Sur-Ron - New Mid drive Bike

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PRW   10 kW

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Re: Sur-Ron - New Mid drive Bike

Post by PRW » Oct 19 2018 2:54pm

looking at the AJP PR3 - it has a seat height of only 33 inches. In that case, what height is the Sur-Ron's seat?

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Re: Sur-Ron - New Mid drive Bike

Post by aspencreek » Oct 19 2018 3:32pm

Antenor wrote:
Oct 19 2018 2:41pm
Your pr3 is smaller than mine...do you have the stock wheels or bigger?

Know i have a notion of surron size...is really small
PRW wrote:
Oct 19 2018 2:54pm
looking at the AJP PR3 - it has a seat height of only 33 inches. In that case, what height is the Sur-Ron's seat?
Yeah, the Sur Ron was a bit smaller than I thought it would be, but not bad at all. 3DMOTO is taller than me (I'm 5'7") and had no problems on it. He has riser bars which helps when standing, but the peg to seat ratio didn't feel cramped to me like some littler dirt bikes.

My AJP has a seat height of 34" and it has 17" back / 19" front tires. The specs list 33" seat I believe, but that's with a lowering link installed that I don't have. The Sur Ron was a little lower. I think they list it as 32" seat height which seemed about right. So if you know dirt bikes, the size of the AJP I have is about the same as a Honda CRF230 or the Kawasaki KLX140G. The Sur Ron is about the size of a Yamaha TTR125L or a Kawasaki 140L, but with a less cramped cockpit. I didn't ride it super long or go too crazy with it (borrowed bike, gotta be careful) so it's hard for me to say exactly how the power compares, but felt similar to the TTR125, although without having to shift up through a gear box it got up to speed quicker I'd say. Enough for plenty of fun!

Hopefully this sizing stuff is helpful - not trying to sidetrack the thread too off topic!

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Re: Sur-Ron - New Mid drive Bike

Post by Antenor » Oct 19 2018 3:43pm

Very helpful, thanks :)

Since i have electric bikes i dont apreciate the way i did the gas motor sound...e fell more relaxed and connected to nature without noise...its shame that in portugal nobody is selling surron.

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Re: Sur-Ron - New Mid drive Bike

Post by n2mb » Oct 19 2018 4:20pm

Antenor wrote:
Oct 19 2018 3:43pm
Since i have electric bikes i dont apreciate the way i did the gas motor sound...e fell more relaxed and connected to nature without noise...its shame that in portugal nobody is selling surron.
That's funny. Coming from a direct drive E-bike with a sine wave controller, the Sur Ron seems loud to me! I don't have a the X controller, so maybe it gets quieter with that upgrade.

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Re: Sur-Ron - New Mid drive Bike

Post by Allex » Oct 19 2018 4:33pm

n2mb wrote:
Oct 19 2018 4:20pm
Antenor wrote:
Oct 19 2018 3:43pm
Since i have electric bikes i dont apreciate the way i did the gas motor sound...e fell more relaxed and connected to nature without noise...its shame that in portugal nobody is selling surron.
That's funny. Coming from a direct drive E-bike with a sine wave controller, the Sur Ron seems loud to me! I don't have a the X controller, so maybe it gets quieter with that upgrade.
Not really! But with the belt it will. NOW... who want some belts on this thing?!

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Re: Sur-Ron - New Mid drive Bike

Post by n2mb » Oct 19 2018 4:49pm

Allex wrote:
Oct 19 2018 4:33pm
n2mb wrote:
Oct 19 2018 4:20pm
Antenor wrote:
Oct 19 2018 3:43pm
Since i have electric bikes i dont apreciate the way i did the gas motor sound...e fell more relaxed and connected to nature without noise...its shame that in portugal nobody is selling surron.
That's funny. Coming from a direct drive E-bike with a sine wave controller, the Sur Ron seems loud to me! I don't have a the X controller, so maybe it gets quieter with that upgrade.
Not really! But with the belt it will. NOW... who want some belts on this thing?!
sounds good to me! no grease and less maintenance?

