The BSA A7-A10 Forum

Technical (Descriptive Topic Titles - Stay on Topic) => Frame => Topic started by: worntorn on 24.03. 2017 03:07

Title: Header pipe vibrates out of head
Post by: worntorn on 24.03. 2017 03:07
Is there a method to hold the header pipe secure in the head? These are new Armour Siamesed pipes, not a great fit, nonetheless they do bottom fully in the exhaust ports. The right hand pipe hasn't given any trouble but the left hand Shorty vibrates out as soon as engine revs climb above 3000. ( smooth running engine)

Glen
Title: Re: Header pipe vibrates out of head
Post by: duTch on 24.03. 2017 07:24

  waaaaay back when I had the Road Rocket, I held them in with a fairly chunky length of chain tied with a padlock, but one day a Pleeceman didn't like that idea *evil*

 Short story, On this practice rebuild, I bought a (bargain at the time *eek*) pair of stock headers (Made in England sticker-maybe Wassel *dunno*), and they kinda fitted ok, but the ends were squashed/tapered in and made it sloppy, so I stretched them out to fit ok (quite a process); all to no avail as after stuffing around I decided the bends/distance between are not compatible, so ended up cutting 30mm of the ends, which means the top radius starts too close to the flange so they also blow out....

  possible remedy; I bought a small stainless steel turnbuckle from the boat-shop, to pull them together via the finnned flanges but haven't yet used it.
 Was also thinking to use it in conjunction with some SS springs on the finned flanges.




Title: Re: Header pipe vibrates out of head
Post by: terryg on 24.03. 2017 08:00
The short pipe of the siamesed set I bought from Armours was too short at the port end. It was too many months after I bought them that I found out, so no return possible. To make the set usable I welded on about an inch extra, which I was able to cut from an old pipe. There's been no trouble since.
Title: Re: Header pipe vibrates out of head
Post by: worntorn on 25.03. 2017 21:14
Thanks for suggestions Terry and Dutch. I might first try Terry's method  since the current fit up is very poor on that left side exhaust. It comes in at an angle to the port but still manages to slide into the port, so it must be quite a bit undersized.
I'm accustomed to headers with threaded nuts holding them on and was a bit gobstruck on seeing the BSA size for size method. One positive, there are no exhaust nuts to rattle loose or strip out. On the other hand, the finned ring seems to like vibrating loose and scratching the header pipe, which is pretty much trash now anyway after falling onto the roadway!

Glen
Title: Re: Header pipe vibrates out of head
Post by: Greybeard on 25.03. 2017 21:31
Those finned rings are very flimsy. Don't overtightened!
Title: Re: Header pipe vibrates out of head
Post by: Joolstacho on 26.03. 2017 08:04
The Exhaust header to head joints were = crap.
The Exhaust header to head joints will always be = crap.
The Exhaust header to head joints are and will always be = even worse crap with siamese pipes.

Any argument?  ;)
Title: Re: Header pipe vibrates out of head
Post by: chaterlea25 on 26.03. 2017 19:15
Hi Jools
Quote
The Exhaust header to head joints are and will always be = even worse crap with siamese pipes.
*conf2* *conf2*

I fitted the stainless siamese pipes to my SR over 15 years ago, Ok they were a pig to get to fit correctly, pipe expanders and more mods
I removed it a while later to re polish once it had a layer of carbon inside, once refitted it has never budged! or leaked

I have fitted several other twin pipe setups and once bolted on solidly have not had issues ??

Am I lucky?
John
Title: Re: Header pipe vibrates out of head
Post by: Butch (cb) on 27.03. 2017 12:11
Armours pipes do generally seem to be a very poor fit on these bikes - and the A10 is hardly an exotic. The down pipes I bought from them weretoo fat to fit in the ports, and again; I came to fit mine at some point later after purchase. Their advice was that I should Dremel out my ports until they would fit. Yeah - right.
Title: Re: Header pipe vibrates out of head
Post by: JulianS on 27.03. 2017 13:03
Some years back I fitted Armours stainless siamese to my A10. Very poor fit.  The bend on the short pipe was too tight to allow the finned rose to sit square against the head and the tail end of the right side pipe kicked up at the back bringing the silencer a bit too close to the pillion footrest. It did not come with a bracket.

