1981 GS850G preparing for road trip

[Juke Nukem]

Hi

I'm going to be 40 next year and I decided to celebrate the occasion by going on a some kind of road trip from Finland through continental Europe. Route details depend on many things like for example what will be the Covid situation in Europe in 2021... I already have a GS450 which is completely dismantled, waiting for better years. For the trip I started looking for any bike which would fit inside my minimal budget, but of course GSs had priority status. After a while I spotted a GS850G which ticked all the boxes and as a super cool detail it was exactly my age, to the month! This was clearly a sign to buy it and so I did. It's in running order and I actually went to see it by train and drove it back about 700km. Being an old and cheap bike it of course has a bunch of things to fix. I'm going to spend this remaining ~11 months trying to make it as road-worthy as possible. No restoration, nothing major, nothing expensive. Here she is:
850cover.jpg

[Big T]

Nice
Check the charging, do the maintenance and you're good to go

[Juke Nukem]

I'll use this post as a done / to be done -list and edit it as things progress.

To be done
Get a new steering column lock
Do something about the engine breathing out lots of oil
Fix minor oil leaks here and there
Fix or at least check the dodgy clutch
Fix the rear brake (other piston maybe stuck)
Replace missing engine mounting bolts
Get saddle bags
Fix fuel petcock


Done
Fixed charging system
Leaky exhaust fixed and straightened
Rear shocks upper mounting threads fixed
Another set of keys made
Leaky rear wheel valve replaced and wheel balanced
Fuse box cover acquired

[Noreg]

Hi

I'm going to be 40 next year and I decided to celebrate the occasion by going on a some kind of road trip from Finland through continental Europe. Route details depend on many things like for example what will be the Covid situation in Europe in 2021... I already have a GS450 which is completely dismantled, waiting for better years. For the trip I started looking for any bike which would fit inside my minimal budget, but of course GSs had priority status. After a while I spotted a GS850G which ticked all the boxes and as a super cool detail it was exactly my age, to the month! This was clearly a sign to buy it and so I did. It's in running order and I actually went to see it by train and drove it back about 700km. Being an old and cheap bike it of course has a bunch of things to fix. I'm going to spend this remaining ~11 months trying to make it as road-worthy as possible. No restoration, nothing major, nothing expensive. Here she is:
[ATTACH=CONFIG]61402[/ATTACH]

Where in finland are you starting from? I wouldn't mind tagging along for a portion of the ride if you start from the north, ofcourse i understand if you want to ride solo. I need a trip to Jyveskykla to visit my friend. And Ive always wanted to go to Helsinki.

I'd check the tank for rust, it sucks having your bike pouring gas out of the carbs because one got stuck from rust. And the age of the tyres (order new one way before you need them, it sucks waiting for tyres, lost way too much time waiting for mine).

Apart from that the bike looks great, Id add some mirrors though.

Is that the original exhaust? Mind me asking what you gave for it?

[Noreg]

I'll use this post as a done / to be done -list and edit it as things progress.

To be done
Make it charge
Get a new steering column lock
Do something about the engine breathing out lots of oil
Fix minor oil leaks here and there
Fix or at least check the dodgy clutch
Fix the rear brake (other piston maybe stuck)
Replace missing engine mounting bolts
Get saddle bags


Done
Leaky exhaust fixed and straightened
Rear shocks upper mounting threads fixed
Another set of keys made
Leaky rear wheel valve replaced and wheel balanced

Heh, my bike is the same age, and my rear pistons are pretty hard to move. Had to use tools and leverage to pry them apart enough to fit new brake pads and a disk.

Where does it leak oil? Mine leaks from the cam chain adjuster and used to leak from the oil filter cover (think new studs, acorn nuts and washers cured that though, testing it out tomorrow).

How did you fix the threads for the upper mounting threads? Mine is sketchy on one side.

[steve murdoch]

I love the International aspect of this site.

[Juke Nukem]

I live close to Helsinki, so the actual trip will start with a boat ride over to Estonia and then through the baltic countries etc... And yes I'm planning a solo ride. But if you decide to head over to Finland, it would be cool to do an extra trip to test the bike and drive around. I could easily justify a trip to Oulu for example and ride south from there or whatever. I was actually in Jyväskylä just a few weeks ago (by car).

The tank looks clean from the inside, but I've had a case of flooding carbs once, so probably should check again.

Mirrors I have, they were just removed to fit the bike through the narrow door to my bike shed.

The exhaust is original, but badly rusted from the inside. The baffles inside are probably gone in many places. I welded it together as I best could and hope it stays together long enough. I can find new exhausts from ebay, but they are around 400-500€ per side, so around 1000€ total. Way out of my budget.

I haven't located the oil leaks very carefully yet. Some of it was the breather hose to the air box. It breathed so much oil to the box that it leaked out. I routed a new hose to go to the ground for now, but will make some kind of catch-can system when I get to it.

I fixed the threads by welding new metal on them and filing them cylindrical, and then made new threads with a thread die.

[Juke Nukem]

Some summary posts of stuff that was done before starting the thread.

Rear tyre was leaking. Removed it and located the leak to be on the valve stem. Took it to a shop to be fixed and balanced. Baby bathtub proved to be really useful.
rear wheel.jpg

[Juke Nukem]

The threads on the upper fixing points of both rear shocks were gone. Welded new metal on them, filed down to correct diameter and made a new thread with a die. An awful job due to an awful welding macine.
thread.jpg

[Juke Nukem]

The right hand side exhaust had an innocent-looking leak in the middle and was pointing in a funny direction. Turned out to be broken in the middle. There was a broken inner tube which was almost entirely rusted away. I fabricated a new one and welded the right side back together. I removed any visible rust an coated the worst areas with a ceramic heat paint. Everything after the down tubes is rusted pretty thin and the internal baffles of the mufflers are more or less gone. The exhaust sound is nice though . Hoping the thing stays together for a few more years...
exhaust.jpg

[Juke Nukem]

Oh yeah. I tried to bleed the rear brake but couldn't get anything out of the outer side. No air but also no fluid. So I figured the outer piston must be somehow stuck (?) and the rear brake is operating only on the inner piston. The caliper is floating, so I guess it works with just one piston too.

Heh, my bike is the same age, and my rear pistons are pretty hard to move. Had to use tools and leverage to pry them apart enough to fit new brake pads and a disk.

Where does it leak oil? Mine leaks from the cam chain adjuster and used to leak from the oil filter cover (think new studs, acorn nuts and washers cured that though, testing it out tomorrow).

How did you fix the threads for the upper mounting threads? Mine is sketchy on one side.

[Grimly]

The standard caliper isn't floating - all it's doing is bending the disc.

[Juke Nukem]

The standard caliper isn't floating - all it's doing is bending the disc.

You're right, it's not floating. Don't know where I got that from.

Then I'd say the other piston isn't stuck. The break feels reasonably ok, and I can lock the rear wheel. That wouldn't happen if only other piston was pushing from the other side. Maybe the bleeding screw is just clogged or something.

[Grimly]

The rear caliper lives out of sight / out of mind and slowly gets worse, with one piston developing a laziness before the other. Only cure is a strip and replace of the seals. You'd be surprised how much dreck is in there after 40 years. Once rebuilt, they're good for another decade at least before needing any serious attention.

[Noreg]

Is the €1000 exhaust original? If I could get that for mine Id be thrilled.