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Oct 19 2018 5:28pm

aspencreek wrote:
Oct 19 2018 12:37pm
That is true. Went up there yesterday afternoon and met up with 3DTOPO to have a look at his Sur Ron and do some trail riding.
It was nice to meet you and I had fun geeking out and on the ride.

n2mb wrote:
Oct 19 2018 4:20pm
That's funny. Coming from a direct drive E-bike with a sine wave controller, the Sur Ron seems loud to me! I don't have a the X controller, so maybe it gets quieter with that upgrade.
It's definitely about 50% more quiet from the X controller. But I think when I switched my chain to a well lubricated gold chain it made an even bigger difference (probably had more to do with being packed with grease than anything). I think the 420 chain is just much more beefy than a bike chain is considerably louder.

Allex wrote:
Oct 19 2018 4:33pm
Not really! But with the belt it will. NOW... who want some belts on this thing?!
I would gladly order a kit.

n2mb wrote:
Oct 19 2018 4:49pm
sounds good to me! no grease and less maintenance?
A Belt drive is practically silent in comparison to a chain drive, and yeah pretty much maintenance free.

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motomoto   1 kW

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Oct 19 2018 10:39pm

Sounds like I need to finish the belt drive I have wanted to do since I got the production bike back in December. It was quiet compared
to the noisy test bike and all I mostly heard was the chain hitting the countershaft sprocket.

I might do something weird with the rear pulley to make it easy to machine like skip every other tooth. The rear sprocket will still have
way more teeth engaged than the front. The pulley stock I have for the front pulley is 32 tooth 8mm GT2 for Gates Poly Chain GT Carbon. The belt will be 12mm width. It should be really quiet compared to the steel chain.

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Re: Sur-Ron - New Mid drive Bike

Post by brumbrum » Oct 20 2018 1:23am

Allex wrote:
Oct 19 2018 4:33pm
n2mb wrote:
Oct 19 2018 4:20pm
Antenor wrote:
Oct 19 2018 3:43pm
Since i have electric bikes i dont apreciate the way i did the gas motor sound...e fell more relaxed and connected to nature without noise...its shame that in portugal nobody is selling surron.
That's funny. Coming from a direct drive E-bike with a sine wave controller, the Sur Ron seems loud to me! I don't have a the X controller, so maybe it gets quieter with that upgrade.
Not really! But with the belt it will. NOW... who want some belts on this thing?!
I do, and i don't even own a Sur-ron.
My NYX and cromotor build
viewtopic.php?f=6&t=74615
My LMX 161 dirt bike build
viewtopic.php?f=6&t=94074

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Re: Sur-Ron - New Mid drive Bike

Post by madin88 » Oct 20 2018 4:28am

motomoto wrote:
Oct 19 2018 10:39pm
I might do something weird with the rear pulley to make it easy to machine like skip every other tooth. The rear sprocket will still have
way more teeth engaged than the front. The pulley stock I have for the front pulley is 32 tooth 8mm GT2 for Gates Poly Chain GT Carbon. The belt will be 12mm width. It should be really quiet compared to the steel chain.
Such pulley with skip tooth would look strange, but it's no bad idea if you want to make CNC fabrication faster.
I have designed my own 108T pulley for 8M 12mm wide belt, but i had to realize the original tooth profile from gates needs to be adjusted so that it can be milled (with a 2mm mill in my case). Imagine a mill with 2mm diameter and >12mm work length!

Normally those pulleys are "gear hobbed", but this means the guide flange(s) are always separate parts..

Motomoto, did you check if there is a standard belt length available which would fit the axle-to axle distance of the surron?
I would look for that first, and then settle on the size (tooth count) of the pulleys.

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Oct 20 2018 10:52am

I will have to play with the belts available and the number of teeth to find something that will work. There might only be one choice
so having different ratios is a compromise with a belt system. The 32 tooth I mentioned for the front sprocket isn't right. I have 20
tooth pulley stock which is a similar to the stock front sprocket in diameter and I will probably use that. The number of teeth engaged
for the power being transmitted is way under the recommended number but hopefully that just means a shorter belt life and not the
belt teeth being ripped off.

