Sur-Ron - New Mid drive Bike

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 3:06am

Grantmac wrote:
Dec 24 2018 2:59am
Don't confuse torque and HP. The motor is 3Kw ~4hp, gearing it down by any amount doesn't increase its HP.
Right. I didn't say being geared down is the same as actual horsepower. In fact, I said (emphasis added):
I know gearing down isn't exactly the same as pure HP (since it has to develop RPMs), but the experienced torque would be similar,
So clearly I was talking about torque. ;)
Grantmac wrote:
Dec 24 2018 2:59am
I'm with motomoto, I'd be interested in a Sur-Ron if it was +10kw otherwise it's just a heavy ebike without pedals.
Possibly, but for the money, I don't think it can be beaten. What even comes close?

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Dec 24 2018 5:22am

I want to get a 500lb and a 550lb spring for my Fastace shock. Does anyone know the inner diameter or what common bike brand springs like Fox or Rockshox fit it? What's the shock's stroke length?

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Re: Sur-Ron - New Mid drive Bike

Post by artisanstone » Dec 24 2018 8:16am

artisanstone wrote:
Dec 22 2018 10:30am
Any opinions on this setup?

https://www.youtube.com/watch?v=vn6KZPyvOZ4

It would be awesome if someone put together a plugnplay version of this. lipos in a surron battery case, fully programmed controller, etc. It looks to me like the right amount of power without going too far.
I'm gonna repost this. I think he says it's 8kw, BAC4000. Maybe he's on here?

I think 15kw or so would be ideal. For me the extra power would be used only when needed, maybe 10% of the time. I doubt it would decrease range that much. We have other limitations for using power like traction at the rear wheel.

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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 » Dec 24 2018 9:12am

artisanstone wrote:
Dec 24 2018 8:16am
artisanstone wrote:
Dec 22 2018 10:30am
Any opinions on this setup?

https://www.youtube.com/watch?v=vn6KZPyvOZ4

It would be awesome if someone put together a plugnplay version of this. lipos in a surron battery case, fully programmed controller, etc. It looks to me like the right amount of power without going too far.
I'm gonna repost this. I think he says it's 8kw, BAC4000. Maybe he's on here?

I think 15kw or so would be ideal. For me the extra power would be used only when needed, maybe 10% of the time. I doubt it would decrease range that much. We have other limitations for using power like traction at the rear wheel.
the video is from ASI dealer on here Electric Race Technology :
https://endless-sphere.com/forums/viewt ... 4#p1430494
some ride & sk8 videos:
metacafe.com/channels/NATAS666DAMIEN
http://www.youtube.com/natas666damien
i have nothing for sale.. :)

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Re: Sur-Ron - New Mid drive Bike

Post by artisanstone » Dec 24 2018 9:45am

Cool, thanks. I remember seeing that now.

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Offroader   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 24 2018 11:01am

3DTOPO wrote:
Dec 24 2018 1:31am

I'd use both. Brush some of that stuff on the threads then put a couple wraps of teflon tape on.
Thanks I never heard of using teflon tape but I'll look into it.

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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 » Dec 24 2018 11:04am

Offroader wrote:
Dec 24 2018 11:01am
3DTOPO wrote:
Dec 24 2018 1:31am

I'd use both. Brush some of that stuff on the threads then put a couple wraps of teflon tape on.
Thanks I never heard of using teflon tape but I'll look into it.
blue thread lock is available as tape but most ppl are more familiar with the liquid variety..
some ride & sk8 videos:
metacafe.com/channels/NATAS666DAMIEN
http://www.youtube.com/natas666damien
i have nothing for sale.. :)

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 24 2018 11:14am

Lelandjt wrote:
Dec 24 2018 5:22am
I want to get a 500lb and a 550lb spring for my Fastace shock. Does anyone know the inner diameter or what common bike brand springs like Fox or Rockshox fit it? What's the shock's stroke length?
The fast ace is a 10.5" length shock which should have a 3.5" stroke, from trying to measure the stroke on the bike it looks to be 3.5". As you probably discovered you can't easily buy fastace springs so you will have to buy some other brand, which is OK from what I've read and done often in biking.

