The battery keeps dying after 2 mins when i put full bean on, when riding it will cut out when changing down or when stopping.
How to fix it?

well im guessing reg/rec, but the first test is start your bike with the lights on, rev it and note if the lights get slightly brighter when you do, if they do your alternator is ok, and if thats the case it leaves only two possibilities im aware of, dud battery or dead reg/rec, or possibly both

usually when the reg/reg dies, it takes the battery with it! as rec/rec no longer does its job, it lets too much charge get to the battery.
if you fit a new battery, it will only get killed.
swap the rec/rec 1st, battery 2nd.

Just tried the lights when reving and no change in brightness so i think its the alternator, plus its got a new battery on it.
How much are they, second hand or brand new and fitted?

Ok where to start…

It sounds like a reg/ rec fault but it may not be so its process of elimination time. Firstly what’s your mechanical knowledge level and how competent with the spanners are you? Secondly have you modified the bike if so what have you done to it?

Now with those answers its time to get the multimeter out. What voltage does the battery show with the ignition off? With the engine running at idle? With the engine running at 5,500 rpm? With the lights on at 5,500 rpm? What you want is a good charge going thought to the battery at the 5,500 rpm mark as this is where the engine starts to charge the battery. You want to see between 13 – 14 volts IIRC as I don’t have a bible in front of me to check. Anything more or less indicates a problem. After these results we can give you a few more tests to identify where exactly the fault is.

Also where abouts are you as there might be a forum member close by who is willing to help if need be.

http://www.electrosport.com/technical-r ... -guide.php

the above link has a electrical fault finding chart. see if it helps...
SQ has also got good advice.

get the battery charged fully......then start the bike and test the voltage output!!!!!!!
as was stated before it should read between say 13-15 volts at 5000rpm..

if its not charging at all the voltage should drop below what the fully charged battery was reading and if this happens its almost certainly the reg/rec which has packed up.......

if it does what happened to me where it was getting a charge,but only a slight charge because the stator windings(alternator)was on its way out then the charge rate might be between 12.5-13 volts but what happens is when you use your lights the battery drains faster than its getting charged.....

the same happened with me where the alternator was charging the bike slighly but when you slow down at a junction the alternator isnt producing as much power so the bike cuts out.................

i recommend doing the charge rate check first....... :D :D

hi ive found that its the reg reg its broken and fried its self. wheres the best place to get 1 second hand or brand new on the internet? ebays are 50 buff

wullvfr wrote:get the battery charged fully......then start the bike and test the voltage output!!!!!!!
as was stated before it should read between say 13-15 volts at 5000rpm..

if it does what happened to me where it was getting a charge,but only a slight charge because the stator windings(alternator)was on its way out then the charge rate might be between 12.5-13 volts but what happens is when you use your lights the battery drains faster than its getting charged.....

bro, my bike charging rate around 12.5-13.1V...is that an indication where i need to replace my alternator? how much time left?

if you think £50 is expensive....
wemoto are charging £70 with no P&P

email GF for a quote.