Ontic's 1981 R80G/S build-up thread

Hi mate ... the Thermite cases are 40 l each . They are really too big,especially too wide , but everything else out there was too small .The lids in the Thermite cases are good solid stainless trays that would be easy to rig as tool trays or tables .

I have a decent set of small BMW plastic cases but they are good for lunch and light wet weathers only .

Locking ? I couldn't come up with a quick and easy method and quite frankly those two hand wheels are very easy to reach from above .The cases have lock points outside .I forgot to mention that the main advantage of HDPE is that it doesn't rust ,it doesn't rattle ,it's light , strong and cheap .Apart from that it's no good at all ! If I could weld and bend it I'd make the whole job from the stuff .It's great .

The soft bag versus hard case debate is interesting .I can see advantages in both but I've slide the bike down the road on a big plastic box , my leg between the box and the bike . Other people call them leg breakers .

I'll keep watching your progress mate ...we await glossy pictures !

Mermite, not thermite...

...though thermite is pretty cool too.

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Good one ... my mistake !

It's been a while...

lets see,
the motobins order has all arrived.
Lots of goodies there that I won't go into yet but the most important thing for now was the siebenrock single seat- I've been waiting on this so that I finish all the subframe and luggage frame fabrication...

This will be a long and rambling couple of posts- Fair warning


Honestly, I would have preferred the black, but motobins don't carrry the black, so hopefully this colour warms on me.
very nice seat, kinda firm but the foam feels like good quality and combined with a sheepskin it is going to be very comfortable... we all know the seats but heres the seat before I.... molested it.


with my big tank the seat would not fit all that well- so as wrong as it felt I opened it up and removed some foam from the front- luckily not too much had to be removed so that the cover would require altering.

Next was to figure out how I was going to mount it and secure it without the stock G/SPD luggage rack- ie, by making my own luggage rack (of sorts) that also had some other features. Not having seen how the stock G/SPD luggage rack solves the mounting/locking and weight supporting issue I just set out to 'engineer':huh my own solution.

A complication of my life at the moment (that I won't go into) is that this bike may be required to be used for two-up touring if I go OS late next year- maybe, maybe not- but at the least if it wasn't going to be used two-up all the time I would want the capability to double people on occasion- but I am not a fan of the stock double seat and am simply not comfortable without my single seat (I've got a single seat on the 90/6 too).
So, along with my single seat, I wanted to have the capacity to use and easily remove a rear single pillion seat.

Sounds easy huh?

Now, lets fast forward through 2 full days of shed tinkering, with lots of metal cutting, sparks flying and argon flowing...
First go around I made some beautiful forward brackets on the seat frame but drilled them a tad wrong so that the seat was a litte off centre and I just couldn't accept it- so late at night I tried re-drilling the holes and of course I moved the holes the wrong way... the seat was now more off centre and now my brackets were screwed. Next day I had to cut them off and start again...
Anyway, that is all an excuse for why it looks a bit messy up the front there.
We'll just call those extra holes drainage holes OK



I need to explain a few things I guess. I tend to make things more complicated than they need to be... we'll call that 'feature rich'.
There are two parts to the frame- the main seat frame and the rear pillion single seat frame- this rear seat frame bolts into the main seat frame by some captured and welded in nuts and that front 'tongue' on the seat base keeps the rear seat under the front seat...

Oh yeah, I cut up the stock double seat to make the rear pillion single seat.
Now, it became apparant that this main seat frame was contacting a crossmember on the motorbike frame and was now load bearing. This was Ok for me, but I didn't want it riding metal on metal- so that is what those black things on the front are for. I'd already gotten furiously annoyed at the rubber bumper things on the bottom of the seat that keep falling out of the seat pan- so I wanted to make something a bit different.
I captured some more nuts in the front tube and bushed some allen head bolts with some renewable rubber bushes... fuel line of course.
What this means is that with weight on it the seat now rests evenly on these fuel line rubber bushes and the stock seat pan rubber pads (and now these stock rubber pads don't keep falling out.)


Now I hope that all looked nice and easy.... cause it wasn't!
So much fiddling and thinking and testing. But, it works. The seat locking mechanism snaps in and yet is bearing no load whatsoever. To remove the rear pillion seat requires unscrewing two allen head bolts. Simple.
The indicator crossmember is now also partially load bearing (only significantly with a pillion- so later on I've reinforced that crossmember.


