Sur-Ron - New Mid drive Bike

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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Sep 16 2020 12:51pm

Offroader wrote:
Sep 04 2020 12:25pm
The question is, what would I improve on the bike with a new model?

I think the only thing I can think to improve is designing the frame and geometry around 27.5" forks and 19" motorcycle tires.

Unfortunately you can't get quality 26" forks anymore as they are obsolete, everything is 27.5 and 29". I was lucky enough to have bought the last of the 26" fox forks.

Yes, I know you can throw a 27.5" fork on the bike but from my extensive research in downhill biking forums and asking many people on the forums who race downhill bikes, it is not recommended and not a good idea to do this as you will most likely change the geometry for the worst. I like the fact that sur-ron handles like a motorcycle at 50MPH and like a mountain bike at 15 MPH.

I do know many guys use 27.5" forks but I don't think they are pushing the bike extremely hard off-road and are not as sensitive as I am to the handling.

That being all said, just design the bike to come with a 27.5" fork this way we have decent fork selections and don't have to use the wrong size just to put a high quality fork on the bike. I don't want to be stuck with cheap 26" fork selections.
we all know your "beat to death" offroad stories but all we see is cruising some flat stairs. :roll:

i wouldnt say anything but if someone reads that diarrhea i have to tell you:

your 26" Fork research is completley B U L L S H I T

talking about geometry with a bigger rear as front....thats total my humour.

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Re: Sur-Ron - New Mid drive Bike

Post by Tommm » Sep 16 2020 1:27pm

Merlin wrote:
Sep 16 2020 12:51pm
we all know your "beat to death" offroad stories but all we see is cruising some flat stairs. :roll:

i wouldnt say anything but if someone reads that diarrhea i have to tell you:

your 26" Fork research is completley B U L L S H I T

talking about geometry with a bigger rear as front....thats total my humour.
I am not sure how it is even possible to get that worked up on a post of a guy just writing his experiences... :lol:

If it will mess up the geo depends on one thing. Actually measuring the head angle and comparing it to other light dirt bikes. If 27 fork brings it closer to mainstream = better, if 26 is closer = better.

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Re: Sur-Ron - New Mid drive Bike

Post by Kauaiguy » Sep 16 2020 3:38pm

I’m running the Fox40 27,you get much better tire clearance from the hoop.I’m pretty sure Surron now come with Dnm 27’s as the 26 are no longer being made. My handling is much better than the 26 inch Rst they replaced🤔,going down hills feels much safer as the Fox40 stays higher in the stroke.I don’t ride stairs ,only A trails,mud,rocks and jungle.

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Re: Sur-Ron - New Mid drive Bike

Post by crazy_dave » Sep 21 2020 6:37am

I cannot get this damn battery lid to open (lock is broken with battery inside).
I see two ways I can go about it, 1) Remove the rear seat section ( looks like a PITA) and go at it from the backside. 2) find a way to remove the battery door front pivot pins and go at it from the front.
Does anyone know how to get those front pivot pins out? They are not threaded and I do not see any clips. The pins will spin and there is a little lateral movement but I don’t see how they are locked in.
It’s better to apologize than it is to ask permission.

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Allex   1 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Allex » Sep 21 2020 7:09am

crazy_dave wrote:
Sep 21 2020 6:37am
I cannot get this damn battery lid to open (lock is broken with battery inside).
I see two ways I can go about it, 1) Remove the rear seat section ( looks like a PITA) and go at it from the backside. 2) find a way to remove the battery door front pivot pins and go at it from the front.
Does anyone know how to get those front pivot pins out? They are not threaded and I do not see any clips. The pins will spin and there is a little lateral movement but I don’t see how they are locked in.
I would drill a hole in this screw then take a torx bit, hit that in the hole and unscrew.
front pivot pins are held by e-clips under the lid so this could be a way out for you, use long pliers or screwdriver to get to them. you will see the left one you look under the lid from the charge port side.
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crazy_dave   10 mW

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Re: Sur-Ron - New Mid drive Bike

Post by crazy_dave » Sep 21 2020 7:29am

AH-HA, behold the third solution! I did not think to look under that sticker, TY!
I would imagine that bolt is relatively short. Is it just holding the locking bracket in place?
I will take a look when I get home and see which option offers the path of least resistance.
Thank you again!
It’s better to apologize than it is to ask permission.

