Sur-Ron - New Mid drive Bike

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Joachim   100 W

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Re: Sur-Ron - New Mid drive Bike

Post by Joachim » Aug 08 2018 3:20pm

a classic bike shop custom make these 240 sprockets T6 7075 aluminium 28th up to 65th.
They also machine the patern/holes.
https://www.jvmewparts.nl/c-4077056/420/

54/ 55th in combi 18s 19s battery and a sine wave controller 80Amps peak is something i wil like to do....
first try to kill the panasonic pf 16s 11p battery :mrgreen:

Also like to try an other brand chain,maby they are les noisy

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Rix   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Aug 08 2018 5:35pm

Joachim wrote:
Aug 08 2018 3:20pm
a classic bike shop custom make these 240 sprockets T6 7075 aluminium 28th up to 65th.
They also machine the patern/holes.
https://www.jvmewparts.nl/c-4077056/420/

54/ 55th in combi 18s 19s battery and a sine wave controller 80Amps peak is something i wil like to do....
first try to kill the panasonic pf 16s 11p battery :mrgreen:

Also like to try an other brand chain,maby they are les noisy
I am running a Renthal 420 Pitch MX chain, it doesn't stretch at all. Its not any quieter than the stock chain.

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motomoto   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Aug 08 2018 10:37pm

Because of Rix I did 10 each of a 55 tooth

Joachim   100 W

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Re: Sur-Ron - New Mid drive Bike

Post by Joachim » Aug 09 2018 1:50am

motomoto wrote:
Aug 08 2018 10:37pm
Because of Rix I did 10 each of a 55 tooth
please let me know you experience with the 55th.

The best thing on the sur-ron is the battery lcd % indicator :D the cells never drain down to real low voltage:lcd shows 21% total
battery voltage 56V/3.5V cell.i am sure these battery have a long life when never discharge lower like 15%.
I think they have designed the lcd state of charge indicator by watch to the point where the cell voltage sags under load....3.3V for the PF cells i think.

something i like to see for the sur-ron, decent allu/steel chain cover on the back and front sprockets,a broken chain can hit you in the back/legs.

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Rix   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Aug 09 2018 9:43am

motomoto wrote:
Aug 08 2018 10:37pm
Because of Rix I did 10 each of a 55 tooth
Are the available now? I guess i could just check your website.

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Re: Sur-Ron - New Mid drive Bike

Post by stonezone » Aug 10 2018 1:07am

Let me know when someone makes a 65 or even 70t sprocket. Want to get my splatter on!
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Rix   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Aug 10 2018 9:55am

stonezone wrote:
Aug 10 2018 1:07am
Let me know when someone makes a 65 or even 70t sprocket. Want to get my splatter on!
Moto Moto is cutting some 64T, Don't know how many he will have though. Don't know what your end goal is, but a sprocket that big will not allow your machine to draw max amps, you will have a lot of hill climbing range though. It will wheelie off the line like crazy too. :mrgreen:

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Allex   1 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Allex » Aug 10 2018 2:00pm

For a more silent drive train, would it not be better to change the stock sprocket to say 52 and increase the primary small sprocket with 4 more teeth? If you go even bigger like 58 rear and +10 in front we should gain even more silence(but space may be a problem). What do you guys think?

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Rix   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Aug 10 2018 4:15pm

Allex wrote:
Aug 10 2018 2:00pm
For a more silent drive train, would it not be better to change the stock sprocket to say 52 and increase the primary small sprocket with 4 more teeth? If you go even bigger like 58 rear and +10 in front we should gain even more silence(but space may be a problem). What do you guys think?
One could go to a 52T sprocket on the rear and a 13T (4:1 ratio)sprocket up front and have the exact gear ratio of a 48T to 12T witch is also 4:1 ratio. I don't know if it would be any more quieter though, but performance would be real close to identical. Going to a 58T on the rear and up 10T on front to a 22T sprocket would be a bad idea, these machines are powerful, but based on my experience, a secondary drive ratio of about 4.5 or 4.6 to 1 is optimal for a stock machine. With the 58T and 22T combo, that would reduce the secondary drive ratio to 2.6:1, way to tall of gearing and loss of mechanical leverage for our machines. Or even a 52T and a 16T combo would come out to a 3.25:1 ratio on the secondary which is still much taller than the stock 4:1 ratio. Running that maybe quieter though as the motor would not be able to spin as many RPMs as can the stock ratio due to loss of mechanical advantage.

