Razor e300 ultra. Technical guide

ElectricGod said:

For dual wheel drive, get the dual VESC 6.6. You have to program each one individually, but the dual is cheaper than 2 separate VESC 6.6's. They come in 100 and 200 amp versions with a max of 60v.

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If this was 20s with the same current handling then it would sell in massive quantity, I can't fault the single 60amp version it works well but really I would say the software development has been the hard work the fact that copies are allowed to use it for that i give respect to the author Benjamin he must be a top guy.

Ianhill said:

ElectricGod said:

For dual wheel drive, get the dual VESC 6.6. You have to program each one individually, but the dual is cheaper than 2 separate VESC 6.6's. They come in 100 and 200 amp versions with a max of 60v.

Click to expand...

If this was 20s with the same current handling then it would sell in massive quantity, I can't fault the single 60amp version it works well but really I would say the software development has been the hard work the fact that copies are allowed to use it for that i give respect to the author Benjamin he must be a top guy.

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I know...flipsky didn't go far enough IMHO...they really ought to make a 100v max version. I bet with a little bit of effort, that the controller can be modded for 100v. I'd have to buy one, but I bet the onboard DC-DC converter can be reworked for more voltage. Replacing the caps and mosfets for 100v ones isn't really hard.

Oh well...their loss!

I know of 3 VESC based projects that are close to completion that are 100v or 150v. The one that really has my attention is running TO-247's and 150v in 12 fets...should do 15kw or more.

A200s vesc does 16s reliable and can be sourced for £300 3 week back order and does 12kw max could be a good contender for blasting a small scooter about but there are few you mentioned that could have easy route to upgrade so they are interesting to say the least.

This build stalled for quite some time I've been trying to find a suitable fork that is not to heavy but has the correct width, so I chopped the original fork up and centred the new front wheel with disc attached to give me the correct width I needed and the dropout happened to match that of a fatbike fork, 135mm chuffed with that I measured the hell out of that front hub to get it spot on and it looks like the industry agrees 135mm small as u go on this width of tyre.

Due to the the handle bars being upgraded to SCS clamp, I no longer need a threaded steerer this was also a concern stoping me modding the original fork so I kept it in my mind and found a 26 inch fatbike fork with a threadless steerer that was 15mm to longer so I have the option of upgrading the bottom bearing from 1 1/8th to 1.5 and use a cup and fork convertor for a tapered steerer this will give me added strength around the bottom bearing but I'll have to check first as it will push the front of the scooter up a little by the height of the bearing cup adapter so I may run a 1 1/8th I 'll have to suck it and see on this one I want to keep the scooter low and compact don't want it looking lanky and strength is fairly decent even with out the added bearing gurth 1 1/8th is good enough for the fat bike.

Then to finish the job proper all I need to do is shorten the legs on the steel yellow set of forks with the greys lower tabs, add a disc brake hanger and powder coat black, so it's easy enough no major weaking or invasive cutting happening, the original forks even though useless and for the scrap bin have served well as a template, I wouldn't have spotted the similarity with out doing a crude mock up.

Got my fork today well happy turns out to be just what i needed much more heavy duty and it has a a little bit of forward rake should be abit less turn responsive but more stable at speed which is ideal for such a small wheel that is light I will have no issues with turn in a wee bit of weight will help to keep pin point control.

I've been taking measurements for the frame and brainstorming on paper while looking at frames for the design and look I going for the drawing don't cross over to well and ain't to scale I ain't no artist but it's to help me picture it all on my head and imagine clearance issues I may have and how I'll go about making the frame itself in going to reuse the fork after all as the outrigger legs to add strength to the headtube simular to the new boosted scooter.

Been checking through my tyres to make sure I have clearance and marking the fork ready to be cut as u can see it's going to be a thick beast compared to the stock fork.


I measured the razors headtube and it's 110mm there's lots of versions of the scooter over the years and this measurement drops on some to 100mm to save metal scabby bastards shorten the bearing race distance and stability so ive found a 130mm steel headtube and I'm going to use that i hsve a long enough steerer tube it will help make my bars feel stiff, by the end of it I'll of chucked most the razor out used none if it's parts and cut it to bits as a template

Came across this dirt scooter while looking at differing forks and really liked how the axle is attached with no tabs welded on so ive gone with that only got to weld up the disc brake attachment.



I've spotted that carbon forks use a compression plug rather than a star nut, with the scs compression system I think this will be the finishing touch to a strong front end but I'm gonna have to dig about for the correct one I need.

Works a treat just need to get some 12mm id tube to make the bearing spacer in the hub and the exterior spacers, I can move in to the frame now.

Cut the disc hanger of the old fat fork and test fitted, the brake aligns up nicely quick sanding and remove old cable hanger and it's ready to be welded up along with the washers on the axle to create the tang so the axle has good strength to the fork.


I must of spent 10 hours designing a frame that's as compact and strong as I can make it with an active cooling channel underneath that's protected from direct hits, The controller can be sealed from the elements in the battery box but cooled with heatpipes same for the bms both will be stacked close together.