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Re: Sur-Ron - New Mid drive Bike

Post by ebikeguy123 » Sep 24 2020 2:15am

Feedback. Battery is Sony VTC6 pack. www.teznic.com for more info.
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thoroughbred   100 W

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Re: Sur-Ron - New Mid drive Bike

Post by thoroughbred » Sep 24 2020 6:35am

ebikeguy, some pretty interesting ideas there. I may have missed it but what is your affiliation with Teznic?

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Sep 24 2020 9:29am

XT150 connectors are horrible. Very hard to plug and unplug, at least the ones I have.
"One test is worth a thousand opinions"

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ggHawk   1 mW

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Re: Sur-Ron - New Mid drive Bike

Post by ggHawk » Sep 26 2020 7:33pm

Hey guys. I've been following this thread for a while. I bought a Surron this spring, and have been slowly upgrading it. Thanks to many of you for info that was helpful. I've been planning on posting my mods when I finally finished them. Took forever for various reasons I can explain later. I barely finished before the riding vacation I'm on right now in Ouray, Colorado. I've got a problem that maybe someone can help with.
Background: I have a BAC8000 controller from Teznic. I've disconnected/removed all the cut off sensors (stand/brake/tip). I use the stock battery, a LiteSpeed 72V battery, and a 72V custom battery I designed/built that goes under the rear seat - more on that later.
Problem: The power cuts out completely and immediately with full throttle. Works great up to about 1/2 - 3/4 throttle. The BACdoor app reports no faults when this happens. Backing off for a few seconds is all it takes to recover. I'm using the stock throttle. I tried changing the "throttle full voltage setting" (via BACdoor) to a higher setting. No change in behavior. I get the same problem with any of the batteries, so it's very unlikely a BMS problem.
Tom at Teznic has been trying to help. Actually, before this, I had a similar cut out problem that happened with full throttle for several seconds. He solved that problem by sending a new parameter set which I loaded with BACdoor - actually he sent several such files, but eventually he got two that worked (one for the 60V and one for the 72V). Before I left, the bike was working fine on the street. Now, loading the same parameter sets in, it has the current immediate cut out problem. It doesn't seem to matter what the SOC (state of charge) of the batteries are. Any ideas?
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Merlin   10 MW

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Re: Sur-Ron - New Mid drive Bike

Post by Merlin » Sep 26 2020 8:29pm

What bms is installed? How is the bac configured?
Can you upload your file?

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ggHawk   1 mW

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Re: Sur-Ron - New Mid drive Bike

Post by ggHawk » Sep 26 2020 10:03pm

Thanks Merlin.
The BMS in the pack that I built is ANT. Apparently the LiteSpeed pack is also ANT because my VBMS app connects to it. I don't know what's in the stock battery, but like I said I don't suspect the BMS since they all behave the same.
I've attached a version of the 72V file that Tom sent me that I reformatted to be shorter, easier to read, and with descriptions. Also, it's after a motor calibration that he had me do. It was not his normal 72V file. Apparently, it got corrupted. This is just something he came up with trying to help me quickly. He's supposedly going to ASI this week to recover it or somehow find a solution, but I doubt he'll have anything until at least Tues or Wed. I'm leaving Thu, so I thought I'd give ES a shot.
If anyone has a known good 72V (or even 60V) file for a BAC8000 on a surron, an upload would be very nice.
Also in going back through the files to upload one here, I just realized a mistake I made. I'll try it in the morning.
Last edited by ggHawk on Sep 27 2020 11:09am, edited 1 time in total.

