Mini Hiryuu - Mid power ebike

[neptronix]

Thanks for the inspiration, maybe it is finally time to add skill #2,951 to my repertoire instead of continue to resist adding a new one to the pack.
Can you recommend me a spoke wrench, and also, i imagine i need a stand of some sort too?

 

[99t4]

I took a couple of my spoke/nipple to the FLBS and tried their spoke wrenches and bought the one with the best tightest fit and quality. Turned out to be the iconic Park SW-0.

SW-0 Spoke Wrench — 3.23 mm

This professional-quality spoke wrench is sized for spoke nipples with 3.23 mm (0.127") wrench flats and built for a lifetime of use.

www.parktool.com

Didn't use a stand. My upturned bike was the stand. Used zipties for the "feelers." Worked great. If I was to do several more wheelbuilds or more often I would get a stand, but not necessary for a one-off or even few-off projects.

The other helpful item was an old sharpened spoke used for nipple placement and insertion.

Next time I will use the moly grease that Chalo recommends. Should be less messy than the wheel bearing grease I used.

 

[neptronix]

Of course it's a park tool.
Thanks for the tips!

 

[neptronix]

So i bought a ubox vesc from spintend and now i have the same symptoms i had with the phaserunner:

- motor spins fine upside down
- upright, we have random power cutouts / jittering when using the throttle, ranging in frequency.
- motor randomly engages itself for a few milliseconds.

Interesting how we don't get random unexpected engagement of the motor with the infineon square wave controller. The infineon won't stutter, it either goes when i hit the throttle or doesn't... or it abruply stops.. none of this crazy on-off nonsense.

Every time i encounter this stutter it loosens the all axle torque arm and starts smacking.


So okay, let's downgrade to sensorless.

I tried running the VESC sensorless with the VSS ( vedder sensorless start ) algorithm. It has occasional stutter on startup, but is otherwise really smooth, predictable, and quiet.

I tried HFI mode but it just grumbles and shakes.

VSS it is! the only problem is i cannot get regen working no matter what on the Ubox VESC; i'm contacting tech support for help.

But at least we ruled out a halls problem and i'm surprised to get a motor with bad/intermittently bad halls out the gate. I've contacted grin for support to see if i should do the repair or ship it back.

No word on this RH212 shipping to me. Grin must be really busy.

 

[neptronix]

ps here's how the spintend controller rig looks. I think i might be able to fit a 4S 20AH RC Lipo in the left area if i can get longer cables to move the controller to the right area.

 

[neptronix]

pps
Got back from a ride on phaserunner level power ( 90A phase, 35A batt ).

The low end torque is weaker but the mid to high end is stronger ( almost thrilling )
Probably involves tuning all these strangely named FOC parameters to change that;

This ES post details a potential fix for the weak low end torque i'll try tomorrow.
VESC Tuning Advice, Poor Acceleration compared to other controllers

Got Amy from spintend on the line to help me solve the regen problem. I hope the answer isn't that regen doesn't work in sensorless mode!

 

[neptronix]

Bumped it up to 40A batt 100A phase, with 10A of flux weakening, and got the regen working!

Oh i love this controller, the regen is better than anything i've ever used, i can come to a complete stop with just the regen, unlike every other ebike controller i've used.

 

[neptronix]

RH212 just shipped and will be here tomorrow!

 

[neptronix]

Motor's here! nice unit!!

 

[neptronix]

Damn dude.. at the same power level ( 40A batt, 100a phase, 52v nominal ), the RH212 feels notably stronger and is entering the thrilling zone of power.. it really really reminds me of my leafmotor 35mm.

It's around 80F at 8:30am here and i gave it some rips up and down the block.. temp rise seems to be approx. half of the grin all axle. I can barely feel any heat.

I can tell this motor can take a lot more power and i'm thinking back to the time @Cowardlyduck was telling me it was a lighter contender to the leafmotor. Well, i'm having flashbacks bout those wonderful experiences on the leaf!

Up in the air, the motor has no spaceship-like whirr when spun, it's completely silent. With the VESC controlling it using hall sensored mode, all i hear is faint buzzy grunts at certain speeds when at full acceleration.

The really unfortunate part of this motor is that it just barely tips the scale into 'too heavy' and introduces a wagging rear end as you're carrying it.. it is now burdensome to carry as well. It's interesting how the difference of just 4.1lbs + ~1lbs of torque arm hardware just instantly changes the bike to 'too rear heavy' despite my dogged efforts to shift more weight the front.

I love the power but the axle on the RH212 is on the narrow side and a poor fit with the ebikes.ca torque arms; which are normally very snug. There's at least 3mm of total motion within the slot itself. This is a long term concern that could only be fixed with clamping dropouts or keeping the power level at this power level or slightly below ( Which BTW would be very efficient, so that's a plus )



Eating whatever i wanted ( not good for me ) while i was a stress case starting two companies during covid put 90 pounds on me. I'm back on fulltime keto and I've lost 30 of those pounds since February and an extra 60 remain.

