Sur Ron powertrain kit for DIY moto conversion?

General Discussion about large electric scooters and motorcycles and other things with no pedals.
Post Reply
81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 19 2018 3:48pm

Inspired by flat tire’s dirt bike conversion project and hoping to do the same some day, I am curious what the experts think of a “kit” like what is now being offered by Sur Ron: https://www.google.com/amp/s/evnerds.co ... anies/amp/

The power on the biggest motor setup seems like more than enough for a trail bike, and there are lighter options as well. Any trade offs to using a kit like this versus going the full DIY route of the two recent build threads on here? I am not an engineer and both flat tire and phate know waaaay more than I will ever know about all the compatibility issues.

I have a 250cc street legal dirt bike that weighs 226 lbs and puts out around 28hp. Would love to stay close to those numbers with a range of about 4 hours or so. Possible with one of the sur Ron powertrain kits?

User avatar
amberwolf   100 GW

100 GW
Posts: 24959
Joined: Aug 17 2009 6:43am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by amberwolf » Jun 19 2018 10:54pm

what kind of power usage do you expect?

if you typically use say, half that hp on average all the time thats about 10500w per hour, meaning 42000wh for a 4 hour range. A 42kwh pack is on the large and heavy side. :/

even 1/4 of that is a lot.

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 20 2018 1:12am

amberwolf wrote:
Jun 19 2018 10:54pm
what kind of power usage do you expect?

if you typically use say, half that hp on average all the time thats about 10500w per hour, meaning 42000wh for a 4 hour range. A 42kwh pack is on the large and heavy side. :/

even 1/4 of that is a lot.
Thanks for the reply, that is good info. So hard to judge power usage. I’d say most of the time, 1/4 of the bikes power is all that’s necessary for riding in the woods at my level. Honestly I would be totally open minded to usable power numbers, if the range could be reliable.

I need to do more research.

User avatar
amberwolf   100 GW

100 GW
Posts: 24959
Joined: Aug 17 2009 6:43am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by amberwolf » Jun 20 2018 2:31am

I don't have any idea how many wh/mile your usage scenario would require.

For my very heavy (few hundred pounds with me on it and typical cargo) and unaero trike, my typical commute at cruising of 20MPH and average around 15ish, takes between 45 and 60Wh/mile, on level ground.

Hauling a piano on the trailer at something like 10-12MPH or less took almost 60wh/mile too (probably double the weight of just the trike and me/etc).

There's some ebike / etc builds around here on the forum that get used for trails and stuff; maybe you can find power usage info in some of their threads. (will take poking around to find those threads, though; not sure how they are all titled).

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 20 2018 11:00am

Using thoroughbred’s estimate, it looks like around 1.45 kWh is an appropriate power need for the kind of riding I do.

I guess what I’m really wondering is what e-s members think of the power kits offered by sur-Ron as a diy option for converting motos. Havent seen it discussed much, but everyone seems to love the sur Ron bike.

User avatar
amberwolf   100 GW

100 GW
Posts: 24959
Joined: Aug 17 2009 6:43am
Location: Phoenix, AZ, USA, Earth, Sol, Local Bubble, Orion Arm, Milky Way, Local Group
Contact:

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by amberwolf » Jun 20 2018 11:59am

I can't help with the sur-ron stuff, but just figured you might want to consider power needs to feed it first, to be sure you could put all that on the one bike. :)

(sometimes it turns out a project isn't practical simply because of the amount/size/weight of the battery vs the carrying capacity of the rest of the project. :/ )

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 20 2018 12:01pm

Always appreciate your perspective, thank you :D

flat tire   10 kW

10 kW
Posts: 952
Joined: Feb 26 2014 12:20am

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by flat tire » Jun 20 2018 12:07pm

So can you actually buy that stuff? Where?

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 20 2018 12:23pm

flat tire wrote:
Jun 20 2018 12:07pm
So can you actually buy that stuff? Where?
I have no idea. The products appear on their website so they will probably be available soon: http://www.sur-ron.com/SDP180-?_l=en

I also don't see a price listed anywhere, but it seems like $2kish would be reasonable? Knowing what you know about your power needs and your current project, are any of the "powertrains" doable for your trail bike? If so, which one?

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 20 2018 12:58pm

Just sent an email to Sur-Ron's website, asking about availability and price. Maybe they will respond! :idea:

thoroughbred   100 mW

100 mW
Posts: 44
Joined: Apr 11 2018 6:18pm
Location: virginia

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by thoroughbred » Jun 20 2018 1:19pm

I'm no expert and nobody has checked my math so keep doing your own research. I think the light bee has a 2.2kWh battery and i don't know off hand how much singletrack time that buys you. It might be in the surron thread post from the australians. The 2.2kWh battery is $1500 from Luna

Your bike will be 100 # more than the light bee so that will have an effect on range, etc.

The surron offerings are 5, 8 and 16kW motors with 2 x kW burst capability. The luna folks are getting huge output from the 5kW motor in the light bee so I bet the 5 or 8 motors could work in a 200# dirtbike.

