skyungjae
10 kW
Hey y'all,
I'm starting a thread on my Sur-Ron Light Bee to give other SR owners and prospective owners an easier place to find my modifications, thoughts, and experiences owning this bike.
First off, I'm located in the United States. Luna is the only authorized distributor and only offered one model back when I purchased the bike in August 2018. There was no X version and still no street legal version available (with appropriate lighting and documentation to be registered with the DMV).
Freshly assembled.

Anyhow, ERT reached out to me back in December 2018 to see if I could assist in developing a plug and play ASI BAC 4000 for the SR. I was reluctant at first since I rode the bike often and didn't want to spend any time away from it, but the stars aligned and I had a business trip which would give me time to loan the bike.
When I returned from my trip, I felt like I had an all new machine.

ERT wanted me to ride it for a while to see if I ran into any issues. With the factory battery, the top speed increased from 42mph to 47mph. Acceleration was much smoother, and the bike sounded a lot better. The big game changer was the variable regen which was set up as a reverse direction throttle on the left side. Variable regen is the reason I've only had to change brake pads once on this bike over the 3000ish miles I've put on it. The regen has taken over about 90% of braking duties. It's strong enough to take me to a complete stop and even lock up the rear wheel. At this point, I pretty much only use the brakes to turn on the brake light.
I returned the bike in February 2019 to finalize the designs in the harness and mounting hardware. This gave ERT time to dabble in getting more power out of this thing. Now they offer a drop-in 72V battery as well as a plug and play 20S LiPO harness with a bluetooth BMS.
The main difference I could visually tell about the new set up was the harness went from JST type connectors to the HiGo (Bafang) style. The controller has a mounting bracket and the orientation has been flipped 180 degrees (plugs facing out on bottom instead of on top). The controller can be mounted with the wires facing inward, but it does put stress on the wires and plugs. It's recommended orange side out.
More info and videos are available here:
https://electricrt.com/sur-ron-upgrades/
https://electricrt.com/battery/

***custom 20S battery assembled from 5S 8000mAh Zippy packs***
As for my bike as a whole, it's come a long way since August 2018.

In order from most recent:
Headlights and brackets:

https://www.amazon.com/gp/product/B07484L86P
https://www.amazon.com/gp/product/B00RE4HTPY
The beam pattern is very narrow, and a switch is needed to cycle through the modes. The brackets are best mounted with the hinge on the outside. If not, the steel hinge will hit the welds on the frame when turning the bars all the way to either side. They protrude out further than the rubber fork bumpers.
Tires & tube:
Front Shinko: https://www.amazon.com/gp/product/B001PS2QQC
Rear Duro: https://www.amazon.com/gp/product/B011J6TK1S
Tube for the rear: https://www.amazon.com/gp/product/B01CQ0ABAK
I reused the tube for the front tire. The rear has a lot of clearance. I had to re-set the bead on the front tire to get it to stop rubbing. There are square blocks along the inside of the tire which help with alignment.
Affordable replacement chain:
https://www.amazon.com/gp/product/B0022ZJ2WI
Foot pegs:
https://www.amazon.com/gp/product/B07BF7S7QK
The small pins will disappear, so it's best to back them out and drop some thread locker on each.
Reflective rim tape:
https://www.amazon.com/gp/product/B002VY4IWE
It's easier to just apply the tape by hand rather than try to figure out how to use the applicator.
Finned brake pads:

https://www.amazon.com/gp/product/B07CZSM719
I had to clip off the fins on one side for them to fit the caliper properly.
Rear Brake lights:

