gwhy

So how much would you consider a fair price ? ( but for something that rides like a 250 )

Hub motors have been around for over 100years they are very very heavy for what they are ( very old tec ), and do not produce much torque unless its a geared hub but then the gears are normally the weak link in a hub motor, you would be maybe looking at around 10kg of weight in the wheel( cooling is also a problem with high power hub motors), you will also be limited to change the gearing on a hub motor as its all built in, Bicycles are able to get away with it due to the weight, the only real contender hub bike out there is the 'bomber' its a very good mountain bike but would not cut it for any serious off road stuff ( very good for trails but not trials ). I have ridden a high power hub motor setup on a push bike and it just dont feel right because of the big weight that far out from the COG

I have heard through the grapevine that the kit will be around 5k euros but this do not include the donor bike. I may be well off ( I hope I am to be honest) a more realistic price for a kit would be around 2.5k euro's. Edit: out of interest what would people consider a good price for a bolt on kit for existing gas bikes.

The motor in the back wheel would not be any good for loads of reasons ( its ok for riding on the streets but no good for anything off road. A clutch is also not needed but could be mimined using the controller if people really feel the need to have one ( I dis-agree about a elecy motor not having the puch or torque than a gas bike with a clutch ) as long as the motor/controller can cope with it. hear is another vide from the trials camp of lecy bikes ( this is the sort of vid that gasgas should have put together for there promo vid )

Looks like KTM is getting in on it as well:

The 2012 zero E-motorcycle has now been released . I think this vid speaks for itself as reagrds what a electric off roader can do, now lets see this package on a trials bike , there new range of road bikes also looks very interesting and claiming a range of over 100 miles per charge at 80mph

true but when the bikes weight comes down to around 35kg (which is possible )it will be a bit obvious.

Another battery pack would make it about 68kg ( legal ) and will double the range but the whole battery pack would have to custom made and re-designed to fit in the frame better. price would be expensive but it depends on what battery chemistry they are using. The clutch is not really needed with a electric motor driven bike and it will be difficult to get used to as it will be so different but it really depends on how the controller is setup on the bike to how it rides.

just something quick to think about ... electric motors can have the powerband of a 2 stroker but through out the throttle range...from 1 rpm to max rpm (Unlike a gas bike) so in real terms electric trial bikes can be very competitive. Im not saying that the GG will be as competitive as the next bike to be released ( but give me a 10kw electric motor over a ICE 250cc anyday for torque and control as long as the bike is designed right )

I was just reading in another thread about there is a minimum weight limit on trials bikes of 65kg do this apply with the ACU reg's ?, I didn't know there was such a rule and if there is, where do that put this GG weighing in at 61kg .

I dont want to start cluttering up this thread, but if you really want to know more about my bikes then drop me a PM and I will give you all the details.

Nope you will still need a motorcycle licence and insurance ,, but no road tax and it will need peddles the price i have seen some where for the kit i.e motor, controller and battery is 5k euro's, the spec that I have seen for it is that the motor produces 10kw peak power (13hp)

I would recommend 2 of these they are what I use and have been very reliable ( I have 4 of them ) http://www.hobbyking.com/hobbyking/store/__7028__Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_accessories.html with the config that you are going for that way you can treat each bank of 5s as separate battery's and havin 2 chargers will half the charge time. You will also need 2 Mains laptop psu's These can be got from e-bay output voltage anywhere between 12-18v and a min current of 5A something like this http://www.ebay.co.uk/itm/15V-5A-AC-CHARGER-ADAPTER-TOSHIBA-TECRA-M1-M2-M3-M4-/150561700685?pt=UK_Computing_LaptopAccessories_PowerSupplies&hash=item230e2d3b4d#ht_2944wt_1008 Each of these chargers will charge a 5s pack at around 2.7A per hour so a totally discharged 20Ah pack it will take around 8hours to charge but in real life you should never fully discharge a lipo so the actual time will be more like around 6hours The biggest charger that will do the job is this one http://www.hobbyking.com/hobbyking/store/__11340__TURNIGY_MEGA_400W_Lithium_Polymer_Battery_Charger.html This will charge a 20ah 5s battery in around 1 hour but you will need a very meaty mains psu to power it ( 30A 12-15v) you could make a charging harness to parallel both your 5s packs when charging and this will give you the 2 hour charge time that you are after with just the one charger. A good all round piece of kit is a watt meter http://www.hobbyking.com/hobbyking/store/__10080__Turnigy_130A_Watt_Meter_and_Power_Analyzer.html this will give you a form of fuel gauge for your battery it will also record amps and volts and it is really usefull for getting the max performance (tuning a E-Bike ) Betarambo made some very good points, It will be best to start with a basic setup i.e 10Ah battery and 2 smaller chargers ( for simplicity ) until your happy with how the lipos work. maybe even go with 2 10ah battery packs rather than 1 20ah battery, not even thinking about the safety aspect of such a powerful battery but also think of the cost, should you accidently destroy a 20ah battery all in one go.

