Sur-Ron - New Mid drive Bike

FlightService said:
Nah. My degree from a top 30 Engineering School in Mechanical Engineering, 10 years of Engineering experience and http://ffden-2.phys.uaf.edu/211_fall2010.web.dir/Michael_Stanfill/FourBar.html all disagree with you.

It's still a 4 bar linkage

On a 4-bar the swingarm is splint into chain stay, seat stay and rocker as you can see.
By doing so the virtual pivot point can be moved far forward to prevent squat during braking or pedal bob.
I am no expert, but doesn't the Surron have a fixed pivot point?
 
(all caps added for emphasis on possible confusion points)

madin88 said:
On a 4-bar the swingarm is split into chain stay, seat stay and rocker as you can see.

The rear SUSPENSION of the diagram above is the swingarm, upper A-arm, rocker arm, frame (not shown, but is the base of the system) and shock. The wishbone is just the bracket that attaches the rocker arm to the swing arm and is considered part of the swing arm. So the rear SUSPENSION SYSTEM 4 bar linkage is the swingarm, upper A-Arm, Rocker arm and the frame. The shock dampens the motion and suspends the weight yet doesn't dictate directional motion (if they did the math right, if they did it wrong they shock won't last long which is why I think in another pick the shock to rocker arm had another link).

madin88 said:
By doing so the virtual pivot point can be moved far forward to prevent squat during braking or pedal bob.
I am no expert, but doesn't the Surron have a fixed pivot point?

The attachment of the SWING ARM to the frame is a fixed point arrangement. The swing arm IS NOT the entire suspension system. Just one part. There are 4 bar linkage SWING ARM setups out there, the SunRon isn't one.

But this is a 4 bar linkage SUSPENSION setup. The swing arm, on it own, is a single point arrangement, as is the upper A-Arm, on its own.

So you are correct in the SWING ARM being of a single point type, but the REAR SUSPENSION SYSTEM is a 4-bar linkage. It's the difference in saying that the rim is the wheel vs saying the hub, spokes and rim is the wheel. You are referencing a particular part of the entire system, instead of the system as a whole.

I hope this helps clarify.

Now if you really want to bake your noodle, look up Honda's Unit ProLink rear suspension used on their MotoGP bikes. The entire rear unit is held on with two bolts. The shock compresses against the suspension set up and NOT the frame.

12Oct_Tech_ProLink_03_gallery_large.jpg
 
cool. what were you racing the last half,an 80cc? How long is your battery lasting at that pace?
 
fantastic vid^^
It brings a lot of appetence for riding on such tracks :)
 
That's quite impressive performance on a motocross track, considering it isn't really being marketed as a motocross bike. Obviously the suspension is doing its job ok, and there is quite a bit of power. I'm keen to see how it will go on singletrack and semi-trials riding.. hope you get a chance to ride it in varying terrain, and get video / post reports.
 
cool. what were you racing the last half,an 80cc? How long is your battery lasting at that pace?

It was an 80 or an 85. I think 7 laps was 25% battery use at full pace.

Trail riding and single track would work great with this bike. I would watch it on the long steep climbs as it would
overheat. It's happened to me twice where something cuts the power in half suddenly. It's either the battery, BMS or the
controller. The motor is always barely warm when the power cuts out.

I am super impressed with the performance. It handles great but isn't as cushy as a motocross bike with only 8" of suspension
vs 12" on a full sided bike.
 
Great video!
Seems to me that the simplest solution to combat the overheating is to gear the bike down a little. A 1 tooth smaller front sprocket might be enough?
 
Great video!
Seems to me that the simplest solution to combat the overheating is to gear the bike down a little. A 1 tooth smaller front sprocket might be enough?

I was thinking the same thing. For that track a 10% change would make the bike faster out of all the turns and not hurt the top end speed.

A guy sent me some video of me that day.[youtube]AIlTgxDUa5I[/youtube]
 
motomoto said:
Trail riding and single track would work great with this bike. I would watch it on the long steep climbs as it would
overheat. It's happened to me twice where something cuts the power in half suddenly. It's either the battery, BMS or the
controller. The motor is always barely warm when the power cuts out.

That sounds like the controller. That should be easy to fix or at least improve on.
 
fechter said:
motomoto said:
Trail riding and single track would work great with this bike. I would watch it on the long steep climbs as it would
overheat. It's happened to me twice where something cuts the power in half suddenly. It's either the battery, BMS or the
controller. The motor is always barely warm when the power cuts out.

That sounds like the controller. That should be easy to fix or at least improve on.

I suspect that like the other golden motors the heat path is very poor, so unless your talking about the actual winding temps it could be that the inside is cooking while the outside is still only warm - ie might be a issue with the motor rather than the controller.
 
You are right, it does have lousy heat conduction from the coils to the outside.3000 golden inside.jpg
 
Does anyone have any suggestions for a better motor to replace the 180 mm diameter Golden motor?
 
Wouldn't fit. Need something more power concentrated with 180 mm diameter maximum size
 
Ask Skeetab how the Denzel 7.5 kw motor is working for him. I don't know if he ever said if it was worth it or not. They are smaller than 180mm for sure.
http://www.eastgem.net/d7500.html
07-acc-d7500-06-size.jpg

07-acc-d7500-07-size.jpg

Plus they are only $320 shipped.
Are you really tearing the bike down already? Your video seems like the bike works very well for what it is. I guess the problem with most of us here, you always think things could be better. My wife tells me I have a problem with that, too.
I pushed out my purchase of the bike till Spring as its too cold to ride for me here. They weren't quick enough to get it to me in the Fall.
 
Could you use the Ferro-Juice (Transmission Fluid) that the hub guys are using?
Or is the frame of this motor wide open.
 
Re: Motor cooling.
I remember a Russian guy saying that fitting forced air cooling to a Cyclone motor made a huge difference to how hard / long he could ride before temperature rise became a problem.
From your photo it looks as though there is a bit of room for air to circulate around the windings, so it might be worth a try cutting 2 holes in the case of the motor, fitting a small 12V centrifugal fan and duct its output to one of the holes.
I haven't seen the motor, so I don't know how well sealed or how open it is already. If it is well sealed, then cutting holes would have some disadvantages, allowing ingress of water, dust, mud etc. But I thought it worth making the suggestion for you to consider.
 
Post some detailed pics of the motor and I will post pics of our bike motors, as I’ve been told that they are the NEW motor...

The bikes will get a workout this weekend so I will be able to update soon.
 
Oil filling a low rpm direct drive hub motor has worked well for conducting heat from the windings to the casing. At the low speeds involved, the viscous drag is apparently not too much of an issue.
However this motor is spinning MUCH faster, and oil or other fluid inside the motor would probably cause significant drag, which would be counter-productive: the extra drag would require extra current in the windings to overcome the drag, creating yet more heat.

The windings might not get hotter, but the wasted energy would not be a good thing.
 
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