///Edit/// Primary change to secondary, Freudian slip
Last edited by Rix on Aug 10 2018 11:00pm, edited 1 time in total.

Joachim   100 W

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Re: Sur-Ron - New Mid drive Bike

Post by Joachim » Aug 10 2018 4:51pm

a strong belt is the only way to make the sur ron silent,for offroad you can make the belt drive train close in a belt case?

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Re: Sur-Ron - New Mid drive Bike

Post by Tommm » Aug 10 2018 5:04pm

Joachim wrote:
Aug 10 2018 4:51pm
a strong belt is the only way to make the sur ron silent,for offroad you can make the belt drive train close in a belt case?
Already has a belt from motor to sprocket.
Image

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madin88   100 MW

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Re: Sur-Ron - New Mid drive Bike

Post by madin88 » Aug 11 2018 5:09am

Rix wrote:
Aug 10 2018 4:15pm
One could go to a 52T sprocket on the rear and a 13T (4:1 ratio)sprocket up front and have the exact gear ratio of a 48T to 12T witch is also 4:1 ratio. I don't know if it would be any more quieter though, but performance would be real close to identical.
Thats how it is. The larger the small drive sprockets the lower the noise will be (and wear).
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Allex   1 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Allex » Aug 11 2018 8:46am

Ok, maybe a task for motormoto to see how big up front we can fit and then he could make them :)

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Re: Sur-Ron - New Mid drive Bike

Post by lightbeer81 » Aug 14 2018 4:10pm

Uran93 wrote:
Jul 25 2018 12:17pm
lightbeer81 wrote:
Jul 24 2018 2:23am
Had my Sur-Ron bike for a few weeks now and done about 250km on it. Have a tear and in the rear brake hose and need to replace it. Visited a local MTB bike shop here focused mainly on Shimano and showed them the brake, but they say they didn't know what parts would fit etc. (probably to much to do this season and not super interested in more work). Next time I like to be more specific in what I need. So if anyone here could provide me with some more precise instructions that would be great.
Read in this thread that someone recommended MT5 Magura for replacement but I think the original brake was doing the job fine so far and would prefer just new hose (and oil I guess).

Overall I really like the bike and it runs really well both on and off road. Perfect for a newbie like myself which mainly has 80cc experience. What maintenance do you guys recommend and how often?
You can use Shimano BH90 hose kit. Easy to find on Amazon. But I personally replaced front brakes and will replace rear, cause both front and rear are leaking. Original brakes are very low quality copy from Shimano XT 9000 I guess. They have 4 piston calipers, but they (pistons) are leaking.
If you replace them you need to keep original levers, cause they have engine breaker.

I replaced my front brakes to Shimano Zee, but I keep original lever, it’s not bad quality and you need it to have engine breaker.

You can find a lot of YouTube videos how to replace and tune and pump your brakes, easy to do it and learn something new for you.

Shimano Zee fit perfectly and it is amazing 4 carbon piston set, great calibration and sensitivity, you can read some reviews.

Let me know if you have any questions.
Thanks for the detailed tips. I have ordered a new Shimano Zee brake for the rear and will replace the front as well if the feel is a lot better! Will get back with results...

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Re: Sur-Ron - New Mid drive Bike

Post by Uran93 » Aug 15 2018 10:03am

[/quote]
Last edited by Uran93 on Aug 15 2018 10:05am, edited 1 time in total.

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Re: Sur-Ron - New Mid drive Bike

Post by Uran93 » Aug 15 2018 10:04am

lightbeer81 wrote:
Aug 14 2018 4:10pm
Uran93 wrote:
Jul 25 2018 12:17pm
lightbeer81 wrote:
Jul 24 2018 2:23am
Had my Sur-Ron bike for a few weeks now and done about 250km on it. Have a tear and in the rear brake hose and need to replace it. Visited a local MTB bike shop here focused mainly on Shimano and showed them the brake, but they say they didn't know what parts would fit etc. (probably to much to do this season and not super interested in more work). Next time I like to be more specific in what I need. So if anyone here could provide me with some more precise instructions that would be great.
Read in this thread that someone recommended MT5 Magura for replacement but I think the original brake was doing the job fine so far and would prefer just new hose (and oil I guess).

Overall I really like the bike and it runs really well both on and off road. Perfect for a newbie like myself which mainly has 80cc experience. What maintenance do you guys recommend and how often?
You can use Shimano BH90 hose kit. Easy to find on Amazon. But I personally replaced front brakes and will replace rear, cause both front and rear are leaking. Original brakes are very low quality copy from Shimano XT 9000 I guess. They have 4 piston calipers, but they (pistons) are leaking.
If you replace them you need to keep original levers, cause they have engine breaker.