The rear seat aint all that comfortable right now, but I will build up the foam a fair bit higher and a little longer at the back and it should be OK. (no big buts please)
I suppose I will match the profile to the front seat- probably just cover it in black.


next post coming up,

Now, with my seat figured out this morning I was able to return to the subframe reinforcement.
I'm an amateur welder playing on a chinsese multifunction ac/dc TIG. I've been hesitant to do the subframe myself. After mocking up my reinforcements in some random mild steel seamed tube (as posted earlier in the thread) I finished making the final ones out some seamless hydraulic tube. While the bends to get around the shock, the pannier frames and the exhaust were all tricky, the really hard bit was griding the tube to mate flush with the subframe (so that my average welding skills had a chance of successfully joining them)
My welds aren't pretty, but I'm pretty sure they are strong- today I decided to just go for it. Making the seat frame had gotten my confidence up to the point where I didn't have to think about much anymore.


first brace done- this one came out pretty good.



second brace followed- not quite as pretty, but still good. No photo it seems.

Next was figuring out pannier frame mounts- because I don't have the stock rear rack (which I believe the rear pannier frame mounts bolt to?) I had to figure something else out. The stock left pannier frame had a lot of wasted space between it and my exhaust, so I moved it in a bit.
Both stock rear mounts on the pannier frames were cut off and new ones made- these mount to the subframe on some gussets I welded onto the bottom of the indicator crossmember (gusseted becuase it is now loadbearing).

I think it worked out OK.

here's a heap of photos in no particular order,

more of the seat stuff,






because there will be a lot of weight on the back of this pillion seat I've made a support plate for it,


all bolted back together,










rear pannier frame mounts and indicator crossmember gusset- flash photography at night really makes these welds look a lot dirtier than they are




now without the pillion seat,
I may make a simple and light aluminium tray type thing that will quickly bolt on and off (in place of the pillion seat), or I might just leave it as is


shoved the fender back in for a photo, and visible also is the /6 knee pads I've had on there for a while so see if I like them






Now a question I'd welcome some opinion on- I was originally planning to weld tabs onto the subframe reinforcement and the loops of the pannier frames where they cross each other and bolt them together... sort of tie-in the subframe to the pannier frames a bit more.
you can see where they cross in both these photos- in the first photo you can see where I have ground back the powdercoat ready to weld a tab on,






However, as things are right now it feels pretty damn solid and good.
Aesthetically I'd rather not weld on tabs to my subframe reinforcements, as it kind of ruins their nice clean lines if I ever strip the bike down to 'dirt bike' mode without pannier frames.. also I wonder if it isn't a bad idea to keep the pannier frames more separate as kind of crumple zones- damaging only them in tipovers...
anyway, I'd welcome opinions on this. I'll also be making a crossover between the rear of the pannier frames so they will be pretty solid without these extra tabs.

lastly, just more of the same but this time with the stock battery covers on- YES they still fit (this was pretty tricky with the subframe reinforcments and I wasn't sure if it was going to work out)







and thats about it for tonight.
Please forgive the long rambling posts, the horribly unflattering flash photography, the messy shed and the piles of photos that are all similar to eachother.
Tomorrow I move onto the rear luggage rack which will also have a good cross brace between the rear of the pannier frames.

Cheers.
Time for bed so I can do it all over again in the morning.






P.S. Sibbo, if you read this- did you ever get a single seat or a seat pan to try to make a single seat?
You can have the front of my stock double seat if you want it. Due to cutting it a little wrong at first it is a little shorter than the G/SPD single seat but it feels like it would be long enough to work.

Hi Ontic,
mate I reckon your welding is pretty damn good ... I NEED a gas shielded welder !Your bracing is great ...overwhelming but great .It is NOT going to break bend or deflect . It's built like a tank !

Pannier to diagonal braces ...... much as I like the clan aerodynamic lines of those tubes I'd weld some matching brackets on or at the very least make up a few clamps ...two sections of 12mm x 25mm x 30mm steel or aluminium clamped together and bored to suit the brace tubes but with a stud to connect to the pannier frame.You might be surprised how much you hang on them one day half way up a mountain in Nepal.

