Sur-Ron - New Mid drive Bike from China

Discussions related to motors other than hub motors.
This includes R/C motors, botttom bracket, roller and geared drives.
Locked
Voltron
100 kW
100 kW
Posts: 1320
Joined: May 02, 2013 4:53 pm
Location: Santa Barbara CA

Re: Sur-Ron - New Mid drive Bike from China

Post by Voltron » Dec 27, 2017 3:22 pm

Except the motor will be spinning so fast legs won't be able to keep up... its strictly a 4-5 mph to meet a regulation type setup.

Aebrennan
100 W
100 W
Posts: 127
Joined: Jan 06, 2017 4:08 am

Re: Sur-Ron - New Mid drive Bike from China

Post by Aebrennan » Dec 27, 2017 3:25 pm

The biggest issue for me about this bike not having pedals is I can't even ride it on jeep road and motorcycle trails or anything that is not on a closed course or private property legally. Up until a few years back, Nevada didn't have any title or registration requirements for OHV vehicles. Now we have to register EVERYTHING through the DMV . And to do that, the vehicle has to have VIN.

I can confirm that the bikes have a VIN/chassis number so this will assist with your registration process.

I can also confirm that a pedal kit is available as a kit from the factory, as i have an image of it in the spare parts catalogue.
It does not show the integration only an exploded view diagram.
I will be ordering a few of these kits with the next shipment of bikes coming to Australia/New Zealand in February.

User avatar
Rix
100 GW
100 GW
Posts: 6135
Joined: Mar 29, 2012 11:26 am
Location: Fallon NV USA

Re: Sur-Ron - New Mid drive Bike from China

Post by Rix » Dec 27, 2017 4:59 pm

Aebrennan wrote:
Dec 27, 2017 3:25 pm
[] The biggest issue for me about this bike not having pedals is I can't even ride it on jeep road and motorcycle trails or anything that is not on a closed course or private property legally. Up until a few years back, Nevada didn't have any title or registration requirements for OHV vehicles. Now we have to register EVERYTHING through the DMV . And to do that, the vehicle has to have VIN.

I can confirm that the bikes have a VIN/chassis number so this will assist with your registration process.

I can also confirm that a pedal kit is available as a kit from the factory, as i have an image of it in the spare parts catalogue.
It does not show the integration only an exploded view diagram.
I will be ordering a few of these kits with the next shipment of bikes coming to Australia/New Zealand in February.



Just clarifying, this bike comes with a 17 digit manufacture VIN number on the frame? That does open up the doors. The pedal kit would still negate the requirement to register at the DMV as an OHV. By chance, can one order a larger sprocket for the rear? say 4T bigger? Turn this thing into a hill climber.

Aebrennan
100 W
100 W
Posts: 127
Joined: Jan 06, 2017 4:08 am

Re: Sur-Ron - New Mid drive Bike from China

Post by Aebrennan » Dec 27, 2017 5:03 pm

I will confirm the number of digits in the VIN and advise.

The catalogue shows 2 sizes for motor gear and 3 sizes for rear sprockets.

I will be ordering all available options and advise once I have them.

I have been in communication with the factory for months and was not told about any of these options, it is only since receiving the documentation I now know this information.

User avatar
Rix
100 GW
100 GW
Posts: 6135
Joined: Mar 29, 2012 11:26 am
Location: Fallon NV USA

Re: Sur-Ron - New Mid drive Bike from China

Post by Rix » Dec 28, 2017 12:51 am

Aebrennan wrote:
Dec 27, 2017 5:03 pm
I will confirm the number of digits in the VIN and advise.

The catalogue shows 2 sizes for motor gear and 3 sizes for rear sprockets.

I will be ordering all available options and advise once I have them.

I have been in communication with the factory for months and was not told about any of these options, it is only since receiving the documentation I now know this information.
Interesting, look forward to hearing from you.

User avatar
Alex Imreh
10 W
10 W
Posts: 80
Joined: May 20, 2015 8:27 pm
Location: Cluj-Napoca, Romania
Contact:

Re: Sur-Ron - New Mid drive Bike from China

Post by Alex Imreh » Dec 28, 2017 4:21 am

For pedal system check this video - Kick Pedal System Assembly - https://www.youtube.com/watch?v=FVl66T8 ... e=youtu.be

User avatar
parabellum
1 MW
1 MW
Posts: 1976
Joined: Nov 19, 2010 9:55 am
Location: Dominican Republic, north.

