Super sized stand-up Scooter project. Build thread

[Goped ESR750]

Been working on the motor mount. Probably ready to weld the mount together now. Will do this tomorrow. Few pictures of where I'm at.

 

[Goped ESR750]

Welded together the motor mount today. Should be no problem with this, looks pretty strong. I need to notch the motor mount so that it can go closer to the knuckle. I need to notch it the same angle as the bend, this will allow me to loose most of the bend inside the motor mount. The frame should curve around the motor. There will be several gussets reinforcing the welds once complete. Here is a few pictures of progress.

 

[Punx0r]

Nice looking welds 8)

 

[Goped ESR750]

Thanks for the comments. The battery set-up is going to be 8s lipo in a 2s4p configuration. Giving 20AH at around 60v. Going to be using a 400 amp kelly controller.

Made the notch in the rear of the motor mount today. Hopefully this should line up. The notch fits the 50mm pipe perfectly but I will have to wait til tomorrow to try it on the frame. The notch is now the datum for the front sprocket. I made lots of measurements to work out the rear sprocket position and then tranfer to the front by using the centre of the frame as a datum. Got to be careful that the notch is not too deep otherwise it will interfere with the motor aswell. Being unable to bring the scooter with me I have just relied on the accuracy of my measurements and marking out. So may well be making the motor mount again

Here is a few pictures of where I am at.

 

[Goped ESR750]

Welded the motor mount to the frame today. Am happy with the position, the motor is now as far back on the frame as I can expect to get it. Had to raise the motor slightly of the frame by about 10mm to clear the bend so the notch which fit tight on straight pipe. Made some gussets to weld in the gap and to support it in all positions. Here is a few pictures of where I am at.

 

[Goped ESR750]

Been welding again, now have the motor mounted, will need to make an idler sprocket to guide the chain plus a tensioner. Got handlebars coming Monday. Here is a few pictures of where I am at.

 

[Goped ESR750]

Tried the Go-Ped board on my frame for size. Seems to fit nicely. Will either use a new goped deck, or at least make one using my deck as a template. Certainly start looking quite Go-Pedy with the deck on, which is good as my inspiration was my original Go-Ped hence why I went through the trouble of making everything single sided swing arms, just like my Go-ped.

Been deciding which way to guide the chain through the frame, it either has to go under or over the suspension knuckle. The chain looks far betting going under the suspension knuckle, but being underneath the pivot point of the suspension does this mean that the chain will be fighting the suspension when it pivots?? Or is it perfectly fine to route the chain underneath the pivot point. Any opinions??

My feeling that it would be better to route it over the knuckle so that when it pivots it does not tension again the load side of tha chain.

Here is a few pictures of where I am at.

 

[amberwolf]

Either way, having anything that prevents a straight chainline across the load side of the chain is going to put a lot of stress on your idler, whether you do it above or below the suspension pivot.

Doing it below the pivot does at least increase wrap on your drive and driven sprockets, so you get a minimal advantage out of it. Doing it above it decreases chain wrap a bit, making a minimal disadvantage.

Your idler will still have to have a tensioner that reacts along with suspension movement to keep the chain taut enough. I don't know how your suspension reacts to say which way might be better regarding that, other than to say the further your suspension moves then the more wrap you will get with it under and the less wrap with it over, at max bump.

 

[E-racer]

 

[Goped ESR750]

The plan is to go under the knuckle, and have a sprocket coming off the knuckle guiding the chain down. I will then tension the slack side of the chain outwards with large spring, towards the ground. I may have a third sprocket just in behind the drive sprocket to ensure wrap around is maintain when the slack chain is pushed outwards by the tensioner.

The wheels are going to get new tires and also fresh black powder coat once the frame is finished and ready for powder coat, frame colour is probably going to be bright orange.

Received the handlebars today, so tried them for size. Few pictures of where I am at.

 

[E-racer]

If you build a two idler setup like I posted you wont have to deal with a sprung tensioner.

 

[Goped ESR750]

Can you explain the design a little and how it would fit my scooter. As I can't really see how what is picture would fit and work. Will always need a spring tensioner regardless because the pivot point of the suspension isn't in line with the chain every movement either increases of decreases slack on the chain. To ensure I don't have a war between the suspension and chain surely I will always need a sprung tensioned oversized chain.

 

[E-racer]

The idler carrier rotates on the same axis as your suspension knukle. The idlers contrain tthe chain to the same width as the motor drive sproket. This allows the swing arm to move up and down without tighteneing or loosening the chain. Essentially this design does the same thing as adding a double sproket on the pivot axis and doing a 2 chain jackshaft setup.

 

[E-racer]

You dont want the tension side of the chain under the knuckle. The motor will try to pull the suspension up under load. Everytime you hit a large bump the suspension travel will shock back torque through the chain into the motor.

