Deleted account 250319001
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Rear subframe rust
- Thread starter Nobby
- Start date
Nothing to do with the paint, it’s the undercoat, etch primers (lack of) etc 
Try using a modern. Harley all year,my 42 Yr old Shovel head I have had from new has hardly any rust,I had a late model Road King and the rust on the frame and fasteners was crap!
Powder coat is the only option in my opinion . If I ever have a new bike again. Will have parts done from new,price of bike doesn't matter,as somebody has said paint is a corner that can be cut whilst the tech equipment is priority.ACF is good but only does so much, it was never designed to combat road salt,good for the Aero industry where maintenance schedules are far more rigorous and corrosion is a big deal.
I work with German top end farm machinery,whilst the steel is a good quality the paint quality can be variable,lengthy tests have proved that the primer is not adhering correctly to the parent metal,so an etching primer is used to key to the component better. Not a fault unique to BMW is corrosion, it begins longbefore themachine is assembled .
Powder coat is the only option in my opinion . If I ever have a new bike again. Will have parts done from new,price of bike doesn't matter,as somebody has said paint is a corner that can be cut whilst the tech equipment is priority.ACF is good but only does so much, it was never designed to combat road salt,good for the Aero industry where maintenance schedules are far more rigorous and corrosion is a big deal.
I work with German top end farm machinery,whilst the steel is a good quality the paint quality can be variable,lengthy tests have proved that the primer is not adhering correctly to the parent metal,so an etching primer is used to key to the component better. Not a fault unique to BMW is corrosion, it begins longbefore themachine is assembled .
My 2011 gsa started going rusty after a year. The black paint would pretty much scrape off with a finger nail! Bmw didn’t want to know. Strangely the rust didn’t go away , so 2020 pulled the bike apart and got it zinc primed and powder coated, along with lots of other black bits.stands, brackets etc. re wrapped the wiring where the rust had made it look shite.
As I had got the arse end off, and the bike had done 50k, I did the clutch as well. Only a few more bolts to get the gearbox off.
It came off so easily… a mere tug and it popped right off the dowels.
That last sentence may not be quite true.
Tips?.. if you have never stripped the back off, take lots of pics… and then take more. Wiring runs, bracket positions, cable tie positions.
Drain the tank before you lift it off…. GSA tanks are heavy when full!!… apparently !
Replace batteries in the alarm while it is off.
Bag and label nuts and bolts and screws .
Don’t do it in a shed in the 2020 lockdown when the weather is very very warm!
If you can, do it on a bike ramp.
Do all the fluids in gearbox, FD, while it is apart. I also lubed splines on drive shaft and split the FD from swinging arm thingy…. The bolt for that is F tight!!!
I had planned to do the front brackets this year…. But couldn’t be arsed. … maybe next winter.
As I had got the arse end off, and the bike had done 50k, I did the clutch as well. Only a few more bolts to get the gearbox off.
It came off so easily… a mere tug and it popped right off the dowels.
That last sentence may not be quite true.
Tips?.. if you have never stripped the back off, take lots of pics… and then take more. Wiring runs, bracket positions, cable tie positions.
Drain the tank before you lift it off…. GSA tanks are heavy when full!!… apparently !
Replace batteries in the alarm while it is off.
Bag and label nuts and bolts and screws .
Don’t do it in a shed in the 2020 lockdown when the weather is very very warm!
If you can, do it on a bike ramp.
Do all the fluids in gearbox, FD, while it is apart. I also lubed splines on drive shaft and split the FD from swinging arm thingy…. The bolt for that is F tight!!!
I had planned to do the front brackets this year…. But couldn’t be arsed. … maybe next winter.
Teeonethousand
Registered user
Top job…well done.
Weird Bob
Registered user
Nice job.
I have the same Rallye paint scheme.
My subframe is starting to show some corrosion spots - not nearly to the extent of that. Center stand looks like crap but to be expected.
I want to powder coat the sub frame to the same blue as the main frame but can’t find a RAL code for it. I think it’s cobalt blue but the powder coated want the RAL code.
I have searched but no joy.
I have the same Rallye paint scheme.
My subframe is starting to show some corrosion spots - not nearly to the extent of that. Center stand looks like crap but to be expected.
I want to powder coat the sub frame to the same blue as the main frame but can’t find a RAL code for it. I think it’s cobalt blue but the powder coated want the RAL code.
I have searched but no joy.
yoda1965
Registered user
In 2018 my rear sub frame showed some signs of rust coming through the paint. I brought it to my local BMW dealer here in Ireland. He pointed out that my bike was out of warranty as it was a 2015.
I told him I wasn't looking to have it sorted under warranty but I was hoping for some good will from BMW.
He said he would take some photos and try to make the best case he could for me.
Anyway, BMW offered to replace the sub frame but I would have to pay for the labour. I agreed,
I paid 100 Euro. I had that bike for another year and no rust appeared in that time.
I told him I wasn't looking to have it sorted under warranty but I was hoping for some good will from BMW.
He said he would take some photos and try to make the best case he could for me.
Anyway, BMW offered to replace the sub frame but I would have to pay for the labour. I agreed,
I paid 100 Euro. I had that bike for another year and no rust appeared in that time.
There’s a bloke on YouTube who’s done his subframe in the same colour as frame I think he says what the real number is.
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