Re: What did you do to or for or with your Laverda today?

I know it looks ugly but having a flat bar down to the pillion peg does heaps as a brace as well. Make it removable for when you don't want the load carrying capacity.  I made my rack easily removable as it is a bit of a horror to look at , but even then its a bloody good hour of hard wrestling to get it on and off so I don't bother now. I like the attention as well
 
Dellortoman said:
Well, we're not all miners that can buy anything new and flashy on offer :-*


Peter, I hope you don't mind a bit of constructive criticism. Here's an engineering assessment.

I'm afraid I agree with Andy. It looks about as dodgy as the racks from that ?spurious peddler of racks-to-order?.  Definitely not as good as it could be.  It actually looks like an original grab handle with a rack welded onto it.  The tube wall of those grab handles is not thick enough to support any kind of load on the rack.

It's good that you've taken the diagonal brace right back to the indicator mounting point, but not so good that you've significantly weakened that diagonal brace by putting a bend in the middle. I'll give your rack a score of 6 out of 10, and that's only because the welds look neat :D

That rack may work for a time, but will eventually fail because of insufficient strength at the rear mount, where the bending load is highest. If you bolt it to the bike, then lean on it with your body weight, it'll probably fold at the rear mounts. It's basically a cantilever beam from that point back to where the load is carried. Even with small luggage loads, fatigue will get to it eventually.

If you use it like it is, one day you?ll turn up to a rally and your camping gear will be gone. All that will be left is a couple of bits of broken tube. If you're lucky, you?ll hear it go because the indicator wires will hold it long enough for it to clatter against the mudguard as it departs.  :D

Failures can be avoided by using a much thicker-walled tube for the base loop (eg: water pipe) or by adding some reinforcing around that point (the root of the cantilever).

As you've already made it from thin-walled tube, additional reinforcing seems the simplest way forward.

If it's for a 3C which doesn't have a hinged seat, you could simply add a diagonal brace from the top of the grab handle loop back to the forward mount where it bolts to the shock absorber mount.

If it's a 3CL with hinged seat that precludes bracing above the grab-handle loop, I?ve re-attached your picture showing some suggested bracing below the existing grab handle tube. Use some more of your tube to make up a lower frame member and brace it back to the upper tube with some gussets. If you use flat plate (aligned along the tube, not across) for the gussets, they'll provide additional stiffness. The indicator mount can be incorporated in a gusset. The lower tube will be in compression load. Therefore any bends (such as below the indicator mount) will need to be tied back to the rest of the structure to create triangulation and prevent buckling. You?ll also need to reinforce the mounting lug where it bolts to the rear of the frame as shown in the sectional sketch. It?s OK as a mount for a grab rail, but inadequate for a luggage rack.

Some hooks for tie-down straps might also be useful.
Click to expand...
Hi Cam,
Constructive criticism always welcome, but f**k me :o :D
You are correct, it is an original grab rail with a rack welded on. (Idea was for easy interchange when not needed) Intention was only for light loads on it but reading that, if I want to use it then I'd better brace it up! Never bothered with a rack on the Lav before so just thought I'd create a bit more room.
Always used to have home made racks on my bikes back in the '70's but have to admit had a whole back yard full of various bits of metal to make em from ground up and the material we used was always much stronger than this.
I had been concerned about it's strength being quite light pipe, but had thought the brace back to indicator point would be ok. By the way, I didn't bend the diagonal brace bar, it was part of a frame of one of those small fold up chairs!
Anyway, I do appreciate your thoughts and what you have said makes sense. I will consider my next move :)
 
Harsh, but perhaps correct (I'm not an engee or a chippy) ............ looks good Peter, paint it black and smile.
Let's see who has the last laugh when you get down to Sydney with it intacted.  8)
If it doesn't make it back to FNQ, don't tell anyone.  ;)



 
chrisk said:
Don't forget the flack, the last bloke that never made it back to Townsville, got on here, and still does.
It's not fair, is it AndyW.  :D
Click to expand...
:LOL: Yeh, it'd be good to make it one way at least :o
(The rack might go on the back burner for now - other priorities)
 
Shajota said:
Hi Cam,

I had been concerned about it's strength being quite light pipe, but had thought the brace back to indicator point would be ok. By the way, I didn't bend the diagonal brace bar, it was part of a frame of one of those small fold up chairs!

Anyway, I do appreciate your thoughts and what you have said makes sense. I will consider my next move :)
Click to expand...

(hahaha)
 
chrisk said:
Don't forget the flack, the last bloke that never made it back to Townsville, got on here, and still does.
It's not fair, is it AndyW.  :D
Click to expand...


I gave up on Townsville altogether it was too far away even from itself... (banghead)
 
Not today, but I recently went to start the 750. Turned on the taps, the choke and the key, lights came on, stabbed the starter and nothing. Dash lights go full off. Heard a faint "click" somewhere from within the side covers and all went dead.
Checked the fuses, all were fine.
Looked for my multimeter, had previously loaned it out so no battery check.
Texted IAG, he suggested I check the ground connections to see if it was loose.

For fucks sake, it sure was. So I went for a ride because it's like 50 degrees in Chicago lately.

Just a note, check your ground connections every now and then and be happy more often.

;)
 
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