Nervagon's Directionless, and Doomed Build

[nervagon]

 

[nervagon]

Lookin good!

 

[nervagon]

 

[nervagon]

Stainless combo anti-sag, support, and bash guard fashioned from a BBSHD torque arm in the parts bin.

 

[nervagon]

you can see the steel bracket helps support the bottom of the motor.

 

[neptronix]

That ain't movin!

 

[nervagon]

That ain't movin!

I still feel like I need to fabricate a bracket for the bolt hole at the front of the motor. Securing the front end would really help make this sturdy build.

 

[nervagon]

 

[nervagon]

I’ve run into a chainline issue. With a near perfect chainline of 48, the primary gear is off by about 3mm. But the smallest spacer provided is 5mm. That means using the provided spacers, I can have a motor chainline of 45mm, or 50mm, while my chainring is 48. I’ll need to figure out some something… maybe finding smaller M6 spacers. I guess 10x 1mm M6 washers would do the trick.

 

[neptronix]

Interesting spacing problem.
I believe the motor sprocket can be flipped around?

... it's kind of nice you're always a spacer or two away from making it fit somehow

 

[nervagon]

Interesting spacing problem.
I believe the motor sprocket can be flipped around?

... it's kind of nice you're always a spacer or two away from making it fit somehow

The drive cog is already dished out, and needs to come out 3mm more. And speaking of the drive cog, the splined interface with the output shaft is not as snug as I would like. The tolerance is a little too loose IMO. I wonder if mating compound would help reduce the play.

 

[nervagon]

Fortunately I found 6mm x 13mm x 1mm washers in my toolbox. This allowed me to fine tune the chainline down to the millimeter. Basically I replaced a 5mm spacer from the kit with 5x 1mm washers.

 

[nervagon]

Not yet finished mounting the motor. I've worked out in my head a method to securely mount the front end of the motor to the downtube. This will utilize a modified in-frame bracket that I've ordered from Italy along with the chain guard. I won't be satisfied until the motor is completely secured tightly at all 3 through-hole attachment points, so I might as well just do it right up front. Basically, an ATV accessory mount will be attached to the downtube, and the modified in-frame brackets will bolt to that. That will mean that the short mounts attaching the motor to the bottom bracket are twice reinforced. I went out of my way to cleanly secure my BBSHD builds, and will strive for the same here.

I've also ordered a pair of Magura MT5e brakes that I intend to splice into the ebrake wires. And I've ordered an Ahearne Cycles Uprising Riser Bar which looks like an improvement over the Surly Sunrise, as the crossbar has been upsized for mounting of accessories. Also, the clamp diameter is 31.8mm, so I won't need shims or a BMX stem.

And since I will be running Schwalbe Marathon Plus MTB tires, the most heavy-duty and puncture-resistant tires available, I am debating lightening the rolling mass and rolling resistance with TPU inner tubes. I'm not interested with messing about with tubeless. TPU tubes are expensive, but I don't anticipate needing to replace them frequently. I think thick tires, and ultralight TPU tubes could be an excellent combo for ebikes.

 

[neptronix]

Dunno if you ordered the marathon plus yet, but the e-plus is out and does have higher protection. ( and higher rolling resistance )

 

[nervagon]

Dunno if you ordered the marathon plus yet, but the e-plus is out and does have higher protection. ( and higher rolling resistance )

IMO, the marathon e-plus is not an upgrade to the plus-MTB. Both are rated for high speed ebikes, but the e-plus have a street tread and a minimum listed tire pressure of 60psi compared to 30psi and more aggressive tread on the plus-MTB. They are just completely different tires.

 

[nervagon]

I created this 3D model to help explain to Bikee why I had ordered the in-frame mount. I tried to explain that I would only be using a small portion of the mount for something very custom, but I don't think they understood how I could be using it with the short mounts.

 

[nervagon]

The Uprising bar is a masterpiece.

 

[nervagon]

I think this setup has a nice silhouette, has nice balance, and looks very strong and secure. Instead of a weird bulbous mass jutting out off of the BB, it flows back onto the frame structure.

 

[nervagon]

Printing some test brackets for the front mount.

 

[nervagon]

 

[Vbruun]

Would a nursert in the frame be sufficient to hold the motor in stead of clamping around the downtube?

 

[nervagon]

Would a nursert in the frame be sufficient to hold the motor in stead of clamping around the downtube?

Maybe two M5 stainless rivnuts and a custom bracket would feel secure enough for me. But in my case, my downtube is perfectly sized for ATV accessory mounts that fit both 1.75" and 2" tubing, so I'd rather just have the security of the clamp.

 

[nervagon]

According to metric clearance hole charts, a close fit for a M6 bolt would be a 6.4mm through hole. The motor mount through holes on the lightest kit are loose-fit, or 7mm. IMO this is not optimal as it creates lots of slop. So when I mounted the front of the motor to the frame, I used these 6mm ID 7mm OD bushings. They create a snug fit.

 

[nervagon]

The custom parts needed to mount the front of the motor to the downtube. The center part is a modified atv accessory bar mount, and the 2 outer parts are the in-frame mounts from Bikee severely customized down to small brackets.

 

[nervagon]

Once the bar clamp arrived, it all came together pretty quick. The 3D printed test fit parts worked perfectly on the first revision, so I used them as the final template to make the irreversible cuts to the in-frame mounts shipped all the way from Italy.

Really happy with the installation so far.