Seat frame for the ST ? Thanks for the offer but I've got the GS 100 seat, the one that someone cut in half ...not me! But I have a cover for it and as soon as I get my very slack act together I'll make up a base frame for it with an integral rack behind . it should come up OK then I have to get the dents out of the GS100 tank ..bugger ! Do you have any idea what Ross would charge for a GS100 tank ...daggy paint but no (serious) dents ? The local panel shop quoted me $500 to knock out the dents, they're big with some wrinkles higher than the surface then paint it . I could paint on myself without any trouble but these dents are beyond me .

and ..... an excellent job !

Thanks mate,
I just got back in from the shed and had dinner,
another update next post.

I think I understand what you are saying about the extra bracing between the pannier frame and the new subframe brace- I'll think a bit more about it but after todays work it may not be required.
You mentioned built like a tank... well..

Oh thats right- I remember that story about the half seat now. I couldn't remember if you were trying to find one or not.

Ross and the 100GS tank? It was quite a while ago that I was looking into it but I think the GS tank (average condition) IF he had one at the time was going to go for $4-500-ish.
If it were me I'd be inclined to just beat it out (and in) as best you can and then fair and paint it...

better get typing the next post so I can go to bed again,

cheers,

Ok,
another long day in the shed (ahh, summer holidays)

It took me many hours to actually figure out how to proceed this morning.
I wanted to brace the rear of the pannier frames together and I wanted to make a rear luggage rack.
I played through many options of pannier frame bracing but in the desire to cut down on doubled up metal they kept leading me down the path of making the bracing as-one with the rear rack...
This is something I wanted to avoid. The stock G/S stuff anoyed me how if you wanted the single seat you needed the luggage carrier- if you wanted the pannier frames, then you needed the rear luggage rack.
I forked out $100 for the stock G/S pannier frames only to discover they were no good to me without the rear rack or heavy modification... I should have just built my own from scratch. Lesson learned.

anyway,
I googled-imaged around for inspiration... I scratched my head and dug through scrap metal.
Here is what I came up with.
That rear piece is a very beefy bit of 4.5mm stainless plate. It was a bear of a thing to bend and beat into shape.
We'll call that my rear bumper bar
Once I decided on it it began to make sense- it is just right for some unlucky bugger to grab and lift and push the bike (if the need ever arises).
With those new beefy pannier frame braces connecting to it the whole thing is rock solid. Seriously strong.







Making that took me ages.
Next was the rear rack and again I was pretty stumped. I was also very close to running out of hydraulic tube and this shortage began to decide things for me.

trying out a new (to me) technique for getting a nice bend (and the mess I have to put up with). Everything else is just bent in the woodwork vise with a hollow breaker bar but I didn't think I could get a nice 90 degree bend that way.


here is the rear rack, not finished yet


These vertical supports (my very last bits of hyrdraulic tube) aren't done yet- just sitting there to give an idea- there will probably be bends involved to get them to hug the fender a bit closer and impede less with the vision of the indicators.


I think I'll make an aluminium plate something like this, a little wider, that can be put here in solo mode,


or here in two-up mode



one more shot where you can kinda see how the rear rack attaches. Captured nuts again, inside the tube of the of the rear rack where it meets the pannier frame. A tab welded on the pannier frame for the bolt to go through. The bottom of the vertical supports will bolt to the stainless bumper. There are sharp edges, more welding to do, and all sorts of things to clean up, but that is the gist of things.



That's it for the moment.
Not sure how much I'll get done tomorrow as unfortunately I've actually got other things to do instead of locking myself in the shed.
Then I've got to get the R90 ready for its week away... it is kinda pulled apart a bit right now.

Cheers,

What size is the tubing you're using Ontic? OD and thickness? You're getting some nice bends. I like those rear braces on the pannier frames, bracing one side against the other is the way to go .

On mine I've lifted the indicators up and above my Mermite panniers. It's necessary if you want to get the bottom of the panniers far enough off the ground, you may be building smaller panniers but a couple of card board mockups might be good at this stage . Something you can hang there and look at them .

More please!

nice project...