Re: Sur-Ron - New Mid drive Bike from China

Post by parabellum » Dec 28, 2017 8:24 am

Alex Imreh wrote:
Dec 28, 2017 4:21 am
For pedal system check this video - Kick Pedal System Assembly
And that totally screws the gear ratio to the motor. Ingenious!
Am I missing something?

User avatar
fechter
100 GW
100 GW
Posts: 11976
Joined: Dec 31, 2006 3:23 pm
Location: California Bay Area, USA

Re: Sur-Ron - New Mid drive Bike from China

Post by fechter » Dec 28, 2017 9:01 am

parabellum wrote:
Dec 28, 2017 8:24 am
And that totally screws the gear ratio to the motor. Ingenious!
Am I missing something?
Hmm... no, I don't think you're missing anything. It should go 60mph with the new rear sprocket.
That certainly looks like it could be improved on.
"One test is worth a thousand opinions"

dirkdiggler
10 kW
10 kW
Posts: 739
Joined: Oct 18, 2012 1:31 am

Re: Sur-Ron - New Mid drive Bike from China

Post by dirkdiggler » Dec 28, 2017 4:44 pm

I might be mistaken here, but if the chain length doesn't decrease wouldn't the gear ration be the same? The wheel isn't going to turn any faster, as it has to go around the gearing of the pedal system's gear also. Does that make any sense?

Crazy way to make a "compliance" vehicle though. Seems like a good idea to basically have the pedal system barely touching the chain. Only having a few teeth engage, instead of wrapping the whole chain around a sprocket and adding more complexity.

My bike is on its way finally. Looking forward to getting some rides.

User avatar
scrambler
100 W
100 W
Posts: 234
Joined: Aug 10, 2015 7:23 pm
Location: San Francisco Bay Area (USA)

Re: Sur-Ron - New Mid drive Bike from China

Post by scrambler » Dec 28, 2017 6:26 pm

dirkdiggler wrote:
Dec 28, 2017 4:44 pm
I might be mistaken here, but if the chain length doesn't decrease wouldn't the gear ration be the same? The wheel isn't going to turn any faster, as it has to go around the gearing of the pedal system's gear also. Does that make any sense?
The chain is not the same. He is attaching a new (shorter) chain to the old (longer) one to make it easy to pass it over the motor sprocket which is not easily accessible. Because the video is sped up, you can see him removing the old long one.

I have several issues with this kit:
He is going from about 60 teeth to 25 teeth at the back, this means the bike will loose 60% of its torque and go way fast on throttle.
The distance between the seat the pedals appears to be ridiculously small, so it looks like pedaling a kid tricycle...
You only have a 1:1 ratio for pedaling, so this will be a very small pedaling range.

To make this a usable pedaling bike, they would need to create a separate chain between BB and motor or between BB and rear wheel.
I cant tell if there is any space to mount a freewheel sprocket next to the motor sprocket.
Creating a second chain between BB and rear whel may be easier by creating an adpater that would fit a second sprocket next to the 60 teeth existing one. Although unless the BB would have a freewheel, I am not sure how you could adapt a freewheel sprocket on the existing 60 teeth one.

For gears, the only solution I can think of would be to mount something like a pinion gearbox in place of the BB. Looking at the video, there may actually be space for one, but one would have to design and built a mounting adapter.

Last would be to raise the Seat and handlebar, not sure how workable that is.

All in all, I think it would take a lot more thoughts and execution to make a usable pedaling kit on this bike that could resemble what they did on the Neematic (except may be with the secondary chain being between BB and rear wheel).
If this is the Kit Luna plans to sell, I am not sure it has much value.

Just some thoghts :)
Last edited by scrambler on Dec 28, 2017 10:23 pm, edited 1 time in total.

dirkdiggler
10 kW
10 kW
Posts: 739
Joined: Oct 18, 2012 1:31 am

Re: Sur-Ron - New Mid drive Bike from China

Post by dirkdiggler » Dec 28, 2017 7:43 pm

Didn't see them change out the chain. I like my idea better than what Sur-ron is doing. Keep the same sprocket on the wheel and just have a small sprocket on the pedals that just engages a few teeth on the chain. Nobody is pedaling this thing anyway. How long is the motor going to last with them tripling(or thirding?) the ratio? Crazy! I imagine they will quickly find out it's over geared this way.

