Future on the past, e bike

E watt ?

Retro Newbie
Hi Retro bike and its peoples,
I Buy 80s 90s MTB to strip, restore or turn into e bikes, but I'm having issues with this one (please see pics), LCD display shows full battery, if used for a few seconds battery shows empty but still works, battery checked, voltage good, works fine on the stand, but when riding if throttle is twisted it cuts out after a second, if re-twisted it does the same, if twisted slowly and the wattage is kept down it works, lights on battery indicate full charge, if anyone has some advice, ideas, answers i would be most grateful, if there is a relevant site someone could point me in the directions off this would be helpful too, cheers. E watt ?
 

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Something is either stopping the current flowing or more likely the battery is bad and cannot supply the current which makes the volts drop.
 
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Hi mdvineng, thank you for your reply, this is what i thought, but i checked the battery under load and voltage didn't drop, im fitting out a Saracen Limited Edition at the moment so i might just order another battery to check it as im going to need it anyway, thx again. E watt ?
 
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I'm by no means an expert on the subject, but has that rear wheel been put together correctly? The spoke pattern just doesn't look right to me and the angles some of them leaving the rim looks off.
 
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If the battery is good, maybe it's the controller. It's probably the most complicated component, so perhaps the most likely source of the fault.
 
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Hi again all, thank you Rank_21 for the site :), looks like what i have been looking for.
Mdvineng i dont think its a short but i have had issues with broken wires before, some of the wires are so thin, it took me time to find the broken wire last time, i hooked up the battery to another controller & lcd and there seems to be issues again but i cant test it underload at the moment, so I'm going to order another battery tonight.
Hi billy, the bike isn't finished yet, but saying that the wheel will only receive a light tune so it wont look much different.
Welcome to the world of fitting new to old :)
I learnt to build wheels a long time ago and I have laced many wheels from radial to cross 4, funky to normal but i am know expert, I'm learning all the time, sometimes by making mistakes.
The pattern is caused by the size of the hub, the bending of the spokes is because it is cross 3 on a larger hub, so the angle of the spokes is more acute then that of a wheel with a smaller hub, this also causes issues with the rim, as the nipple doesn't have the correct angle in the rim, i can get round this by drilling the nipple holes in the rim at a slight angle or making the holes larger, this is tricky, the other way is to do a cross 2, the spokes would be shorter and the angle would be less so this would solve the problem........but a cross 2 is weaker then a cross 3, and as it was a cross 3 to start with and I am adding 250 to 350 watts on top of the persons pedal power, this is not recommended in my opinion (this is why I also fit a torque bar to the rear wheel) I can solve this by using larger gauge spokes, but then it would notice and I am a anal freak that like things to match and look as original as possible (this is why i also try to hide the pedal assist wires and sensor and the brake wires and sensors) plus i could still need to make the rim holes bigger to accommodate the larger nipples.
As it is i am limited to 36 hole wheels, as the hub motors are 36 hole and old rim very a lot, some have the holes drilled at an angle, some are drilled straight, some are offset, some are not, old mavic rims can be riveted round the hole, and there is double & single walled rims, plus i only use the best condition 80s 90s mtb bikes i can find, so you see it is a tad tricky :).

It may not look ideal but it is safe and i think it is the best solution to the problem, but what do you think ? and what do other ppl think?, is this right ?, is there another way?.

Here is a couple pics, the other wheel is of my 1000 watt ebike, its is a brought wheel with a large hub, cross 1 with heavy gauge spokes but still has the pattern.

Another problem i have is the weight of the battery on the mounts ?, I'm using water bottle mounts at the moment, but what is the strength of the mounts?, again so many types, reverted, glued, wielded, brazed....this is why i use cable ties for added redundancy, i dont want to as it looks poo, what do people think ?

Thank you all again for your input. E watt ?

ps sorry for spelling & grammar mistakes.
 

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Thank you xerxes u maybe right, and often all wires are different colours from controller to controller and different connectors as well lol, after i try a new battery i will order a new controller as the ones i have have all different connectors and wires, thanks you again for you input.
 

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