The belt drive will also involve taking the swingarm off to get the belt on. PITA if it needs changing often. The belts are expensive
also. Lots of compromises but it will be quiet and not messy with chain lube. It should be for road riding or dry conditions and not
for mud.

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Re: Sur-Ron - New Mid drive Bike

Post by DanGT86 » Oct 20 2018 11:08am

I think you get some wiggle room by increasing the belt wrap with an idler. Still sucks to design and be under spec from the start though. Can you get a batch of extra wide belts made to help with power handling? Ive heard the belts skip teeth if you get too far out of the spec on power handling per tooth.

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Re: Sur-Ron - New Mid drive Bike

Post by madin88 » Oct 20 2018 11:33am

motomoto wrote:
Oct 20 2018 10:52am
I have 20 tooth pulley stock which is a similar to the stock front sprocket in diameter and I will probably use that. The number of teeth engaged
for the power being transmitted is way under the recommended number but hopefully that just means a shorter belt life and not the
belt teeth being ripped off.
From what i know the maximum torque rating for a 20T drive pulley is around 40Nm (for mentioned belt), so the lifetime definitely would not be good.
If you cannot use more than 22T i would say forget it.

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Oct 21 2018 12:12am

madin88 wrote:
Oct 20 2018 11:33am
motomoto wrote:
Oct 20 2018 10:52am
I have 20 tooth pulley stock which is a similar to the stock front sprocket in diameter and I will probably use that. The number of teeth engaged
for the power being transmitted is way under the recommended number but hopefully that just means a shorter belt life and not the
belt teeth being ripped off.
From what i know the maximum torque rating for a 20T drive pulley is around 40Nm (for mentioned belt), so the lifetime definitely would not be good.
If you cannot use more than 22T i would say forget it.
Or what about a larger pulley system, perhaps L?

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Re: Sur-Ron - New Mid drive Bike

Post by madin88 » Oct 21 2018 2:47am

3DTOPO wrote:
Oct 21 2018 12:12am
Or what about a larger pulley system, perhaps L?
What you could do is using a belt with more width than 12mm if it fits (next size is 21mm i think), but it still would require a 22T on the front for reasonable lifetime (at least Gates recommends it).
You would not be happy if the belt is prone to failure after short time. Imagine you are somewhere in the woods and you need to chove the bike home..
Having a more silent drive train with smooth regen braking btw would be only worth the effort and costs if lifetime is similar to the chain IMO.

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Re: Sur-Ron - New Mid drive Bike

Post by Allex » Oct 21 2018 5:18am

Motomoto, can we fit 22t on the bike?

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Re: Sur-Ron - New Mid drive Bike

Post by madin88 » Oct 21 2018 6:45am

I fit helps a 22t pulley would require about 62-65mm diameter (overall with the belt on).

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Re: Sur-Ron - New Mid drive Bike

Post by jph3 » Oct 21 2018 8:31am

Endurocross in Denver last night... and they announced that Alta shut down? Anyone else heard that news?

EDIT. link to confirmation. That sucks
https://www.cycleworld.com/alta-motors- ... operations

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Re: Sur-Ron - New Mid drive Bike

Post by Offroader » Oct 21 2018 8:51am

This is why I posted before that Sur-Ron can easily go out of business. These electric bikes are really a niche and the market for them is quite small. Yes you can make them in your basement forever, but no way you can support a large factory producing them on an assembly line.

This is why I wouldn't wait too long to pick one up because if Sur-Ron goes out of business I doubt we will see a similar product in our lifetime.

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Re: Sur-Ron - New Mid drive Bike

Post by macribs » Oct 21 2018 9:16am

You got a point offroader, but you also got to factor in that Alta and Sur Ron are not really comparable in any way. Alta uses high grade parts from known vendors all around and the manufacturer their bikes in the US with the much higher labor costs. Sur ron uses more mid tier parts and are put together in China where labor is cheap and where they can pick up parts or outsource parts for pennies on the dollar compared to doing this in the west. And with all that in mind I think what Alta has done so far is awesome. They designed and dreamed up this bike from scratch. They put it to races, the keep improving and innovating and I really hope investors are recognizing the amount of work, the risks and the effort and skills that are put into the Alta brand so that this company can continue their journey and keep pushing electric dirt bikes, dual sports and motards to new customers.