User avatar
macribs
1 GW
1 GW
Posts: 3291
Joined: Jul 22, 2014 5:59 pm

Re: Sur-Ron - New Mid drive Bike from China

Post by macribs » Dec 28, 2017 8:01 pm

Ok that was prototype v0.1. Now lets wait for the alpha and then beta release before biting.
Seems they just about removed all the fun from the Sur Ron, by choking the torque into nothing. No more fast acceleration, no more hill climb and no breeze to pedal either. I think they need to take a good look at the motoped, that was a working solution to the pedal problem. This China solution is just messing up the entire ride, removing all torque and leave a neutered bike that is good for nothing. No fun riding, no fun pedaling and no fun climbing.

User avatar
Rix
100 GW
100 GW
Posts: 6135
Joined: Mar 29, 2012 11:26 am
Location: Fallon NV USA

Re: Sur-Ron - New Mid drive Bike from China

Post by Rix » Dec 28, 2017 11:27 pm

He is going from about 60 teeth to 25 teeth at the back, this means the bike will loose 60% of its torque and go way fast on throttle.
The distance between the seat the pedals appears to be ridiculously small, so it looks like pedaling a kid tricycle...
You only have a 1:1 ratio for pedaling, so this will be a very small pedaling range.
Yep, thats exactly right, loosing 60% torque :shock: . This bike isn't that fast off the line with the 60T. Jay noted, his Alpha with peak watts turned down to 5.99 was quicker. With a 25T this thing wont pull any quicker off the line than a 750w geared hub motor. Yah, it will probably go 60MPH if there is enough room to get up to speed and no head wind, but the trade off is not worth it. If anything, I would want to gear the rear up to 65T or 70T and pick up another 8-16% of torque at the price of a loss of top speed. The pedal kit does satisfy the issue I addressed, but now this machine will need all the help you can give it pedaling to accelerate with that 25t rear.

User avatar
macribs
1 GW
1 GW
Posts: 3291
Joined: Jul 22, 2014 5:59 pm

Re: Sur-Ron - New Mid drive Bike from China

Post by macribs » Dec 29, 2017 12:17 am

Rix I think you are way to nice here. When people said that the pedal for legal reason was a thing, I bet you not even a single person was thinking of a solution where more then half the torque was gone. I mean what is the point of a mid drive if not having plenty of torque? I would say the problem regarding the legal issue did not get solved - because the way they "solved" it take away the benefits from the bike.

This legal issue could be solved a lot smarter. Ie a left side chain for pedals, with free wheel. Or as on the motoped, with another sprocket on the jackshaft where the chain from the pedals goes onto a free wheeling sprocket.

Here is a solution from one of Matt's mid drive builds, notice the crank with pedals. That front sprocket connects to a right side rear sprocket via chain. There is you correct gearing for pedaling, yet left side chain for motor can run whatever gearing works best for the rider, without any conflicts with regards to the pedals.

Image

Now here is a solution for free wheel on a jackshaft axle. Notice the bb and pedal is attached to a front sprocket. And this goes to a free wheeling jack shaft sprocket.

Image

Here you can see the whole setup. The motor drives the jackshaft. The jackshaft got a set of free wheeling sprockets for the pedal front sprocket. Now the pedal will drive the jackshaft as well, and in turn the rear wheel. Not as much choice of gearing unless paired with a internal gearbox stealth fighter style (don't remember the brand name)

Now both of these solutions are smart solutions to the same problem. And this is approach is the way to solve the legal issue. Not by ruining the torque or by altering important features of the bike.

User avatar
knoxie
100 MW
100 MW
Posts: 2542
Joined: Jan 03, 2007 5:54 pm
Location: UK
Contact:

Re: Sur-Ron - New Mid drive Bike from China

Post by knoxie » Dec 29, 2017 7:51 am

why do the peddles need to actually do anything? ive been riding ebikes on the road for 20 years, in all that time I have been stopped by the police once (and I ride my bike every day to work) in most of that time my bike has been going so fast that the peddles make no difference I simply move my legs to make it look less obvious, the time I was stopped the cops hardly noticed the motor and batteries even though it was plenty obvious.

