Rockstar owners

[PedalUma]

Two observations so far: You will need a Park Tool DT-2 or similar; watch the sharp edges on the seat stay where the brake hose goes into the frame. It will be moving there with the suspension. It is like a serrated steak knife against the hose.

 

[fauconnier]

PedalUma when your built is finished can you share some dimensions with us. I am interested in low and high saddle heights from the ground and from the lowest part of the pedals (inseam), also can you confirmed the other Sondors numbers. Thank you.

 

[troehrkasse]

I spoke with a Sondors rep yesterday and she said that the entire line of Sondors Elite ebikes have the same motor which is only 95nm. The review for the Sondors LX on this website says it's 160nm. She told me that was wrong and 95nm is what she has on her spec sheet. I looked through this thread and did not find anyone talking about this. Is this a known thing?

Turns out 95nm is correct, I'm updating the LX review to reflect this. The Ultra motor is capable of 160nm of torque, but it's not putting out that much due to how it's configured on the LX (and presumably the rest of their Elite line).

 

[PedalUma]

Turns out 95nm is correct, I'm updating the LX review to reflect this. The Ultra motor is capable of 160nm of torque, but it's not putting out that much due to how it's configured on the LX (and presumably the rest of their Elite line).

Two more build details: The gap between the wheel magnet and the speed sensor was too large at about 12mm. I stacked on a second magnet to reduce the gap and increase the magnetic force, using adhesive shrink tube to secure it. The good looking display requires a shim but does not come with one.

 

[teskow]

I spoke with a Sondors rep yesterday and she said that the entire line of Sondors Elite ebikes have the same motor which is only 95nm. The review for the Sondors LX on this website says it's 160nm. She told me that was wrong and 95nm is what she has on her spec sheet. I looked through this thread and did not find anyone talking about this. Is this a known thing?

This just doesn't make any sense to me to de-tune a beautiful, powerful motor from 160NM down to 95NM unless Sondors figures the bikes themselves and the current drive train components aren't strong enough to handle that power. EBR sort of eludes to this. With so many great features to this motor could they be planning to go to a belt drive with a shifting hub that could handle the full potential of the Bafang M620 in the future? I certainly would go for that in a big way..
Auto makers are famous for detuning engines on new production as a test of the components and then boasting up to full potential later when the bugs are worked out.

 

[fauconnier]

95 NM instead of 160 NM and " grey bike broke chain while climbing " in video chasing Sondors Rockstar at 1:17 25 lbs of dead weight.

 

[Lightning 123]

The guy said that it was caused by being in the wrong gear while climbing up a fairly steep grade. Think about this, they
Wouldn't want to have multiple failures of
The the drive system coming apart right at the start of launching a new product.
If the torque levels were set too high that
surely would be the result.
It would be considered a failure and would cast serious doubt on whether the product was worth the investment or just an overpriced piece of junk. So I think that we should take what they give us to
start with and then go from there. We will get this figured out soon enough.

 

[fauconnier]

I knew they used a 25A controller instead of M620 30A , it's only a 16% power decrease I can live with, now it's 40 % less power with a 23% weight increase. I was naive, I thought they have solve the chain and cassette stress problem. Quite far from the E bike I bought.

 

[troehrkasse]

This just doesn't make any sense to me to de-tune a beautiful, powerful motor from 160NM down to 95NM unless Sondors figures the bikes themselves and the current drive train components aren't strong enough to handle that power. EBR sort of eludes to this.

160 down to 95 sounds like a huge loss... but honestly 95NM of torque is a lot, way more than most people will ever need. I've always heard that 80 and above are plenty for a mid-drive eMTB that can leverage the drivetrain. Test riding the LX I climbed a pretty steep hill in 5th gear and accelerated up it without issue, in low gear it will climb pretty much anything. For comparison, on my 1200cc motorcycle the torque peaks at 126nm.

