Go Back  Bike Forums > Bike Forums > Electric Bikes
Reload this Page >

Limiting Mid Drive to Class 2

Notices
Electric Bikes Here's a place to discuss ebikes, from home grown to high-tech.
 Magic Cycle

Limiting Mid Drive to Class 2

Old 07-17-22, 08:03 AM
  #1  
eric1514
Newbie
Thread Starter
 
Join Date: May 2007
Location: Boise, ID
Posts: 55

Bikes: 1968 Raleigh SuperCourse, 2016 Trek Marlin 5

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 2 Times in 1 Post
Limiting Mid Drive to Class 2

Hi all,

I'm thinking about converting a Trek Marlin 5 into an ebike with a 750w Bafang mid drive motor. I will use this bike mostly around town but I want to take it camping and ride some easy trails with it, also. I'm assuming I can, with programming, limit the top speed to 20mph. Would doing this then make this a Class 2 ebike and therefore legal on State and National Park trails?

TIA,
Eric
eric1514 is offline  
Likes For eric1514:
Old 07-17-22, 09:06 AM
  #2  
2old
Senior Member
 
Join Date: Jul 2014
Location: socal
Posts: 3,648
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 734 Post(s)
Liked 561 Times in 423 Posts
I have a 750w BBS02 even more severely limited with a 30 chainring and top speed of 18 mph or so on flat terrain. However, in socal, electric bikes are prohibited off road except where motor vehicles are allowed. It's a moot point however since there is policing in only a couple of easily avoided areas. Probably, you'll encounter the same situation; nobody is going to know or care that your bike is restricted.
2old is offline  
Likes For 2old:
Old 07-23-22, 09:35 AM
  #3  
bikebikebike
Senior Member
 
Join Date: Jul 2006
Location: TX
Posts: 504

Bikes: Downtube IX NS&FS, Dahon Speed8Pro/Matrix/Curve, Brom S2L,Montague Para, ICE-XL w/Rollie/Schlumpf, Trident Spike, ebikes, BFSatRDay

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Liked 91 Times in 77 Posts
Yes
a law is only as good as its implementation.
So is character and honor.
It's why we are having issues
bikebikebike is offline  
Old 07-28-22, 07:02 PM
  #4  
KPREN
Full Member
 
Join Date: Feb 2021
Location: Wadsworth, Ohio
Posts: 343

Bikes: 2008 S Works Stumpjumper FSR Carbon, 2016 E Fat Titanium Bike Custom built by me.

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 121 Post(s)
Liked 178 Times in 106 Posts
Originally Posted by eric1514 View Post
Hi all,

I'm thinking about converting a Trek Marlin 5 into an ebike with a 750w Bafang mid drive motor. I will use this bike mostly around town but I want to take it camping and ride some easy trails with it, also. I'm assuming I can, with programming, limit the top speed to 20mph. Would doing this then make this a Class 2 ebike and therefore legal on State and National Park trails?

TIA,
Eric
For mountain biking you will want to reprogram the mid drive as the factory setting are appropriate for Chinese commuting, not mountain biking.
The first setting is about 40% power and will stuff you right in a tree. I have my first 7 levels programed as class 1 and the remaining two class 3. I am seldom in class three and never ran class 3 on mountain bike trails. Just remember, big dogs can run almost 30 mph and you will curse yourself for limiting top speed to 20 mph when trying to beat a storm.
KPREN is offline  
Likes For KPREN:
Old 07-29-22, 04:38 AM
  #5  
eric1514
Newbie
Thread Starter
 
Join Date: May 2007
Location: Boise, ID
Posts: 55

Bikes: 1968 Raleigh SuperCourse, 2016 Trek Marlin 5

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Likes: 0
Liked 2 Times in 1 Post
Originally Posted by KPREN View Post
For mountain biking you will want to reprogram the mid drive as the factory setting are appropriate for Chinese commuting, not mountain biking.
The first setting is about 40% power and will stuff you right in a tree. I have my first 7 levels programed as class 1 and the remaining two class 3. I am seldom in class three and never ran class 3 on mountain bike trails. Just remember, big dogs can run almost 30 mph and you will curse yourself for limiting top speed to 20 mph when trying to beat a storm.
I assume you're talking about reprogramming with software and a USB cable connecting my computer to the motor.
eric1514 is offline  
Old 07-30-22, 05:26 PM
  #6  
KPREN
Full Member
 
Join Date: Feb 2021
Location: Wadsworth, Ohio
Posts: 343

Bikes: 2008 S Works Stumpjumper FSR Carbon, 2016 E Fat Titanium Bike Custom built by me.

