Wanted: K1200S Header pipes!

[TomL]

Have fun taking it off. Plenty of Loctite Freeze and Release on the studs.

[Phmode]

Thanks for nothing mate! What did you do with yours? Am I right in thinking that you had a problem?

Brian (big socket, long bit of scaffold pole, many hammers, loads of heat, broken studs, stud extractors, drills, Eezi-outs, new cylinder head etc. etc.  )

[Costas]

I'm starting to think about it.

[TomL]

Thanks for nothing mate! What did you do with yours? Am I right in thinking that you had a problem?

Brian (big socket, long bit of scaffold pole, many hammers, loads of heat, broken studs, stud extractors, drills, Eezi-outs, new cylinder head etc. etc.  )

Not yet but give it time

[Costas]

Yeah give it time

[Phmode]

Look what I just got!



Brian (they must have been driving through the night to get this thing to me in 3 days flat, and all for a paltry €17 )

PS Total cost was £93 as the 15% reduction hadn't been applied in the advert"

[Costas]

You've got a long night in-front of you mate , just to make them presentable.

[Phmode]

You've got a long night in-front of you mate , just to make them presentable.

I daren't polish them Costas, they are not that thick to start with and weigh almost nothing!

Brian (who was horrified to discover that, other than the studs in the cylinder head, there is ABSOLUTELY no support for the bottom of the exhaust system and he uses a trolley jack under there)

[Costas]

That is the reason for never support or lift the bike with a jack or otherwise by the pipes.
Try the Carcher first, and then some cloth with a detergent and then again some more polishing staff and then............. .

[Phmode]

So, let's get down to fitting this thing!

Being a great believer in testing before using, I filled the manifold with water and watched to see if it leaked.

Sure enough, after a few moments, water could be seen weeping from the join between the two pipes at the junction where the 4 -> 2 -> 1 enters the collector box.

This is the view from underneath showing the water weeping from the join!



The weep is from the point where the two pipes abut each other.

It is difficult to know how the joint is assembled. Is the point where the two pipes abut each other welded before the two pipes are welded into the box or are they merely pushed together and then welded around the outside.

I imagine that this is where my existing pipes are also leaking but until it stops raining, I'm not going outside to find out 

I have left the manifold with a local welder who is going to fill the join with weld. Once that is done, I will swap the pipes over and then he is going to do the original set.

Brian (who thinks Tom will be delighted to know that he is having a stainless bracket fabricated to allow the spare to be carried on tour, so if his goes in Spain we can swap em over tout suite  )

[Costas]

Will search Internet for a new type manifold complete with exhaust maybe Zard just in case . A lot of work but I guess it had to be done eventually and then you will have a spare set that is good news.

[Phmode]

A peep of sun and a feeling of Spring in the air, so it's time to get the old headers off!

But first, where is this mysterious hole that caused the MoT failure? Out with the old length of hose, fire up the motor and have a quick lie down! It didn't take long to find the leak; in exactly the same place as the 'new' one that is awaiting the hot breath of the welder's torch!

So I think we can now state quite categorically that the 'join' between the two pipes is not 'joined' at all but rather relies on the collector box to hold the two pipes together!

This is built-in obsolesence of the worst kind, penny-pinching by the designers or at the manufacturers that results in BMW making a shedload of money by selling you a new one with exactly the same in-built leak! All it takes is a little water, a little heat and a little salt and voila, one leaking manifold.

Anyway, a couple of blasts of the old Loctite and it half worked; four of the manifold nuts came off the studs and four of the studs came out with the nuts intact! Nothing like consistency is there.

So there we have it! Two manifolds with exactly the same problem.

Brian (who wonders if there is anyone out there in need of a perfectly good, leak-free manifold  )

[slparry]

I have this to do on my GT soon Brian, did you manage to do it with the rad still in place as I REALLY don't want to take it off and from what I recall there maybe just enough access?

BTW I've heard that the exhaust cat can get blocked too which forces more pressure on a week manifold too.

ISTR the K44 12's all use the same manifold and the K13GT uses the same but the K13 R or S use a different one because there's a powervalve in the pipe

[slparry]

Does anyone know anyone who can fabricate better quality ones as I'm sure they can be made for far less than the hideous price BMW charge and there must be a potential global market ?

[Phmode]

I did it with minimal stripping down Steve.

Belly-pan off, tank side panels off and tank out, assuming you are swapping the pipes as you need to get to the Oxy sensor plug. You don't need to remove the tank or tank panels if you are just changing e.g. the manifold gaskets.

Once you have gone that far it is straightforward to take off the manifold stud nuts (10mm 12 point or double hex nuts). Clearance behind the fan is interesting and next time I will take the fan off the back of the rad first as it is a great opportunity to clean out the radiator from both sides.

If you intend to take the fan off, the top right hand hex drive screw in the fan is a bugger as it is occluded by the block, but if you take off all the radiator mounting washers and clips and ease it forward, you can just about get the screw out with a pair of snipe-nosed pliers or grips. If you then file flats on the head of the screw, it is easy to get it out with a spaniard next time!

I took the manifold off with the fan in situ as I was in a hurry to beat the darkness last evening. However, with the fan out of the way, it is easier to get inside the recessed exhaust ports to clean the faces up prior to fitting new gaskets, which, if the layers separate like mine did, appear to be handed, but aren't. It would also be easier to get to the manifold nuts with the fan off.

There are loads of exhaust fabricators but their work is horrendously expensive for low volume work. They really need a jig (engine in frame is ideal) and the skill needed to get the head end flanges true and correctly oriented is not negligible. Also, the spherical end of the pipe to which the silencer connects is not a trivial piece of work.

However, having said all of that, if we can get a bunch made up somewhere that has low labour costs, then it might be affordable.

Brian (who thinks his existing headers may be beyond saving, time and Dave the welder will tell)

PS Note my modified statement (underlined above in para 5) about the gaskets.