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Re: Sur-Ron - New Mid drive Bike

Post by ggHawk » Sep 27 2020 9:54am

I thought maybe I had loaded the wrong program before, but I just double checked it, and it still has the cut out. Today I'll probably try a different throttle.

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Re: Sur-Ron - New Mid drive Bike

Post by ggHawk » Sep 27 2020 11:27am

Swapped to the throttle that Teznic provided. Now it faults with "Throttle voltage out of range". I tried backing down the "throttle off voltage" setting a little bit at a time, until I got all the way down to 0. Still says out of range (I saved to flash and power cycled after each change). Oh well, at least it runs. I'll ride it as it is until another idea surfaces from somewhere.

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Re: Sur-Ron - New Mid drive Bike

Post by ggHawk » Sep 28 2020 3:08pm

I put it on a stand and read the throttle voltage from BACdoor (which I finally found you could do), it showed the full value at 5.54V! Apparently it's being given more than the 5V ASI says it's given (I had previously tried 4.9). Anyway, changing the full voltage setting to 5.6 fixed the problem.

dirkdiggler   10 kW

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Re: Sur-Ron - New Mid drive Bike

Post by dirkdiggler » Oct 01 2020 3:35pm

Saw this over at alta forum about the Storm bee being released. Has some pictures and info.
https://altaownersforum.com/threads/the ... -out.1895/
Not really out yet, but seems like it might come out sometime. Still a year behind schedule. The minute I order the 2nd light bee, it'll be released for real. :roll:

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X-Nitro   1 W

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Re: Sur-Ron - New Mid drive Bike

Post by X-Nitro » Oct 01 2020 5:05pm

New H-D rear suspension triangle link now available from Prickly Motorsports,
https://www.pricklymotorsports.com/shop ... 4g84l2571v
They also make foot peg re-locators for those of you who are too big for the bike.
:shock: 48v 1500w Custom 1/2 fatty bannaseat hardtail hub streetbike - The modern electric "stingray" mullet bike :bolt: E-Goat Sur-Ron

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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 » Oct 01 2020 6:00pm

dirkdiggler wrote:
Oct 01 2020 3:35pm
Saw this over at alta forum about the Storm bee being released. Has some pictures and info.
https://altaownersforum.com/threads/the ... -out.1895/
Not really out yet, but seems like it might come out sometime. Still a year behind schedule. The minute I order the 2nd light bee, it'll be released for real. :roll:
couple ppl in eu now have storm from their local dealer, containers on the way.. video on YouTube..
some ride & sk8 videos:
metacafe.com/channels/NATAS666DAMIEN
http://www.youtube.com/natas666damien
i have nothing for sale.. :)

dirkdiggler   10 kW

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Re: Sur-Ron - New Mid drive Bike

Post by dirkdiggler » Oct 01 2020 11:21pm

Links please!
Only storm bee you tube video I see is from the crazy Russian hacker. Problem it's in russian and 1hr long!
Big question is did they ever release a price?

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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 » Oct 02 2020 12:05am

where are you located, usa?? bc luna has no intention to import storm to usa..

phasebook reference:
https://m.facebook.com/groups/785457324 ... 4653551661
some ride & sk8 videos:
metacafe.com/channels/NATAS666DAMIEN
http://www.youtube.com/natas666damien
i have nothing for sale.. :)

dirkdiggler   10 kW

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Re: Sur-Ron - New Mid drive Bike

Post by dirkdiggler » Oct 02 2020 10:33am

I'm in the u.s. Someone posted that luna wasn't going to sell the storm bee in the alta forum. Might have to ask for dealership rights? What else can Americans do to get this?
I watched most of the Russian video. Looks pretty good. Four year old Alta bikes are selling for $10k used here in the states. As long as pricing is around that, they should sell really well.

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sens_dep   1 mW

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Re: Sur-Ron - New Mid drive Bike

Post by sens_dep » Oct 03 2020 3:13pm

Does anyone sell battery cases that are a tiny bit taller? I’ve got my 72v battery pretty much done, but this case for the original one doesn’t quite fit. I know I can raise the lid on the bike up to fit a larger case... but I’m struggling to figure out how to fabricate one.

