Comment, criticize my build. But be nice I’m new!

[Drubieg]

Front sprockets are the problem with 219 chain and the my1020. They don't exist, so 219 is only useful as a second stage. I agree 219 would be nice, but it doesn't have huge advantages over #35.
My first attempted e-bike project was a my1020 on my downhill bike. I ran into so many problems that its still unfinished, but I'm also jealous of OPs ability to just build it and figure out the details later. Pedals, front brakes, that can all be solved in time if need be. A 2-3kw big bmx bike sounds like fun.

I hope you reconsider this part.

A lot of the fun is the building and learning!

I’m sure once I get familiar with this bike and have some miles on it, then the (controlled) mania will follow

 

[Hummina Shadeeba]

I did read the thread as a hunt for criticism. I’m often assuming everyone is looking for a faster vehicle

 

[DanGT86]

Thanks this is a good suggestion if it happens my 35 chain brakes a bunch

I was meaning more for the smaller pitch to allow you to optimize your gear reduction.

219 allows you high tooth counts in a small diameter. Its close in pitch to #25 but way stronger.

If I remember correctly #35 is non bushing chain and not super durable.

But if the bike works than keep riding as is. Ideally you want to gear for the speed you regularly operate in so you dont torture the motor.

 

[glennb]

Good thing there's no pedals ... or your knees would bash your chin. What's with the low saddle height?

 

[Drubieg]

Good thing there's no pedals ... or your knees would bash your chin. What's with the low saddle height?

Haha, i just raised the seat a bit last night… but only raised it to where my legs are straight when im at a stop and my feet are on the ground. When I add pedals back in that may change

 

[Drubieg]

I did read the thread as a hunt for criticism. I’m often assuming everyone is looking for a faster vehicle

It’s true I was, so says the title. I appreciate the feedback

 

[glennb]

Haha, i just raised the seat a bit last night… but only raised it to where my legs are straight when im at a stop and my feet are on the ground. When I add pedals back in that may change

Yeah, I reckon you should. It's hard to use your legs to absorb bumps if your arse is too low.

 

[Drubieg]

Yeah, I reckon you should. It's hard to use your legs to absorb bumps if your arse is too low.

And I ain’t got much of an arse

 

[glennb]

Bumps would hurt more then.

The parallelogram style suspension seatposts are pretty good. Ones like the Suntour NCX. Don't know if there's any available in 25.4mm though, which is probably what your post is.

 

[Drubieg]

What size chain ?
Here is an example image for a method to increase chain wrap on the smaller sprocket.
This image shows a rubbing block but a idler sprocket with bearing would be better.
A bigger rear sprocket with the correct bolt pattern to fit your hub may need to be custom made.
It's possible buy a sprocket "blank" then use the existing sprocket as a drilling template to make your own.

Blank Sprockets » Product categories » Azusaparts

Is the placement of the idler sprocket on one particular side of the motor rotation essential? Like could I put it on the opposite side that this diagram shows? For instance, this might help me with chain clearance of the rear brakes

 

[Hummina Shadeeba]

Is the placement of the idler sprocket on one particular side of the motor rotation essential? Like could I put it on the opposite side that this diagram shows? For instance, this might help me with chain clearance of the rear brakes

I don’t think can move the idler or it’ll be stressed with throttle. Could but be bad. Maybe ur controller can’t do regen but if it can you could skip the rear mechanical brake and just do electric brake. It’s nice. Get regen too. I’d get a vesc anyway.

do u need an idler sprocket? The distance between sprockets is far enough or can add a couple teeth on the motor side.

 

[Drubieg]

I don’t think can move the idler or it’ll be stressed with throttle. Could but be bad. Maybe ur controller can’t do regen but if it can you could skip the rear mechanical brake and just do electric brake. It’s nice. Get regen too. I’d get a vesc anyway.

do u need an idler sprocket? The distance between sprockets is far enough or can add a couple teeth on the motor side.

I was thinking the idler sprocket would allow more teeth engagement. I think my Kelly controller does have Regen ability but I just have to figure out how to wire it for that

 

[Hummina Shadeeba]

I was thinking the idler sprocket would allow more teeth engagement. I think my Kelly controller does have Regen ability but I just have to figure out how to wire it for that

I really like the two-way half-grip throttle and a strong regen rear brake. Then u can skip the mechanical rear brake.

I’ve heard it here and experienced it as well: under 16 teeth can get noisy. Really low teeth count is annoyingly loud. I see no reason not to go huge sprocket on back and 16 on front, no idler, regen rear, that chain they advised, and the monster 29” 160+ travel fork. Ok I’m done telling what I would do.


Seeming I’ll be beating you off the line in sf with my big 10:1 gear ratio drive. You could easily catch me .. if ..
But I think you won’t even know we were racing or want a race

 

[PaPaSteve]

Is the placement of the idler sprocket on one particular side of the motor rotation essential? Like could I put it on the opposite side that this diagram shows? For instance, this might help me with chain clearance of the rear brakes

Normal idler position is on the return side (slack side) as the picture shows.
If used on the drive side the mounting needs to be strong with a bearing sized at least the same as used in the motor.

Motor regen braking can be helpful . . . but . . . San Fransisco co-workers commuting on one wheels and e-skate boards without friction brakes would mention not being able to come to a complete stop on steep hills.