Most of the tubing is 15mm OD and 1.5mm wall thickness. Most of this stuff especially anything critical (subframe, seat frame, etc) is the ('cold drawn' I think) seamless hydraulic tube- which is really nice stuff- but there are also a few bits of the plain old seamed mild steel tube I was mocking up with thrown in. I've beat the hell out of some of this stuff with a big hammer and it is pretty good too- I can't get the seam to split- its just not as nice as the Hydraulic stuff.
Interestingly this dimension, 15mm OD, 1.5mm WT, is exactly the same as the stock pannier frame tubing- however that stuff is soft and weak as butter- I don't what steel they used for that but it seems like it was meant to be soft and bendy:huh.
On top of this I've also used a couple of bits of thicker tubing from a /6 subframe I cut up- those rear pannier frame braces that connect to the stainless bumper are made of these and also that curve on the back of the seat frame where the seat lock is welded on.


And we are thinking along the same lines- it is coming up time for cardboard pannier mock-up. I am also thinking that I will need to move the indicators- we'll see how that goes but I'll probably plan to hang them off my rear luggage rack somehow.

One thing that has me a little confused is my tail light... it is a huge thing and doesn't match other images I see looking at stock G/S' (which seem to have much smaller tail lights). It is however a bmw Hella light and seems to perfectly fit. Maybe it was an Australian market thing?


Now, as far as 'more'- I didn't get anything done on the G/S today unfortunately- so as this is my only real thread you'll have to do with some substitue stuff.
I gave the R90 a quick oil and filter change, brake bleed, and finally made a permanent fix for my smoke escaping from the wires episode, then got things back together so it is ready to ride away for a week on Monday. I could really do with a new rear tire again but it looks like I'll just have to squeeze a bit more out of this one. There's tread on there still, you just have to lean over a bit to feel it It was getting a bit squirrely in the wet on the way back from the last ride..

Also,
out with this horrible thing


and in with this


Along with a new throttle tube and cam gear thing I got a new housing as well because a) they really weren't stupidly expensive and b) when Airbear replaced his throttle tube and cam gear the problem quickly returned as the housing itself was worn.
I can't wait to give this new throttle a good workout- that last one was seriously tainting my airhead experience and this one feels beautiful!

I've also got an oil change issue-
on my 90/6 this filter and my last filter have both looked like this when they came out:huh is that normal?


On my last oil/filter change when I first saw this I thought that I had torqued that outside nut down too hard which was why the rubber O-ring thing was split like that, so I did it a bit lighter. It happened again,
This time I actually read the manual
It asks for 30 foot pounds! I don't think I was giving near to that much- this time I did....
btw, this is the system on the /6 and the non-hinged filter I have used this time.


I thought that maybe that one of those rubber O-ring things (not really proper O-rings) on the filter had gotten stuck in the filter housing and was causing the splittage- so I took this photo because I couldn't see anything in there and I hoped that the flash and uploading to the computer would reveal it to me...
still can't see but the photo is kinda cool.


Lastly I bit the bullet and gave the garage a good tidy and clean.
It may be small, it may be packed to overflowing, even after a 3 hour clean it may look messy, and due to the christmas day flood I did have to just wash that carpet and hang it on the line for a couple of days (it was starting to really smell:eek1).
It is not much but I love it this little place
Cheers,

Sorry couldn't resist. bereahorn made me do it. Looking good, Hans!! That sucker is built like a tank!!!! By the way, got in contact with HE and pulled the trigger on a 320mm and adapter. 216 euros. Not cheap, but fair.

Thanks Jenna
bereahorn loves his popcorn doesn't he
I'm glad HE worked out for you. Is there a pic online you could link to of the rotor you are getting?
216 euro may not be cheap... but it is a lot cheaper now than it used to be

And yeah, this does seem be being built kinda strong.
I hope I am not overdoing it. When it is all complete I'll have to weigh some of these components and hopefully someone with the stock set-up can get a few weights too (if it hasn't already been done somewhere... airhead wrangler maybe??)

