My kick scooter project

[ElectricGod]

I think this will work OK. I'll try something else if it doesn't.

 

[Ianhill]

I don't think it be an issue the way its fitted nw, it should keep it all lined up nice nw just on top will create drag use more power.

Think of it like if your on top its your energy u wasting on the bottom is more efficient and smoother pun intended

 

[ElectricGod]

I checked my chain tension when I got into work this morning. It was exactly like it was when I set it up on Friday. Yeah!!! Also, I had no skipping or chain derailing like was randomly happening with the drive side tensioning. I'll give it a few more days and then replace those wood parts with something better that hold the chain tension. My teak wheel suffered no discernible wear at all. On the drive side I could see wood dust on everything as the chain bit into the wood roller and wore it out. There was nothing this morning. I have purchased a new rubber roller because it's quieter than the wood roller. I'll have that in a week or so. The rollers come with really low grade bearings. I bought the same sized bearing in a sealed precision version. I'm running a set of them in the wood roller. I'll do the same in the rubber roller.

 

[Ianhill]

I learnt it the hardway too, on a push bike I had years ago before i flopped my leg in half, I guess because I was peddaling the drag was more noticeable and extra effort I was putting in there's more to the old chain than it lets on can improve efficiency loads between good and bad,n I always comment to people on mountain bikes badly setup and maintained don't think they like it but save they legs some work.

 

[ElectricGod]

I don't think I posted this stuff previously or if I did it wasn't all together like this. Anyway, here goes. LOL!

I bought 2 of these 50 amp 20S BMS on ebay. The one on the LIPOs has been in service since I moved to 20S and the LION BMS has been in and out of the scooter a few times, but has seen 2 or 3 months of use. Before that, I balance charged the LION packs every couple of months. They work pretty well and are quite compact at about 3.5"x3.5". One is in the front compartment protecting my LIPO packs and the other is in the back battery box protecting the LION packs. Considering that they cost me a little over $60 each and that they keep the cells all balanced pretty nicely and have status LEDS for each channel, I can't complain about how well they work. I have wrapped them in Kapton tape every way I can except at the balance connectors to protect them from shorts and possible water invasion.

I have 3 LIPO packs in the front battery bay. They are nearing end of life as they are only delivering about 4000mah each and were originally 8000mah. I'll eventually replace them with laptop cells. The LION cells are doing most of the work now anyway. I took the balance wires and soldered 3 sets of 5S balance cables to them. That allows me to monitor all 3 LIPO packs via a single BMS. It's a bit of a spagetti wire mess as a result, but works reliably. I have read several postings on R/C sites and elsewhere about parallel balance charging LIPO packs and that it works quite well. The BMS is in there under those wires and it has performed quite well in keeping all 3 packs balanced. You will notice that connectors are labeled 1 to 4. It's is UBER important that the balance cables go on the correct balance connector on each battery pack. If you connect one to the wrong place, things go badly for the balance connectors. Those tiny pins in there are good for maybe 1 amp so they melt down instantly if something is plugged in wrong.

This is the back battery box. I have one of those 50A 20S BMS monitoring everything back here too. It's more wires running around in the box, but it's the exact same idea as the LIPO setup, but with three more packs. I had a couple of cells in here go south on me so I had disconnected everything so I could find which were the bad cells. Anyway, I took this picture and the above one because I had just reconnected the BMS to these packs tonight. There is a couple of disadvantages to parallel balance charging multiple cells, but anytime you have cells in parallel you have this problem. And that is the good cells mask the bad cells to some extent and a really bad cell will drain down the good cells since the bad cells may be partly shorted internally. With all those connectors on each pack, I can disconnect a pack from the whole and find the weak/bad cells. If these batteries were all welded together, that would be impossible. The BMS is in the front of the box under all that wire mess. I considered zip tieing it all up or just shortening the wires to make it all as neat as possible, but I don't really care and all of it is covered up anyway.

 

[ElectricGod]

I took off the teak parts and made this aluminum piece. It's elongated slots allow me to loosen or tighten the chain a little. I used a couple of stainless steel knobs for a dresser as my retainer nuts. I can crank on them pretty hard to hold the slider plate tight. The holes through the frame were already there from when I had mounted the tensioner some time ago for the old 2000 watt motor. They were conveniently located for the slider plate.

 

[Ianhill]

Looking snazzy awesome job know fairplay got there in the end.

 

[ElectricGod]

The weekend was busy and I never got to test out the tensioner plate until my ride into work today. Anyway, With the old pieces of wood, there was a little chain slack that developed after a 5 mile ride. That's not there at all. I just checked it and my chain is exactly like it was when I set it up on Saturday. A few more days will prove it out.

 

[ElectricGod]

On the way home the 12 volt electrical system stopped working. So all my lights and the horn were dead. I rode home without lights. I pulled out the DC-DC converter and it appears to be fine. I don't know why it all stopped working. Anyway, I put it all back together and found the motor wasn't working. GRRR! just what I needed, another problem that wasn't there when I got home.

