The BSA A7-A10 Forum

Technical => Frame => Topic started by: chaterlea25 on 09.07. 2010 21:35

Title: "Head Steady"
Post by: chaterlea25 on 09.07. 2010 21:35
Hi All
As discussed on another topic where I voiced my opinion about the original BSA head steady being responsible for rockerbox gasket oil leaks,
Here are some photos of the making up of my compressed rubber bush head steady
I made one today to fit to the SR (moneypit!!) thats been taking up the workshop bench for far too long
the good news on that front is that I fired it up yesterday and it sounds very sweet!!!

The piece of rubber tubing in the photos proved too hard to press the inner bush through in the vice so I used some 1/8th reinforced rubber gasket material rolled up into a tube!!
The bullet shaped piece acts as a "lead in" for the inner bush as its pressed in through the rubber

As for dimensions,
the inner bush is a tight fit length ways between the rockerbox brackets. 1.5in.
I used a piece of 12mm round bar drilled through 8mm
A piece of heavy wall stainless tubing from the odds and sods bin formed the outer 21.5mm od and bored to 17mm inside dia. a shade shorter than the inner bush 0.5mm or so

Two pieces of 20x3mm  flat SS are cut and shaped to fit around the outer bush
I wrapped the inner bush with some tape to temporarily fit it to the outer and then to the rockerbox brackets
offer up the flats and mark the hole positions from the frame mount,
drill the flats 8mm
I used a piece of 8mm threaded stud and 4 nuts to position the flats parallel and 1in. apart to simulate the frame mount
Then the shaped ends are welded to the outer bush
Last fit the bullet to the inner bush and the rubber tube to the outer, lubricate with silicone spray and press the inner into place!!
The rubber will squidge out at the ends a bit, trim this offwith a sharp knife

Cheers
John O R









Title: Re: "Head Steady"
Post by: muskrat on 09.07. 2010 22:12
Thanks John, that looks very neat, and is how I pictured it in my mind.
 I mentioned it to a friend and he looked at me in horror, saying most manufacturers solid mount for a reason. I argued that any frame flex would also have detrimental effects.
 Last weekend I removed the jack bolt from between the frame and rocker box and run with the std steady. A lot more vibration felt, so much so that riding at 3200 rpm (60 mph) was painful. But at 3700 (70 mph) and up it smoothed right out. The following rider (above) was left behind.
 Thanks again for your time to post this and the damper.
Cheers
Title: Re: "Head Steady"
Post by: JohnH on 14.07. 2010 23:13
John
Thanks for posting the information - it looks very professional.
John
Title: Re: "Head Steady"
Post by: wilko on 16.07. 2010 00:31
Without wishing to offend, rubber mounting a head steady would seem to defeat the purpose, allowing give in them. You would have to rubbe rmount like a Commando to make it effective!
Title: Re: "Head Steady"
Post by: RichardL on 16.07. 2010 04:14
Well, I'm not trying to read John's mind, but here is my explanation. John's steady, like the original, does a good job of stopping low-frequency, large-excursion vibrations, that is, those that would be most damaging. High-frequency, small-excursion vibrations are damped in the circumferencial rubber of the mount rather than transmitted to the joint between the head and the rocker box.

Does that about say it John?

Richard L.
Title: Re: "Head Steady"
Post by: Mosin on 16.07. 2010 10:25
I don't know too much about the mechanics of vibration frequencies etc, but what I do know is this: When I bought my Shooting Star it did not have a head steady fitted at all. I rode it like this for a while and the rocker box never leaked a drop. I have now fitted a head steady and I cannot seem to keep my rocker box oiltight for love nor money.

Make of that what you will.
Title: Re: "Head Steady"
Post by: A10Boy on 16.07. 2010 10:56
That seems to me to be a very professional set up.

However, I can't help thinking there must be a conflict when you have the lower engine bolted solid to the frame and the top end able to move around on rubbers. The original head steady wasn't hugely solid so must have allowed for some small flexing or is it thought that it moved the rocker box and made it leak? If so, how come there are millions of engines on the original set up that don't leak from the rocker box? I would have thought that the leaking ones were more likely to be caused by warped gasket faces or iffy banjos or something. My concern is that this rubber jobbie is well made but could be hiding the real problem.