I replaced my front brakes to Shimano Zee, but I keep original lever, it’s not bad quality and you need it to have engine breaker.

You can find a lot of YouTube videos how to replace and tune and pump your brakes, easy to do it and learn something new for you.

Shimano Zee fit perfectly and it is amazing 4 carbon piston set, great calibration and sensitivity, you can read some reviews.

Let me know if you have any questions.
Thanks for the detailed tips. I have ordered a new Shimano Zee brake for the rear and will replace the front as well if the feel is a lot better! Will get back with results...
Don't forget - Zee has a different type of hose joints, compare to original Sur-ron brakes. It's called "banjo" connection. So, it is better/cheaper to buy "caliper + hose", cause original Sur-Ron joint won't work for Zee caliper.

Just in case - https://www.amazon.com/gp/product/B007Y ... UTF8&psc=1

socalsurron   1 µW

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Re: Sur-Ron - New Mid drive Bike

Post by socalsurron » Aug 15 2018 1:37pm

Bought a pair of the Sur Ron's through Luna. Overall, awesomely fun machines. However, I'm at about 100 miles on each and have a couple of concerns.

One bike had a controller fail, which was then replaced by Luna under warranty (I'm in SoCal, fortunately close enough to drop by the shop locally). There was no indication as to the cause - it simply failed during normal use, resulting in a dead bike on a hot, dry trail. No other components were affected from what I can tell. I guess this is only one of a couple failures they've seen thus far, so maybe I was just one of the lucky ones. Hopefully the new "x" controller will resolve any other issues with this version.

The other issue I've been having is with the poor quality pedal kits (Luna's, not Sur Ron's). Not only are the cranks very iffy - the finish is already flaking and corroding - but the spindle bearings are extremely poor and both bikes have a TON of chain "wander" as it winds around the pedal sprocket - 1-2mm each direction on the worst one. This is causing a lot of extra chain noise, and both the sprocket and chain are already showing appreciable wear as a result.

Wanted to raise these issues here to see if anyone else has had similar experiences. I'm going to touch base with Luna directly to see if the pedal kit issues have become common (I assume they are).

lightbeer81   10 µW

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Re: Sur-Ron - New Mid drive Bike

Post by lightbeer81 » Aug 16 2018 3:07am

Uran93 wrote:
Aug 15 2018 10:04am
lightbeer81 wrote:
Aug 14 2018 4:10pm
Uran93 wrote:
Jul 25 2018 12:17pm
lightbeer81 wrote:
Jul 24 2018 2:23am
Had my Sur-Ron bike for a few weeks now and done about 250km on it. Have a tear and in the rear brake hose and need to replace it. Visited a local MTB bike shop here focused mainly on Shimano and showed them the brake, but they say they didn't know what parts would fit etc. (probably to much to do this season and not super interested in more work). Next time I like to be more specific in what I need. So if anyone here could provide me with some more precise instructions that would be great.
Read in this thread that someone recommended MT5 Magura for replacement but I think the original brake was doing the job fine so far and would prefer just new hose (and oil I guess).

Overall I really like the bike and it runs really well both on and off road. Perfect for a newbie like myself which mainly has 80cc experience. What maintenance do you guys recommend and how often?
You can use Shimano BH90 hose kit. Easy to find on Amazon. But I personally replaced front brakes and will replace rear, cause both front and rear are leaking. Original brakes are very low quality copy from Shimano XT 9000 I guess. They have 4 piston calipers, but they (pistons) are leaking.
If you replace them you need to keep original levers, cause they have engine breaker.

I replaced my front brakes to Shimano Zee, but I keep original lever, it’s not bad quality and you need it to have engine breaker.

You can find a lot of YouTube videos how to replace and tune and pump your brakes, easy to do it and learn something new for you.

Shimano Zee fit perfectly and it is amazing 4 carbon piston set, great calibration and sensitivity, you can read some reviews.

Let me know if you have any questions.
Thanks for the detailed tips. I have ordered a new Shimano Zee brake for the rear and will replace the front as well if the feel is a lot better! Will get back with results...
Don't forget - Zee has a different type of hose joints, compare to original Sur-ron brakes. It's called "banjo" connection. So, it is better/cheaper to buy "caliper + hose", cause original Sur-Ron joint won't work for Zee caliper.