If it were me and I wanted to use this thing on the road I would simply fit the peddle kit but leave the chain as it is, as long as they see your legs moving you will likely never get stopped, if you do get stopped the cops got to know to check the drive train,they wont and if you are involved in an accident the lack of a pedal drive train will be the least of your problems as even if you did have a proper chain attached just on the measured power alone you would be in trouble.

I would love one of these bikes, I would use if mainly off road but would fit dummy peddles to make it look legit in-between me getting from my house to my local trails.
Electric KMX 72V Lipo, USPD drive unit. BMX 72V, Puma BMC,
Raleigh 26 inch MTB Puma 50V Turnigy 25C Lipo 10AH, Trek MTB, X5 48V NIMH. Electric BMX
http://tinyurl.com/4vrmc8 http://tinyurl.com/3umm4n

User avatar
Alex Imreh
10 W
10 W
Posts: 80
Joined: May 20, 2015 8:27 pm
Location: Cluj-Napoca, Romania
Contact:

Re: Sur-Ron - New Mid drive Bike from China

Post by Alex Imreh » Dec 29, 2017 9:12 am

macribs wrote:
Dec 29, 2017 12:17 am
Here is a solution from one of Matt's mid drive builds
Image

Please on the Matt build this is to attach a front derailleur?
front derailleur.jpg
front derailleur.jpg (128.08 KiB) Viewed 411 times

User avatar
macribs
1 GW
1 GW
Posts: 3291
Joined: Jul 22, 2014 5:59 pm

Re: Sur-Ron - New Mid drive Bike from China

Post by macribs » Dec 29, 2017 9:18 am

+1 knoxie.

Take it one step further, don't even mount the pedals. Just put them in a vice and give em a nice bend and a few scratches. Enough angle so that they would be impossible to use. Put them in your backpack and use it as a "prop for show and tell" if you ever do get stopped by the police.

"No you see sir, I had a mild crash sir, and I ruined my pedals, so I had to remove them in order to get home safely". Yes thank you sir, I will make sure I get new pedals mounted right away when I get home".

User avatar
Hyena
100 GW
100 GW
Posts: 6057
Joined: Aug 13, 2008 9:10 am
Location: Sydney, Australia
Contact:

Re: Sur-Ron - New Mid drive Bike from China

Post by Hyena » Dec 29, 2017 9:35 am

mr.electric wrote:
Dec 26, 2017 11:28 pm
I heard the ebike battery was developed here in the USA by a few key engineers a few of them actually ESers....and they work on a team with the L word.
If those members could tell us what input they had in the bikes design I'm sure alot of us would be keen to hear the story.
Out of the box this bike performs amazingly well which is uncharacteristic for a Chinese export that popped up out of the blue. It makes sense they had help but I assumed Luna had come along after the fact and just added it to their catalog.
If you had to gamble a kidney on an engineer with mx and battery experience aligned with Luna the immediate answer is Luke liveforphysics, but according to this review the bike was new to him, and the battery contents were a surprise to Luna and quote “The best ebike pack they have ever seen come out of China.”
Luke ‘Live for Physics’ and I took out this bike several times while I was at Luna and he was downright enthusiastic about it. His first impression when riding this bike was “China … doing it right”. High praise for someone who worked for many years to bring Zero to where it stands today as the absolute leader in electric motorcycles in the USA. They ripped apart the 32Ah PF cell pack and claimed that it was “The best ebike pack they have ever seen come out of China.” Wow, just wow.
https://electricbike-blog.com/2017/12/1 ... dirt-bike/

Alternative facts ?
I also heard of big upgrades that Luna is going to offer very soon "for off road use only"
Every aspect of the bike right now, and in any form, is for offroad use only. Sounds like marketing buzz words
you will be able to run over 15k continuous watts with a fov sine wave controller (a modipus unit) and upgraded battery and bms...
You mean FOC, and Mobipus ? Either way, Nope. The bike uses a modified GM HPM3000 which is rated at 3kw. It handles 6kw peak brilliantly and I dare say you could push it to 10kw peak but a genuine 15kw continuous, no way. Above this motor GM have a larger 5kw and 10kw rated motor. The 10kw motor will do 15kw but there's no way that will fit in this frame.