 *conf*
Title: Re: "Head Steady"
Post by: muskrat on 16.07. 2010 11:03
I like your reasoning Richard and I can see Wilko's concern, and it would be justified if it was soft rubber. A high density rubber should give the desired affect.
I know where your coming from Mosin. My plunger never leaks from the top, everywhere else but not the top.
BTW my horrible vibes were caused by the rear engine mount bolts. 1 missing, 1 loose !!! *eek*
Cheers
PS maybe this is why I can't concentrate in the shed.
Title: Re: "Head Steady"
Post by: Brian on 16.07. 2010 11:09
A 1953 B33, how do I know ????? Oh and a woman as well !!!!!!!!!!!!!!!!!!!!!!
Title: Re: "Head Steady"
Post by: A10Boy on 16.07. 2010 11:12
She should have that carb up on the bench really...
Title: Re: "Head Steady"
Post by: muskrat on 16.07. 2010 11:24
Sorry Brian, just saw it on MIE and had to use it.
Cheers
Title: Re: "Head Steady"
Post by: terryk on 16.07. 2010 14:08
Brain you know because of the tank badges. They were only in 1953.
Title: Re: "Head Steady"
Post by: terryk on 16.07. 2010 14:12
But 1953 should have speedo in the cowl and enclosed type rear number plate. So it might be just a 53 tank? Or am I wrong?
Title: Re: "Head Steady"
Post by: MG on 16.07. 2010 20:16
Err, I'd rather like to know the girl's year of manufacture (hard to tell, can't see no badges  *grins* *whistle*)
A phone number wouldn't hurt either, I think my carbies need some attention as well...  *smile*
Title: Re: "Head Steady"
Post by: Brian on 16.07. 2010 23:30
Your right Terry, the tank badges, kneepads and the toolbox say 53' but it should have the cowl so must be a bitsa. As for it being a B33 and not a B31, the size of the hole shows that.......
Title: Re: "Head Steady"
Post by: chaterlea25 on 16.07. 2010 23:42
Hi All
Talk about a thread hijack, *smile*

Yes, Richard L , very well put,



A10Boy, says,
"how come there are millions of engines on the original set up that don't leak from the rocker box? "

If there are I havnt seen them!!!!! neither have most of the forum by the looks of things ;)

The original is called a head "steady" not a head mounting!!
so the logic of locking the head/rockerbox in one place was not the designers intent????

The head rockerbox faces are very thin and often damaged, my head steady design will not fix these ???? ????

I have the first one I made fitted to my own SR for the last 8 years and well over 10k miles (speedo's another story *sad2*)
and there have been no issues with it, neither have there been on the other A10's I have fitted them to

"Each unto his own" But it works for me *smile* *smile*

Cheers
John O R

Title: Re: "Head Steady"
Post by: RichardL on 20.06. 2012 22:26
John,

After almost 2 years, what is the status of rockerbox leaks whilst using your bespoke head steady. This is a current topic in another thread, but I thought posting here might draw others to see your excellent design (not to mention a photo posted by Muskrat).

Richard L.
Title: Re: "Head Steady"
Post by: chaterlea25 on 20.06. 2012 22:41
Hi Richard
No problems here (except for the state of the country  *sad2* *sad2*)
Head steadies are working fine  *smile*

Regards
John O R
Title: Re: "Head Steady"
Post by: duTch on 21.06. 2012 01:30
 I've read bits of posts about this issue and may have missed some, but the 'head steady' on the plungers bolts on under the front R/box bolts actually 'in' the head (I've alloy head so could be wrong?), whereas the after '55(?) bolt on top of the Rocker box.
      I would think that would produce differing types of support, the later idea would allow the joint between the box and head to 'slip' laterally with vibration, would it not, whereas the early ones would hold the whole show??

 Just a thought, duTch
Title: Re: "Head Steady"
Post by: Brian on 21.06. 2012 04:18
Seems to be a bit of difference in opinion here but I say good on you John for trying something different. I've tried lots of different things (improvements?) over the years and some work and some dont. You dont know until you  try.

