Custom frame for the Cyclone Coaxial motor

[Chambers]

Bit of work on an alternative swing-arm design as discussed on pg. 5

cyclone coaxial -29.jpg (109.42 KiB) Viewed 1353 times

[Chambers]

Refining the details a bit.

cyclone coaxial -30.jpg (77.2 KiB) Viewed 1304 times

[GP-tech]

Have a look here

viewtopic.php?f=31&t=106778

the stepdown bend prevents from thermal expansion in all directions. as far as my knowledge goes, was/is that a big reason cells are failing in a pack.

[Chambers]

Have a look here

viewtopic.php?f=31&t=106778

the stepdown bend prevents from thermal expansion in all directions. as far as my knowledge goes, was/is that a big reason cells are failing in a pack.

OK cool, That's kind of what I was picturing and your theory does make sense - Kind of a thermal strain relief.

[GP-tech]

Sorry missed the new posts...that looks really sweet!

is the pivotpiont in the chainline? If its higher or lower will lift up or pull down the rearwheel...something to consider at 3kw, maybe

sharp edge from the horizontal bar to the short round bar(swingarmpivot) will be a weak piont too.

but still...looking to get a bad ass bike!

which CAD are you using?

[Chambers]

Thanks, I use autodesk inventor.
Consider the model more of a loose concept than an exact depiction, there are a few areas that will end up slightly different during fabrication. The swingarm and linkage is the area that still has the most work before im 100% happy with it - must have changed my mind on it 10 times already

[Chambers]

So since it looks like my Nucular 12f I ordered in March won't be available until 'after NY' (so 9 months total or more)viewtopic.php?f=31&t=75494&start=1425
I have ordered a Yuyang King YKZ7250 with bluetooth.
https://www.aliexpress.com/item/3303913 ... 3fd2p5Ps2k

I will be doing a few mods to this controller - If I break it at least it was cheap

I guess I will have to see how I feel if/when the nuc' is finally ready........

[GP-tech]

Haha, i know this loose concept things pretty damn good! (piles of them in my workshop)

Unfortunately iam sticking with Fusion360 atm. otherwise it would be easy to mod some things. maybe the fastest way is a good sideview from your designs and with the good old fashion way in"paint" i will explain a bit more what i meant

Its really worth waiting for the controller, no one here in germany will sell one after they had one. Still the same waiting time for us...used to be that the russians had all weapons on storage for, the old days

Whats your goal for the linkage system?
For me iam in love with monoswingarm and shock direct mounted...but that will move the short right in the toptube.

[Chambers]

Haha, i know this loose concept things pretty damn good! (piles of them in my workshop)

Unfortunately iam sticking with Fusion360 atm. otherwise it would be easy to mod some things. maybe the fastest way is a good sideview from your designs and with the good old fashion way in"paint" i will explain a bit more what i meant

Its really worth waiting for the controller, no one here in germany will sell one after they had one. Still the same waiting time for us...used to be that the russians had all weapons on storage for, the old days

Whats your goal for the linkage system?
For me iam in love with monoswingarm and shock direct mounted...but that will move the short right in the toptube.

Yeah I don't hear anyone complaining about the nucular once they have one, But I can't put this project on hold for another 5-6 months just to wait.

Really the goal of the linkage is to have a better ride feel throughout the travel, I basically copied a Turner DHR rear end then modded from there. I have thought about four bar (specialized) style linkage as well but I don't want to run into patent issues if I ever get to the point of selling something, I've also looked at the Norco A-line style recently.

I will probably end up making a few different iterations of the frame but I want to get it as close to right as possible with the first one.

Below is a side view of the current set up, now that I look at it I can already see a few issues

cyclone coaxial -31.jpg (104.04 KiB) Viewed 1186 times

[GP-tech]

So you are flexing the hole rearend(swingarm). With all these edges inside, cracking will start there. My experience out of 22year riding the sh.... out of two wheelers---dont get to fancy with suspension itself. As long as rearwheel travel goes kinda linear with shocktravel it will ride perfect. I even changed out all needle bearing on linkages for pfte bushings...because bearings are non good idea for short movements. And used to ride 500cc dirtbikes really hard.