Ideas? Vendors?

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Re: Sur-Ron - New Mid drive Bike

Post by Hawaiiguy » Oct 03 2020 6:59pm

How much to short?If only a inch or two you could take the stock lid as a template and make spacers cut from plastic cutting board as an example.

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ggHawk   1 mW

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Re: Sur-Ron - New Mid drive Bike

Post by ggHawk » Oct 06 2020 11:24am

Hey guys. I said I’d post about the mods on my surron. For now, I won’t get too detailed. If someone wants more, just ask.
Original bike: from Lunacycle took about 4 weeks (April).
ASI BAC8000 controller: Acquisition of this was long and painful. Originally ordered from ERT, but apparently Alan was sick, so it took forever to receive (3 months). It was DOA. It was taking too long for him to replace or even respond to emails, so I got a CC refund and moved on to Teznic. They supposedly had stock, but were also slow (about 5 weeks to receive), and the loaded parameter set wasn’t right. At least Tom at Teznic responded to emails, and tried helping me. He made progress, but my posts last week described that resolution.
72V Litespeed battery: 200 Sony VTC6 cells give much more power, and better range.
Wheels/Tires: The biggest problem on my early rides (in the Colorado mountains) was traction. My favorite tire type has been the “cheater” – soft Trials rubber with moto style tread pattern. I couldn’t find any for 19” wheels, so I decided to downsize the rear wheel to 16” which gives many more options since that’s the common size for the small dirt bike class. Tires for this class are smaller and lighter than full size dirt bike rear tires (which wouldn’t fit anyway). But because the aspect ratios are much taller, it only lowers the rear end by less than 3/8”, which I actually like since I’m short (5’7”) and prefer a slightly more leaned back geometry. I had a custom 16” wheel built, and mounted a Shinko 525 Cheater tire. Even this was slightly too wide (4”), so I shaved the side knobs somewhat – see pics. I kept the front wheel stock and mounted a Shinko 520 – softest I could find with my preferred balanced tread pattern. Traction was much better, which was especially needed with the extra power. They also helped significantly with the harsh ride because I can run them at 10 lbs (I use Motion Pro Liteloc rim locks).
sronTireShave.jpg
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Seat: The stock one wasn’t as bad as I’d heard, but it definitely needed to be more cushy for my bony butt, so I added 2” of foam covered with tough outdoor fabric I had left over from my pickup “SoftTopper”. See pics.
Suspension: Since I’m less than 140 lbs and don’t do big jumps, the stock suspension is good enough so far… although it’s pretty harsh on the trail, which may eventually force an upgrade.
Brakes: So far the stock ones are working well enough for my light weight, but I’ll eventually upgrade at least the pads.
Allex’s belt drive (52T equivalent gearing): The Gates belt on my Zero FX has lasted 6 years (2500 miles, many of which in the dirt) with no problems. I really like the quiet, clean, efficient operation. The only maintenance is to check the tension from time to time with the very cool audio frequency app.
https://ridesurron.se/en/tillbehor/belt-kit
HDPE bash plate:
https://racespecsurron.com/bash-plate-guard-sur-ron/
Bark busters (hand guards):
https://www.amazon.com/gp/product/B07XB ... UTF8&psc=1
Handlebar control switch:
https://www.amazon.com/gp/product/B0039 ... UTF8&psc=1
Rear Brake/Running/Turn Signal LEDs:
https://www.amazon.com/gp/product/B01GJ ... UTF8&psc=1
Front Running / Turn Signal LEDs:
https://www.amazon.com/gp/product/B01L8 ... UTF8&psc=1
Flasher Relay:
https://www.amazon.com/gp/product/B073J ... UTF8&psc=1
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Rear fender: Modified to fit my custom rear bracket assembly. That bracket turned out to be not strong enough to hold the battery, so I ended up removing it on this trip and just strapping it to the seat frame. I'll remake a stronger bracket later.
https://www.amazon.com/gp/product/B075G ... UTF8&psc=1
