Second Of Two Things - Grab Rail, Backrest, and Luggage Rack

[hubcapsc]

side question..... the corbin bags  once they are on are they easy to take off or are they a leave on kind of accessory?? and do you need the honda mount kit to hang them. the site does not say a whole lot..Thnaks

They're not hard to take on and off... but I can say that I take
the bags off my 1500 when changing tires, and I jack the 1800
up high enough that I don't have to take the bags off when I change
tires.

Corbin supplies the hardware, sort of "frame augmentations", very
high quality.

-Mike

[tazzzed]

thanks !!

[Jess from VA]

Bill, I like the flipped end more than the straight end, looks-wise.  

But, if I had a bag (or cooler) or something with a hard bottom I intended to use all the time, and due to it's dimensions, the inside edge would lay on or rub the back of the pillion all day on long rides, then I'd build the straight end to protect my pillion.

Now that I think about it, since you can build anything you want, it might be better to build one with a straight end, but with a 90 upturned rear lip-edge (only sheet metal thick, and like only one inch above the rack tall).  

I have the old (stupid domed curve) show chrome solo rack on my supervalk, and even though I always use multiple bungies with my big duffel bag on trips, I am always concerned that it has somehow fallen off the back of the bike (and keep looking or reaching back from time to time to make sure it's still there).  Thus, a rear edge like this L.  

The back of my Ultimate solo seat is protected by the backrest and a seat basket.

[Bill Havins]

The thing that bothered me about the mocked up rack design is the l-o-o-o-n-n-g-g horizontal line that runs almost from the front to the back (when viewed from the side of the bike).  This doesn't fit the 1800 Valkyrie at all.  I think it was Brian who said, "There are no straight lines on our Valkyries anywhere."

I revised the CAD, trying to complement the curve of the rear fender (and my Corbins) while maintaining strength and ease of manufacturing.  Please take a look and offer your thoughts.



Bill

EDIT:  updated image, adding gussets to grab rails.  Better!

[pago cruiser]

I think it looks great Bill.
The long line does not bother me ( I think it looks...efficient); and neither does the flat rack. Although matching the fender will probably look better. 

I actually prefer the flat end rack, as I always seem to end up carrying bigger things instead of smaller. And if you are carrying, say, a Craftsman tool box (yes, I have  ) , the turned up lip results in the box being point loaded; without any center support area for the bungies to exert friction force upon.  The flat rack will (if big enough) also fully support a wheel with a rotor attached - using the rotor resting on a towel on the rack.  Done that several times on my Legacy Valk. 

That said, I'm also kind of a belt and suspenders guy when it comes to bungying stuff on the bike; I never, ever use fewer than 4.   I see guys all the time with (2) bungies - which means that a single failure of a $1 bungie will probably strew whatever they have along the highway behind them.  I've seen several smallish (bike size) luggage pieces along the highways in the last several years.  Using (4), it is almost impossible that (2) bungies will fail simultaneously.

[st2sam]

Tuff choice.
Plastic plugs (6) in open ends might make it look more finished?

And - Might look better with back rest in position? (another tuff choice)

IMO - It'll be your call Bill, and in the end, the best looking luggage rack for the new Valk. 

[bscrive]

I really like the look of that rack Bill.  For me to be able to use it I would have to get new brackets that attach to the fender for my saddlebags.  Right now I have the ones that attach to the handles. 

I have to agree with Mitch.  While the turned up end looks aesthetically pleasing, the flat one would be more practical.

It would not be hard to find round black plugs, so that water would not get in and rot them from the inside out, or weld plugs on them.

I am chomping at the bit to see how a finished one would look like on our bikes.

[Wayne Basso]

I agree.  The rack looks great.  I prefer ratchet straps over bungie cords.  Less stretch, less chance of them snapping.

[tazzzed]

my 2 cents ......    you got a clean plate run with it.  The problem with all accessories is looks vs functionality.   The rack looks great with the bend at the end. not so much when it is flat.. I would go with the bend. 95 percent of the time there will be nothing on it. For the longer overnight trips or people who ride to work on the bike with a cooler or what ever back there. I would make a drop on plate that is removable, out of the same material and same basic bends that LEVELS the rack back out . When you need it it will function when you don't take plate off and have the better look. Will add 25 percent to materials and cost but will be best of both worlds ...
Fire away  tazzzz

[Bill Havins]

Mitch (and other insert rack users)

I guess the grab rails just get in the way?