I agree that your mod will loose a slight amount of rigidity but I cant see it being enough to affect anything.

One small thing that probably needs clearing up is the head steady does not bolt to the rocker box. It is held by the four bolts that go through the rocker box, you could say the rocker box is "through bolted". Those four bolts thread into the head, not the rocker box.
Title: Re: "Head Steady"
Post by: duTch on 21.06. 2012 07:35
 
  Sorry slight oversight on my part, and I guess they(through-bolts) should be reasonably 'snug-ish?', I hadn't put a lot of thought in to it, was thinking more of the principle at at the time.
 cheers
Title: Re: "Head Steady"
Post by: RichardL on 22.10. 2014 23:55
I always admired John's idea for an improved head steady and finally got around to making one myself according to John's design. $5.00 in materials (with a lot of left-over steel strap) and a bit of labor and it was done. Even though my father was a refrigeration contractor and pipe-fitter, I never became a good welder, in fact, right now I'd say I'm a lousy welder using a lousy welder ("it's a poor workman who blames his tools"). No way was I going to let you guys see this thing before a lot a grinding followed by painting, and still its rough, but it's installed and fits well. In the picture it's sitting on a piece of the rubber gasket material I used to make the bush. It was a bit too thick, so thinned it down using an orbital sander. Not having a lathe, I bought the center tube from the local hardware store, really, about the perfect size, except I wanted a closer fit around the bolt, so I lined the sleeve with some shim material.

I am going to name this personal bodge "The CJ Special" (for Chaterlea John). I know it's not up to his quality of craft, but it takes all kinds.

Richard L. 
Title: Re: "Head Steady"
Post by: muskrat on 23.10. 2014 01:09
Well done Richard. We're on par when it comes to welding, put two sticks worth on then grind one off. *work*
Let us know if you notice any difference in the vibes and rocker box leaks.
Cheers
Title: Re: "Head Steady"
Post by: denis on 23.10. 2014 08:52
Hi all,

Good work Chaterlea! it looks neat.
Head steadies on my rigid frame are from the front of the cylinder to the frame between the exhausts, so they are more like cylinders steadies really, and I'm not sure these little flat ended tubes would steady much,  *conf*. 
I don't have anything on the top, should I?

Cool pic Muskrat!  ...My wife won't come anywhere near the shed, i don't understand; money pits should get along well  *whistle*, i don't understand how these cameramen manage!

Cheers, Denis 

Title: Re: "Head Steady"
Post by: muskrat on 23.10. 2014 09:34
G'day denis. Both the rigid and plungers are done that way and I find they leak LESS from the r/box.
I think the s/a steady is to ward against fore and aft movement produced by the thrust forces of the piston and un-balance of the crank at mid stroke.
Cheers
Title: Re: "Head Steady"
Post by: Topdad on 23.10. 2014 10:31
Hi Denis, I once started one of my previous "A"s without the head steady fitted ,I didn't/couldn't run it for long the motor moved in a terrifying manner ,thought it was going to rip itself out of the frame so they do work, honest ,BobH.
Title: Re: "Head Steady"
Post by: chaterlea25 on 23.10. 2014 21:59
Hi All,
Quote
I am going to name this personal bodge "The CJ Special" (for Chaterlea John).

LOL  *smile* *smile*
I await the results and the "royalty" check in the post   *smile* *smile*

Seriously Richard I hope it works for your bike

I used to be able to weld quite well when I was younger, I dont know if its failing eyesight or issues with hand eye coordination that is a result  of headbutting the tarmac off my Morini   *conf*
But now it takes a lot of concentration to get the weld in the correct place not a 1/4 inch away from where it should be  *????* *????* *????*

Cheers
John
Title: Re: "Head Steady"
Post by: terryg on 24.10. 2014 07:49
Royalty cheque?  Well, I was thinking I would try it too!