My thoughts so far- compared to a stock GS, with single seat and luggage rack, rear rack and pannier frames: (assumption here is that the stock stuff is made of the same gauge tube as the pannier frames and as what I am using)
subframe, with the braces and two extra gussets obviously a little bit heavier.
Seat frame/luggage rack due to a significant amount of tubing reduction on mine compared to the stock one- mine should be a fair bit lighter- and I don't imagine a little alloy plate will tip the scales too much out of my favour.
Rear rack- not finished yet, but by looking at images of the stock ones I think mine will have a bit more tubing thus will come out a bit heavier (though of more benefit for 'tank building')
Pannier frames: a little bit heavier with the addition of the rear brace to the fender and to each other, the top rear braces that I cut off and re-made should be a pretty even trade-off.
Rear fender. Heavier obviously. Quite heavy in fact. I would have used something lighter than that gauge of stainless but it was all I had on hand that would work and I didn't want to use mild steel because in that spot I could see it just getting trashed and rusting. (the bumper will be polished- I could always remake that part out of some beefy aluminium plate... hmmm... time to check out my favourite metal scrap yard again).

Aside from the seat frame/luggage rack, in comparison to stock, the only thing that could be lighter with my set-up is that unlike the stock set-up, I can run the pannier frames without having to run the rear rack (probably how I will use it most of the time for lighter touring).
In that situation I think I might come out even or possibly in front, but for a true comparison with the rear rack on as well, I rekon I've gained a bit... but a hell of a lot more strength...


cheers,

Hey mate, this is worth a read: http://largiader.com/tech/filters/

now that's a solid rear sub frame/rack... nice job!!!
a really good looking tank. much nicer than a stock PD tank.

here's what's coming in a few days... also an 81 R80G/S with factory PD tank and rear sub frame.
bike was disassembled with every seal, bearing replaced including engine and transmission internals. Pistons balanced to 1/5 gram, etc. etc. it's like starting with a zero mile bike.

wish I could claim the work, but it was done by beemerguru. who's really got an eye for details.
his projects typically take about a year to complete.

Thanks, it was a good read for a general refresher but it hasn't really answered my worries.
I am guessing that I simply wasn't torquing the big single nut on the cover down hard enough- being torqued down to the spec the Clymer calls for (30 ft-lb) aught to squash those rubber o-rings a lot flatter... and then maybe with more pressure they cook kind of flat instead of splitting like mine have?

Thanks again,
I'm really enjoying this Tig welding- I'm pretty happy with everything so far, except after a little pondering I am am not yet entirely happy with the (unfinished) rear rack and how it mounts. I won't get it finished by the time I go for holiday so by the time I get back my hydraulic tube supplier will be open again- I might start from scratch again.
I need to figure out if I am going to use this massive tail light, or get something a little smaller, as I am kind of building the rear rack around it.
I suppose this light is at least more visible with the large lens.

Does anyone with a G/S have this same tail-light as me, all the images I've seen of G/S's appear to show much smaller lights.



And yeah thanks, I really like my tank, it was a lucky buy I think. It is freakin huge, but being alloy it is light and considering I don't actually have to fill up its (claimed) 45 liters all the time, it has the capability to carry its weight a bit lower I guess...

your G/S is a beauty. Congratulations.

Gotta run,
Cheers all,

That's just depressing......

I am at this stage and I am a cheap bastard, so it will never look like yours.

Here's a quick pic of my indicators and tail light , as you say yours seem big but that's good. I made up a couple of little brackets to lift them up, it seems to work just fine.



and the obligatory pic of an ST remarkably improved by the addition of a GS100 tank .Ain't Tilly sweet ?

Great indicator alteration Sibbo,
I never thought of putting them vertically

Adios everyone
I'm off tomorrow morning for a week or so. The R90 is full of oats and ready for another good run- and I'm almost ready- still packing, feeling a bit disorganised, but it always seems to sort itself out..

I've got tomorrows route planned- a very nice run over some favourite roads and also some new (to me) roads I've been meaning to do, somewhere over 500km, with predicted temperatures somewhere over 40 degrees C (104+ for you F'rs):eek1, and a predicted very refreshing swim in the Hume Dam when I get there
Definitely a day for air-conditioning tomorrow- I'll be stopping regularly to fill up with water internally, and externally (dousing my gear in water).

Happy new year,

Lucky (well organised ) bugger !