Sur-Ron - New Mid drive Bike

General Discussion about large electric scooters and motorcycles and other things with no pedals.
captnshrms   100 µW

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Re: Sur-Ron - New Mid drive Bike

Post by captnshrms » Feb 08 2019 6:37pm

fechter wrote:
Feb 08 2019 9:05am

Sorry, unlikely I would have time to make another one. I'm struggling to finish the first one. It has not be tested yet. Once I get it finished and tested, I'll post construction pics. My design is based largely on what I had available in my junk pile and could be improved upon quite a bit.

Partially welded half pack:

Img_1034A.jpg
Cool, I look forward to seeing them.

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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Feb 09 2019 2:25pm

3DTOPO wrote:
Feb 07 2019 8:13pm
Offroader wrote:
Feb 07 2019 8:09pm
Why can't anyone figure out how to do a shunt mod on the controller? Is there not a shunt?
Search the thread for Shunt. Search = Powerful :D

It sounds like it has been done, but questions abound if the BMS is up to it.
I have been following this thread for quite a while, nobody has ever done a shunt mod. Someone from Russia took some pictures with the controller cleaned and de-potted it, but I have never seen anyone point out where the shunt is exactly or actually say they did a shunt mod.

Maybe I missed something but I can't find anything.

BMS is no big deal because it can be replaced and I believe the current limit is the external 100 amp circuit breaker?? I'm not sure if the BMS has a 100 amp current limit on it but wouldn't this also be easily modded because it would probably have a shunt also?

baja ho   100 µW

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Re: Sur-Ron - New Mid drive Bike

Post by baja ho » Feb 12 2019 11:30pm

Flopped my Sur-ron over the other day and broke the brake lever off for the rear brake. Well contacted Luna to get a new lever, well they don't sell the lever as it has a pressed in pin at the pivot (also took it to a bike shop to fix it, a no go) so you need to buy a complete unit, a master to caliper with the brake line & fluid installed, ready to go. Problem 1#, Luna will only sell you both front & rear brake sets complete at $176.00 and will not separate the two, leaving you with a set that you don't need and this is to replace a lever that should not cost more than $15.00, has anyone run into this? Problem 2# In order to replace the rear brake set complete you need to remove the motor ( No FU*%#NG way), well back to the bike shop and had them just remove the master and bleed the system, and mind you this is just for a broken lever that I should have been able to replace myself for not much more then about fifteen bucks, has anyone had this experience? Call me FRUSTRATED !!

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Feb 14 2019 1:35am

baja ho wrote:
Feb 12 2019 11:30pm
Flopped my Sur-ron over the other day and broke the brake lever off for the rear brake. Well contacted Luna to get a new lever, well they don't sell the lever as it has a pressed in pin at the pivot (also took it to a bike shop to fix it, a no go) so you need to buy a complete unit, a master to caliper with the brake line & fluid installed, ready to go. Problem 1#, Luna will only sell you both front & rear brake sets complete at $176.00 and will not separate the two, leaving you with a set that you don't need and this is to replace a lever that should not cost more than $15.00, has anyone run into this? Problem 2# In order to replace the rear brake set complete you need to remove the motor ( No FU*%#NG way), well back to the bike shop and had them just remove the master and bleed the system, and mind you this is just for a broken lever that I should have been able to replace myself for not much more then about fifteen bucks, has anyone had this experience? Call me FRUSTRATED !!
The cheapest route is to get a Shimano lever assembly for one side. As cheap as $25. A bike shop will swap levers and bleed for about $30 labor.

crazy_dave   10 mW

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Re: Sur-Ron - New Mid drive Bike

Post by crazy_dave » Feb 14 2019 12:03pm

^^^This^^^ and you could save the labor cost by getting a lager plastic or glass syringe and some proper fitting tube and back bleed (from the caliper to the master cylinder) the lines. Much easier to get the air out.
It’s better to apologize than it is to ask permission.

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BCTECH   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by BCTECH » Feb 14 2019 12:58pm

is the rear brake line running through the bike all internally? can you replace the whole rear brake without re bleed?

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Feb 19 2019 6:15am

If you needed a 2nd charger to charge sometimes while at work, what would be the best cost effective way to go about this? Just looking for some thoughts on what you guys would do for a 2nd charger,

Or would you just buy a 2nd sur-ron charger. I'm kind of leaning towards not doing that because I will probably eventually upgrade the battery down the road.