I think some of the reduction may be for saving the drivetrain, and some of it may be having the motor only draw 750 watts nominal (likely to comply with California regulations, among other places). Higher power draw would also mean less range. I'm not an expert on the relationship between wattage and torque and the finer points of the electronics... so take that with a grain of salt

 

[PedalUma]

160 down to 95 sounds like a huge loss... but honestly 95NM of torque is a lot, way more than most people will ever need. I've always heard that 80 and above are plenty for a mid-drive eMTB that can leverage the drivetrain. Test riding the LX I climbed a pretty steep hill in 5th gear and accelerated up it without issue, in low gear it will climb pretty much anything. For comparison, on my 1200cc motorcycle the torque peaks at 126nm.

I think some of the reduction may be for saving the drivetrain, and some of it may be having the motor only draw 750 watts nominal (likely to comply with California regulations, among other places). Higher power draw would also mean less range. I'm not an expert on the relationship between wattage and torque and the finer points of the electronics... so take that with a grain of salt

I am not a reliable source. Do not trust me. Here is what I found.
Low Saddle, Pedal to Saddle Height 78c
Low Saddle, Ground to Saddle 95c.
Max, Pedal to Saddle 95c
Max, Ground to Saddle 114c.
The battery charges to 90% when it is in the off position and automatically stops chagrining. Flip the battery ON for the last 10%.
The weight is 19.3Kg front and 19.65 to the rear. That is about 88-pounds. Sorry, it is hard to photograph an LED with a flash.
No fenders were included.
This bike is very loud, it whines. The motor continues to power forward for about 2.5 seconds after the rider stops pedaling.
Finally and anecdotally, I rode a bike path which crosses train tracks. Posts and fences are setup so that a rider must slow and weave so as to not plow at full speed into a train. This bike did not handle well with the weaves. It felt clunky.
Why should it be just 88-pounds when I put 225-pounds into the frame's suspension?
The basket was to enhance the delivery process. The guy's wife loved it!

 

[Ebiker33]

That motor is very capable of doing much higher numbers.
Watt Wagons has a version that runs 3000W, but you can only ride it for 1 hour.
When they say it's powered down to 95nm it's because they downgraded the controller to 25 amps.
But then you do the math even with that slagging of the power 25A X 48V = 1200W peak output. Rated at nominal 750W to stay within current laws.
Are you telling me 1200 Watts can only produce 95nm on that motor ?
They are the very first company to downgrade the ultra motor in such a large way, stock controller is 30amps so 1440W peak, can you seriously believe a difference of 240 Watts is pulling that nm that far down?

The upside is you will never burn this motor out on this Ebike as it's made to do so much more. That fact that he broke a chain shows the power of this motor, but if you have read enough forum posts on the Ultra that is the number one complaint on that motor, it eats chains if you really push it and don't figure out the gearing. He mentions throttling, it even being part of the cause of the break of the chain going up hill. Watt Wagons puts a 750W limiter on their throttle to prevent their way more powerful motor controller from killing it's components. But a Gates belt is one answer, but even then the CVT can't handle all that power it kills them on the instant power via the throttle. But it can handle the gradual build up of pedaling.

Here's what I think, Sondors went to Bafang and said what does 750W of power produce on the ultra for nm, the answer is 95nm. They probably also have limiter on the throttle at 750W just like the Watt Wagon again 95nm from a certain point of view. However if you go into the display and crank everything to the max and pedal like mad in the highest possible setting without the throttle, you are pulling up more than 95nm.
Of interest the limit on some CVT is right around that 95nm, or your warranty is voided.

 

[Ebiker33]

Same person posted another photo:


View attachment 82144

Love the color almost blue grey in the natural sunlight, I like it much better than the yellowish one.

 

[Merle Nelson]

That just to bad , I've been reading the reviews for a nine month since placed my order, sondors send me an email in December that my rockstar is ready and will be shipped soon , but then they kept changing delivery date every month blaming covid , I was patient till I got another email yesterday that my rockstar won't be delivered till end of May and I don't know if that even truth ,
So i canceled my order sadly , it's just to long , I will start looking for something in stock Giant or Specialized or maybe Hibike , even if I have to pay more I don't care anymore.

