gwhy

The main problem within the e-bike community nearly all e-bikes are run on 48v upto 110v and there is no off the shelf fast charging equipment for lipo at these voltages so people improvise chargers to allow fast charging of there packs so the risk of something going wrong is much greater than if using a charger designed for lipo. Most Lipo chargers will count the total cell voltages and compare it to what the charger is set to and if they dont match the charger will warn you, and this in it self is a very good safety net. I always check my batterys with a battery medic before I connect the battery to any of my bikes or my charger, this will give a readout of each cell voltage of the pack and this give me a very good indication of the condition of the battery and weather the pack needs balancing. A short in the wiring on the bike can cause a fire ( but this can be with any type battery , not just lipo ) or if a cell gets punchered or damaged . If a cell is much lower in voltage than the rest of the pack (cells ) when in use this will generate heat from the low voltage cell and can also become a problem ( maybe not so much of a problem on the oset's as they are only drawing around 40A max ) my bikes can draw around 100A+ . if you were able to get the wheel to spin at max by shorting ( +5v to the throttle input of the controller ) then this would indicate that it is the throttle at fault. What are the colors of the wires from the throttle and the colors of the wires going into the controller ?. 95% of all the throttles I have played with are red,black, and green but this do not always match up with the color of the wires going into the controller. If there is red and black then these will always be +5v and 0v the green wire is the signal wire. This box for throttle response was talked about in this thread http://www.trialscen...hrottle-on-36v/ ( I may have come up with a really easy fix for this but I need to get out and test it ).

I am aware of 5 battery fires thoughout the e-bike community that Im in touch with in the last 3 years and one of these was a lifepo4 not lipo ( this is a very small percentage of fires) , 2 of the fires were whilst riding and the other 3 were whilst charging. I have no real information as to what happened or how sound the wiring was on these bikes but I do know the 3 fires from charging were all being bulked charged at high rates i.e 10A + and all 3 had a BMS fitted ( this is why I would never have a BMS on my battery's ), one of the 2 fires whilst riding also had a bms fitted and the other was using secondhand lipos ( he didnt know the history of the batterys ). nobody was hurt and no buildings were damaged but all 5 bikes were writeoff's as the batterys were being charged on the bikes. Some way of monitoring the lvc of lipo's is a must as a cell that is discharged beyond its safe limit is a major factor of becoming a fire risk when charging. Edit: This is not osets e-bikes by the way....!!!

if you leave 20% capacity in your discharged battery this can add a extra 50% to the life span and the same with charging them, if you only charge them upto 95% of there full charge this can also add a additional 20% to the life span. I dont nessasary agree with the chart that was last posted, its ok as a guide but the values very much depend on the make and age of the cells, all my packs ( I have 2 of 3 different makes of 6s batterys and are at 50% capacity when the voltage is 23.2v )

I am trying to think of a way of adapting my handlebar voltage display for the osets, it is robust enough for a trial environment but the problem I have is that so many people are using different voltages so they would need to be adjustable to take into account for this whereas at the moment my monitor is setup for 12s ( 48v ).

Hi Spark, If you are revering to the rear foot brake then I have just a standard sherco ( not a moddified oset ) e-brake levers with built in on/off switches are like these ones

They behave just like normal batterys but more care is needed to look after them, if a cell is run down below the safe limit then this can damage the cell and you can risk ( at the very worst) having a lipo fire when you come to re-charge them. there are 2 main rules for lipo , never over discharge them and never over charge them. Special chargers are needed for lipo that take care of the over charging problem and you can get cell monitor alarms that warns if they cells are becoming to discharged in use or you can get a total BMS ( battery management system ) that will shut the battery down if any of the cells are getting to low or if to much current is drawn for the battery. The initial cost converting to lipo is expensive but well worth it. If a total newcomer wanted to start using lipo I would highly recommend never charge the battery on the bike and also charge the batterys in a safe place i.e i in a fireproof box and defiantly not in the house but this should also apply to any high density battery ( SLA is not a high density battery ).