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 121 Post(s)
Liked 178 Times in 106 Posts
Originally Posted by eric1514 View Post
I assume you're talking about reprogramming with software and a USB cable connecting my computer to the motor.
yes
KPREN is offline  
Old 09-05-22, 09:18 PM
  #7  
bikebikebike
Senior Member
 
Join Date: Jul 2006
Location: TX
Posts: 504

Bikes: Downtube IX NS&FS, Dahon Speed8Pro/Matrix/Curve, Brom S2L,Montague Para, ICE-XL w/Rollie/Schlumpf, Trident Spike, ebikes, BFSatRDay

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Liked 91 Times in 77 Posts
@KPEN, Not trying to provoke , but I seldom see folks "trying to beat a storm", mostly just clowning.
That's the case for speed limiting cars as a safety measure, as well.
Yeah, it's gonna keep you from beating out the T-Rex in your rearview mirror, but the aggregate safety is increased.
Biking is about respecting the slower moving , cars vs bikes and pedestrians, and biasing towards the slower for a true net safety gain.
I am personally biased towards controlability and low speed assists in ebikes, but that starts debates that prevents compromises needed for integration.
Self control cannot be assumed in a lot of situations.
bikebikebike is offline  
Old 09-06-22, 08:22 PM
  #8  
KPREN
Full Member
 
Join Date: Feb 2021
Location: Wadsworth, Ohio
Posts: 343

Bikes: 2008 S Works Stumpjumper FSR Carbon, 2016 E Fat Titanium Bike Custom built by me.

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 121 Post(s)
Liked 178 Times in 106 Posts
Originally Posted by bikebikebike View Post
@KPEN, Not trying to provoke , but I seldom see folks "trying to beat a storm", mostly just clowning.
That's the case for speed limiting cars as a safety measure, as well.
Yeah, it's gonna keep you from beating out the T-Rex in your rearview mirror, but the aggregate safety is increased.
Biking is about respecting the slower moving , cars vs bikes and pedestrians, and biasing towards the slower for a true net safety gain.
I am personally biased towards controlability and low speed assists in ebikes, but that starts debates that prevents compromises needed for integration.
Self control cannot be assumed in a lot of situations.
I take it that you have not toured with an e bike.
KPREN is offline  
Old 09-15-22, 03:59 PM
  #9  
bikebikebike
Senior Member
 
Join Date: Jul 2006
Location: TX
Posts: 504

Bikes: Downtube IX NS&FS, Dahon Speed8Pro/Matrix/Curve, Brom S2L,Montague Para, ICE-XL w/Rollie/Schlumpf, Trident Spike, ebikes, BFSatRDay

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Liked 91 Times in 77 Posts
Given the vast numbers of ebike tourers, I can see that they should be the foundation of transportation strategy.
Realize in the 20's there was a strong movement for cars to be speed governed to 20 mph.
bikebikebike is offline  
Old 09-17-22, 11:03 PM
  #10  
Leisesturm
Senior Member
 
Join Date: Jul 2005
Posts: 5,263
Mentioned: 24 Post(s)
Tagged: 0 Thread(s)
Quoted: 2004 Post(s)
Liked 450 Times in 326 Posts
Originally Posted by bikebikebike View Post
Given the vast numbers of ebike tourers, I can see that they should be the foundation of transportation strategy.
Realize in the 20's there was a strong movement for cars to be speed governed to 20 mph.
And where, exactly, did they get with that? All this is is just thinly veiled virtue signaling. There is no gun to any riders head forcing them to ride faster than 20mph because their motor is capable of more. If the o.p. really wanted to "be trail compliant" they would not be buying a 750W motor to try and restrict in a mid-drive configuration. All but impossible. The mid-drive has no control over the run out or the braking of a bike, all it can do is stop assisting once 20mph (or 28mph) is reached. Unless I way miss my guess, the Bafang is already set to do that out of the box.