 

[ElectricGod]

Well I figured out the problem...but it's a royal pain to fix. The hall cable wore through on a rough edge on the frame and created a short in the hall cable. Then there's a hidden problem I didn't know about. There's something that is putting the battery voltage onto the scooter frame. I can put my DMM on the negative side of the power buss and then touch anything unpainted on the frame and measure the battery voltage. This is NOT good!!!. Damn! What a shock hazard! So anyway, via the short in the hall cable, battery voltage was applied to the motor halls and they got fried. Hopefully the motor controller is undamaged. So the royal pain is finding the +batt to frame short and replacing the halls in the motor. Well my work is cut out for me!

 

[Ianhill]

Devastating u not had much luck with this lately,Just don't know what to say that alot of bad lucks all in one, im pray for the controller halls with you.

 

[ElectricGod]

and the problems still continue...

I found the sneak short and took care of that last night so at least the frame isn't charged with 82 volts anymore. I still need to take apart the motor which is a lot of work to get out of the scooter. Since I was in the battery bay looking for that short, I found this too. The front end is welded to a flat plate on the front of the battery box. The 3000 watt motor pulls pretty hard so I hang on. The leverage on the handle bars has been stressing the mount points for the front end. I'll have to take apart the entire front end and unwire everything up front to fix this. UGG! It will require welding some kind of stiffener on there. Since I will be taking apart the front end, I might as well eliminate the folding mechanism that doesn't ever get used and just creates slop in the system anyway. I'll probably cut off the existing plate and weld on a thicker one and then weld the front end assembly to the new plate. I sure wish I had a TIG welder!

 

[Ianhill]

Yeah just checked that area on my frame and it has no rounded edge or holes to weaken it and they have welded a piece of round bar underneath to try take some strain, I hate the whole front end it needs to be chopped off and disposed of like nuclear waste.

 

[ElectricGod]

Yeah just checked that area on my frame and it has no rounded edge or holes to weaken it and they have welded a piece of round bar underneath to try take some strain, I hate the whole front end it needs to be chopped off and disposed of like nuclear waste.

The whole foldable front end was a nice idea, but in practical everyday use the scooter never goes in my car as it is my car replacement. Then I have an SUV with a big enough back area that I am able to put the scooter in without folding down the handlebars. Then, the wires running inside the down tube get pulled and stressed if I do fold down the handlebars. It's essentially a worthless idea all the way around for me and has always created slop since the parts dont make a perfect fit. At the handle bars I see about 1/2" front to back movement from the slop in the stock latching mechanism. I've added a piece of 1/16" sheet metal around the latch bar and that has helped, but after a while the piece of metal gets compressed and I have to replace it. The latching mechanism really wasn't designed for long term use or daily use like I give it...and certainly not ever intended for the power and weight I have on board now. It was a weakness in the design that was eventually going to fail and now that has started to happen. Maybe that's what I can do...just add a support inside the battery box that I can bolt in place. That steel I used for the back deck might work really well for this purpose and I could bolt it in place. A couple of braces made from that flat steel bar would do the trick. Maybe I'm not as screwed as I originally thought I was! Since I obviously need to reinforce the front folding section, I might as well just remove the latch assembly and come up with something much stiffer. Well it looks like the moped gets pushed back so my main ride can get repaired.

 

[ElectricGod]

I took apart the latching mechanism for the front end. I wont put it back on the scooter. Instead I'm going to get a couple of turn buckles to attach to the same places. I can crank them tight and that will pull out all the slack in the front end. My other thought was to use some bailing wire and then twist it tight. I might just do both. Once I had the latching mechanism apart I noticed it needed work no matter what I did. It wasn't going to break apart or fail, just not ever be slop free. The turn buckles and bailing wire will resolve all those issues.

I bought some square pipe last night. It's 7/8"x7/8" OD and fits right under that bent part in the mount plate. I was able to pre-spring the square pipe and pull out most of the downward bend. It had probably 3/16" bend in the plate right where that crack is. Now it's about 1/16". The paint job suffered from the c-clamps i used to pull everything flat, but it is mostly flat again. I repainted the back end earlier with some blue paint I found that's almost identical. I'll repaint this stuff too once I have it all in place. I'll add another section of square pipe in front of this one and bolt it in place similarly. That ought to make that section plenty stiff enough to not ever bend again. I had a bunch of 1/4" low profile screws from something from way back when so they came in handy last night. There will be another row of screw heads next to these ones to hold the other piece of square pipe. You can't see it, but the ends of the pipe are closed up so I was able to put a screw through the sides of the battery box into those closed ends too. That piece of pipe is not going anywhere!

 

[Ianhill]

I would have sayed use a brazing rod to shut the hole but with all that wiring and thats a lot of wiring it be a bit risky not to melt anything and its not going to expand with the bar in there, glad there was an easy fix and thats what's sorts the men from the boys stand back work what's wrong how to fix it just the halls now then and back on road ?

