply to the first Panasonic unit on the Lafree, but it's circuitry is differently executed and there is no way of introducing a higher power level. Even if there was, it might not be advisable since the main circuit board was one of it's vulnerabilities, causing a few failures, hence Panasonic's redesign.
It should be possible to use a lithium battery with 26 volts instead of the standard 24 volts, but no-one has tried it yet though I couldn't see it causing trouble. I certainly wouldn't recommend using higher voltages than that though.
Depending on which gear hub you have, one way to get just a little more power if you don't have hills that make you use the lowest gears is to reduce the size of the rear sprocket since that would lift the power phase down point slightly. This would only apply on the SRAM 5 or 7 speed gears though, and the gain would be very small.
.
It should be possible to use a lithium battery with 26 volts instead of the standard 24 volts, but no-one has tried it yet though I couldn't see it causing trouble. I certainly wouldn't recommend using higher voltages than that though.
Depending on which gear hub you have, one way to get just a little more power if you don't have hills that make you use the lowest gears is to reduce the size of the rear sprocket since that would lift the power phase down point slightly. This would only apply on the SRAM 5 or 7 speed gears though, and the gain would be very small.
.
Thanks Flecc, will definitely not try overvolting then! I have already done the gear ratio trick by installing a Shimano 8 hub an 16T sprocket. This made for a much better bike and improved the speed a bit. Still considering battery options. I am down to either
1) Ping 10Ah LiFePO4 external
2) 4.6Ah sub-C, internal battery upgrade
3) 2 times 4.6Ah sub-C packs in parallel, internal
4) A proper 9Ah D internal replacement
Still not sure whether I can put sub-C packs in parallel without messing about with diodes. If so this would be a very cost effective option.
The Ping battery looks great, only disadvantage is that it would not fit in the existing battery case.
I am making progress on getting a D replacement at a reasonable price (£130-£150).
1) Ping 10Ah LiFePO4 external
2) 4.6Ah sub-C, internal battery upgrade
3) 2 times 4.6Ah sub-C packs in parallel, internal
4) A proper 9Ah D internal replacement
Still not sure whether I can put sub-C packs in parallel without messing about with diodes. If so this would be a very cost effective option.
The Ping battery looks great, only disadvantage is that it would not fit in the existing battery case.
I am making progress on getting a D replacement at a reasonable price (£130-£150).
The D replacement would be the best option if the cell discharge rate is adequate, otherwise option 3 with the parallel sets of sub C packs. I don't favour a single sub C pack since the discharge rate would restrict the performance.
With the parallel setup, it would be best to use Schottky diodes in the outputs to prevent cross charging, thogh there's a small performance loss from that. Alternatively, Tiberius (Nick) in this forum has produced some "ideal diodes", tiny circuits which give no loss separation. If you PM him he will let you have the details and price, but you'd need the dimensions to see if they'd fit in the pack with those 4 sub C packs.
.
With the parallel setup, it would be best to use Schottky diodes in the outputs to prevent cross charging, thogh there's a small performance loss from that. Alternatively, Tiberius (Nick) in this forum has produced some "ideal diodes", tiny circuits which give no loss separation. If you PM him he will let you have the details and price, but you'd need the dimensions to see if they'd fit in the pack with those 4 sub C packs.
.
Ping can make customised packs, there may be an outside chance of getting one to fit...just a thought...
Surely that would only be an issue with cells of differing chemistries or capacities. Integrating diodes within the pack itself for NiMH would mean that you'd be unable to charge the pack, unless you added a second set of connections to each of the cell clusters.
For battery packs which have a BMS, differing chemistries, or capacities then protection diodes are essential to prevent reverse-charging, but if all your cells are the same chemistry and same capacity, then the norm is just to hook them up in parallel - You actually want all the cells to charge/discharge at the same time anyway.
Hi Fecn/Flecc,
Only one real way to find out. I will try out sub-C packs in parallel, bench tested before I stick it all inside my battery case. To avoid any minor explosions or fires though I will put a couple of in-line fuses in series with each pack. I guess 20A should be about right.
In particular I am interested in determining:
1) Whether there are any problems using similar packs in parallel
2) The benefit, in terms of usable energy, obtained by using packs in parallel instead of running one down then switching over.
3) A comparison with my clapped out batteries
4) A comparison with a new 9Ah D cell based battery, if I can get hold of one.
I will test over a range of discharge rates and will post the results as I get them.
Only one real way to find out. I will try out sub-C packs in parallel, bench tested before I stick it all inside my battery case. To avoid any minor explosions or fires though I will put a couple of in-line fuses in series with each pack. I guess 20A should be about right.
In particular I am interested in determining:
1) Whether there are any problems using similar packs in parallel
2) The benefit, in terms of usable energy, obtained by using packs in parallel instead of running one down then switching over.
3) A comparison with my clapped out batteries
4) A comparison with a new 9Ah D cell based battery, if I can get hold of one.
I will test over a range of discharge rates and will post the results as I get them.