As for the welding, I think in my case it's practice, practice, practice.  No substitute for 'keeping one's hand in'.  I find something similar with spraying, too.
Title: Re: "Head Steady"
Post by: duTch on 24.10. 2014 10:23

 well I don't wish to turn this into a welding thread, but I've found the value in 'Auto- Darkening' helmets- yes plural, don't leave it out in the rain, not something that happens often round here, but can catch one out if not prepared *eek*

 The other thing about welding, I hate it when the splatters get between my toes on the best run i'm doing all day..... *ex* *ex*
 Yes, I've been doing some lately *smile*
Title: Re: "Head Steady"
Post by: BSA_54A10 on 24.10. 2014 11:11
Well done Richard. We're on par when it comes to welding, put two sticks worth on then grind one off. *work*
Let us know if you notice any difference in the vibes and rocker box leaks.
Cheers

You really need to start with Oxy so you learn to master the puddle.
One you have done that then you have a good feel for how molten metal flows and will find stick welding a lot easier.
Title: Re: "Head Steady"
Post by: muskrat on 24.10. 2014 11:26
I was good at it 35 years ago when both eyes worked. Blind in the right and only 70% in the left now. And I'm deaf in the left ear to boot. You too can have a body like mine with 53 years of abuse. *problem*
Title: Re: "Head Steady"
Post by: Greybeard on 24.10. 2014 13:09
The other thing about welding, I hate it when the splatters get between my toes on the best run i'm doing all day....
Ah yes, I remember MIG welding cars on the hoist above me when I was a motor mechanic. A spit would go down the front of my overalls and burn whatever it touched on the way down. Such fun!  *angry*
Title: Re: "Head Steady"
Post by: RichardL on 24.10. 2014 13:55
 You really need to start with Oxy so you learn to master the puddle.
Once you have done that then you have a good feel for how molten metal flows and will find stick welding a lot easier.
[/quote]

Yep. I started with oxy-acetylene and moved on to stick. No shortage of either of those in a pipe-fitter's shop. I could do it, but it's not like I could put two pieces of 8" pipe together that would hold steam. That was before the days of Mig welders. Now I'm almost useless with my cheap no-gas mig welder. In honesty, I don't practice enough to know how good, or bad, my welder is. I do have an auto-darkening hood and I'm sure it's a big part of why my welds work at all.

[On a side note, one thing I loved to do in my dad's shop, when I was about 13, was to play with the large quantity of mercury he kept around for servicing mercury switches in thermostats (and other uses, I suppose). After playing around with that, I was happy to go unload the shipments of transite (asbestos) pipe being delivered to the shop.]

Richard L.

P.S. I understand that one side affect of handling mercury is the lifelong inability to put things into few words.
Title: Re: "Head Steady"
Post by: Greybeard on 24.10. 2014 14:09

...when I was about 13, was to play with the large quantity of mercury he kept around for servicing mercury switches in thermostats (and other uses, I suppose). After playing around with that, I was happy to go unload the shipments of transite (asbestos) pipe being delivered to the shop.]

I also played with mercury when I was young. Someone had dumped some mercury tilt switches near our house. I cracked open the glass envelopes to get the gorgeous silver stuff out! It feels wonderful in your hand!
Being a motor mechanic between 1969 and 1979 I must have inhaled loads of asbestos dust from blowing out brake drums, including a fleet of AEC lorries.  I'm not dead yet. *countdown*
Title: Re: "Head Steady"
Post by: Topdad on 24.10. 2014 16:49
Yes gb and Richard ,health and safety have moved us on abit thank god for some things . One of my neighbours ,a great old guy ex bus fitter succumbed to asbestos about 5 yrs ago same reason blowing out brakes with an airline .I've never mastered welding  ,spoilt really cos all my mates were time served welders courtesy of camell Lairds the shipbuilders they could weld s**t to s**t .Remember once one of them offered to weld up my Jags exhaust asked the local garage if he could use there set to be told by the "knowledgeable" owner that it was specialist gear not for amatuers he cast a quick look over it asked him why it was set up to weld 18"butts then presently gave him a lesson in welding on my box ,the expression on the bosses face was wonderful,really do wish I'd learnt now ,regards BobH
Title: Re: "Head Steady"
Post by: Pim on 24.10. 2014 23:48
Hey guys,

sorry for hijacking this thread, but I was always wondering what that mounting bracket on the engine was for. Obviously I linked them to the slot on the frame but lacking a u shaped mounting piece for it i thought nothing of it at the time. Now you got me a bit scared in retrospect(if that's possible) because I've ridden the thing without it.