Anyway back on topic, as covered above that pedal kit from surron is token at very best and generally a bit of a joke. Ground clearance would be terrible for actual offroad riding, the crank arms are short and inefficient, only a few teeth contacting the chain and you couldn't pedal it at more than maybe 10km/hr with the new rear cog. You'd also drastically lose torque with the smaller rear sprocket so it'd become boring and incapable offroad, and you'd then gain alot of top speed which you don't need and would be impractical anyway. As knoxie said, if you were going to do it at all you'd want to leave the stock gearing to retain the actual good aspects of the bike. Only problem then is you're back to akward footing on pedals rather than foot pegs. And I just don't know any variation of the design where you can make this comfortable or practical to sit on and pedal with the fixed (low) seat height.

I think what we've all been doing over the years in making our bicycles basically cross over electric dirt bikes is a better prospect than trying to make this dirt bike more of a bicycle. You can make a pretty damn good electric bicycle that rides as well as a dirt bike in alot of situations. But any thing you do to an electric dirt bike like this is going to make it a much more inferior bicycle
www.HyenaElectricBikes.com
Aussie high powered e-bike kits and custom performance ebikes
New FUTR and Hyena special edition Beta frames now available!
My build and HD video thread____. My youtube channel____ Hyena Facebook page
My bike is writing cheques my body can't cash...

User avatar
Alex Imreh
10 W
10 W
Posts: 80
Joined: May 20, 2015 8:27 pm
Location: Cluj-Napoca, Romania
Contact:

Re: Sur-Ron - New Mid drive Bike from China

Post by Alex Imreh » Dec 29, 2017 11:44 am

macribs wrote:
Dec 29, 2017 9:18 am
+1 knoxie.
Take it one step further, don't even mount the pedals. Just put them in a vice and give em a nice bend and a few scratches. Enough angle so that they would be impossible to use. Put them in your backpack and use it as a "prop for show and tell" if you ever do get stopped by the police. "No you see sir, I had a mild crash sir, and I ruined my pedals, so I had to remove them in order to get home safely". Yes thank you sir, I will make sure I get new pedals mounted right away when I get home".
Have you seen the Strava trials above made with FireFly? I would say next step is possible in a few years maybe if battery technology will have bigger energy density at lower cost. For the moment this bike could be fun for countryside but range is not enough for any decent trails, maybe you can go up one moutain but than you must come back, 70% battery consumption at a dozen of km not enough. So for the moment next step is back, i would rather look for speed pedalecs, real bicycles with real pedalling and good gears, gropusets, to make real 100km offroad range. Battery / frame similar with Firefly but engine smaller and as i said real bicycle with real pedalling.

User avatar
Rix
100 GW
100 GW
Posts: 6135
Joined: Mar 29, 2012 11:26 am
Location: Fallon NV USA

Re: Sur-Ron - New Mid drive Bike from China

Post by Rix » Dec 29, 2017 12:22 pm

[quote=macribs post_id=13
Rix I think you are way to nice here. When people said that the pedal for legal reason was a thing, I bet you not even a single person was thinking of a solution where more then half the torque was gone. I mean what is the point of a mid drive if not having plenty of torque? I would say the problem regarding the legal issue did not get solved - because the way they "solved" it take away the benefits from the bike.

[/quote]

Hey Mac, read your post and liked that San Andreas home built by Matt, looks very like a motoped set up from the bottom. Anyway, I agree, with the pedal kit, Sur-Ron missed it with the gearing changed and like you said, there are better ways to get functional pedals on it. The reason I was being nice about the whole comment was because in stock trim, its a very good bike with a very good price. I don't want to loose sight of that fact. When Hyena said he was going to leave it stock and not touch it, that told me all I needed to know. It was designed as light electric E-motor cycle, kind of like an FX Bike out of New Zealand http://www.fxbikes.com/. There is no doubt that if people can live without the ability to pedal, this bike for the buck is as good as anyone will get.

User avatar
Hyena
100 GW
100 GW
Posts: 6057
Joined: Aug 13, 2008 9:10 am
Location: Sydney, Australia
Contact:

Re: Sur-Ron - New Mid drive Bike from China

Post by Hyena » Dec 29, 2017 7:22 pm

How NOT to ride the Surron!

www.HyenaElectricBikes.com
Aussie high powered e-bike kits and custom performance ebikes
New FUTR and Hyena special edition Beta frames now available!
My build and HD video thread____. My youtube channel____ Hyena Facebook page
My bike is writing cheques my body can't cash...

