K75 Replacement Radiator

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Tony the Skin
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K75 Replacement Radiator

Postby Tony the Skin » Fri Sep 07, 2018 10:27 am

My radiator is leaking. Does anyone know of any aftermarket replacements of good quality?. Nothing shown on the main spares sites in the UK except secondhand ones. I don't want to go down that route as they are about 25 to 30 years old.
BMW R75/5
BMW R90/S
BMW R75/7
BMW K75 Sprint
BMW R1200 RS LC
Harleys
MZ 251
Suzuki GT750A

Membership No. 672

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Galactic Greyhound
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Re: K75 Replacement Radiator

Postby Galactic Greyhound » Fri Sep 07, 2018 12:19 pm

Hi Tony,

Consider taking the radiator to a radiator repair shop - likely cheaper than buying new/used.

They will dunk it in a tank of water while pressurising it with air.
This will show up existing leaks and any forthcoming leaks due to weaknesses depending on the air pressure used.

The usual method of repair is to solder the leak or, if the whole tube is bad, to seal off the tube.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" - It works!

Tony the Skin
Club Member 13
Posts: 637
Joined: Mon Jun 02, 2014 11:38 am
Country of Residence: England
Location: Bury

Re: K75 Replacement Radiator

Postby Tony the Skin » Fri Sep 07, 2018 11:07 pm

Thanks for that. That might be my only choice. Given the custom scene I thought that there would be many options
BMW R75/5
BMW R90/S
BMW R75/7
BMW K75 Sprint
BMW R1200 RS LC
Harleys
MZ 251
Suzuki GT750A

Membership No. 672

Bill Smithson
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Re: K75 Replacement Radiator

Postby Bill Smithson » Sat Sep 08, 2018 10:34 am

The usual method of repair is to solder the leak or, if the whole tube is bad, to seal off the tube.
That brings back a lot of memories!
I started repairing Army vehicle radiators in the deserts of Egypt many years ago on active service. They were a lot easier to deal with than modern radiators with the flimsy wafer construction used on later cars.
Whatever you do Tony, don't be tempted to empty a tin of mustard powder in the radiator to seal it - you'll ruin it.

Tony the Skin
Club Member 13
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Joined: Mon Jun 02, 2014 11:38 am
Country of Residence: England
Location: Bury

Re: K75 Replacement Radiator

Postby Tony the Skin » Mon Sep 10, 2018 9:03 am

I will resist the Colmans Bill. Were you in Suez?
BMW R75/5
BMW R90/S
BMW R75/7
BMW K75 Sprint
BMW R1200 RS LC
Harleys
MZ 251
Suzuki GT750A

Membership No. 672

Bill Smithson
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Posts: 876
Joined: Wed May 24, 2006 11:20 pm
Country of Residence: England
Location: Kendal

Re: K75 Replacement Radiator

Postby Bill Smithson » Mon Sep 10, 2018 10:29 am

I will resist the Colmans Bill. Were you in Suez?
Hi Tony,
Yes I was there and it took just over 50 years for the 'forgotten army' to get official recognition by way of campaign medals.
http://www.suezveteransassociation.org.uk/medal.html

Tony the Skin
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Joined: Mon Jun 02, 2014 11:38 am
Country of Residence: England
Location: Bury

Re: K75 Replacement Radiator

Postby Tony the Skin » Mon Sep 10, 2018 9:57 pm

Update: I took it to a radiator repair place but they said it is beyond repair so it will have to be a replacement job. I will see what the options are
BMW R75/5
BMW R90/S
BMW R75/7
BMW K75 Sprint
BMW R1200 RS LC
Harleys
MZ 251
Suzuki GT750A

Membership No. 672

Bill Smithson
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Posts: 876
Joined: Wed May 24, 2006 11:20 pm
Country of Residence: England
Location: Kendal

Re: K75 Replacement Radiator

Postby Bill Smithson » Tue Sep 11, 2018 8:32 am

Update: I took it to a radiator repair place but they said it is beyond repair so it will have to be a replacement job. I will see what the options are
How many places is it leaking from and where ?
There's one for sale at the dealer listed below. I've dealt with Ian and he's a genuine guy.
Church Stretton Motorcycle Service Centre
Ian Forbes
Crossways
Church Stretton
Shropshire
SY66PG
United Kingdom
https://www.ebay.co.uk/itm/111594712045

Mjolinor
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Location: Burnley

Re: K75 Replacement Radiator

Postby Mjolinor » Tue Sep 11, 2018 10:47 am

I have not done one for a while but a re-core should not cost you much more than that and you could probably go for a copper core.

There is no rocket science here, find a core that can be made to fit and fit it.

Are they plastic tanks?
Are the tanks OK?

If the tanks are OK it will re-core.
Last edited by Mjolinor on Tue Sep 11, 2018 10:52 am, edited 1 time in total.

Mjolinor
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Re: K75 Replacement Radiator

Postby Mjolinor » Tue Sep 11, 2018 10:49 am


Tony the Skin
Club Member 13
Posts: 637
Joined: Mon Jun 02, 2014 11:38 am
Country of Residence: England
Location: Bury

Re: K75 Replacement Radiator

Postby Tony the Skin » Tue Sep 11, 2018 11:22 pm

It is the bottom of the radiator that has gone.
BMW R75/5
BMW R90/S
BMW R75/7
BMW K75 Sprint
BMW R1200 RS LC
Harleys
MZ 251
Suzuki GT750A

Membership No. 672


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