In attempting to keep manufacturing costs low, and functionality high, I think the way to clear the dome of the fender (and the back of the seat) is to simply use longer spacers to hold the rack/insert up off the frame.  Thoughts?



Bill

[Bill Havins]

I need to do one more review and then I'm sending the files to the tube bender for a quote -> probably be Monday before I send the file (dimension drawings and call-outs to do yet).

I'm going with the "flat" rack.  The grab rails reflect the shape of the radiator cowls on the bike.  I think the long horizontal line of the base of the rack will disappear with the grab rails and backrest added.  Thoughts?







Bill

[pago cruiser]

Looks like a wrap to me!
Will be interesting to see what the bender guy has to say.

[st2sam]

Bill, will the backrest be a removable piece?

If yes, will you make the piece that installs in place of the seat?

It would give people the option of backrest or more luggage capacity by just removing and replacing 4 bolts.

[Bill Havins]

Bill, will the backrest be a removable piece?

If yes, will you make the piece that installs in place of the seat?....[snip]

Yes, the backrest can be removed.  I will send the design for the insert with the other design files.  It will be interesting to see the prices the bender quotes.  I'll probably make a "full set" for my bike unless the price is just too crazy.  I'll try to get quotes from several benders.

As I designed this I continued to consider how each bend relates to the next.  The proximity of one bend to the next (and the radii of the bends) determines what kind of machine has to be used to bend each piece.  The pieces in this design could actually be done with a manual bender (if the operator was careful).  I'd rather see it done on a CNC machine for accuracy and consistency.

The radii of all the bends are actually Imperial measures (as opposed to Metric).  I did this hoping the bender could use "stock" dies that he/she has on hand so I don't get quoted for "special tooling."

I have sent my first "interrogatory" to the first bender (i.e., "...do you want the CAD files or manufacturing drawings?").  We'll see what happens.

Bill

[Bill Havins]

Mitch (Mr. Engineer...),

I've begun to nitpick my design.  Do you see any need for gussets (where marked)?  This is 3/4" tubing; I anticipate using pretty thick-walled stuff given the radii of the bends.

Thanks!

Bill

[Crabballs]

Mitch (Mr. Engineer...),

I've begun to nitpick my design.  Do you see any need for gussets (where marked)?  This is 3/4" tubing; I anticipate using pretty thick-walled stuff given the radii of the bends.

Thanks!

Bill

Are these going to be aluminum or steel?

[Bill Havins]

Are these going to be aluminum or steel?

Steel.

[bscrive]

Mitch (Mr. Engineer...),

I've begun to nitpick my design.  Do you see any need for gussets (where marked)?  This is 3/4" tubing; I anticipate using pretty thick-walled stuff given the radii of the bends.

Thanks!

Bill




Nope, you have gussets on the inside and that should be more than enough....unless you want to use the handles for a lifting point...

[Bill Havins]

[snip]...unless you want to use the handles for a lifting point...[snip]

Hmmmmm....  A lifting point....  I know I go overboard sometimes (all the time?), but, well, maybe....   

[pago cruiser]

Bill - using the handles as lifting points will be fine - assuming you are referring to lifting the bike onto the center stand. Lifting from those points to put the bike into say...  a helicopter though... would have a not-happy ending. IIRC, when some military branch (Army? Marines?) was specifying a motorcycle several years ago, I remember reading that all frame members had to be able to be used as a lifting point - specifically for that purpose.  

The locations you indicated for gussetts are spot on. Applying a ??? load on the cantilevered luggage rack will want to bent the tube tight there.  

What gauge steel are you thinking?  That will determine how great the allowable stresses can be.  Putzing around the shop, Schedule 40 is usually handy - but pretty heavy.  In 3/4", Schedule 40 pipe has a wall thickness of about 0.113" - 2.9mm.  I have never seen a luggage rack with that wall thickness - usually closer to 1mm (0.04", or about 3/64").

Using something your tube bender would like - DOM tubing, maybe 3/4" x 1/16", or call it 20mm x 1.5mm wall, you would be able to carry about 50 lbs applied 6" from the rear post(s) before reaching yield stress on the (assumed) mild steel - but as you already have a gusset from the handrail weldspot to the post, call it 6" from the rear handrail termination.  That is using a safety factor of 4.  Most static steel calcs use a factor of about 2  - but not many buildings or equipment stands hit potholes and speed bumps and stand a good chance at becoming airborne - with maybe a 2g instantaneous load.