Without taking the fast ace rear shock out and measuring the fast ace spring, the 10.5" x 3.65" stroke springs by FOX should work. The 10.5" is the shock length and not the spring length, but the springs are called 10.5". For some reason fox only sells 3.65" stroke shocks and not 3.5" stroke, but this is what they sell for their 3.5" stroke shocks.

The fox springs for the 10.5" shocks has a length that is exactly the same as the fast ace, the outer diameter is close, but the fastace spring seems to be about 2mm wider, which doesn't matter. Since the fast ace has a 3.5" stroke, you just need a spring rated for a 3.5" stroke or higher.

I read where spring fitment depends only on the inner diameter of the spring, which the fox spring I measure about 37mm inner diameter. I can't measure the fastace without removing it.

If you want to make sure the fox spring will work you can remove the fastace spring and check to see if an inner diameter of about 35.5 mm will fit on the spring brackets grooves. Or you can measure the inner diameter somehow of the fast ace spring then you will know if the fox spring will work.

I did read that there are a couple of inner diameter springs depending on brand, so if you really want to make sure you will have to remove the fastace spring and check the inner diameter. If you do check it report back on what you find. Everything else matches perfectly with the fox 10.5x3.65 springs.

The only place I know to order 10.5 x 3.65 springs, and I've ordered a few from fox, is calling fox directly on the phone. The prices are reasonable.

https://www.ridefox.com/fox17/contact.php?ref=footer

EDIT: in the picture you can see what you will need to measure. The shock collar measures about 34.5 mm on the fox shocks and the fox springs have 35.5mm inner diameter. If the fast ace has this larger than 35.5mm, you can't use fox springs

I also found this in another forum

There are 3 dirrefent spring ID's for coil shocks:
Smallest is Fox, which is the only one using this size: 1.38" or 35.05mm
Almost every other brand, including Cane Creek, Marz, etc. are all 1.43" or 36.32mm
Then the largest is the Vivid which uses a 1.5" or 38.1mm

As such, Fox specific springs will not fit on any other shock collars (note besides Fox springs RCS also makes Fox specific Ti springs). The 1.43" springs will work on Fox shocks, but they will walk around a bit on the collars, even under preload, when you ride. The Vivid springs really should'nt be used on any of the others as the size difference is enough that the spring will more than just walk around on the collars. They wont sit on there correctly.


so all of this being said, just remove the fast ace shock and measure the shock collar diameter and we can figure out what will work.

Image

Lelandjt   100 mW

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Re: Sur-Ron - New Mid drive Bike

Post by Lelandjt » Dec 24 2018 1:11pm

Thanks. Apparently Fox only makes 3.5" springs up to 500lbs so I've got one of those on the way. If it's not stiff enough I'll source a 550 elsewhere.

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » Dec 24 2018 2:24pm

3DTOPO wrote:
Dec 24 2018 3:06am
Grantmac wrote:
Dec 24 2018 2:59am
Don't confuse torque and HP. The motor is 3Kw ~4hp, gearing it down by any amount doesn't increase its HP.
Right. I didn't say being geared down is the same as actual horsepower. In fact, I said (emphasis added):
I know gearing down isn't exactly the same as pure HP (since it has to develop RPMs), but the experienced torque would be similar,
So clearly I was talking about torque. ;)
Grantmac wrote:
Dec 24 2018 2:59am
I'm with motomoto, I'd be interested in a Sur-Ron if it was +10kw otherwise it's just a heavy ebike without pedals.
Possibly, but for the money, I don't think it can be beaten. What even comes close?
4hp isn't much power no matter what kind motor is producing it. Sure an electric can produce torque at zero rpm but that doesn't make it equivalent to even a very slow dirt bike like a 4 stroke 125. Being able to lift the front wheel on power under 15mph is pretty much a requirement for an off road bike.