 

[Drunkskunk]

why not revise the pivot point as the shaft of a jack shaft? A bearing hoding 2 gears on that shaft would allow a chain from the motor to the pivot, and a chain from the pivot to the back wheel, eliminating chain stretch during suspension movement, and the stresses a drive chain under tension would give an idler.

I don't have an illistration, but it's how some DH bikes, along with the Stealth Bomber Ebike do it. 2 chains, and the suspension point is also a jackshaft.

 

[E-racer]

why not revise the pivot point as the shaft of a jack shaft? A bearing hoding 2 gears on that shaft would allow a chain from the motor to the pivot, and a chain from the pivot to the back wheel, eliminating chain stretch during suspension movement, and the stresses a drive chain under tension would give an idler.

I don't have an illistration, but it's how some DH bikes, along with the Stealth Bomber Ebike do it. 2 chains, and the suspension point is also a jackshaft.

I like that thought as well. The issue is see with it is that you will have to keep two chains tensioned properly.

 

[Goped ESR750]

Should the two sprockets move with the suspension or be able to move independently? This is doable, the chain would have to be over the top sprocket not under it though.

Jack shaft isnt really doable would be as good as starting again to be able to achieve that now. It doesn't need to be perfect engineering solution, Is running the chain under with a slack chain and tensioner really so bad, because looks far better.

 

[Goped ESR750]

Realise what you mean now. Two sprockets pivot with the swing on the same pivot point to maintain chain distance. The only difference is that the chain should be running over the top of the top sprocket? Is this correct?

 

[Goped ESR750]

The idler carrier rotates on the same axis as your suspension knukle. The idlers contrain tthe chain to the same width as the motor drive sproket. This allows the swing arm to move up and down without tighteneing or loosening the chain. Essentially this design does the same thing as adding a double sproket on the pivot axis and doing a 2 chain jackshaft setup.

Something like this?

 

[amberwolf]

@Goped ESR750: All your photobucket images are currently unavailable; it says "bandwidth exceeded". If you want them to always be available to thread viewers, I recommend adding them directly to the posts in the thread as attachments. You can still leave the PB versions in the thread too, then just stick the attached copies on at the end of each post as "backups". You don't have to place them inline.

 

[Goped ESR750]

Should be fixed now. Thanks for the advice, I'll try then when I got some time.

 

[E-racer]

Wow! You have been busy. That is not quite what I had thought of. I did not realize at the the top of the suspension the knuckle was higher than the chain (granted chain was pulled tight/straight). Does it work how it is setup now? Ideally you need to constrain the chain to the width of the drive sprocket at the knuckle.

 

[Goped ESR750]

Tensioner seems to works, have not had a real test on it yet as I still have nothing to power the scooter with. I think the tensioner works better if it is tight with the top sprocket before 12 o clock. Have had a busy few weeks. Got new hoses for the brakes, and bled them. Only to find that the rear hose is too short, I ordered replacement ones for the scooter I took the brakes off, I think where I need to run the hose low it makes the route further than it would of been on the scooter. Need to order a 2.5m custom hose and replace the rear line.

Have ordered the majority of the electrics now. I am using turnigy 8s 5AH nanotechs. The configuration should be 2s4p giving me 60volts and 20AH. The monitoring system is two handlebar mounted cell logs. One for each bank of parrelled batteries. These means that each the cell log will monitor four paralleled cells.

The banks will be charged in the same manner. Am using amphenol plugs for the monitoring and balance circuit. Will simply unplug to switch the cell logs off. Similarly the same port on the battery box will be used to balance during charge.

I hope for a four mile range. I opted for two chargers so I can charge both packs at the same time. They are 10AH charges so should be looking at a very quick charging time.

Have not yet received the batteries which is unfortunate as I want to start work on the battery boxes. This is pretty much all that needs to be done to finish the frame. I cut out the deck with my plasma cutter today, used the original go ped decks as a guide. Which makes my decks the width of the nozzle larger than the original go ped. Think space may still be a little tight, especially as the controller is a lot bigger than the last one I used. I selected the waterproofing tab on the controller and plan on mounting underneath the motor mount, external to the battery boxes. Or on top of a rear mud guard if make one.

Got three weeks off work now so progress should be quick.

Here is a few pictures of where I am at.

 

[Goped ESR750]

Been doing some electric work today. Soldered a few sockets and crimped the other end to fit the cell logs.

Also made up one end of the monitoring plugs. I have ordered some stainless steel braided sheath to go other the cable to make it look better, so won't make the other ends off until this arrives.

The controller needed two led's on the display, so added these too.

Few pictures of what I got.

 

[Goped ESR750]

Been working on finishing the electric for the dash box. Added a pot to adjust the regen, a key switch and a small switch that put a pre charge resistor across the contacts. In the manual it just shows in the diagram it always being on, but it draws 10W so decided to make it switched. Just push it for a few seconds before I turn the key to bring the main contactor in, this stops any sparking.

Few pictures of the set-up.