 

[ElectricGod]

I had 2 blown halls in the motor. That's fixed now, just need to put the back wheel back on. Fortunately the motor controller was unharmed. I should be riding again come Monday.

 

[Ianhill]

Glad its not to expensive thank god

 

[ElectricGod]

This is the final product so to speak.


The second support tube...it sits in front of the first one. The front plate is a little flatter and lots stiffer now.

The holes in the deck for the second support tube. And bolted in place.

And repainted.

 

[ElectricGod]

I went to the hardware store and found some turn buckles. I bought two different sizes just in case the smaller set was too small. I wasn't expecting this however. I got into my front yard, stepped on board and rolled 5 feet and the turn buckles bent out of shape. The smaller set is 1/4" thread and they lasted mere seconds. The larger set was 5/16" thread and they lasted a little longer, but those "I" bolts used to be closed and now they are stretched. After the 1/4" turn buckles bent out of shape I was looking much more closely at the turn buckles. I didn't try riding on the 5/16" turn buckles after I saw them stretch. I then went back to the hardware store and bought even bigger ones. The buckle part was too big for the space so I reused the buckles off the 5/16" set and tapped them for the 3/8" threads. I didn't have a reverse thread tap set so I improvised by cutting slots in the end of one of the reverse threaded "I" bolts and used it like a tap to create 3/8" reverse threads in the 5/16" turn buckle. It worked pretty well. Once I had the the heavier turn buckles made up, I put them on the scooter and then jumped up and down on the deck several times pretty hard and the turn buckles didn't stretch or bend. Just in case, they were not going to hold by themselves, I also used some bailing wire around a couple of posts that used to hold the old latching mechanism. Hopefully between the 3/8" turn buckles and the wire, it won't come apart. The front end definitely feels much stiffer with the latching mechanism removed. The only movement is in the stem now and the front suspension which not an issue.

This is the first couple of remains of turn buckles that failed. The 1/4" turnbuckles stretched out like they were made of butter. The eye bolts on the 5/16" set started to stretch as I was bouncing on the deck and so I decided they were just not going to work. Those "I" bolts used to be completely closed up.

 

[ElectricGod]

The ride into work went OK. There's no evidence of any stretching in the turn buckles. Admittedly this was a 5 mile ride so who knows long term, but there are several speed bumps and a few places where I go down a 40 degree hill. The real proof is cranking the throttle and hanging on tight. That will pull hard on the turn buckles.

 

[Ianhill]

Cracking idea I got some small threaded eye hooks lying around used for hoist lifting that will suit perfect for this I've sorted all of the play out of the stem now with something like this it will feel more than solid enough to add a bit of confidence to the ride.

 

[ElectricGod]

I checked it again at lunch and there's a tiny bit of play in front end. That might be just some play as things settle out. I'll check it again when I get home tonight (if all else fails just so I know it's not going to collapse on me all of a sudden) but I haven't used any locktite on the turn buckles yet so they may work loose as a I ride. I really wish the bolts had welded or lockable ends on them so they were more secure. The other upside to this change is that I have figured out how I am going to mount the 3220 on the moped...Use a couple of large u-bolts.

 

[ElectricGod]

I don't think the new turnbuckles spread any, but they came from the store partly open so last night, I squeezed then in my vice to close the ends up as much as possible. Stainless steel is so much stiffer than regular soft steel like the other turn buckles are made out of. I then put it all back together and came up with a better way to hold the turn buckles in place than bailing wire. The steel post that goes through the down tube was conveniently the right diameter to tap for 1/8" NPT threads. It's a common thread size in small plumbing parts so I tapped the ends of the post and then threaded a couple of fittings on after mounting the turn buckles. They hold securely against the down tube and can be easily removed with a wrench. Of course it's all locktited in place too. I also put locktite on the turnbuckle threads in case that's where the little bit of movement came from after 10 miles of riding yesterday. This morning riding in, the front end had zero play in it and checking it when I got to work was still perfect. Hopefully the two turnbuckles are a permanent solution. I still want a back-up solution in place. The bailing wire is not going to hold and as soon as it gets wet it will rust. I haven't found small turnbuckles that will fit in the space I have available and of course they wont be strong enough either. I'm thinking about using a couple of u-bolts instead squashed into a really long and narrow "U" or else use some flat steel and making something that fits the spot exactly. I have plenty of that flat bar stock I used for the back deck supports left over for this.

 

[Ianhill]

I noticed your folding arm is completely gone now I just done a fix for the folding mech but your lever is gone so no can do without it and looking at your locating pins it seems to be slightly different to mine, there seems to be a lot of small variation with these its like one child labourer builds one then Chinese whispers to the next how its done then he does his and so on down the line I bet the factory line bang them off the end of line no torque checks just twist throttle yeah it works paint chips whatever get stickers over them no one even blinks an eye lid straight on a container gone.