For the money I'd rather do a 4-6kw mid drive DH frame build. A bit less weight, actual pedals and way further under the radar.
What the Sur-Ron has is a turn key platform but if it can't do basic dirt bike stuff without mods then it's not exactly turn key.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 24 2018 3:00pm

I believe the issue with the Sur-Ron is that the controller is limiting the torque at lower speeds. With a new controller and say upping the power just by a little, this thing would have more than enough torque. It would be able to lift the front up way too easily.

I think Sur-Ron purposely is putting limits on the phase amps, and this is the reason why it lacks torque. If they didn't do that it would be way too powerful at lower speeds.

My hub bike has no issue with lifting the front wheel up, and that doesn't have the gearing advantage of the Sur-Ron.

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Dec 24 2018 3:20pm

What do you guys think of the looks? I kind of looks like it came stock with the bike.

I bought this rear fender for my other bike and never used it so I made a mount for it to use on my Sur-Ron. It is temporary until someone makes a decent fender for the Sur-Ron. The fender and mount weigh in at 14 oz.

I milled the bracket out of Delrin plastic I had laying around. If I push on the fender there is slight movement / twist in the bracket. I'm really not sure what causes the movement, it almost looks like the M5 bolts I used move slightly, possibly it is the Delrin plastic, maybe both. The Delrin is such a large piece it is hard to imagine that will flex. The other issue is where the mount sits on the frame is not flat.

I didn't test it yet, but it is wide and long so it should stop a lot of mud/water.

The front fender is a mucky nutz which I like as it is small, light weight, and surprisingly effective for its small size.

Image

Image

Image

The mud is from before I mounted the fender. The mount is just temporary so it looks like crap
Image

Image

Image

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Rix   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Dec 24 2018 4:32pm

Nicely done Offroader, that will keep the mud off your backside.

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 5:25pm

efMX Trials Electric Freeride wrote:
Dec 24 2018 11:04am
Offroader wrote:
Dec 24 2018 11:01am
3DTOPO wrote:
Dec 24 2018 1:31am

I'd use both. Brush some of that stuff on the threads then put a couple wraps of teflon tape on.
Thanks I never heard of using teflon tape but I'll look into it.
blue thread lock is available as tape but most ppl are more familiar with the liquid variety..

I was actually thinking of the plumbing teflon tape sold for making threads water tight. It costs like $1 for a roll. It’s amazing stuff, pull it tight around the threads, and usually it doesn’t get torn even after mating it in the hole. If so, it would completely eliminate any direct contact and can’t be washed away.

Grantmac wrote:
Dec 24 2018 2:24pm
For the money I'd rather do a 4-6kw mid drive DH frame build. A bit less weight, actual pedals and way further under the radar.
What the Sur-Ron has is a turn key platform but if it can't do basic dirt bike stuff without mods then it's not exactly turn key.
For me, the proof is in the pudding. I live in the mountains with thousands of miles of technical ridding out the front door. There is practically nothing I can’t do on the Sur Ron that can be done on a 250cc. I went for a ride behind a 250 and I could totally keep pace. He had a bit faster acceleration, but the roads/trails here are so windy that he could not lose me.

The kid on the 250 grew up here riding. I let him take out the Sur Ron, and the first thing he said when he got back, with a great big grin, is “I’m SELLING my 250!!!”.

So saying it can’t do basic dirt bike stuff is laughable.