User avatar
efMX Trials Electric Freeride
10 kW
10 kW
Posts: 837
Joined: Feb 15, 2013 4:43 pm

Re: Sur-Ron - New Mid drive Bike from China

Post by efMX Trials Electric Freeride » Dec 29, 2017 7:30 pm

have you seen the "Mammoth" ebike yet??
seems to maybe check many of your boxes..
enduro design, up to 100km range, wide range 9 speed sequential gear box for the pedal transmission..

mammothebike.com
Alex Imreh wrote: ...
The main reason to build something similar with pedals is to have longer range to do real trails. My first motorcycle, the one I used to learn biking was a Yamaha WR250F quite a few years ago 120kg weight. My target is to make trails i did with that gas enduro, to make over 100km offroad and with serious uphills, with electric bikes at half weight compared to modern gas enduros.
There will be never enough options, the game is just starting, there will be more and more hybrid models, somewhere between downhill bikes, light enduro motorcycles, speed pedalecs and so on. At present level of lithium technology the only way to make 100km offroad, or 200km onroad is with pedals, that is at a price level well under 5000euro.

Others could use same frame with power hubs, we still have bits of a free world, let people talk about legality, noise, let MTBs complain about the immorality of enduro bikes, I will do what i want what i like, others will do same. If someone can use his "illegal" bike on trails, in the countryside, that is his own business in my opinion
4# But a big battery does not implies an illegal bike. If the engine is relatively small we will have a legal speed pedalec, NO NEED for EU homologation, no need for plate/insurrance, that will also mean a long range. Small bike builders can compete on this area, big companies will have an advantage when it comes to EU homologations.

But the game is just beginning, there will be a golden age for ebikes, many more hybrid models to come and hopefully more and more builders will be able to start business, go to the next level of the game - ie small production. Cooperation could be the best way..
some ride & sk8 videos:
metacafe.com/channels/NATAS666DAMIEN
http://www.youtube.com/natas666damien
i have nothing for sale.. :)

User avatar
macribs
1 GW
1 GW
Posts: 3291
Joined: Jul 22, 2014 5:59 pm

Re: Sur-Ron - New Mid drive Bike from China

Post by macribs » Dec 29, 2017 7:49 pm

@hyena yeah powerful bikes can cause that. I got to say he did well tough. He was upon his feet before bike was stationary, and had almost a ninja like tuck and roll going there. All he got to show for it was a tiny road rash. He did well. Either cat like reflexes or some part ninja.

User avatar
DasDouble
100 kW
100 kW
Posts: 1019
Joined: Jul 12, 2015 1:35 pm
Location: GERMANIA :D

Re: Sur-Ron - New Mid drive Bike from China

Post by DasDouble » Dec 29, 2017 8:43 pm

Hyena wrote:
Dec 29, 2017 7:22 pm
How NOT to ride the Surron!

Oh damn, just saw that on my subscrition box on yt. Shit happens lol.. No, seriously, I made a similar mistake, when I tried to wheelie my bike. Endresult: Broken rear shock and some more mails with Anastasia hahaha :D :roll: :D

Edit: hope the bike is ok.

Edit 2: Hope the guy is also ok lol :mrgreen:
Highpower Ebike enthusiast.
-Built own ebike: ✔
-Built own 3.2kWh LiIon battery (300Amps): ✔
-Overtake Porsche with own Ebike: ✔
-Take off with ebike: ✖

~14kW, 3.2kWh LiIon, QS 205 8ml ff, hubsink

User avatar
fechter
100 GW
100 GW
Posts: 11976
Joined: Dec 31, 2006 3:23 pm
Location: California Bay Area, USA

Re: Sur-Ron - New Mid drive Bike from China

Post by fechter » Dec 29, 2017 10:44 pm

efMX Trials Electric Freeride wrote:
Dec 29, 2017 7:30 pm
have you seen the "Mammoth" ebike yet??
seems to maybe check many of your boxes..
enduro design, up to 100km range, wide range 9 speed sequential gear box for the pedal transmission..

mammothebike.com
Mammoth ebike.JPG
Mammoth ebike.JPG (68.85 KiB) Viewed 289 times
Interesting transmission. Something similar to that might work for the SurRon. Take the pedal input and gear it way faster to match the chain speed.

Hyena wrote:
Dec 29, 2017 7:22 pm
How NOT to ride the Surron!

Watching that reminds me of Luke's DeathBike. Nice recovery but nasty road rash. Be careful!
"One test is worth a thousand opinions"

Locked