XB508 AND XB700LI wiring nightmare, barely moving or showing 10kph?

No replies
Joined: 09/19/2010
Points: 35

So I took a trip out of state and had to pick up an xb508 that was having problems going a decent speed. Either way it wouldn't fit in my car so I took it apart and put it in my back seat and ripped it in the process. I figured it was an easy fix, maybe just a hub motor phase wire or fuse, either way he got new batteries for it, and they are worth about as much as I paid. It has a 48v 12AH SLA should be able to power the XB700LI for a least 5 or 10 miles that's all I need it for.

The key from my xb700li works on the xb508, and it even turns it on, that's a scary thought unless you use a kryptonite new york lock or something haha.

I really don't care if I have to scrap one or the other for parts on the other, I just want a working bike. I was interested in what the xb508 had to offer because some people bring the SLA XBs up to 30 or 35 MPH with a simple shunt and or overvolt mod. I'm sure the xb700li motor can only work better than the 500w one with those mods.

My Lipo4 battery from my XB700li does not have the longevity they promised out of the factory. It has gone from having 15 miles of range down to less than one mile. Some of the cells will not hold a charge. After a few weeks, even though I left it on the charger for over 24 hours to balance it, it still is only 52.6v. It should read around 58v I think, but I saw through the balancing leads that some of the cells are around 3.2-3.3 volts and others are 3.4 and 3.5 volts, this was measured before balancing. I haven't got around to measure each cell again but just seeing that the total voltage of the pack is telling me it is partially dead already. I may be able to rewire the cells or just use half of it, I think I may have squished a few of the sides of the cells running it without a shell on it under the seat with rounded screws under it, oops. Either way it would still be a nice backup battery to have along side SLAs even if it was only 10ah instead of 19ah. I would even like to go to 72v wiring it as 24s with a new bms, and just keep the good cells, but I am not sure how easy they are to split apart and stuff like that, I know you can just crimp spade connectors onto them, thats about it.

I would like to just throw the SLA battery on the XB700li and give it 100v capacitors and bigger mosfets but it would also be nice to leave it stock to still accept the lithium battery without over drawing from it.

I tried taking the hub motor from my xb700li and hooking it onto the xb508 frame with an xb508 controller that was configured with the shunt mod laid out on the website that was called bergerweb, he revised his plans for the mod with electric fence wire to introduce some kind of limiter, but I just want to take the power as fast as possible I can out of the lead acid pack, which he said that original mod would do. I have another stock controller for the XB508 that is not modded as a backup.

I do like the frame of the XB508 because it seems a little more light weight and it has shock absorbers that don't squeek. It wouldn't be that crazy of an idea to think I could move the entire electrical system off of the xb700li and put it on the xb508 for the smaller form factor. I may do that later but it just seems like a lot of work right now.

Is there a certain wire on the xb700li that would make it only go 10kph on the gauges? The voltage meter does move down little bit when I start moving. It was much better on a 50 degree day, I tried it on a day when the weather was in its 40s with both the SLA and the Lipo4 battery and they both had the needle going down about half way as if the bike was drawing all the power the battery was giving out, but it wasn't doing any kind of low voltage cutoff that time.

Any ideas on what my problems could be or what parts I should use where to get the best bike would be appreciated. If I don't get this working it would be a huge waste of time and money.

Who's new

  • Scott2Hotty
  • dragoncat711
  • VITO
  • tomsqr94
  • Iron Mike Golf

Customize This