I have two questions, was the bike originally sold with the engine mounted at to top to the frame with a rigid mount?
and if so is the flex produced by the heat of the engine absorbed by the mount because it's fitted under quite an angle?

Below a pic of my lack of mount, looks like one of the bolts go trough into the cylinder so that should prevent leakage by vibration? (big emphasis on should *roll*)
Title: Re: "Head Steady"
Post by: kiwipom on 25.10. 2014 07:14
hi guys, yeah used Mercury in the not so old days in a`U` Tube manometer to measure gas pressure still got some in a container, now we use a digital manometer which is a lot more user friendly,cheers
Title: Re: "Head Steady"
Post by: duTch on 25.10. 2014 09:14

 Hey Pim, if it's any consolation I never had anything connected to mine on my first A10 RR either. That was in the seventies, is that retro enough...??
 Mind you my life revolved around keeping it going so I could earn a dollar to keep it going.... *conf*

 Also, I know the photo title says 'don't ask'..... so I won't......... but if you don't explain the plastic bottle, don't check the mail either.... *smile*
Title: Re: "Head Steady"
Post by: Pim on 25.10. 2014 09:28
It's Spa water dutch, very curing.

Actually I'm trying to pick fruits of labor, hard labor. This was at the time when I just had the frame powder coated, and bolted all the bare essentials on to the frame. So the bottle is acting as an fuel tank while the original one was drying it's paint I believe. This day was the first time I started the bike after doing lots of work before even knowing if it would run. And it did *smile*. Fruits picked i could go back to work adding other parts with renewed enthusiasm.

But in general the motor is fixed to the frame there? I'll have to weld me an mount than *good3*
 
Cheers.
Title: Re: "Head Steady"
Post by: chaterlea25 on 25.10. 2014 21:36
Hi Pim,
Quote

I have two questions, was the bike originally sold with the engine mounted at to top to the frame with a rigid mount?
and if so is the flex produced by the heat of the engine absorbed by the mount because it's fitted under quite an angle?
Yes and Yes,
The original mounting is two flat strips and a spacing tube between the brackets on the rockerbox
Other ends of the strips are boled to the lug under the top tube

Quote
But in general the motor is fixed to the frame there? I'll have to weld me an mount than *good3*
Not sure what you are on about?????

John
Title: Re: "Head Steady"
Post by: morris on 25.10. 2014 23:05
Below a pic of my lack of mount

Pim, your mount isn't missing. It's right there underneath the "Spa" bottle on the underside of the top tube.
The head steady is basically two strips of metal running up and backwards from the rocker box brackets to the frame.
Peter's got a kit on his website; http://pcb.shopfactory.com/contents/nl/d62.html#p959
Here's a pic of mine;
Title: Re: "Head Steady"
Post by: Pim on 26.10. 2014 01:12
Hey John, sorry for the gibberish,  it's  my dutch trying to get trough:)

What i meant was that that in general the engine (in dutch engine = motor) is fixed to the frame with the rockerbox mount.

And morris thank you, clear as ever.
I do like the idea of some sort of shockabsorber/stress reliever with the expantion of the cylinder head and all. Because technically when the engine expands en retracts after every heat cycle, it has the potential of unscrewing the bolts, or it puts force on the rockerboxes. Id rather prevent both.

Title: Re: "Head Steady"
Post by: chaterlea25 on 26.10. 2014 13:16
HI Pim,
Quote
it has the potential of unscrewing the bolts, or it puts force on the rockerboxes. Id rather prevent both.
My original reason for making the "flexible mounting" was to reduce or eliminate those issues and  oil leaks
12 years on, and many km's//miles no issues with it on my bike or several more that I did the same to  *smile* *smile*

Apparently, with "Gold Star" models they give more power and less problems if the head steady is not fitted ???

My Ariel all alloy single HT5 which is set up for road use vibrates a lot at higher rpm, I have often considered adding a similar head steady to see if it would help  *????* *????*
So many projects and not enough time  *sad2* *sad2*

John