Thanks

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Feb 19 2019 6:43am

simply aliexpress....2-3-4A and around 20-40$

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derb   10 mW

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Re: Sur-Ron - New Mid drive Bike

Post by derb » Feb 19 2019 1:05pm


Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Feb 20 2019 1:43pm

Does a charger exist that can run directly off my van's 12v system? It seems using an inverter and then the stock charger is wasting a bunch of electricity (turned to heat) going from DC to AC and then back. I'm envisioning something that can be clipped to the battery terminals and plugged into the Sur-ron's battery.

My van has 2 batteries and will be hooked up to 2 or 3 100w solar panels at the time.

Fizzer   1 µW

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Re: Sur-Ron - New Mid drive Bike

Post by Fizzer » Feb 20 2019 6:52pm

Joined the Sur-ron community yesterday. Completely satisfied! Thanks to everyone posting on this forum. Was very educational.

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Feb 21 2019 11:59am

Lelandjt wrote:
Feb 20 2019 1:43pm
Does a charger exist that can run directly off my van's 12v system? It seems using an inverter and then the stock charger is wasting a bunch of electricity (turned to heat) going from DC to AC and then back. I'm envisioning something that can be clipped to the battery terminals and plugged into the Sur-ron's battery.
This one would be pretty close:
https://www.ebay.com/itm/900W-DC-DC-Boo ... :rk:6:pf:0
900W DC-DC Boost Converter 8-60V To 10-120V 15A Step Up Power Supply Module US
✔Digital Control + LED Display✔US Stock✔8V-60V input
boost converter.jpg
boost converter.jpg (96.91 KiB) Viewed 4190 times
There are others out there with similar features. Keep in mind the input is limited to 20A regardless of voltage, so you could only expect about 240W with a 12v supply.

A big inverter and the stock charger are not a bad way to go. The losses would more than the single stage dc-dc converter shown but not terrible.
"One test is worth a thousand opinions"

Rabid   1 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Rabid » Feb 22 2019 9:08am

Has anyone got plans for a decent bash guard? I saw some somewhere, but can't seem to find them again.

I have seen Luna's ready-made solution, but then read they don't last any better that the originals... Thanks ☺

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Feb 22 2019 12:46pm

fechter wrote:
Feb 21 2019 11:59am
Lelandjt wrote:
Feb 20 2019 1:43pm
Does a charger exist that can run directly off my van's 12v system? It seems using an inverter and then the stock charger is wasting a bunch of electricity (turned to heat) going from DC to AC and then back. I'm envisioning something that can be clipped to the battery terminals and plugged into the Sur-ron's battery.
This one would be pretty close:
https://www.ebay.com/itm/900W-DC-DC-Boo ... :rk:6:pf:0
900W DC-DC Boost Converter 8-60V To 10-120V 15A Step Up Power Supply Module US
✔Digital Control + LED Display✔US Stock✔8V-60V input
boost converter.jpg

There are others out there with similar features. Keep in mind the input is limited to 20A regardless of voltage, so you could only expect about 240W with a 12v supply.

A big inverter and the stock charger are not a bad way to go. The losses would more than the single stage dc-dc converter shown but not terrible.
I guess the important question is how much loss is there (as heat?) running an inverter and the stock charger. That's clearly the simple way to do it but I figured efficiency mattered when I've only got a couple solar panels or running my van's engine to make the electricity.

SlowCo   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by SlowCo » Feb 22 2019 1:09pm

Lelandjt wrote:
Feb 22 2019 12:46pm
...running my van's engine to make the electricity.
Wouldn't a small generator and the original charger be more efficient then running your van's engine to charge the 12V batteries to then use an inverter or voltage booster to charge your Sur Ron bike's battery? And the small generator could be used for different things in the van/camping and around the house (back up) as well.
Last edited by SlowCo on Feb 23 2019 4:11am, edited 1 time in total.

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efMX Trials Electric Freeride   1 MW

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Re: Sur-Ron - New Mid drive Bike

Post by efMX Trials Electric Freeride » Feb 22 2019 10:56pm

Rabid wrote:
Feb 22 2019 9:08am
Has anyone got plans for a decent bash guard? I saw some somewhere, but can't seem to find them again.