Also the share parts and labor costs of Alta makes that production much more financial intensive. Alta got to put much more money into parts and labor before the return from the sale of each unit comes in. So they need more initial money up front to get started, but also because of the costs they are the ones that will need the cash flow most. And with a smaller market and a price tag above ice bikes they got a tougher sale.

If your overall costs are lower and you also got a huge domestic market like sur ron does the risks goes down, then needed capital base is much lower and amount of money tied up in each bike from parts to finished product that a customer bought and paid for is much smaller. That being said, even with a the domestic market and making a name for them self in the west as well, the e-bike market is still small. And even at the price point we know sur ron is a great deal, the final price shipping the bike to your door might be too much to most of the hobby riders still. For now I think true enthusiasts are the buyers, hopefully this group will grow as many more get to experience and see these amazing bikes.

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Re: Sur-Ron - New Mid drive Bike

Post by Rix » Oct 21 2018 10:10am

jph3 wrote:
Oct 21 2018 8:31am
Endurocross in Denver last night... and they announced that Alta shut down? Anyone else heard that news?

EDIT. link to confirmation. That sucks
https://www.cycleworld.com/alta-motors- ... operations
Don't think the fat lady has sung yet. Next week or 2 will be interesting.

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Re: Sur-Ron - New Mid drive Bike

Post by Jonathan1981 » Oct 21 2018 3:08pm

Rix wrote:
Oct 21 2018 10:10am
jph3 wrote:
Oct 21 2018 8:31am
Endurocross in Denver last night... and they announced that Alta shut down? Anyone else heard that news?

EDIT. link to confirmation. That sucks
https://www.cycleworld.com/alta-motors- ... operations
Don't think the fat lady has sung yet. Next week or 2 will be interesting.

Yeah man, I totally agree, I mean, they set a precedent in electric off road moto. I can't see this going unrecognized... frock HD anyway. Bunch of old dinosaur money. They need to partner with the asian's. It's that simple *winks.

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Re: Sur-Ron - New Mid drive Bike

Post by 3DTOPO » Oct 21 2018 4:20pm

madin88 wrote:
Oct 21 2018 2:47am
3DTOPO wrote:
Oct 21 2018 12:12am
Or what about a larger pulley system, perhaps L?
You would not be happy if the belt is prone to failure after short time. Imagine you are somewhere in the woods and you need to chove the bike home..
Having a more silent drive train with smooth regen braking btw would be only worth the effort and costs if lifetime is similar to the chain IMO.
I understand; that is why I was suggesting a beefier pulley. My understanding is that L size belts are stronger for the same width as GT2 belts.

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Re: Sur-Ron - New Mid drive Bike

Post by motomoto » Oct 21 2018 10:22pm

I've been following the Redshift/Alta bike thing since the beginning. The problem is that they took 8 years and 30 million
dollars to get off the ground and start selling bikes. That is quite a burden to pay back the investors and make a profit.

They had the design by committee thing going which always take 10 to 20 times as long as one person with a vision and
the skills to pull it off.

Let's see what happens. If someone is willing to gamble a shit ton of money and buy it, then maybe it is worth saving,
but I wouldn't. Like the guy who lived under a brothel, too much f#%king overhead.

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Re: Sur-Ron - New Mid drive Bike

Post by pipeking » Oct 22 2018 6:12am

3DTOPO wrote:
Oct 21 2018 4:20pm
madin88 wrote:
Oct 21 2018 2:47am
3DTOPO wrote:
Oct 21 2018 12:12am
Or what about a larger pulley system, perhaps L?
You would not be happy if the belt is prone to failure after short time. Imagine you are somewhere in the woods and you need to chove the bike home..
Having a more silent drive train with smooth regen braking btw would be only worth the effort and costs if lifetime is similar to the chain IMO.
I understand; that is why I was suggesting a beefier pulley. My understanding is that L size belts are stronger for the same width as GT2 belts.
A belt drive would be great for the su-mo version, but unless I'm missing something, dirt bikes don't use belt drive for a reason.

For that same reason, you can get a chain kit for the primary...

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