Gen2/3 Subframe Stiffy Kit by Garauld

[A41Billy]

So I was going over my son's bike (bicycle) that he rode 3500 miles on this summer. I noticed this weight limit on hie rear-rack:

That's 25 kgs, 55.1 lbs. on a 20 lb touring bike!!

Why the hell are limited to 11 lbs (officially) on a 650 lb motorcycle?????

Maybe that is .25kg?

 

[gixxerjasen]

That's what I was thinking.

On the other hand, you gotta love this forum. Where else can you find two different vendors willing to sell you rambones and stiffys?

 

[Sportster]

all in!

 

[wabill]

I carry a Pelican case on the back when touring which is on the stout side. So, I'm also interested and will be following this thread.

 

[Hudson]

Sign me up for a set, Gary!

 

[mferriter]

So I was going over my son's bike (bicycle) that he rode 3500 miles on this summer. I noticed this weight limit on hie rear-rack:

(picture removed)

That's 25 kgs, 55.1 lbs. on a 20 lb touring bike!!

Why the hell are limited to 11 lbs (officially) on a 650 lb motorcycle?????

Maybe that is .25kg?

NO - it's 25 freaking kilograms!!!

RIDICULOUS!!!

(the period is for the MAX. abbreviation)

My son covered over 3500 miles this summer with about 45 lbs of gear on the rack.

 

[A41Billy]

So I was going over my son's bike (bicycle) that he rode 3500 miles on this summer. I noticed this weight limit on hie rear-rack:

(picture removed)

That's 25 kgs, 55.1 lbs. on a 20 lb touring bike!!

Why the hell are limited to 11 lbs (officially) on a 650 lb motorcycle?????

Maybe that is .25kg?

NO - it's 25 freaking kilograms!!!

RIDICULOUS!!!

(the period is for the MAX. abbreviation)

My son covered over 3500 miles this summer with about 45 lbs of gear on the rack.

My apologies, my sarcasm was much too subtle.

 

[rmcobb]

OK, I have the stiffy kit that I'll be installing this week. I'll post up some pics and comments about the install. Everything looks great!

 

[garauld]

Now that Randy (thanks!) has installed it (after making some minor design mods), I will make up a batch of these kits. If you want a kit, please send me a PM with your email and shipping addresses so I can work up a delivered cost.

Thanks.

 

[Queensland Ken]

PM sent, thanks!!!

 

[rmcobb]

OK, I think Gary will have a nice product for you all. After we tweaked the prototype, it fit nicely and allowed both the stock grab rail or his modified Givi rack to be used. You'll have to remove the cowling, at least one side, in order to install but that's pretty easy to do. Here are a couple pics to show you what it looks like.

This is the stiffy after I had to cut and trim the sides in order to allow the left and right sides of the cowling to fit properly.

This pic shows the stiffy installed

I had to remove the foam pieces that cushion the cowling against the subframe and just placed a piece of fuzzy side velcro in its place to provide a little protection between the plastic of the cowling. Here is a pic of the piece of foam that is glued to the cowling. This acted as enough of a interference that when the added thickness of the stiffy, it wouldn't allow the cowling to sit properly. Once you remove it, the cowling would lay properly and allow you to attach the mounting bolts.

Once everything was installed, the stock grab rail installed perfectly using the stock bolts. and a spacer Gary provided for the most rearward attach bolt. This spacer accounts for the extra thickness of the stiffy that the front two mounting bolts are now seeing. I didn't take a picture with the stock grab rail but here is a pic with the Givi mount attached.

Here is a close up of the cutout that is necessary to allow the Givi rack to attach the modified mount.

And then here is a pic showing the mount with the backrest installed.

Another shot of the backrest

All in all, I feel good about the extra support the stiffy will provide, even with the Givi rack.......I mean, isn't overkill better?

For anyone using the stock grab rail, or the popular PCA rack, the stiffy will provide some much needed strength.

Thank you Gary!!!!!

 

[bwv]

I have a question/idea.

Is there any way to sneak some support out to the third hole? (the one closest to the tail lamp)

...either via a couple of struts protruding from your vertical supports at an inward angle to beneath the third hole (compressive support), or even just a straight bar extending back from the center of your top bar crossbar back (tensile support)

I know you are not trying to recreate the whoe subframe (You'd probably make a better one than OEM if you did)... and are just adding some strength... It's just a thought. (keep in mind that I dont know what i'm talking about here and that I could overcomplicate a wet dream.)

Looking at some pics of cracked subs, it looks to me like that 3rd hole is the "end of the crowbar" that causes the failures by twisting down on the whole thing.

Please take this as constructive. I am no engineer, do not have a broken one to look at, and haven't had mine apart yet. That third hole is the one that makes me nervous when i think about putting too much stuff on my rack.

 

[someguy]

Sweet!!!!!

 

[garauld]

Is there any way to sneak some support out to the third hole? (the one closest to the tail lamp)

Unless someone else chimes in, there hasn't been any failures between the third hole and the forward two, hence I don't see a need to make the brace any more sophisticated. AFAIK, all the cracks have occurred either in the vertical ribs or the lower angled horizontal pieces. My stiffy helps to transfer the load and twisting movements around those areas - a good thing!

 

[bwv]

A good thing indeed... and it is definetly a fine piece of engineering...no doubt about that.

Again.. no criticism intended.

I didnt mean the OE part would break between the rear hole and the two forward ones, I meant that maybe you could reduce the force from the "lever effect" that weight on that third hole has on the weak area of the OE cast Al part, by passing that load to your stiffy before it gets distributed forward to that weak area.

That way we can REALLY overload our bikes

Your stiffy, as with all the other fine things you build, looks like it is very well suited to the task at hand.

Like I said... i tend to over complicate everything.

 

[oki]

Cool. It looks like it will work with the Givi SR357 rack, as well.

 

[garauld]

--- that is a Givi SR357 rack shown in post #30....but supersized...

 

[wabill]

I thought I had the FJR set up for the winter months, but thank goodness, now I have a winter mini-project.

 

[Poida-12]

Gday guys,

I've just finished repairing my subframe for the second time. I highly recommend you use one of these kits if you don't have the Givi 357. I probably would have used one if they were available at the time.

Pete

The broken subframe

The repairs, underneath

The repairs, top side

 

[garauld]

That will probably break again as it has no real reinforcement added across the fixed areas. Welding also anneals the surrounding areas (called HAZ - Heat Affected Zone) thus softening and weakening the parent metal. Curious - how much did the repair cost?