Guessing your desired commute path between the Marina and Financial District is partially on the pedestrian path between Fort Mason Park and Fort Mason Culture Center, the hill down to the sharp right turn at Aquatic Cove will require strong brakes.

 

[Drubieg]

I really like the two-way half-grip throttle and a strong regen rear brake. Then u can skip the mechanical rear brake.

I’ve heard it here and experienced it as well: under 16 teeth can get noisy. Really low teeth count is annoyingly loud. I see no reason not to go huge sprocket on back and 16 on front, no idler, regen rear, that chain they advised, and the monster 29” 160+ travel fork. Ok I’m done telling what I would do.


Seeming I’ll be beating you off the line in sf with my big 10:1 gear ratio drive. You could easily catch me .. if ..
But I think you won’t even know we were racing or want a race

Ha I can see you have a strong opinion on it. I’m gunna try and fit the 114t I bought while keeping the rear brakes and 9t front. I’m gunna try to get more engagement with the idler sprocket too. I’ve ridden it so far and the noise doesn’t bother me… but I’m in construction and am used to annoying noises all day long.

 

[Drubieg]

Normal idler position is on the return side (slack side) as the picture shows.
If used on the drive side the mounting needs to be strong with a bearing sized at least the same as used in the motor.

Motor regen braking can be helpful . . . but . . . San Fransisco co-workers commuting on one wheels and e-skate boards without friction brakes would mention not being able to come to a complete stop on steep hills.

Guessing your desired commute path between the Marina and Financial District is partially on the pedestrian path between Fort Mason Park and Fort Mason Culture Center, the hill down to the sharp right turn at Aquatic Cove will require brakes.

Good to know about placement.

Yea I was trying to figure out which path of travel I’d take around there. I think I want to avoid all the people and I’ll just go on a less traveled road parallel to the marina

 

[PaPaSteve]

Brakes.
One of the frustrating aspects of commuting in San Fransisco is pretty much every intersection has a stop sign or a stop light and not many bike lanes.
That's why the bike path on the Embarcadero works.
Curious, what project you working on ?

 

[Drubieg]

Brakes.
One of the frustrating aspects of commuting in San Fransisco is pretty much every intersection has a stop sign or a stop light and not many bike lanes.
That's why the bike path on the Embarcadero works.
Curious, what project you working on ?

Right now just building out 255 californias amenities space. I’m an electrician and mostly do commercial tenant improvement

 

[PaPaSteve]

From the Marina, Columbus street might work.
As a contractor in the city your probably avoiding rush hour by working 6:30 to 3:30 ?
Sorry for the personal questions.
Some days, I miss the city.

 

[Drubieg]

From the Marina, Columbus street might work.
As a contractor in the city your probably avoiding rush hour by working 6:30 to 3:30 ?
Sorry for the personal questions.
Some days, I miss the city.

No worries, yes I work 6-130 or 7-230. Did you work there as well?

 

[PaPaSteve]

Part of my task was to help build out the shop space(s) from scratch to setting up the machines and training the users.
Shop space at 5th and Howard evolved on to Pier 9 as the Autodesk Technology Center.
So yes, lots of construction and early morning hours.

If you ever get a chance to visit the Exploratorium the public is allowed to walk next door to Pier 9 to see trough the windows into the machine shop and robotic labs.

Another super interesting place to visit is the Autodesk Gallery at 1 Market St.

https://www.autodesk.com/gallery/overview

 

[Hummina Shadeeba]

when do you need an idler? I understand it’s for getting teeth engagement on the small cog and if has few teeth or too close to the other cog it’s needed but what tooth count or distance would that be? I only ever see them used on bicycles when trying to convert a bike with vertical dropouts to a singlespeed where you can’t just tension the chain pulling the rear wheel back.

 

[BiggKidd]

A

when do you need an idler? I understand it’s for getting teeth engagement on the small cog and if has few teeth or too close to the other cog it’s needed but what tooth count or distance would that be? I only ever see them used on bicycles when trying to convert a bike with vertical dropouts to a singlespeed where you can’t just tension the chain pulling the rear wheel back

An idler us often used to help keep the chain or belt engaged firmly on small sprockets making it wrap further around the small sprocket than it does naturally. Real small sprockets less than about 14-15 teeth force the chain / belt to pivot more than it likes which often causes issues with noise and climbing of the teeth.

 

[Drubieg]

when do you need an idler? I understand it’s for getting teeth engagement on the small cog and if has few teeth or too close to the other cog it’s needed but what tooth count or distance would that be? I only ever see them used on bicycles when trying to convert a bike with vertical dropouts to a singlespeed where you can’t just tension the chain pulling the rear wheel back.

I'm also using it in order to get chain clearance through the rear dropout. Or else with the large sprocket the chain is hitting the frame

 

[Drubieg]

Part of my task was to help build out the shop space(s) from scratch to setting up the machines and training the users.
Shop space at 5th and Howard evolved on to Pier 9 as the Autodesk Technology Center.
So yes, lots of construction and early morning hours.

If you ever get a chance to visit the Exploratorium the public is allowed to walk next door to Pier 9 to see trough the windows into the machine shop and robotic labs.

Another super interesting place to visit is the Autodesk Gallery at 1 Market St.

https://www.autodesk.com/gallery/overview

Sounds like a technical job, but fun! I'll be sure to check that out if we hit the Exploratorium, which we likely will with my 6 year old