[Chambers]

Quick animation showing the swing-arm movement. Too tired to make the spring active so the bracket is sliding instead

[Chambers]

Long time no posts.....

I've been working in the background building some new welding benches a pan-brake and working on a slip roller this week in order to fabricate the frame.

I have the sheet metal and a few other bits and bobs but still waiting on most parts.

I have also changed the frame again slightly (below is a quick peek) I'll wait to post anymore pics until fabrication is fully underway.

cyclone coaxial -33.jpg (34.78 KiB) Viewed 1024 times

[Tommm]

Long time no posts.....

I've been working in the background building some new welding benches a pan-brake and working on a slip roller this week in order to fabricate the frame.

I have the sheet metal and a few other bits and bobs but still waiting on most parts.

I have also changed the frame again slightly (below is a quick peek) I'll wait to post anymore pics until fabrication is fully underway.
cyclone coaxial -33.jpg

Motor looks a bit low on that pic

[Chambers]

Same height as always, I think it looks that way because the swingarm is different

[qwerkus]

So you are flexing the hole rearend(swingarm). With all these edges inside, cracking will start there. My experience out of 22year riding the sh.... out of two wheelers---dont get to fancy with suspension itself. As long as rearwheel travel goes kinda linear with shocktravel it will ride perfect. I even changed out all needle bearing on linkages for pfte bushings...because bearings are non good idea for short movements. And used to ride 500cc dirtbikes really hard.

I second this advice, especially the part about bearings vs bushings. Never really understood the point of using bearings on bike suspension pivots anyway, besides hype.

[Chambers]

So you are flexing the hole rearend(swingarm). With all these edges inside, cracking will start there. My experience out of 22year riding the sh.... out of two wheelers---dont get to fancy with suspension itself. As long as rearwheel travel goes kinda linear with shocktravel it will ride perfect. I even changed out all needle bearing on linkages for pfte bushings...because bearings are non good idea for short movements. And used to ride 500cc dirtbikes really hard.

I second this advice, especially the part about bearings vs bushings. Never really understood the point of using bearings on bike suspension pivots anyway, besides hype.

Funny you both say that, Turner use bushings also. I read an artical about it a few weeks ago. Cheers

[Joe King1]

Purely in the interest of discussion purposes I'll take the opposing view that bearings ARE a better choice in THIS application.
Chambers is not building a 500cc 250 lb. dirtbike to be ridden at speeds in excess of 60 mph....he's building a 60-70lb. ebike that will rarely exceed 30 mph...BIG DIFFERENCE.

I just took apart my rear suspension on my 60 lb - 30 mph ebike with full intention of having to replace all the ball bearings in the swingarm & linkage after 2 years (1600 off-road miles) & determined it wasn't necessary.

Bushings lack the structural integrity to resist torsional loads that steel bearings have. Ball bearings have the obvious advantage of less friction & will maintain their size throughout their useful life.

[Chambers]

Purely in the interest of discussion purposes I'll take the opposing view that bearings ARE a better choice in THIS application.
Chambers is not building a 500cc 250 lb. dirtbike to be ridden at speeds in excess of 60 mph....he's building a 60-70lb. ebike that will rarely exceed 30 mph...BIG DIFFERENCE.

I just took apart my rear suspension on my 60 lb - 30 mph ebike with full intention of having to replace all the ball bearings in the swingarm & linkage after 2 years (1600 off-road miles) & determined it wasn't necessary.

Bushings lack the structural integrity to resist torsional loads that steel bearings have. Ball bearings have the obvious advantage of less friction & will maintain their size throughout their useful life.

Based on what I've read recently bushings would be 'better' BUT for bushings to work effectively the fabrication tolerances need to be very close. Bearings work well but are easier to damage in an off road environment due to water and dust ingress and inconsistent wear can be an issue when they are not moving in full rotations like in a swingarm.