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Re: Sur-Ron - New Mid drive Bike

Post by Chilli P » Dec 24 2018 5:40pm

3DTOPO wrote:
Dec 24 2018 5:25pm
efMX Trials Electric Freeride wrote:
Dec 24 2018 11:04am
Offroader wrote:
Dec 24 2018 11:01am
3DTOPO wrote:
Dec 24 2018 1:31am

I'd use both. Brush some of that stuff on the threads then put a couple wraps of teflon tape on.
Thanks I never heard of using teflon tape but I'll look into it.
blue thread lock is available as tape but most ppl are more familiar with the liquid variety..

I was actually thinking of the plumbing teflon tape sold for making threads water tight. It costs like $1 for a roll. It’s amazing stuff, pull it tight around the threads, and usually it doesn’t get torn even after mating it in the hole. If so, it would completely eliminate any direct contact and can’t be washed away.

Grantmac wrote:
Dec 24 2018 2:24pm
For the money I'd rather do a 4-6kw mid drive DH frame build. A bit less weight, actual pedals and way further under the radar.
What the Sur-Ron has is a turn key platform but if it can't do basic dirt bike stuff without mods then it's not exactly turn key.
For me, the proof is in the pudding. I live in the mountains with thousands of miles of technical ridding out the front door. There is practically nothing I can’t do on the Sur Ron that can be done on a 250cc. I went for a ride behind a 250 and I could totally keep pace. He had a bit faster acceleration, but the roads/trails here are so windy that he could not lose me.

The kid on the 250 grew up here riding. I let him take out the Sur Ron, and the first thing he said when he got back, with a great big grin, is “I’m SELLING my 250!!!”.

So saying it can’t do basic dirt bike stuff is laughable.
Hi guys, first post on here I have to completely agree, this bike is way more comparable in performance to a dirt bike than a mid drive e bike, way more capable and so much stronger it's laughable saying the Sur Ron can't do dirt bike stuff and e bike and Sur Ron are comparable. In saying that the Sur Ron can certainly be used in places the e bike can but its just as capable going motocycle speed on trails and climbing hills only motocycles can.

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Re: Sur-Ron - New Mid drive Bike

Post by freeflow » Dec 24 2018 6:05pm

So, after basically reading all posts in this thread (which has been very helpful in deciding to buy or not) I submit my first reply.

I got my bike in October and I have done a couple of charges on it. I got the fully legal EU model for later registration (have removed all lights for now) to ride on the trails behind the house. Right now we have snow so I purchased a pair of cheap mx tires and fitted them with studs and the grip is better than ever.

Thanks for all the post as mentioned, it helped with the decision. The bike has its pros and cons but I sure ride more than ever (also have a Yamaha 450) and the biggest for me is the simplicity to just go out on the trails behind the house which I can't with my 450. It's far from the same type of bike but I get a chance to ride more often.

Studded tires https://imgur.com/a/Dt1FszP

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 6:20pm

freeflow wrote:
Dec 24 2018 6:05pm
Studded tires https://imgur.com/a/Dt1FszP
Nice tires! I've been riding every day in the ice and snow. Snow is fun, it is the ice that isn't!

What model/make is that tire? Studded tires would help a lot on the ice. Did you stud them yourself?

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Re: Sur-Ron - New Mid drive Bike

Post by freeflow » Dec 24 2018 6:32pm

The tire is Razorback Feral 70/100 -19 and I mounted the studs myself. Really easy it just takes time but with a power drill it goes pretty fast.

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 6:36pm

freeflow wrote:
Dec 24 2018 6:32pm
The tire is Razorback Feral 70/100 -19 and I mounted the studs myself. Really easy it just takes time but with a power drill it goes pretty fast.
Thanks! I guess they are self-threading? eg. you didn't drill a hole for them? What type of studs?

I have the (brand-new) stock tire laying around, thinking I might stud it. Thanks!