I have been thinking about having the rear brake lever linked into the throttle , but instead of just a switch on the lever it will be continually adjustable dependant on position so it will behave like a clutch, it would work but I will have to try it to see if it is worth while.The main problem would be sorting out a brake lever that will act in the same way as a throttle. You can get e-brake levers and these already have a on/off switch built in and are widely available it would be very easy to setup but like you say a foot brake would have to be sorted out on the osets, but for my application I already have a rear foot brake so it will be just a matter of figuring out the handlebar lever.

there isnt a 'one fix all' solution to this problem , when I first started to play around with throttle control/resolution I fitted a toggle switch that allowed 2 resolution settings. In one position the throttle resolution is halved and this allowed very good slow control but this would mean that the switch needed to be switched to allow full speed ( normal resolution ) this was not to bad once you got used to it, it was like the equivalent of having a 2 speed gear box but without a clutch, it got very intresting if you forgot to shut the throttle off before you switched into normal resolution

The hk alarms are ok but connecting and disconnecting them over time to the balance tap plugs I think potentially can cause problems ( unless the balance plugs are re-enforced some how ) , I agree that if a your disciplined enough to check the voltage every now and again this is normally good enough but theres nothing like having a fuel gauge that is on all the time and can be seen all the time .

Re lipo monitor: I have been using a home made lipo monitor for about 6months now, and was just wondering if I were to make a bunch of them would anyone be interested if I was to start selling them ?. I dont know exactly what the final cost would be but I expect it to be around

The whole electric bike laws are a mine field. a E-cycle with working peddals can be riden on the roads or wherever a normal cycle can be ridden as long as the power of the motor is not over 250W and the top speed ( electric only ) do not exceed 15mph the rider must also be 14 years of age or over, any electric bike without peddles will be classed as a motor cycle and the same laws apply as to gas bikes ( no matter how slow or small they are even the little toy 12v sit on elecy bikes from toys r us) and this also applies to the little elecy toy cars. I have spoken to a local Councillor about the use of e-bikes at bmx tracks, skate board parks and urban parks and he said that he could not foresee any problems getting permission to legally ride these smaller ( slower ) e-bikes at these places. Edit: Having said that I have never had a problem riding my offroad E-bikes up the local park or up the local woods and people are generally interested about the tech and want to know more about it rather than running off to phone the police.

I have tried something Similar ( a Simple RC filter as I posted on the previous page ) and found the shut off delay to be a problem.

Every now and again the clarks come up on ebay new for

Hi Trix, Yes that will be fine.

Yes that will do for your fuse holder.

Nice one

with it like that do you get 24v on the 2 thin wires at the relay? . yes it should work like that, my guess is that the thin black wire ( coming out of the controller ? ) is not connected to the black wire from the battery for what ever reason. if you cut the black thin wire ( that goes to the relay and connect this thin black wire from the relay to the black - on the battery this should switch the relay on ( the throttle lights should come on )

Hi Trix, Can you post up a pic of the relay wired into the bike ? so I can see all the connections. Do you have 2 thin wires on the relay ?. Both the relays will do the job. edit:

The relay needs to handle at least 40A so a switch will also need to handle around 40A +, the trouble with high current switches they tend to be very large and expensive, a better bet would be to buy a nice set of high current connectors ( plug and socket ) something like anderson power poles (75A) that you just plug in to each other to arm the bike, and not have a switch at all. The trouble with this is there will not be a quick easy way to turn the bike off should something go wrong.

with your voltmeter set to dc volts connect the red and black meter leads to the small red and black wires where they connect to the relay, when the keyswitch is on you should read 25v at the relay, if you get no reading then leave the black wire connected and trace the thin red wire back to the keyswitch and put the meter red lead on the keyswitch , with the keyswitch on you should get 25v. if you get 25v at the relay then remove the red meter lead and connect it to the other thick red wire where it connects to the relay you should read 25v which should power the controller. edit: Just looking at your pictures again and it dont look like if you have a black wire going to the relay, you should have 2 thin wires at the relay that will read 25v when the keyswitch is on.

Hi Trix, you can test the motor by taking your red and black wires from your battery and connect them directly to the red and black ( I think they are Red and black but it really dosnt matter, if you connect them up the wrong way round the motor will go in verse )wires going into the motor, make sure that the wheel is off the ground and the bike is held stable and fingers out of the way of every thing that moves when you do this as the motor will instantly go max speed ( if it is working ) . You can bypass the keyswitch, relay and fuse wireing just by connecting the red and black from the battery directly to the red and black that goes into the controller, this should light the throttle light if you still do not get any throttle light then check the connections to throttle.

If you have +5v on the throttle connectors and 25v going into the controller then I cant see how it is the battery's

It really do become a problem when you have a bike with even more power and top speed, yes kids adapt, but the more tricky the sections become that lack of really fine slow control become a issue.

This is exactly the problem ( their isn't enough throttle resolution ). It can be got used to but when the throttle starts to get old or its not as free moving as it should be that first 1/16th or so of a twist becomes physically jerky and much harder to roll on smoothly. Its that maximum torque from 0 rpm of electric power, unlike a gas bike.