I'm finalizing the design on paper and I'll get some pics up of what I intend on, I've designed the scooter to use my existing batterys and also 16s6p or 102 21700 cells, a Bluetooth 12 fet controller and 24s 100amp bluetooth bms so i can seal the lid and external charge there will be a dc breaker on the bms but that will need the lid removed if tripped so I'm going to choose this one carefully for what I will require, 120v 60amp single pole more than likely

what axle length and size front and rear? I have two scooter hub motors sitting but its the small ones

135mm front dropout 150mm minimum on the rear with the hub I'm using but it needs torque arms so the axle width is 235mm I'll trim it down to around 210mm I imaging when it's done giving 30mm each side for torque arm that attaches to frame plus a nut and washer (15mm)

I've got a bigger fatbike fork that's 150mm with a tapered steerer and a matching headtube but it's a build for the future I'm finishing this one soon as I got time progress is being made be it slow hopefully before Xmas I'll get a grip on it.

So taking a razor and making it into the Go Ped ESR.

Smaller in length bit more cleaner handlebars but simular weight and stance.
Toying with a drift trike build then nice light small alu one.

cheapcookie said:

what axle length and size front and rear? I have two scooter hub motors sitting but its the small ones

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Stock razor front fork uses a 125mm dropout with the 3.00 tyre and 115mm with the 2.50 all the frames I've seen have had a 140mm rear dropout no matter the ture size and there's upto version number 35 in the UK so there's lots that can catch out little differences in headtube length, handlebars fold on early models but not on later ones, I find the latest version is best overall from stock but any dark grey version would do for a taredown they all have the same frame, just different fork and bar lengths.

Like I've worked on the assembly line I've been in so many of them.

Been potching with the frame when I got spare few minutes. Ive added some side support for the downtube and notched the frame out for a cable run underneath.






I'm gonna have a bash at building the battery box Into the frame rather than removable it will add some strength to the frame for little weight penalty.

Had an old Kelly controller donated too me dead to the world it had a thick heatsink so I cut the shell down and removed the fins around the perimeter to create a fixing lip this then will fit the rear of the battery box to dump heat with the passing air.
I've also made two extra supports to catch the front of the battery box, I've ordered my metal and lots of other goodies keep putting in a few hours here and there and soon enough I'll have it rolling about.

Nice work and progress. What does the added lacing on the motor do? Seems that coating is for anti dust.

ESR_RSE said:

Nice work and progress. What does the added lacing on the motor do? Seems that coating is for anti dust.

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dust as in anti rust, yes this wheel is close to the ground water ingress is a big issue when the heavens open the hub is close to all the spray and road salts dirts and whatever I'm riding on.

When the current in the windings is high from a stand still the windings will move in the slot if free too repeling eachother, watch the leads on a decent battery spot welder when the high current flows the leads repel same happens in the motor but there less current so it's not so violent, all im doing is helping preserve the motors life a little.

Cheers, I'll get it there slowly but have summat decent in the end.

Oh wow I did not think of that. Did you follow a guide and what materials were used in that extra durability step?

ESR_RSE said:

Oh wow I did not think of that. Did you follow a guide and what materials were used in that extra durability step?

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Motor conformal coating and then some nylon string to keep the end turns tight make sure it's clean enough to eat your dinner off before starting, in all fairness the motor is not wound to bad the end turns are a bit how's your father but the slots are packed well nice and tight.

If i wanted to make the motor fast as possible no care for life I would use ferrofluid and encapsulate the end turns to the stator but sealing the stator both ends means it's likely to corrode internal over time with heat cycling and no free air movement.

Made some new plates to mount the rear wheel took me long enough only got basic tools but i got there in the end, well over 10 hours in both parts.

I used 15mm × 65mm steel stock chopped it up to suit, integrated the disc mount and torque arm into one plate, an m8 bolt locks the axle in place on both sides and I've thinned them out as much as I can to get the final weight well within acceptable range not heavy at all compared to the block I started with.


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nice build so far ! i made a big one too ! stretched the deck, forks, tail. customized the handlebars to bmx style. 12" tires, 48V 20Ah, 500watt contoller. i ride mine all over NYC.

brianallmotor said:

nice build so far ! i made a big one too ! stretched the deck, forks, tail. customized the handlebars to bmx style. 12" tires, 48V 20Ah, 500watt contoller. i ride mine all over NYC.

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I like it, reminds me of my first scooter that got me hooked same colour used it as a work horse, it was a 3000w brushed motor good 6 year ago now this thing been over a year in bits nearly it's got to be done before new year need to clear my head of it.

spinningmagnets said:

I didn't know something like those split wheels was available, what a brilliant idea. I have changed many flat tires in my life, and having that would have been awesome.

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It is truly awesome, cannot believe I've never seen something like it before...

I guess the downside is some additional weight(?) but it's still bleeding cool.

Nice build too :thumb:

boars said:

spinningmagnets said:

I didn't know something like those split wheels was available, what a brilliant idea. I have changed many flat tires in my life, and having that would have been awesome.

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It is truly awesome, cannot believe I've never seen something like it before...

I guess the downside is some additional weight(?) but it's still bleeding cool.

Nice build too :thumb:

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Cheers boars, id like to see an axial version of this hub I'm sure with decent design theres room for north of 8kw in this package and still have some breathing space for improvment, only issue with these hubs are the tyres there's a massive flood of cheap unbalanced out of round stuff lurking so best to search for mini moto racing tyres by pmt they are tubeless radial and theres even road compliant tyres not that it makes much diff on an illegal ride but its piece of mind for the rider.