All that said (and I had to brush up a bit ) adding a gusset at that location, while beneficial,  would impact the "length" of what you could carry.  I.e., the box/whatever would hit the stern of the gusset.

Instead, I would think about adding/wrapping a second layer of steel (a half section of nominal 7/8" tube/pipe) , UNDER your 3/4" DOM, between the intersection of the hand rail and the side member, back to the maybe 1/2" past the internal 90 degree member .  To get the most strength, it would need to be edge welded continuous to reinforce that entire section.  Hope that makes sense?

This would strengthen the side members by providing a thicker wall at exactly the point of highest loading.  

Just as an example, if you were able to use 3/4" Schedule 40, you could carry almost 200 lbs with the same safety factor.  But at that point I suspect the aluminum frame would become the weakest link...

I can share the math later if you want - drop me a pm. Hope your weather is improving!

Here is a handy dandy little chart I use occasionally.  Your situation is best represented by Figure 3, with the 3/4" Schedule 40 piping.  That value (676 lbs) actually correlates well with the numbers I came up with after safety factor and some other specific project criteria are changed.

[Bill Havins]

Mitch,

You addressed exactly what I was thinking.  Excellent!  Thank you!

As you know, when a rack goes away it doesn't "just fall off."  One side goes, there's all of this dangling and swinging of the load, and then the other side goes (if it hasn't already thrown the bike and rider down).  Years ago I evaluated an executive who had crashed when his rack failed while he was on a curve.  Bad closed head injury - he was never going to work again.  Too much stuff on a metal-fatigued rack, I guess.

Okay.  I'm going to do some considering.

One of the benders in the upper midwest sent me the list of drawings he needs to estimate the cost of the prototype.  I have about 20 hours of CAD to do....

Thanks again!

Bill

[Verismo]

Good God your projects are cool, Bill.  I can tell you if I had kept the Valk I would be trying to buy a fairing and a rack from you if you had decided to produce a couple.  I think your bike is going to look super classy with all the work.  Look forward to seeing the updates!

Jason

[Bill Havins]

Thanks, Jason.

It has been pretty funny with this scooter.  I get a fair number of honks/thumbs up from people who drive by.  And a whole bunch of double-takes.  I hear, "What is that?!" a lot. 

Bill

[Avanti]

Have you looked at using the DOM with solid internal pining at each joint?

[Bill Havins]

Wow!  I finally got the design files sent to two different tube benders.  My eye is about to fall out of my head!

I am asking for quotes from two shops that have CNC equipment.  This bend could be done by hand (by someone with time, skill, and patience) but, for repeatability (and cost if there is a need to build more) CNC is the reasonable choice.  And then there is the issue of expert TIG welding - I'm not a welder.  And none of the shops around here do much other than trailer hitches and oilfield work.  I do know a fellow who is quite an expert but he has a professional business welding stainless steel - he won't consider anything else.

So, after preparing some ten print files and twelve CAD files the project is "out for quote."  And I'm going to go drink coffee, sit and watch the Blue Jays, and do nothing for about two days.

Bill

[Bill Havins]

Well, it looks like I have to do this myself.  This first estimate was $4000 to $5000.  Hmmm...  Now how much did I pay for this scooter, anyway?

[Wayne Basso]

Was that for a gold one?  Tell him you don't want to buy the shop, just the part.

[Jess from VA]

I saw that coming.  Not that bad, but bad enough. 

Call Rivco, and ask if they'd consider using your design for a limited production run for C models.  It's a long shot, considering the very limited aftermarket for the bike anyway.  But it is what they do; a limited number of high quality parts, unique to their brand.   

[Bill Havins]

Yeah, guys.  I kinda' figured that is what I would run into, too.  But ya' gotta' try.

I'll give Rivco a call.  The biggest challenge for me is the welding part - the rest I can do.  But I have a lead on a good TIG welder (not a machine, an artisan).  We'll see.

Bill

[pago cruiser]

Dang!
Once you get the bending figured out, there are some really good welders here I use.  Small shop, really good quality, always busy - and good people as well.
The best value is production kind of stuff; say, 5-10 units at a time?  Or more.
Let me know once you get something together.