Just in case - https://www.amazon.com/gp/product/B007Y ... UTF8&psc=1
I ordered a kit with hose, caliper and lever. It was cheaper then just ordering caliper + hose. But the hose part of the kit should be the same as the link you provided I guess. This is what I ordered:
https://www.bikeinn.com/bike/shimano-ze ... 35997232/p
Is it ok? Thanks again.

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Aug 16 2018 10:14am

socalsurron wrote:
Aug 15 2018 1:37pm
Bought a pair of the Sur Ron's through Luna. Overall, awesomely fun machines. However, I'm at about 100 miles on each and have a couple of concerns.

One bike had a controller fail, which was then replaced by Luna under warranty (I'm in SoCal, fortunately close enough to drop by the shop locally). There was no indication as to the cause - it simply failed during normal use, resulting in a dead bike on a hot, dry trail. No other components were affected from what I can tell. I guess this is only one of a couple failures they've seen thus far, so maybe I was just one of the lucky ones. Hopefully the new "x" controller will resolve any other issues with this version.

The other issue I've been having is with the poor quality pedal kits (Luna's, not Sur Ron's). Not only are the cranks very iffy - the finish is already flaking and corroding - but the spindle bearings are extremely poor and both bikes have a TON of chain "wander" as it winds around the pedal sprocket - 1-2mm each direction on the worst one. This is causing a lot of extra chain noise, and both the sprocket and chain are already showing appreciable wear as a result.
That's the first controller failure I've heard of. It would be interesting to know what exactly failed.

The pedal kit is crap and even if it was well made, it would still be crap due to the way it engages the chain. In CA you can apparently register it as a moped and not need pedals to be street legal. The pedals might be more useful if they drove the jack shaft somehow but this would require some kind of freewheel clutch on the jack shaft and another sprocket there. Not easy.
"One test is worth a thousand opinions"

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Re: Sur-Ron - New Mid drive Bike

Post by macribs » Aug 16 2018 10:41am

The whole pedal project was one huge fail in my eyes. They even managed to remove some of the original torque while they where at it. Terrible. Like you say a jackshaft + freewheel is the way to go for those who need pedals. Remember the motoped? They had prototype of an electric edition, with a clever jackshaft solution. Maybe look there for inspiration and try to incorporate their thoughts to the Sur Ron? Or, get a license plate and loose the pedal.

Any new info in the street legal EU moped 45 km/h version? Is there a date for release?

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motomoto   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Aug 16 2018 11:56am

I am working on a pedal kit. It runs a generator that charges the battery.

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Re: Sur-Ron - New Mid drive Bike

Post by Dext3r » Aug 16 2018 12:38pm


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Re: Sur-Ron - New Mid drive Bike

Post by macribs » Aug 16 2018 12:56pm

Yeah a month ago or so EU too put taxes on china e-bikes. Sucks.

Gotta hate on them politicians. They show incredible skills when it comes to fcuk the common guy, but if some new thoughts are required to solve serious problems or find funds to new infrastructure their mental capacity is on par with small children.

Maybe we should propose everyone to spread some hate on their congressman? Write them a letter and let them know they are major fcuk ups and people are watching and keeping score. Call them up during office hours and let them have it. Post on their face or find their email and tell them to clean up their act. Then work you way upwards til you reach the man on the top, and while you're at it give that man a shaver and tell him to take care of himself, the pride and joy that once was a set of hair is ridiculous, hm great I managed to close on a personal attack, just like the man himself.

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fechter   100 GW

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Re: Sur-Ron - New Mid drive Bike

Post by fechter » Aug 16 2018 3:40pm

motomoto wrote:
Aug 16 2018 11:56am
I am working on a pedal kit. It runs a generator that charges the battery.
That sounds a bit more practical but not sure if it would meet the legal requirements everywhere. Wording varies a lot on these regulations. For USA federal definition, it says "fully operable pedals". In some it just says the motor can't run unless you are pedaling. In this case, the pedals only have to interface to the controller and not really supply any power.

It is unlikely you could make it run by pedal power alone, but this seems to be unnecessary in most cases.

A pedal generator would be much more flexible in the mounting and not screw up the gearing or chain line.
"One test is worth a thousand opinions"

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Allex   1 GW

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Re: Sur-Ron - New Mid drive Bike

Post by Allex » Aug 16 2018 3:57pm

We will have our first EU versions end of Sept. here in Sweden.

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