For maximum life expectancy for lipo's, avoid discharging below 20% capacity, so leave at least 2Ah of charge in the battery if its 10Ah, never totally discharge lipos as this can damage them permanently. A well looked after lipo battery should be good for 200+ recharges before the capacity starts to drop.

It looks like you have a good grip on what needs to be done and are asking all the correct questions. There will be no heat issue with stacking the batts ( if the 15C's battery's get remotely warm on these bikes then there is a serious problem that needs to be sorted ) With a 24v bike it is a little easier just use 6s gives you 22.2v ( 25v hot off the charger ... perfect and easy to charge with 1 charger and one connection) but with the 36v bikes it takes a little more thinking about. Two 5s lipo (in series )will have a voltage hot off the charger of around 40v which is a fair bit higher than the 36 volts needed and two 4s lipo (in series) will be around 32v hot off the charger and thats a little low, If it was me I would go with the 5s battery's and use 2 chargers as the hot off the charger voltage will drop very quickly down to around 38v. 3X 3s will be perfect but at a cost of making the charging a little more complicated also more inter-connections to go wrong. If using 3X 3s the easiest way is to use 3 chargers ( 1 charger for each set of 3s ) these 3s can be as many as you need paralleled up or the same with 5s but with 2 chargers. If you configured the connector into the controller ( i.e 3 connectors for a 3s setup or 2 connectors for a 5s setup ) in such away that this is what connects the the battery's in series when plugged into the bike, when the battery is not plugged into the bike there will be 3 connectors from the battery ( each connector is a 3s battery that can be charged with a standard lipo charger) Charging your built up battery: balancing the whole pack should not need to be done every time you charge the battery, but very important to balance a new pack before use ( Both my 6s2p have around 30 or 40 charge cycles on them and the cells are still balanced ( but I do check about every 5 charges ) If a cell in a pack is going out of balance quickly then its more than likely there is a bad cell in the pack. So what I'm saying is don't worry about the balance taps and having to connect these up every time you recharge your battery ( just check once in a while ). When building a battery pack balance the individual packs before you parallel them, once all the individual battery's are balanced then parallel the balance taps ( so you have one set of balance taps for each bank of 3s ) I hope this all makes sense.

Yes you can charge the battery from a car battery but as Mike have said it will drain the car battery in no time and possible damage it. The PSU's can be bought cheap, you will need for each charger a psu capable of 12-18V at about 5A these can be found new on ebay for around

I just had a look on HK websitelooks like the only 10s bat charger that they do is this one charger you can charge both packs from one charger but will take longer to charge so 2 chargers would be better but that will work out very expensive ( the chargers are expensive ) in addition to the chargers you will also need a 15A mains power supply (to power the chargers ) and that in itself will be expensive. With the cheaper 6s chargers you can charge all cell counts of battery upto 6s cheaper charger this charger will not charge as fast as the 10s one but even if you bought 4 cheaper chargers it still works out cheaper than the expensive one, the mains psu's for the smaller chargers are also cheaper than 1 big one so 4 cheap chargers and 4 5A mains psu's will come to about the same price as just 1 of the exspensive 10s chargers without even buying the mains psu for it. I hope this makes sense, it can be all a bit of a mine field at first. To answer your original question you can charge as many 10s packs all at the same time with one 10s charger at the cost of it takes longer to charge.

You will need a CCV charger for lipo's , I not sure if HK do a upto 12s charger ( if they do it will be very expensive ) you may be better off using 2 18v (5S)or using 4S and a 6S( you can just have 1 charger but it will take twice as long to charge the pack )remember that a 10s lipo will give you around 40v'ish hot off the charger ), buy 2 6S chargers from HK I think they are around

Hi Pete, It would be easiest to use the oset 36v charger as you say and just connect the batterys in series yes that will work.

Providing they are all good battery's then you could just parallel them up and use the existing charger but this will make the charge time longer. There are some very good 10Ah chargers about for SLA batterys if you want to charge them up faster. Do you mean you have a 36v sla charger in the house?

Its vids like this that will make people sit up and realize that for real power Electric is the only way to go. The chap In the vid that made that bike is a power freak and always pushing the limit , The bikes Im playing with has as much power but do not have as much top end, the bike in the vid does around 60mph and my bikes are only geared for 30mph, the power delivery from a very powerful electric bike is a whole new ball game and great fun.

Those lipo's look a bit lost in there , Personally I would still put them in a ali box for safety reasons.

What make of lipo's did you get ?, Lipo do need a settle down period before you start to get that max capacity out of them but less than half stated capacity do seem excessive.