I want to go faster.

Moderators: robnewyork, bassiclyLouDog, gameboy

well when i first tested 86.9v worked like a charm just over 54kph. but like i said i charged over night and must have got me just over what the controller could handle. i had been running 72v but was still too slow for my commute.

i build electronics and likely have any parts that it may need. so hoping i can swap the 60v caps in the controllor will some 100v or so and get it working again.
it is just the cap that is blown from the looks of it. hole blown through the bottom. 63v 1000uf. dont think i have one that big or bigger kickin around but if i find one im gunna try it. and other than thottle not working everything else still does.

well looks like this one is going to have to go back. rode to town yesterday, my boss took it for a cruise around the block and the thing crapped out on him. though the battery died, but after charging motor just humms
ok so after looking over the data sheet again i don't think this will handle 48v. im guessing it's rated at 50v i can see it ends with the '0' and not a '3' so not likely a 63v cap or a 10v so fully charged my batteries would be more than 50v correct.. so there is a chance it can handle the couple extra volts as my scooter cap rated at 63v didn't blow till i gave it 84+ volts..

pulled it right apart today was going to change the cap, but it looks like i blew 4 fet's as well so gunna need a few more parts. contacted a place for a controller 84V. think that should make scooter plenty of fun..
What risks if any are there doing shunt mod? and the contoller in my new bike has over current protection 15A so i was wondering if the shunt mod would even work. What do you think?

Also when accelerating it takes alittle kinda speeds up slowly. i remember a while back a guy talking about how to remove this so you turn the throttle and go..
since that controlers are like £30 its easyer just to get a bigger one

If your considering a shunt mod its quite hard but if you can solder and do the math
and not worried about killing your controler go for it.
If you ask for more than a extra 15% more power your likely to burn things
not worth the effort personaly.
(but i can guide u how to do it properly if you choose to)
Ive done a shunt mod in my scooter. but this mountain bike says that it has ocer current protection. so really im wondering if shunt mod will still work on these controllers with this feature. i wouls be interested in what math is used to calculate proper shunt mod. i just built up some solder on the shunt not following any equation..
It does but its impractical to use in the real world
shunts are like 1-2 ohms.
If you want to messure there value you need a very accurate volt meter and mesure the voltage drop over the shunt
then work it out from there but like most things there is a easyer way.

Lets say that its a 30A controler and the shunt is 10mm long
if we harlf its lenth we add 50% more power (45amp total) but thats unsafe.
So lets say we make it 2.5mm shorter (total lenth of 7.5mm)
this would give a increase of 7.5 amp (37.5 amp total)
which is about as much as you can ask for without causing too meny problems

to shorten the shunt there is only 2 real option
1st cut it shorter if its possible
2nd use a single thread of thin copper wire and wrap it round one end of the shunt untill you cover the requied lenth
then solder over the top of it with a very hot iron wetting it to the shunt
shunt mod.jpg
shunt mod.jpg (10.18 KiB) Viewed 4708 times
Ok so just as well off to mod this bike and keep the hub motor. my plan was to get a 24v hub and use current controller and battery. but if at all posible i would like to do more than 40kph. 50 -60 is goal. once i get the new controller for my scooter i wont be riding the mountain bike as much so will have time to make some changes for speed.

It was finally time to hook everything up and turn[…]