I'm in for a group buy if it should come to pass.

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 20 2018 2:15pm

thoroughbred wrote:
Jun 20 2018 1:19pm
I'm no expert and nobody has checked my math so keep doing your own research. I think the light bee has a 2.2kWh battery and i don't know off hand how much singletrack time that buys you. It might be in the surron thread post from the australians. The 2.2kWh battery is $1500 from Luna

Your bike will be 100 # more than the light bee so that will have an effect on range, etc.

The surron offerings are 5, 8 and 16kW motors with 2 x kW burst capability. The luna folks are getting huge output from the 5kW motor in the light bee so I bet the 5 or 8 motors could work in a 200# dirtbike.

I'm in for a group buy if it should come to pass.
Count me in for a group buy as well! The dual motor kit looks awesome...

Best of luck with your build, I’m subscribed 8)

Voltron   1 MW

1 MW
Posts: 1805
Joined: May 02 2013 4:53pm
Location: Santa Barbara CA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by Voltron » Jun 20 2018 2:49pm

Maybe look into into on the Alta Redshift... They seem to be the new benchmark, and you could get some actual proven data about pack size vs runtime.

flat tire   10 kW

10 kW
Posts: 952
Joined: Feb 26 2014 12:20am

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by flat tire » Jun 20 2018 4:22pm

Depends how fast you go, how hard you accelerate, and whether you carry momentum vs turn n burn (how frequently you accelerate). Those are the main factors. Terrain matters too, mostly how soft the ground is and whether there are inclines but riding style is the main thing.

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 20 2018 5:20pm

flat tire wrote:
Jun 20 2018 4:22pm
Depends how fast you go, how hard you accelerate, and whether you carry momentum vs turn n burn (how frequently you accelerate). Those are the main factors. Terrain matters too, mostly how soft the ground is and whether there are inclines but riding style is the main thing.
Hmmm. People smarter than me have figured out that Alta’s estimate for four hours of “expert single track” riding assumes about 1.9 hp used on average over the four hours. I race locally in “B” class in our local enduro series, so I am most likely below the Alta estimate for a given ride. Which sort of surprises me, sort of not. I’ve always felt like I’m using about 1/10 of my bikes actual power, turns out it’s about 1/20. :?

John in CR   100 GW

100 GW
Posts: 13506
Joined: May 20 2008 12:58am
Location: Paradise

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by John in CR » Jun 21 2018 11:07pm

How much gasoline do you use for your 4 hours of trail riding? That's the best way to back into how much battery you need. A gallon of gas contains 33.7kwh of energy. An electric motor is roughly 3 times as efficient as an internal combustion engine, which turns gasoline mostly into waste heat. That means for similar performance you'd need about 11kwh of battery capacity per gallon of gas used with your gas bike. IOW unless you're talking about most of the time riding easy, 4 hours of riding isn't going to happen with current battery tech. Even the top electric bikes can't be ridden hard for 4 hours using state-of-the-art high efficiency motors and battery packs that you're unlikely to match DIY.

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 21 2018 11:17pm

John in CR wrote:
Jun 21 2018 11:07pm
How much gasoline do you use for your 4 hours of trail riding? That's the best way to back into how much battery you need. A gallon of gas contains 33.7kwh of energy. An electric motor is roughly 3 times as efficient as an internal combustion engine, which turns gasoline mostly into waste heat. That means for similar performance you'd need about 11kwh of battery capacity per gallon of gas used with your gas bike. IOW unless you're talking about most of the time riding easy, 4 hours of riding isn't going to happen with current battery tech. Even the top electric bikes can't be ridden hard for 4 hours using state-of-the-art high efficiency motors and battery packs that you're unlikely to match DIY.
Good info on the gas to kWh conversion. Somehow, the Alta’s “four hours of expert single track” is coming from a 5.8 kWh battery. I go through roughly 3 gallons of gas in a four hour ride, so something is not quite right.

John in CR   100 GW

100 GW
Posts: 13506
Joined: May 20 2008 12:58am
Location: Paradise

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by John in CR » Jun 22 2018 10:14am

How you ride and the terrain and conditions (eg hard dirt or mud or sand or hills) make an extreme difference in how long your battery lasts. Even so Alta's claim sounds like absolute BS, and must be that the lightweight expert rider in ideal conditions on flat terrain trying to make the battery last as long as possible. I only ride on the street, and going for range I could make my battery last for 4 hours, 100 miles or so, however, I ride in a fun manner on my daily commute and use about half of my pack capacity each way in about 20min, and a bit more if I ride hard.