Going from a current 251lbs to at least 200lbs should cause the all axle to accelerate 20% quicker and therefore the heat buildup will be reduced significantly. It will feel 20% faster at my lower weight which is larger than the torque differential i'm experiencing with these two motors.

I think the RH212 is a good temporary clydesdale motor and would be a lot of fun hot rodding, but this is just an A-to-B bike and i don't need these gobs of power. If i beat up the dropouts, it's fine because i can put the all axle on, haha. I'm looking forward to switching back to the All Axle once the summer heat dies down and my weight is lower.

I would like to at some point switch this frame out for one made of chromoly; between the fat tires on lowish pressure, the seat suspension, and the seatpost suspension, switching out the frame would be the final step in comfymaxxing the hardtail to prepare it for ~38mph duty. But i think i'll rock this cheap frame for a while.

 

[Cowardlyduck]

Kinda know what you mean Nep...the RH212 is a bit hefty....but on my Phaserunner at 60A battery (52V) it really comes alive. so I find the tradeoff worth it. With a bit of Statoraid it rarely overheats also.
That being said, my other bikes with the same motor that max out at 25A batt, are suffering a bit from the heft. An all axle would be the better choice, but at the price point they come with....I think I'll stick with my 212 and live with the heft. I came from a 27mm Golden motor (9C Clone) to the 212, so I'm liking it!

Could be worse.....remember the Crystalyte HS40xx, and the old 5403 behemoths! The MXUS 3K motors are also pretty hefty, but unlike these they can punch up to 10KW+ with ease....I've even run one at repeated 14KW peaks.
What we need is more competition in the 3-5kg (6.5-11 Pounds) hub motor space that can still easily reach 2-3KW. That is where the all axle lives....but so far, it's the only one.

Cheers

 

[neptronix]

BTW i flipped the bike upside down without a battery in it and was still shocked at the weight of the RH212, the difference in wheel weight is actually 6lbs.

I don't like this at all, when i add 4S 20AH batteries in series to get to ~66v, the bike would be murderously heavy. I've decided to go the other direction and make the all axle a primary motor and just live with the halls issue until the maxaraya is up and running solidly.

Another thing i notice is the drama of getting the wheel off, whereas the all axle is easy AF to put back on, i just need a tiny hex wrench and that's it.

The thing has spoiled me, lol.

I don't like the idea of putting fluid in my motor but i think ferrofluid is the right call for the all axle when abusing it at 2.25kw.

An all axle would be the better choice, but at the price point they come with....I think I'll stick with my 212 and live with the heft. I came from a 27mm Golden motor (9C Clone) to the 212, so I'm liking it!

Yes, i notice that is a problem for many and i wish this motor came at a lower cost, i think the economy of scale is too low ( 100's of units sold, not thousands ) right now and hope sales can drive more efficient mass production.

What we need is more competition in the 3-5kg (6.5-11 Pounds) hub motor space that can still easily reach 2-3KW. That is where the all axle lives....but so far, it's the only one.

I so agree, there's lots of efficiency/power hacks just sitting on the table for some DD manufacturer to pluck ( thinner lams, hairpin construction, hollow axles, etc ) and now have the best motor. There just doesn't seem to be interest in creating excellent products in this area and i'm glad we at least have grin innovating.

 

[neptronix]

The trunkbox is done-ish!
That cheap super adjustable ebay rack worked out great!



The box is a $10 ammo can from Harbor freight.
I used some thick rubber at the mounting points to help isolate vibrations.. since we don't have rear suspension.



The connection is part zip tie, part bolt with fat washers added. The connection is very strong, no wobbles, no problem lifting the bike up by using the box, and also, there is plenty of distance between my legs and this box, if it was just 1 inch/25mm less tall, i could move it towards me more and get away with it for an even better center of gravity.

Slots were made using a drill and a lot of side to side reaming.

Could use a thick pad to help isolate stuff in the box from a rickety ride..



There's an adequate amount of opening to make up for the fact that we're behind the seat a bit, I'm happy with this for now!

 

[E-HP]

Oh man. Please don’t make another video, or I’ll be forced to build another ebike

 

[neptronix]

Can't promise that, sorry! i've got a lot of things to address w/video now that i have some time for hobbies!

 

[neptronix]

Just been scorching hot in Utah, weeks where it's hanging out in the 100's and despite my best efforts, my office gets up to 84-85F and i'm wiltering!
That and the usual high pollution we get in the summer has had me cooped up and off a bike for weeks now.

Looking forward to this short break we get over the weekend to get some riding in.