Tank Bag: This bag is about the perfect size for the surron. The included straps work great.
https://www.amazon.com/gp/product/B084B ... UTF8&psc=1
Extra battery: Since range is such a big problem, I decided to add a pack. I figured since I was a EE in my previous life, I should be able to do it. I read that some people carry “reserve” batteries in a back pack. Others mount one on top of the main pack. Others (e.g. Fechter) use saddle bags. I decided to utilize the available space under the seat to keep the dimensions of the bike tight and the C.G. as low as possible (it also looks better). By designing and printing a plastic enclosure to go there, I was able to fit 140 cells. I printed in PETG since ABS warps too much at this dimension, and PLA won’t hold its shape with the anticipated temperatures. It mounts using longer versions of the two bottom seat mount screws and two screws through a custom rear bracket into heat inserted nuts in the shell. See pics.
I used a kWeld spot welder for the cell interconnects using .15mm nickel strips on top of .2mm copper sheet segments to minimize IR losses. I had to punch slots in the copper to facilitate good welds.
The configuration is 20s7p using Sony VTC5D which I chose because I wanted to have at least as much current capacity at 7p as the LightSpeed pack has at 10p.
For the time being, the two halves of the shell are just taped together with water proof Gaffers tape. Eventually, I’ll glue it together with 3D Gloop for PET, which I’ve tested on this specific PETG. Some PET compounds aren’t compatible with this glue, but this one is – from “IC3D”.
Honeycomb Cell holders:
https://www.ebay.com/itm/18650-Honeycom ... 2749.l2649
kWeld spot welder: Keith shipped it to me very fast. I used a car battery for the supply. Worked great. After experimentation, I ended up setting it to 95 joules.
https://18650shrinkandcellholders.com/kWeldPricing
18650shrink@gmail.com
Nickel Strip: .15mm x 10mm. I actually cut it into 5mm strips on each side of the copper slots, to maximize the weld current going through the battery caps.
https://www.amazon.com/gp/product/B07WB ... UTF8&psc=1
Copper Sheet: .2mm thick. Cut to connect adjacent 7p groups, with slots cut per cell. See pics.
https://www.amazon.com/gp/product/B07ZC ... UTF8&psc=1
BMS: This one has a 400A rating, so it minimizes losses so I can have protection and not bypass the discharge path.
https://www.ebay.com/itm/Smart-Lifepo4- ... SwMYxfD~bt
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That’s about it.
Riding this bike is so much easier than my Zero in very rough conditions because I can reach the ground with both heals and it’s so light. Even though my upgrades added a fair amount of weight (25-30 lbs), I can still pick it up over obstacles when necessary. It’s still about half of the Zero weight.
The stock bike was way too wimpy on the street for me (I’m used to the 44HP, 70 ft-lbs, of the Zero), but in the dirt, the stock bike wasn’t too bad. The Zero is way overkill there. With the BAC8000 and 72V high current packs, this surron is now good enough on the street, and can climb anything its tires can manage offroad.
Range is the only real issue now. Even with my extra pack, it’s not enough. What I have to do is ride in the morning to a destination, which sometimes requires some of the extra pack. Meet the wives for lunch at that destination, who drove there with my other main pack (60V stock). After swapping, I can ride back. I could always build another extra pack to swap in the same way if necessary, but it would be much better if we just have one more factor of 2 improvement in battery energy density. Someday…
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Last edited by ggHawk on Oct 06 2020 5:31pm, edited 1 time in total.

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Oct 06 2020 2:28pm

Nice work. Thanks for posting the pictures.

I never would have thought to put an extra battery under the seat frame. Looks like a great battery build and a lot of work.
I'd love to get a smaller rear rim so I could get a better selection of tires.

What's your top speed?
"One test is worth a thousand opinions"

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