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 22 2018 11:32am

John in CR wrote:
Jun 22 2018 10:14am
How you ride and the terrain and conditions (eg hard dirt or mud or sand or hills) make an extreme difference in how long your battery lasts. Even so Alta's claim sounds like absolute BS, and must be that the lightweight expert rider in ideal conditions on flat terrain trying to make the battery last as long as possible. I only ride on the street, and going for range I could make my battery last for 4 hours, 100 miles or so, however, I ride in a fun manner on my daily commute and use about half of my pack capacity each way in about 20min, and a bit more if I ride hard.
Interesting. My favorite terrain is gnarly technical woods, where average speeds are around 10 miles an hour. Even though I ride a 2 stroke, I am almost never “on the pipe”, and I use the “soft” setting for my bike’s power valve, to reduce wheelspin. That being said, my riding buddies would say I’m a pretty aggressive rider. Not sure that provides enough info to determine if any of those motors in the above link would work for a dirt bike conversion.

I did get a response from a sur Ron rep, asking which “powertrain” I am interested in. Since I still don’t know which, if any, would be suitable, I asked for the price and availability of the biggest one :twisted: (SP180-C2 Series). We’ll see what he comes back with.

thoroughbred   100 mW

100 mW
Posts: 44
Joined: Apr 11 2018 6:18pm
Location: virginia

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by thoroughbred » Jun 22 2018 3:55pm

I'm into the same ride through trees as fast and hard as you can and still only average 10 mph stuff. I think I could ride 95% of the terrain with the power of a 50cc motor in a full size chassis. It's the last 5% that defines the riding experience, though. Some stuff has to be attacked with 40 horsepower like abrupt hillclimbs with limited runup.

The videos of the light bee at 5kW show it to be pretty agile on the trails but it does struggle on sustained hillclimbs. Maybe the 8kW Surron motor will turn out to be the sweet spot but it will take some trial and error.

81forest   100 W

100 W
Posts: 102
Joined: Jun 11 2018 12:14pm
Location: Issaquah, WA

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by 81forest » Jun 22 2018 4:55pm

thoroughbred wrote:
Jun 22 2018 3:55pm
I'm into the same ride through trees as fast and hard as you can and still only average 10 mph stuff. I think I could ride 95% of the terrain with the power of a 50cc motor in a full size chassis. It's the last 5% that defines the riding experience, though. Some stuff has to be attacked with 40 horsepower like abrupt hillclimbs with limited runup.

The videos of the light bee at 5kW show it to be pretty agile on the trails but it does struggle on sustained hillclimbs. Maybe the 8kW Surron motor will turn out to be the sweet spot but it will take some trial and error.
Exactly the same for me. I’ll post what sur Ron says as soon as I hear back.

John in CR   100 GW

100 GW
Posts: 13506
Joined: May 20 2008 12:58am
Location: Paradise

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by John in CR » Jun 23 2018 8:23am

Comparing a properly geared electric to gas motors, you need less electric hp, because of the wide torque curve starting with max torque at 0 rpm. That biggest motor may be overkill if you're going that slow, though if it's slow up really steep stuff you may need it in terms of heat generation and dissipation, which is an electric motor's true limit.

The kind of riding you're seem to be talking about is a real range and riding time killer, as low speed accelerations chew through energy. 4 gallons of gas just isn't a fair comparison at all, since the gasser is having to stop to refill the tank. The one to talk to is LiveForPhysics as he's taken the Zero offroad emoto on the most gnarly terrain, and could give realistic ride times for a given amount of battery.

phate   10 W

10 W
Posts: 70
Joined: May 28 2018 2:17am

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by phate » Jun 23 2018 3:58pm

flat tire wrote:
Jun 20 2018 12:07pm
So can you actually buy that stuff? Where?
Lol right? It came up in my parts-accumulation thread (since I haven't really built anything aside from a pile of parts and boxes yet) because I'm using a dual motor setup on my motorcycle. I wish I was still at school to make a nice clean machined case for the primary reduction, instead of the aluminum L-channel and i-haven't-decided-on-chain-or-belt-yet nightmare I'm currently looking at.

Did some reading, and it looks like if you're willing to abuse it a bit, it should be a really nice power unit for a smaller motorcycle. Not quite the power levels I'm looking for on mine, and I couldn't figure out anywhere to actually buy the thing anyways even if I wanted it. Would probably work awesome on an enduro bike with the right gearing though.

thoroughbred   100 mW

100 mW
Posts: 44
Joined: Apr 11 2018 6:18pm
Location: virginia

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by thoroughbred » Jun 27 2018 8:38pm

Whats the word from surron?

I stumbled into a Zero X bike with the 8/15 kW motor and it is plenty for trail speeds but the fine points need a bunch of work to come close to a normal gas woods bike

Aebrennan   100 W

100 W
Posts: 247
Joined: Jan 06 2017 4:08am
Location: Sydney New South Wales
Contact:

Re: Sur Ron powertrain kit for DIY moto conversion?

Post by Aebrennan » Jul 03 2018 9:52pm

I have been riding the Light Bee for over 6 months now and I am getting 70kms range from a charge. Average speed is 25-30kph with a top speed of 60kmh. I weigh 75kg and can ride the bike for 3 hours usually. My vids are on YouTube under aebikes so you can gauge the terrain and style.

Post Reply