It is only when you want to derestrict the motor (go faster illegally) that you have to get the computer and a serial cable out. Not so with a car. If they ever were to restrict cars to such and such a speed it would be easy to do, the Penske moving truck I rented once was speed limited to 75mph and by gum, so it was. Going down a mountainside with a two bedroom apartment worth of possessions and a four door sedan on a trailer and it did not go a single mph above the set limit no matter what. If y'all keep witching about it they may finally do the work necessary, and your e-bikes WILL be speed governed to 20mph period, end of story. When the pearl clutchers realize 20mph is actually pretty damn fast and very few people actually ride that fast all the time, you'll either ask for the limit to be even lower, or for e-bikes to be banned outright. I'm good with that. As long as there is an exception for Cargo and Utility bikes (and there will be) knock yourselves out. So, TL;DR ... when threads asking "how can I restrict my motor to be compliant" come up. The answer is: 'it already is restricted'. Unless you bought an illegal motor (and who would do that) it will already come Class 2. And if you know enough to ask the question, then you already know that.
Leisesturm is offline  
Old 09-19-22, 09:22 PM
  #11  
bikebikebike
Senior Member
 
Join Date: Jul 2006
Location: TX
Posts: 504

Bikes: Downtube IX NS&FS, Dahon Speed8Pro/Matrix/Curve, Brom S2L,Montague Para, ICE-XL w/Rollie/Schlumpf, Trident Spike, ebikes, BFSatRDay

Mentioned: 2 Post(s)
Tagged: 0 Thread(s)
Quoted: 168 Post(s)
Liked 91 Times in 77 Posts
It's not about virtue signaling. it's about good design.
Is it fun to go fast? duh.
Speed and safety are part of a complex algorithm, and there is a place on the curve that optimizes priorities.
Working together is one of those priorities.
Speed and safety tend be inversely related. Can you go, "what about being chased by tiger?" sure.
European standards tend to have speed max out at a reasonable 16 miles an hour. 20 kpm.
Can I pedal faster than that? Duh
We have a pretty poor governance of our transportation infrastructure. Unregulated speed is a part of that.
The answer is not "no governance", The answer is probably more along the lines of enforceable regulation.
And buy in by all the participants. It's a team sport.

Police where I am have all but stopped traffic enforcement.
Not surprisingly 10-15% drive like total jerks. Why not?
Injury accidents are reflecting that. Speed regulation is just part of the fix.

Last edited by bikebikebike; 09-19-22 at 09:27 PM.
bikebikebike is offline  
Old 09-21-22, 06:46 AM
  #12  
unterhausen
Randomhead
 
Join Date: Aug 2008
Location: Happy Valley, Pennsylvania
Posts: 22,971
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 4 Post(s)
Liked 2,545 Times in 1,785 Posts
I'm pretty sure you have to de-restrict a bafang to go more than 20 unless the vendor has de-restricted it for you. But you usually have to ask.
unterhausen is offline  
Old 09-21-22, 09:36 AM
  #13  
2old
Senior Member
 
Join Date: Jul 2014
Location: socal
Posts: 3,648
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 734 Post(s)
Liked 561 Times in 423 Posts
I think the BBS01 & 2 are basically the same with different controllers, so if it were critical, the "02" controller could be replaced with an "01".
2old is offline  
Old 09-24-22, 07:01 PM
  #14  
randomgear
Senior Member
 
Join Date: Jul 2006
Location: beantown
Posts: 942

Bikes: '89 Specialized Hardrock Fixed Gear Commuter; 1984? Dawes Atlantis

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 43 Post(s)
Liked 2 Times in 1 Post
Originally Posted by unterhausen View Post
I'm pretty sure you have to de-restrict a bafang to go more than 20 unless the vendor has de-restricted it for you. But you usually have to ask.
The Bafang 750 watt mid-drive I bought in August can do 28mph when riding singlespeed (44x17) using the throttle (simply can't pedal that fast in such gear). Haven't yet played with it enough with a derailer to find out if it increases with better gearing. Assuming it uses wheel RPM to calculate speed, it may not.
randomgear is offline  
Old 09-25-22, 09:23 AM
  #15  
2old
Senior Member
 
Join Date: Jul 2014
Location: socal
Posts: 3,648
Mentioned: 8 Post(s)
Tagged: 0 Thread(s)
Quoted: 734 Post(s)
Liked 561 Times in 423 Posts
I was riding at 30 mph (50 kph) with 46:11 (AIR) before i basically restricted it to 20 or so with a 36:14 high gear. Probably it could have gone faster than 30, but that had the engine spinning fast enough for me.
2old is offline  
Likes For 2old:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright © 2022 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.