[Bill Havins]

Mitch,

I'll do that.

Bill

[Bill Havins]

Sent an email to Rivco this morning.  We'll see.

Bill

Update:  Received a very courteous reply from Rivco this afternoon.  We may visit a bit; don't know for sure.

[Avanti]

Well, it looks like I have to do this myself.  This first estimate was $4000 to $5000.  Hmmm...  Now how much did I pay for this scooter, anyway?

This is exactly why I build off my own design work.
I always end up with what I want and how I want it.

[Bill Havins]

I've decided to bend the parts for the rack using jigs - I'll fabricate them myself.  Done it before to bend rectangular aluminum and it worked very well.  So, the decision's made.

Cheers!

Bill

[Avanti]

I fill the DOM full off silica sand and place the sand under several hundred pounds of capped off pressure. This supports the inner wall to keep it from collapsing.
I then cold bend it by hand using a die which supports the outer wall.
Once the bend is made I release the sand.
Remember that the material will have a memory; bending angle is different from a bent angle due to spring back.

Do not use heat with a silica sand filled capped off tube!
You will be creating a molten glass bomb!

[Crabballs]

Glad to see the rack coming along.  I have my design done and a template made.  Gave it to a friend who works in a machine shop a few months ago to get it cut and bent, but I'm still waiting.   Seems the old adage holds true, you get what you pay for.  Sometimes free just doesn't work out.  I do have to get something fabricated for this upcoming season and I won't be screwing with the "free" option.

[Bill Havins]

Making progress today - building bending jigs.

DOM tubing is due here tomorrow from www.metals4uonline.com.  They have a Dallas-area distribution center so shipping to me is quick and their prices are very reasonable.

Ordered special tooling from www.ballewsaw.com in Springfield, MO.  When we lived in Missouri I was in there about once a month.  They carry a whole bunch of woodworking and other tools, blades, and router bits that are made in the U.S.  Can't say a whole lot for their web site.  But if you have a sense of what you want a phone call gets it to you.  The two brothers who own the shop (their dad started it) are wild-and-crazy guys.  Lots of hardwood cabinetmakers in the Ozarks and Ballew sells to most of them.

I've changed the diameter of the grab rails to 25.4mm (1").  Ought to make the scale of the rack feel just right on the scooter (I hope).  All the other tubing on the rack is now 19.05mm (3/4").  The sissy bar is 9/16".

Another project in the dead of winter....

Bill

[hubcapsc]

https://steeltubeinstitute.org/drawn-over-mandrel/manufacturing-process/

-Mike "DOM tubing"

[Bill Havins]

Well, building the luggage rack and sissy bar has not gone well.  Many years ago I learned that if I am wasting material I'm doing something wrong.  It just took me one attempt at a bend on the luggage rack to figure it out this time.  So, to the drawing board (er, the computer - don't have a drafting table anymore).  Here's what I came up with:



I researched "serious" tube bending machines until I was blue in the face.  None of them did small tubing (things like 9/16", 3/4", and similar).  If they came close they cost more than I wanted to spend.

So, I studied all the DIY plans and modified what I liked.  When I have this machine built I hope to be able to accurately bend from 3/8" tubing up to and including 1-1/4" tubing.  That ought to be what I need to do the luggage rack and sissy bar of my dreams (think "Roadster").  And, next winter, I should be able to bend the mounts for the panniers that I want to build.

Today I started roughing out the 3/4" dies for the machine.  To start with (i.e., to prove to myself I can do this) I'm using 1-1/2" thick aluminum.  I had to rebuild my metal-cutting bandsaw before I started roughing out.  It went slowly, but well.  Tomorrow I'll mount the rotary table on the mill and make some chips.

Winter.  Ugh!  Gotta' stay entertained.

Bill

[pago cruiser]

Dang Bill!
That looks awesome. Looks like all the components are there.  How is it failing?
If I was to stand back at throw a rock... I would think about more leverage maybe? Or hydraulics? 

Another thought. Any custom frame builders in your neck of the woods?  That's all those guys do, all day long.  I was thinking motorcycle frames, but dune buggy guys do this a lot as well.

Glad you found something to keep occupied... It's supposed to be 80F here again tomorrow!