When I
purchased my 1985 K100RS it came complete with panniers and the BMW 22 litre
top box. After a while I realised there are shortcomings with BMW top box (apart
from small capacity), such as the way the latch operates effectively reduces
the available volume as jackets, wet gear etc. can get caught in it. The lids
also have an unfortunate habit of opening when barrelling down the road,
scattering stuff everywhere.
I looked at getting a Ventura type rack and bag but it is not compatible with
OEM panniers, at least for 8V K100RS. I decided to purchase a new top box (with
universal mounting plate) and a mounting rack from the wreckers. However I was
concerned about the ability of the fibreglass tail section to cope with the
extra load and came up with the idea of using eye and eye turnbuckles
internally in the tail section.



When I attached the ‘new’ mounting rack, I used allan head bolts and the largest
washers (OD), that would fit. On the top side I formed washers to the shape of
the tail piece as best I could.
I discarded the original mudflap retaining shackle for 2 m6 bolts approx 25mm
longer than those on the shackle and then placed 2 washers above the nyloc nuts
inside the tail piece.
Next was the fiddly part. The turnbuckle eye ends now had to be bent to shape
(using heat) to fit one end over the mudflap bolts and the other over the allan
head srews. Once all the eyes are bent to shape it was just a matter of
tightening each turnbuckle to make them tight.



eye to eye turnbuckles


mounting plate


mudflap bolts


inside tail view showing 4 turnbuckles with eyes bent and washers


finished job


I have since travelled close to 1000kms and have had no problems with the turnbuckles working loose.
Hope this helps someone.

Sorry guys (and gals?)
I have just realised my previos post should probably be in a new topic.
I don't know how/if it can be changed.

Topic split for your enjoyment!

Looks like a bit of overkill for something that is only supposed to carry 5kgs. My Givi topbox is fitted just to the tail section without any problems.

bikerboy wrote:Looks like a bit of overkill for something that is only supposed to carry 5kgs. My Givi topbox is fitted just to the tail section without any problems.

A friend had one leg of the bracket going right through the cowl.
She didn't notice that one bolt was loose and she was riding on a dirt road (kind of washboard).
This system would have prevented this incident.

I have a Givi e460 and find that with the original bracket, it's mounted way too high.
I am almost considering removing the cowl and have the top case mounted on the bike's frame.

One German store (Don't remember which one) was selling a Givi type top case with the indentation for the cowl. The only problem is that it reduces the capacity of the case.

Hi bolts,
I'm not a fan of top boxes..........but I love ingenious solutions

Paul.

bikerboy wrote:Looks like a bit of overkill for something
that is only supposed to carry 5kgs. My Givi topbox is fitted just to
the tail section without any problems.

I too have heard of cowlngs being broken - in fact I was warned against fitting a top box by my local mechanic.
Total parts cost about $25 AUD
Time to fit about 2 hours.
Time to come up with solution - too many cold ones to remeber

If only I had photos of the huge holes left in my rear cowling after the previous owner fitted a top box and had it come off.
My little rack on the back now carries no more than a sleeping bag. Or a bottle of Dr Jurds. Depending on the destination.
Maybe the Jurds should be inside the bag? hmmmm.

Seems like I found a photo post repair.
There were two massive holes (3") in the middle from some after market thing he did and the original holes were torn out.