As for Mini Hiryuu, what remains:

1. Triangle bag can move at least 1 inch forward and the support bar can be reworked so that we can actually fit another 52v 19.5ah battery on the bike to the left of the triangle if i wish. Not sure which direction to go next.
2. Add flatout and ferrofluid to the rear wheel.
3. Get the all axle's temp sensor working with the VESC.
4. Lights
5. Aerodynamic improvements

 

[E-HP]

As for Mini Hiryuu, what remains:

1. Triangle bag can move at least 1 inch forward and the support bar can be reworked so that we can actually fit another 52v 19.5ah battery on the bike to the left of the triangle if i wish. Not sure which direction to go next.
2. Add flatout and ferrofluid to the rear wheel.
3. Get the all axle's temp sensor working with the VESC.
4. Lights
5. Aerodynamic improvements

I was looking to see if I missed an update, but then looked at today's weather report, not as hot, but still hot. Anyway, on the pic of the bike's side view, I was wondering if you have enough clearance between the seat and ammo box when the suspension seatpost is compressed. I don't know how the NCX compresses though (my Thudbuster goes down and back).

 

[neptronix]

Our weather in Utah still looks like that.. 100's, upper 90's..

I've started waking up at 6:30am lately so i can get some miles in whenever the air isn't thick with the west coast's smoke, which hasn't been often. All that riding has been on an acoustic bike for exercise purposes.

I was wondering if you have enough clearance between the seat and ammo box when the suspension seatpost is compressed. I don't know how the NCX compresses though (my Thudbuster goes down and back).

This is a good question, i measured the distance between the seatpost and box and it's only 32mm.
However, my seatpost goes backwards more than it goes down. So it may work.

I'm betting i don't get away with that positioning when i get my thudbuster LT though and that's something to think about!

 

[E-HP]

That's why my rear bag is mounted so far back that the last 2"-3" hangs off the back of the rack. The nice thing about the adjustability of that rack is that you have plenty to work with and can move it back and keep the clearance to the rear tire the same, just by loosening a few hex bolts and pushing it back.

 

[neptronix]

Lol true, i might not have to re-mount the box.

I do like the box being pushed inwards as much as possible, not just for weight distribution, but also because i can use the rear part of the rack as a handle to pick up the bike. The handle is at a perfect height too.

What a killer recommendation this rack was!

 

[neptronix]

The heat is finally dying down out here.. if i can get out of the house at 7am, i have about an hour of riding before we hit ~83F.
Right now i've just been taking out the pedalbike but ebike season is coming shortly..

So i gave Mini Hiryuu some love to prepare.

Went from a 135mm handlebar stem to a 150mm stem and dropped the handlebars so that they're just barely higher than the seat. It's just barely long enough that i can get into a tuck position.



A nice bonus is that it's easier to take the hub motor off and chuck it into a car with the much lower positioning.

I extended the battery bag brace so that the fitment is tight. I'm happy i was able to get the battery another inch forward. I'm hoping this results in less battery motion ( not severe right now, but any amount of it is unwanted )

Remaining work:

1. 4S battery
2. Downgrade rear 2.2" to 2.0" for a smidge more torque
3. Thudbuster LT now that i'm less fat and within the stated weight limit
4. Add flatout and ferrofluid to the rear wheel.
5. Lights
6. Aerodynamic improvements

OK, everything else is straightforward except the aerodynamic improvements part.


The ability to get into a quality tuck seems to benefit this setup a lot..



VS not tucked:



This makes me wonder if the bike would benefit from some conservative aerodynamic fairings at these speeds too..
More research needed!

 

[neptronix]

I wanted to finally take a ride tomorrow..
..i spin up the bike, and the VESC is running backwards so i have to program it again to get running. Annoying.

By spinning up the wheel by moving the cranks, i notice a clunking that gets progressively louder above approx 350rpm.
So this motor's got two problems now -_-


..and the RH212 has way too narrow of axles for me to feel good about pushing high power into it.

Luckily Grin sells these, which have a clamping dropout, negating the issue.. i've ordered a pair.


I also ordered a pair of 24 x 2.0" tires because i'll eventually have 90mm of seatpost travel and won't have to rely on the reduced air pressure trick.

Should be back on the road in 1-2 weeks!

 

[Cowardlyduck]

It's great to see grin doing those clamping dropouts.....it's the only guaranteed method to stop movement over time when using regen....something I also figured out many years ago when I had a small run of replacement clamping dropouts manufactured for the Stealth bikes after many users (including myself) had problems. The final straw for me was the time I had my rear wheel literally fall out from loosened axle nuts caused by regen rotation.

Cheers

 

[Chalo]

It's great to see grin doing those clamping dropouts.....it's the only guaranteed method to stop movement over time when using regen....

There's a much easier remedy for that problem.

 

[gromike]

I do believe regen braking is worth the extra trouble. I have been running a Grin motor with their integrated torque arm and it works!