Your short pipe probably a bit too loose in the head. Try wrapping pipe with PTFE tap and a bit of exhaust sealant or loctite copper 5920.

Eventually found a used and very very old  stainless siamese on e bay made by T and T Tubecraft which fitted perfectly.
Title: Re: Header pipe vibrates out of head
Post by: BSARGS650 on 27.03. 2017 15:41
I have never had a correct fit of pipe from Armours, three times is enough!  And, when complaining, it's either my problem ,or, a suggested bodge!  Never ever again......Who out there in the wide world make a decent pipe that actually fits?
Title: Re: Header pipe vibrates out of head
Post by: worntorn on 27.03. 2017 17:01
Hi Jools
Quote
The Exhaust header to head joints are and will always be = even worse crap with siamese pipes.
*conf2* *conf2*

I fitted the stainless siamese pipes to my SR over 15 years ago, Ok they were a pig to get to fit correctly, pipe expanders and more mods
I removed it a while later to re polish once it had a layer of carbon inside, once refitted it has never budged! or leaked

I have fitted several other twin pipe setups and once bolted on solidly have not had issues ??

Am I lucky?
John

Its the "bolted on solidly" idea that I'm having difficulty with:-)
The long right hand pipe has an attachment to the frame which seems to be keeping the pipe in the head. The short left hand pipe has nothing holding it in other than the clamp at the y. I've tightened it fully but it isn't enough to keep the pipe in the head . It would be asking a lot of that little clamp to somehow keep the far end of the pipe in the head.
So the left hand pipe just lays there waiting to vibrate out, there's no proper fastening holding it in.

This pipe also comes in at an angle so that the finned ring sits wonky as Julian described. At least Armours is consistent with the bad fit!

Glen
Title: Re: Header pipe vibrates out of head
Post by: Joolstacho on 28.03. 2017 00:01
Yes, I should have mentioned that my system is also an Armours siamesed one. The short LH pipe enters the port at the wrong angle so makes it hard to seal.
This setup is bound to fret away at the port, particularly in alloy heads, maybe iron heads are not so much of a problem.
I've had no problems with other Armours parts.
Title: Re: Header pipe vibrates out of head
Post by: Tomcat on 28.03. 2017 10:09
I have never had a correct fit of pipe from Armours, three times is enough!  And, when complaining, it's either my problem ,or, a suggested bodge!  Never ever again......Who out there in the wide world make a decent pipe that actually fits?



I have Feked Siamese pipes on my Super Rocket, and they fitted with minor modifications. The bracket on the RHS makes no sense but probably is for an RGS.   *conf* The chrome has weird patterns on it, so am watching that with interest *eek*
To answer the original question I use and suggest Automotive Silicone as an adheasive and sealant (Loctite grey)
Title: Re: Header pipe vibrates out of head
Post by: chaterlea25 on 28.03. 2017 18:51
Hi
Jools,
My SS siamese came from Armours, and like you say the LH pipe was a *** poor fit into the head
It was a long time ago and cannot remember precicely what I did
I remember using a pipe expander, but may have then cut the pipe flush with the head and welded on a stub  *????* *????*
I had to file the crap out of the finned clamp to get it to clear the bend in the pipe *work*and sit against the head

John
Title: Re: Header pipe vibrates out of head
Post by: muskrat on 28.03. 2017 20:10
G'day Glen.
I'd use lockwire, drill a tiny hole in a fin and the cooling ring (under or inside to hide it).
Cheers
Title: Re: Header pipe vibrates out of head
Post by: JulianS on 28.03. 2017 20:31
The "power jet " silencer is shown in the 1962 brochure below.