[GP-tech]

Purely in the interest of discussion purposes I'll take the opposing view that bearings ARE a better choice in THIS application.
Chambers is not building a 500cc 250 lb. dirtbike to be ridden at speeds in excess of 60 mph....he's building a 60-70lb. ebike that will rarely exceed 30 mph...BIG DIFFERENCE.

I just took apart my rear suspension on my 60 lb - 30 mph ebike with full intention of having to replace all the ball bearings in the swingarm & linkage after 2 years (1600 off-road miles) & determined it wasn't necessary.

Bushings lack the structural integrity to resist torsional loads that steel bearings have. Ball bearings have the obvious advantage of less friction & will maintain their size throughout their useful life.

I will step in for discussion purposes. Thanks Joe and good pionts, you are right about the bearings are a good solution in this application (if proper machined after welding and really good looked after). But lifespan is short and must be changed frequently, on failure they really often jam up and destroy their seats or break their frame-part. Their light friction+non slipstick effect is the main advantage and this gets more interesting as speeds get higher!

But my practical experience repairing and machining lead in PTFE or PA6(printable) bushings on (stainless) steel, as rust seams to be the only problem.... Easyer to make, better dirt resistance, shock absorbing and damping, sightly adjustable by clamping force, non noticeable change on rearends feeling(aka slipstick) even at full speed. Downsides: cooling at machining, hard to calculate the pressfit diameter change for the inside beforhand.

Considering the forces (same torque on this bike as an 500cc at the swingarm pivot) and movement at swingarm pivot... An engineer would(should)go for bushings! ( over 100 pieces the engineer gets told to go bearings, out of cost reasons)

Even rubber bushings all cars still using today are really good for this application. And car ball joints are PTFE-steel bushings as well. My Vertemati 495 has PTFE-coated-steel bushings compaired with Öhlins suspension factory side. These coated bushings are the same than in "every telescopic fork" on the marked

The damage(short lifespan) on bearing comes from to short movement (unevenly wear) of the balls inside which leads to the displacement of lubricant, as well as rust. many small balls and big ball track diameter is necessary, which makes them more expensive then bushings...

[GP-tech]

@Chambers

Frame is looking really good and sturdy...excellent work

Motor is mounted just through the bolt pattern?

[Chambers]

@Chambers

Frame is looking really good and sturdy...excellent work

Motor is mounted just through the bolt pattern?

Bolts on left side - clamping strap on right side with a gap in the middle to put some heat-sinks if needed.
Thanks for your input too!

[Chambers]

So I finally eeked out some time this afternoon - Got sick of waiting for my CNC machine parts to arrive and decided to just do it by hand.... I figure I can always re-make it if I'm not happy with the result. So I marked the frame out on sheet metal (1.2mm)
and cut it with a cut off wheel on my grinder

20201108_140607.jpg (332.37 KiB) Viewed 399 times

Then folded it in my DIY Pan-brake - You can see by the shape of the folded edge that I need to add some strength to the middle of the brake ( Wider radius in the middle)

20201108_165903.jpg (343.98 KiB) Viewed 399 times

Then I made some paper templates and cut out the motor mount plates ( these are 3mm plate)

20201110_175927.jpg (275.9 KiB) Viewed 399 times

Motor mount plates complete - One side clamping one side bolting

20201112_191248.jpg (455.62 KiB) Viewed 399 times

Rough mock up of how its going - Ignore the head-tube angle I cut it oversize (angle) so I can trim it back. The two side plates will be joined together at the top with another piece of plate with a cut out in it to access the wiring, There will also be a small bolt on plate to cover the wiring hole.

[Chambers]

Controller arrived - This thing is BIG ....Well compared to the nuc' dimensions

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I plan on removing the guts from the shell modifying it then potting it - Should be able to remove a fair bit of bulk.

20201113_142053.jpg (416.45 KiB) Viewed 367 times

Mocking up a bit more

[Chambers]

As suspected plenty of space in that shell!

[Tommm]

As suspected plenty of space in that shell!

Saw off a bit of the front end back. Make sure the holes on top still align and the wires have enough space to take whatever turn they need to, while going outside.