I have seen Luna's ready-made solution, but then read they don't last any better that the originals... Thanks ☺
contact Aebikes, they had some nice stainless bash plates made for surron with reinforcement in critical areas.. aebikes.com.au
some ride & sk8 videos:
metacafe.com/channels/NATAS666DAMIEN
http://www.youtube.com/natas666damien
i have nothing for sale.. :)

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Feb 23 2019 1:14pm

SlowCo wrote:
Feb 22 2019 1:09pm
Lelandjt wrote:
Feb 22 2019 12:46pm
...running my van's engine to make the electricity.
Wouldn't a small generator and the original charger be more efficient then running your van's engine to charge the 12V batteries to then use an inverter or voltage booster to charge your Sur Ron bike's battery? And the small generator could be used for different things in the van/camping and around the house (back up) as well.
I wouldn't run my van's engine when parked to charge the batteries, only when driving. When parked and charging there will be solar panels sending electricity into the van's dual heavy duty batteries.

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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Feb 24 2019 8:29am

What I plan to do with a 2nd charger since I will rarely use it, is use some power supplies I have at my home already.

I'll use the programmable Eaton APR48-3G which I have sitting around unused, which can be adjusted for both current and voltage as it is a CC power supply.

viewtopic.php?f=2&t=66169

And I will use a Dell 12 volt server power supply (rated up to like 40 amps) I also have laying around and put it in series with with the Eaton APR48-3G.

So it will be 12 volt + 55 volt = 67 volt. I'll limit current and adjust voltage with the APR48-3G.

If anyone sees any issues with doing this please let me know. Thank you

Rabid   1 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Rabid » Feb 25 2019 9:04am

efMX Trials Electric Freeride wrote:
Feb 22 2019 10:56pm
Rabid wrote:
Feb 22 2019 9:08am
Has anyone got plans for a decent bash guard? I saw some somewhere, but can't seem to find them again.

I have seen Luna's ready-made solution, but then read they don't last any better that the originals... Thanks ☺
contact Aebikes, they had some nice stainless bash plates made for surron with reinforcement in critical areas.. aebikes.com.au
Thanks ☺ I'll check it out!

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Re: Sur-Ron - New Mid drive Bike

Post by Jasonvh » Feb 25 2019 11:21am

Based on the discussion here I bought two Sur Ron bikes! One Green with standard controller and one grey with the X controller. I figure I’d need a spare because friends and family need to experience this too. It’s a different kind of riding. I’ve loved my mountain bike and my dirtbike equally. Just can’t ride the dirtbike anywhere around civilization it seems.

Already started on the upgrades.

Just ordered a Fox 40 fork and a Fox DHX2 shock.

Installed a Diety 80mm rise bar and Diety Intake stem.

Installed a 26” wheel on one bike. Its a Chris King hub Laced to a Mavic 321 rim with 14/17 gauge DT Revolution spokes and alloy nipples. I’m testing the limits of the spokes for sure. The hub and rim should hold up with all the compliance of the spokes. I’ve been a wheel builder for quite a while but this is new territory. The wheel made a huge difference in weight. The front end is way lighter. However, the added height makes steering a bit slow for tight trails. Probably need more preload on the rear to push the bike forward.
C1591172-3D6F-4462-9A1B-D6EBF8603862.jpeg
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181B2F4F-1516-4108-8F5A-06A78753FF18.jpeg
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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Feb 25 2019 4:28pm

Should have used a 24" on the front since the rear suspension is not adjustable to raise the rear.


What 26" tire and size are you using?

I like how you used the thin spokes as 12 gauge is way too thick and unnecesary for the front. I use 14/15 gauge for the front of my other ebike for years without a single issue or loose spokes. 17 gauge is kind if thin but will probably work.

Since you have both versions of the bike are there any noticable differences in power between the versions?

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Re: Sur-Ron - New Mid drive Bike

Post by Jasonvh » Feb 25 2019 6:26pm

Offroader wrote:
Feb 25 2019 4:28pm
Should have used a 24" on the front since the rear suspension is not adjustable to raise the rear.


What 26" tire and size are you using?