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » Dec 24 2018 6:48pm

Sorry guys but not being able to making it up +18" steps and over logs means it won't work around here. So if it can't at least wheelie then it's definitely a non-starter.
My mid-drive is at light enough to throw over a log but the Sur-Ron is in an uncomfortable position of being an overly heavy bicycle but an underpowered motorcycle.
I'm lucky in that I can ride miles of hard enduro and intermiate level trials from my back yard. I'd love an electric bike for quick afternoon play sessions, but this one just doesn't offer real motorcycle performance in stock form. Perhaps if a person comes from a bicycling background it feels powerful, but not if you are used to +55rwhp.

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Re: Sur-Ron - New Mid drive Bike

Post by freeflow » Dec 24 2018 6:49pm

That's correct they are self-threading, I use the cordless power drill just to screw them in (missing the English term).

The ones I have I have not seen online, bought them in a local shop but are similar to the ones in the link. I changed my tires since I'm pretty sure the thread is to long and will go thru the original tire. I used the 12mm. The new tire is heavier, 3,1 kilos instead of 2 kilos.

https://www.atvhuset.se/bronco-dubb-12m ... gLo6PD_BwE

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3DTOPO   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 6:55pm

Grantmac wrote:
Dec 24 2018 6:48pm
Sorry guys but not being able to making it up +18" steps and over logs means it won't work around here. So if it can't at least wheelie then it's definitely a non-starter.
My mid-drive is at light enough to throw over a log but the Sur-Ron is in an uncomfortable position of being an overly heavy bicycle but an underpowered motorcycle.
I'm lucky in that I can ride miles of hard enduro and intermiate level trials from my back yard. I'd love an electric bike for quick afternoon play sessions, but this one just doesn't offer real motorcycle performance in stock form. Perhaps if a person comes from a bicycling background it feels powerful, but not if you are used to +55rwhp.
It definitely can do wheelies at low speeds - no problem!



Have you actually rode one?

As for power, as I said, someone who grew up riding was ready to sell his 250cc to get a Sur Ron. He said, of course, it didn't have as much power, but was much more nimble and overall more fun to ride. And that is really what counts at the end of the day.

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Re: Sur-Ron - New Mid drive Bike

Post by Tommm » Dec 24 2018 7:29pm

All components could easily handle 6kw (battery is 6.6kw max in warm weather). Real power is about 4.2kw for normal and 4.5kw for X controller. The system is totally overbuilt. It would really help the power-to-weight ratio if they lifted the limit. Maybe a shunt mod on the controller is possible? Much easier than an aftermarket controller and battery.

There are two kind of shunt mods, tinning the shunt resistor wire(most low cost aftermarket controllers), or when the shunt resistor is an actual resistor on the board (bafang and more integrated controllers), in that case you have to replace it for a different resistor by soldering(ludicrous controller mod).

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Re: Sur-Ron - New Mid drive Bike

Post by Grantmac » Dec 24 2018 7:38pm

The only way I'd be able to ride one is to buy one and based on the reviews I'm far more likely to build a hotter mid-drive. It just doesn't perform well enough to replace my motorcycle and isn't able to go where I take my mid-drive.

6-8kw in a 110# package would be fun if the throttle delivery was punchy.

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Dec 24 2018 8:17pm

Grantmac wrote:
Dec 24 2018 7:38pm
The only way I'd be able to ride one is to buy one and based on the reviews I'm far more likely to build a hotter mid-drive.
Or I suppose you could travel somewhere to test ride it. ;)
Grantmac wrote:
Dec 24 2018 7:38pm
It just doesn't perform well enough to replace my motorcycle and isn't able to go where I take my mid-drive.
How do you know it isn't able to go where you go on your mid-drive?
Grantmac wrote:
Dec 24 2018 7:38pm
6-8kw in a 110# package would be fun if the throttle delivery was punchy.
Stock it peaks at 6KW.

Luna has hot-rodded one to run at 32KW. After over 100 pulls and doing over 100mph on a racetrack it finally burnt up. But I bet you could hot rod it to 12-16KW without the need to actively cool the motor.

And I would imagine that hot-rodding a Sur Ron would less work than building one - and probably less expensive too.

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