https://www.amazon.com/Purishion-Universal-Flexible-Integrated-Motorcycle/dp/B01L8YZ0II
https://www.amazon.com/gp/product/B077NCT36C
Using the existing brake sensors, I decided to re-purpose them into brake lights. These lights in particular will fry the fragile brake reed sensors, which is why I used a standard relay. There are other lights with less LEDs where the reed sensors can handle the load, but I didn't think any were bright enough.
I also have a flashing module with a g-sensor which is no longer in production. This is what they're selling now: https://www.amazon.com/dp/B00SQEI4GO
Mirror (left side):
https://www.amazon.com/gp/product/B0009R96YK
Fenders:
Front https://www.amazon.com/gp/product/B01NBB4EWY
Rear https://www.amazon.com/Mucky-Nutz-Face-Fender-Reflective/dp/B01N0HE7FA
I had to replace the front with an old Marzocchi fender because the Shinko tires would rub on the Mucky Nutz. To install the rear, I had to make additional holes using a hot flat tip screw driver.
Other things people may have questions about. I did register this bike as a moped in California. Eco Mode on the factory SR does comply with the power and speed requirements in California; however, the bike is missing stop lights, mirror, and reflectors to be fully compliant.
For those of you California folks, here's the link for the registration: I think the fee now is $23, but you can call the DMV to verify.
https://www.dmv.ca.gov/portal/dmv/?1dmy&urile=wcm:path:/dmv_content_en/dmv/forms/reg/reg230
When my SR is powered on, it defaults to low power which falls under the power and speed requirement to lawfully ride on the streets. The ASI unit has 3 different power profiles using the Assist settings through the display which is great for conserving power among potential legality issues.
Why didn't I go with an X controller or X bike? Neither were available at the time of purchase. When the X controller became available, the regen was passive and only worked in sport mode when coasting. The cost of the X controller isn't bad with the core swap, but the improvements weren't worth the time I'd be spending in my garage installing it. The later iterations of the X controller got rid of regen altogether. To me, it just makes much more sense to have variable regen that takes over for the majority of my braking.
Why didn't I buy a supermoto wheel set? I ask myself that every day. I regret not buying a set when they were on sale for $319. I'm very satisfied with my current dual sport tires, but I'll always be curious how much better the street riding would be with a legitimate set of street tires.
As for my battery set up, I don't recommend going the same path I took:

:lol: :lol: :lol:
A lot of that wiring could have been eliminated, but I wanted to keep things modular.
Well, that's it for now. I will continue to post updates and answer questions here as my SR continues to evolve.
I'm starting a thread on my Sur-Ron Light Bee to give other SR owners and prospective owners an easier place to find my modifications, thoughts, and experiences owning this bike.
First off, I'm located in the United States. Luna is the only authorized distributor and only offered one model back when I purchased the bike in August 2018. There was no X version and still no street legal version available (with appropriate lighting and documentation to be registered with the DMV).
Freshly assembled.

Anyhow, ERT reached out to me back in December 2018 to see if I could assist in developing a plug and play ASI BAC 4000 for the SR. I was reluctant at first since I rode the bike often and didn't want to spend any time away from it, but the stars aligned and I had a business trip which would give me time to loan the bike.
When I returned from my trip, I felt like I had an all new machine.

ERT wanted me to ride it for a while to see if I ran into any issues. With the factory battery, the top speed increased from 42mph to 47mph. Acceleration was much smoother, and the bike sounded a lot better. The big game changer was the variable regen which was set up as a reverse direction throttle on the left side. Variable regen is the reason I've only had to change brake pads once on this bike over the 3000ish miles I've put on it. The regen has taken over about 90% of braking duties. It's strong enough to take me to a complete stop and even lock up the rear wheel. At this point, I pretty much only use the brakes to turn on the brake light.
I returned the bike in February 2019 to finalize the designs in the harness and mounting hardware. This gave ERT time to dabble in getting more power out of this thing. Now they offer a drop-in 72V battery as well as a plug and play 20S LiPO harness with a bluetooth BMS.
The main difference I could visually tell about the new set up was the harness went from JST type connectors to the HiGo (Bafang) style. The controller has a mounting bracket and the orientation has been flipped 180 degrees (plugs facing out on bottom instead of on top). The controller can be mounted with the wires facing inward, but it does put stress on the wires and plugs. It's recommended orange side out.
More info and videos are available here:
https://electricrt.com/sur-ron-upgrades/
https://electricrt.com/battery/

***custom 20S battery assembled from 5S 8000mAh Zippy packs***
As for my bike as a whole, it's come a long way since August 2018.

In order from most recent:
Headlights and brackets:

https://www.amazon.com/gp/product/B07484L86P
https://www.amazon.com/gp/product/B00RE4HTPY
The beam pattern is very narrow, and a switch is needed to cycle through the modes. The brackets are best mounted with the hinge on the outside. If not, the steel hinge will hit the welds on the frame when turning the bars all the way to either side. They protrude out further than the rubber fork bumpers.
Tires & tube:
Front Shinko: https://www.amazon.com/gp/product/B001PS2QQC
Rear Duro: https://www.amazon.com/gp/product/B011J6TK1S
Tube for the rear: https://www.amazon.com/gp/product/B01CQ0ABAK
I reused the tube for the front tire. The rear has a lot of clearance. I had to re-set the bead on the front tire to get it to stop rubbing. There are square blocks along the inside of the tire which help with alignment.
Affordable replacement chain:
https://www.amazon.com/gp/product/B0022ZJ2WI
Foot pegs:
https://www.amazon.com/gp/product/B07BF7S7QK
The small pins will disappear, so it's best to back them out and drop some thread locker on each.
Reflective rim tape:
https://www.amazon.com/gp/product/B002VY4IWE
It's easier to just apply the tape by hand rather than try to figure out how to use the applicator.
Finned brake pads:

https://www.amazon.com/gp/product/B07CZSM719
I had to clip off the fins on one side for them to fit the caliper properly.
Rear Brake lights:

https://www.amazon.com/Purishion-Universal-Flexible-Integrated-Motorcycle/dp/B01L8YZ0II
https://www.amazon.com/gp/product/B077NCT36C
Using the existing brake sensors, I decided to re-purpose them into brake lights. These lights in particular will fry the fragile brake reed sensors, which is why I used a standard relay. There are other lights with less LEDs where the reed sensors can handle the load, but I didn't think any were bright enough.
I also have a flashing module with a g-sensor which is no longer in production. This is what they're selling now: https://www.amazon.com/dp/B00SQEI4GO
Mirror (left side):
https://www.amazon.com/gp/product/B0009R96YK
Fenders:
Front https://www.amazon.com/gp/product/B01NBB4EWY
Rear https://www.amazon.com/Mucky-Nutz-Face-Fender-Reflective/dp/B01N0HE7FA
I had to replace the front with an old Marzocchi fender because the Shinko tires would rub on the Mucky Nutz. To install the rear, I had to make additional holes using a hot flat tip screw driver.
Other things people may have questions about. I did register this bike as a moped in California. Eco Mode on the factory SR does comply with the power and speed requirements in California; however, the bike is missing stop lights, mirror, and reflectors to be fully compliant.
For those of you California folks, here's the link for the registration: I think the fee now is $23, but you can call the DMV to verify.
https://www.dmv.ca.gov/portal/dmv/?1dmy&urile=wcm:path:/dmv_content_en/dmv/forms/reg/reg230
From the California vehicle code:
24015. (a) Motorized bicycles shall comply with those federal motor vehicle safety standards established under the National Traffic and Motor Vehicle Safety Act of 1966 (15 U.S.C., Sec. 1381, et seq.) which are applicable to a motor-driven cycle, as that term is defined in such federal standards. Such standards include, but are not limited to, provisions requiring a headlamp, taillamp, stoplamp, side and rear reflex reflectors, and adequate brakes.
(b) In addition to equipment required in subdivision (a), all motorized bicycles operated upon a highway shall be equipped with a mirror as required in subdivision (a) of Section 26709, a horn as required in Section 27000, and an adequate muffler as required in subdivision (a) of Section 27150.
From CHP form 888:
Motorized Bicycle: Compliance with Federal Safety Standards (24015). Motorized bicycles shall comply with those federal motor vehicle safety standards established under the National Traffic and Motor Vehicle Safety Act of 1966 which are applicable to a motor-driven cycle, as that term is defined in such federal standards. Such standards include, but are not limited to, provisions requiring a headlamp, taillamp, stoplamp, side and rear reflectors, and adequate brakes. In addition, all motorized bicycles operated upon a highway shall be equipped with a mirror, a horn, and an adequate muffler as required by the Vehicle Code.
When my SR is powered on, it defaults to low power which falls under the power and speed requirement to lawfully ride on the streets. The ASI unit has 3 different power profiles using the Assist settings through the display which is great for conserving power among potential legality issues.
Why didn't I go with an X controller or X bike? Neither were available at the time of purchase. When the X controller became available, the regen was passive and only worked in sport mode when coasting. The cost of the X controller isn't bad with the core swap, but the improvements weren't worth the time I'd be spending in my garage installing it. The later iterations of the X controller got rid of regen altogether. To me, it just makes much more sense to have variable regen that takes over for the majority of my braking.
Why didn't I buy a supermoto wheel set? I ask myself that every day. I regret not buying a set when they were on sale for $319. I'm very satisfied with my current dual sport tires, but I'll always be curious how much better the street riding would be with a legitimate set of street tires.
As for my battery set up, I don't recommend going the same path I took:

:lol: :lol: :lol:
A lot of that wiring could have been eliminated, but I wanted to keep things modular.
Well, that's it for now. I will continue to post updates and answer questions here as my SR continues to evolve.