Author Topic: "Head Steady"  (Read 5028 times)

Online chaterlea25

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"Head Steady"
« 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









1961 Super Rocket
1963 RGS (ongoing)

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Re: "Head Steady"
« Reply #1 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
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
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Offline JohnH

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Re: "Head Steady"
« Reply #2 on: 14.07. 2010 23:13 »
John
Thanks for posting the information - it looks very professional.
John
Triumph Bonneville - long gone (sadly)
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Offline wilko

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Re: "Head Steady"
« Reply #3 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!

Online RichardL

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Re: "Head Steady"
« Reply #4 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.
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Offline Mosin

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Re: "Head Steady"
« Reply #5 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.
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Offline A10Boy

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Re: "Head Steady"
« Reply #6 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*
Regards

Andy

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1974 Kawasaki Z1a
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Re: "Head Steady"
« Reply #7 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.
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
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Online Brian

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Re: "Head Steady"
« Reply #8 on: 16.07. 2010 11:09 »
A 1953 B33, how do I know ????? Oh and a woman as well !!!!!!!!!!!!!!!!!!!!!!

Offline A10Boy

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Re: "Head Steady"
« Reply #9 on: 16.07. 2010 11:12 »
She should have that carb up on the bench really...
Regards

Andy

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Re: "Head Steady"
« Reply #10 on: 16.07. 2010 11:24 »
Sorry Brian, just saw it on MIE and had to use it.
Cheers
'51 A7 plunger, '57 A7SS now A10CR, '76 XT500, '77 AG175 '83 CB1100F, '81 CB900F project.
Australia
Muskys Plunger A7

Offline terryk

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Re: "Head Steady"
« Reply #11 on: 16.07. 2010 14:08 »
Brain you know because of the tank badges. They were only in 1953.
1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm

Offline terryk

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Re: "Head Steady"
« Reply #12 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?
1950-53 A10 rigid/plungers, 1958-61 A10 super rockets, 1947-50 A7 longstrokes, 1949 Star twin,
1951-54 A7 plungers, 1940s M21, WDM20s,
1948-50s B33s rigid/plunger/swingarm, 1948-50s b31s rigid/plunger/swingarm

Offline MG

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Re: "Head Steady"
« Reply #13 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*
1955 A7 Shooting Star
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Online Brian

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Re: "Head Steady"
« Reply #14 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.......