Tough go! Sorry it didn't work out for you like all good business transactions should. (Full stop.)

 

[Merle Nelson]

Anyone who has an early order date for a Rockstar and it's not working out for you please let us (me) know.

Instead of canceling consider being a capitalist. (Seriously.)

 

[Lightning 123]

I am not a reliable source. Do not trust me. Here is what I found.
Low Saddle, Pedal to Saddle Height 78c
Low Saddle, Ground to Saddle 95c.
Max, Pedal to Saddle 95c
Max, Ground to Saddle 114c.
The battery charges to 90% when it is in the off position and automatically stops chagrining. Flip the battery ON for the last 10%.
The weight is 19.3Kg front and 19.65 to the rear. That is about 88-pounds. Sorry, it is hard to photograph an LED with a flash.
No fenders were included.
This bike is very loud, it whines. The motor continues to power forward for about 2.5 seconds after the rider stops pedaling.
Finally and anecdotally, I rode a bike path which crosses train tracks. Posts and fences are setup so that a rider must slow and weave so as to not plow at full speed into a train. This bike did not handle well with the weaves. It felt clunky.
Why should it be just 88-pounds when I put 225-pounds into the frame's suspension?
The basket was to enhance the delivery process. The guy's wife loved it!

Thanks for the honest first impressions of the first ride and the heads up on the potential problems look out for on the assembly.

 

[ElevenAD]

That isn't what I understood, it was supposed to be 160 nm

when they first started the campain Sonders stated that all 3 bikes would have a tuned down version of the M620Ultra with 750watts and 95nm vs the unrestricted Ultra's 1000watts and 160nm, this was the reason i did not purchase a Rockstar,why even use an ultra if its not full on, they could have just used a cheaper and lighter M600, very strange

 

[ElevenAD]

Maybe the motor has been programmed to limit the torque.

Bafang Ultra (G510) Specs:

View attachment 82540

it has,not sure why

 

[Lightning 123]

when they first started the campain Sonders stated that all 3 bikes would have a tuned down version of the M620Ultra with 750watts and 95nm vs the unrestricted Ultra's 1000watts and 160nm, this was the reason i did not purchase a Rockstar,why even use an ultra if its not full on, they could have just used a cheaper and lighter M600, very strange

I think I read through and disregarded that part of it and fixated on the capabilites of the m 620 motor.

 

[fauconnier]

Nm is a measure of torque not power. In most case it's obtained with a gear box where rotational speed is sacrificed to increase torque. It's exactly like a normal 12 speeds bicycle. For this reason, a 1200 cc. road motorcycle can have only 126 Nm of torque and a slow Trial electric motorcycle, equivalent of a 125cc, can deliver 600 Nm of torque. In this case, because I suppose Sondors didn't change the motor gear box but only the programming and electronics, they lowered the Amp. to approx. 16 A. to meet the 750W requirement and/or to respect the limits of the other components. The torque decrease is the direct result of the lower Amp. in the same proportion. At the end we get a 12 lbs motor that deliver the same power of a lot smaller motor with less watts and more gearing. The battery and frame being proportional in weight and theoretical power to the M620, it explain the very high autonomy and exceptional weight of the Elite bikes. This is what improvisation leads to.

What surprise me the most is that the chain broke climbing a hill on a dirt trail with limited adherence. I suspect the chain line, a clunky speed change or the result of the bike not having throttle cut on the speed selector, is it the case ?

 

[teskow]

"What surprise me the most is that the chain broke climbing a hill on a dirt trail with limited adherence. I suspect the chain line, a clunky speed change or the result of the bike not having throttle cut on the speed selector, is it the case ?"

More than likely it was a weak or faulty chain in this case.