The dealer bulletin explains what to do with the "power jet" silencer to get more power - interest only I dont think anyone makes them now!

Last photo shows improvemnets for 1963.
Title: Re: Header pipe vibrates out of head
Post by: worntorn on 28.03. 2017 22:30
Thanks for posting that Julian. I was fretting over how I would locate a new old stock "Powerjet Silencer" in order to get that elusive "3 to 4 horsepower"
It looks like there is no magic to it, just reduce restriction of silencer until ears bleed :-)

Glen
Title: Re: Header pipe vibrates out of head
Post by: coater87 on 28.03. 2017 23:29
Thanks for posting that Julian. I was fretting over how I would locate a new old stock "Powerjet Silencer" in order to get that elusive "3 to 4 horsepower"
It looks like there is no magic to it, just reduce restriction of silencer until ears bleed :-)

Glen

 Yes, remove any type of muffler (this makes it sound louder, which MUST be faster). Then put extensions on straight pipes so its not to loud for passenger.

 Put out "super secret" memo for off road racers only, and watch the glasspack mufflers fly off the shelf. *smile* If you put 2 foot long chisels right next to them in the shop, even better.

 Lee
Title: Re: Header pipe vibrates out of head
Post by: kiwipom on 28.03. 2017 23:47
hi guys, this is what I use never heard of assembling pipes dry, hope it helps, cheers
Title: Re: Header pipe vibrates out of head
Post by: worntorn on 02.04. 2017 16:37
RTV in place plus Muskrat's lock wire on the problematic rings, surely things will stay put now. I've never had to use silicone or lockwire on an exhaust. The other bikes here& previous all used threaded  connectors and gasket rings of some type to make the in head connection. If tightened when hot, they work well.The header to silencer connections just clamp up tight to seal. The dry connection make for easy removal/ replacement.

Won't be having that ease of removal with this BSA and its glued in exhaust, so hopefully there won't be a need for exhaust removal anytime soon!

Glen
Title: Re: Header pipe vibrates out of head
Post by: Greybeard on 02.04. 2017 17:24
Won't be having that ease of removal with this BSA and its glued in exhaust, so hopefully there won't be a need for exhaust removal anytime soon!
You do know that BSA stands for Bits Stuck Anywhere don't you?
Title: Re: Header pipe vibrates out of head
Post by: worntorn on 02.04. 2017 18:43
I guess all of these old bikes have their idiosyncrasies. That is why a forum like this is so helpful to those of us new to the brand.

Glen
Title: Re: Header pipe vibrates out of head
Post by: worntorn on 13.05. 2017 04:01
As mentioned in the other Siamese exhaust thread, the siliconed in pipe stayed in for 150 miles then let go.
I thought about trying the Teflon tape suggestion, but it seemed unlikely to work with this poor fitting pipe.

 Royal Enfield twins use a tie rod to hold the push fit headers in place for both Siamesed or twin pipe types. It seems a sturdy method, so I added the tie rod. Will report back after a thousand miles. The exhaust seems very solidly mounted now, I don't think there will be a repeat problem.

Glen

(https://www.a7a10.net/forum/proxy.php?request=http%3A%2F%2Fi1233.photobucket.com%2Falbums%2Fff397%2Fworntorn1%2Fth_IMG_20170512_194026_zpsptl4vw6m.jpg&hash=a9268411f110962143453a20d88b533c7915f116) (http://s1233.photobucket.com/user/worntorn1/media/IMG_20170512_194026_zpsptl4vw6m.jpg.html)
Title: Re: Header pipe vibrates out of head
Post by: duTch on 13.05. 2017 08:43

 Much like my turnbuckle idea ^^
Title: Re: Header pipe vibrates out of head
Post by: bsa-bill on 13.05. 2017 09:55
3-4 more bhp is 7 to 10% increase on a even a RGS, that's a lot surely
No I'll stick with my memory that they were for sidecar fitting  ;)