I like how you used the thin spokes as 12 gauge is way too thick and unnecesary for the front. I use 14/15 gauge for the front of my other ebike for years without a single issue or loose spokes. 17 gauge is kind if thin but will probably work.

Since you have both versions of the bike are there any noticable differences in power between the versions?

Yeah, the 17 gauge spokes are just what I have on hand. Also the case with the rim. Being a very heavy DH rim allows me to get away with such thin spokes on a bicycle. A point load deflection is spread over more spokes. This wheel is not optimal for the Sur Ron. I want to understand how changes in wheel size affect the handling of this bike. A change like this on my mountain bike or dirtbike would render them unreadable. The Sur Ron is still fun with this circus hoop on there. However, the steering is now too slow.

I was looking at building new wheels soon. I’d like to save some unsprung weight by useing 24” bicycle rims and trials tires. Im concerned with the durability being too low. Rider skill can be a major factor here too. Or, stick with proven motorcycle hoops and rubber. Just build ‘em right. Proper gauge, tension,...

The tire is a Maxxis Minion DHR 2.8 with all the bells and whistles. Set up with a Stan’s tubeless kit. Great mountain bike tire (I usually run a DHF up front). Light, tough, super grip on most everything. Hell, I race endurance races with these and take em on lift access trails.

Differences...

I know I like the RST fork way more then the DNM 8. The DNM will twist in the crowns upon moderate torque. This has happened when pulling the bike around a very tight switchback. I kicked the bike up on the rear wheel, pivoted, then lowered the front wheel with some sideways momentum. The legs will stay in this twisted state until I loosen everthing up and realign the whole thing. I can’t torque the hardware enough to keep this twisting from happening. I’m up to 10 Nm on those silly little bolts. This kind of tension shouldn’t be nessesary. The DNM also feels heavy and dead. I feel Its harder to loft.

I put a 60t on the X. So direct comparison is tough. I’ll probably put 55t on both as that seems like a good balance. Just waiting on them to be available again.

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Feb 26 2019 2:45am

Jasonvh wrote:
Feb 25 2019 11:21am
Based on the discussion here I bought two Sur Ron bikes! One Green with standard controller and one grey with the X controller. I figure I’d need a spare because friends and family need to experience this too. It’s a different kind of riding. I’ve loved my mountain bike and my dirtbike equally. Just can’t ride the dirtbike anywhere around civilization it seems.

Already started on the upgrades.

Just ordered a Fox 40 fork and a Fox DHX2 shock.

Installed a Diety 80mm rise bar and Diety Intake stem.

Installed a 26” wheel on one bike. Its a Chris King hub Laced to a Mavic 321 rim with 14/17 gauge DT Revolution spokes and alloy nipples. I’m testing the limits of the spokes for sure. The hub and rim should hold up with all the compliance of the spokes. I’ve been a wheel builder for quite a while but this is new territory. The wheel made a huge difference in weight. The front end is way lighter. However, the added height makes steering a bit slow for tight trails. Probably need more preload on the rear to push the bike forward.

C1591172-3D6F-4462-9A1B-D6EBF8603862.jpeg

181B2F4F-1516-4108-8F5A-06A78753FF18.jpeg
With a 26" front wheel run the fork as low as you can. Also, get a 500lb spring (Rockshox Vivid spring for the stock shock). If you're over 200lbs get a 550. I have one to sell since I settled on the 500.
Move the rear axle as far back as the brake carrier allows and put the pegs in the rear position.

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Feb 26 2019 2:52am

Lelandjt wrote:
Feb 26 2019 2:45am
With a 26" front wheel run the fork as low as you can. Also, get a 500lb spring (Rockshox Vivid spring for the stock shock). If you're over 200lbs get a 550. I have one to sell since I settled on the 500.
Move the rear axle as far back as the brake carrier allows and put the pegs in the rear position.
Someone on here made a part that allowed the back wheel to go lower. Can't think of good keywords to find it though.

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Feb 26 2019 10:22am

Jasonvh wrote:
Feb 25 2019 11:21am
Based on the discussion here I bought two Sur Ron bikes! One Green with standard controller and one grey with the X controller.
It will be great to have some side-by-side comparisons. There seems to still be quite a bit of confusion about the exact differences.
"One test is worth a thousand opinions"

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