The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => Frame => Topic started by: Padsta33 on 15.07. 2016 11:37
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Finally got the A10 running after total mag rebuilt, thus having chance too take her for a blast. 1st thing apparent was the forks bottoming out badly. On inspection I noticed the chrome shroud cover on right leg has displaced thus exposing the spring. I'm unable to re seat it. Any advice.
I took off both nuts at top of fork legs and dipped the oil and there was about 1.5 inches of creme at bottom of each leg.
So second question is how do I drain them, and how much in each leg do I put in?( I take it you fill from the top nuts.)
Any help much appreciated.
Paddy.
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Fork showing loose cover.
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The chrome seal holder has sheared, will mean complete fork strip and replacement seal holders and seals. The fork leg drain in via small blanking screw on bottom of leg.
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The chrome seal holder has sheared, will mean complete fork strip and replacement seal holders and seals. The fork leg drain in via small blanking screw on bottom of leg.
Thanks For info.
How does one go about this job?
Any recommendations for where u can locate parts needed?
Do I need any special tools and how difficult a job is it?
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Hi Padster'
213cc of oil in each leg. I use heavy fork oil, I think its 30w and dampens the forks nicely. *smiley4*
ELLIS
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Its not the easiest of jobs, and some tooling is required, all is commercially available, but depends on your basic skills and facilities as they can be manufactured simply. Fork strip down topic is well documented on this forum.
The seal holders can be sourced in stainless for not much more the chromed steel, that the route I went.
The two tools required are a device for removing the seal holders, this is a hollow tube which fits over the fork stanchions and has two tangs to locate into the slots in the seal holders. The other tool is to aid assembly of the forks back into the steering yokes, this has a male thread to screw into the fork stanchions, people use an old fork top and weld some threaded rod to it. This tool can be substituted by the use of a round dowl, this is screwed into the stanchion thread. The bike needs to be lifted high at the front, tie some rope around the yokes and lift up via the yokes.
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Sounds a bit of a job.
I'm not the most mechanically minded or patient chap.
If there is any one close to Cornwall (NE Cornwall/Devon border) who would like to lend a hand I'd be very grateful. Willing to pay fuel and supply pasties/coffee etc...
Anyone.....?
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Hi folks sorry to jump in on this thread, can someone please show me the location of the drain screw/s. A photo would be appreciated. This may be nominated a thickest question of the week! I have tried to see the location but with the bike currently in storage it's difficult to see properly.
Thanks in advance Andy
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The chrome seal holder has sheared, will mean complete fork strip and replacement seal holders and seals. The fork leg drain in via small blanking screw on bottom of leg.
If one was on a budget or wanting to make the most of summer *whistle* I'd be tempted to clean the seal up, and glue it back into position, then change the fork oil, job done!
It will need proper attention some time soon though *work*
Water does get into the lower fork legs and hence oil, as water gets onto the top of the seals from the gaps in the fork shrouds higher up, and leaks down into the legs.
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Hi folks sorry to jump in on this thread, can someone please show me the location of the drain screw/s. A photo would be appreciated. This may be nominated a thickest question of the week! I have tried to see the location but with the bike currently in storage it's difficult to see properly.
Thanks in advance Andy
See arrow.
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And the next question is...... how do you seal the buggers ?? My right hand fork stantion just wont seal best results I've had were string wrapped around the screw but fibre washers just leak ,the other side is dry and no problem ,any ideas gratefully rec'd
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And the next question is...... how do you seal the buggers ?? My right hand fork stantion just wont seal best results I've had were string wrapped around the screw but fibre washers just leak ,the other side is dry and no problem ,any ideas gratefully rec'd
Thread lock or ptfe tape.
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Snap Topdad, Snap first ever advisory on the A10 and they are leaking like a sieve. Have tried new fibre washers, new rubber(nitrile stuff) washers and PTFE tap and sealant. I have now parking it next to the Notrun to see which can leave the biggest puddle *smile*
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Snap Topdad, Snap first ever advisory on the A10 and they are leaking like a sieve. Have tried new fibre washers, new rubber(nitrile stuff) washers and PTFE tap and sealant. I have now parking it next to the Notrun to see which can leave the biggest puddle *smile*
Try a small O ring.
If I get a leak with a fibre washer I just swap it for a rubber o ring. So far it's worked every time.
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And the next question is...... how do you seal the buggers ?? My right hand fork stantion just wont seal best results I've had were string wrapped around the screw but fibre washers just leak ,the other side is dry and no problem ,any ideas gratefully rec'd
Bob,
Haven't tried it myself, but how about this idea? Create a lapping tool with a pilot the size of the screw' s outside diameter and the largest shoulder that will clear any obstruction around where the head of the screw lands. Apply valve lapping compound to the shoulder and give it a spin in a drill motor to create a good seat for the fiber wssher. Of course, use new screws. I suppose you could do the reverse on the screws themselve to perfect the finish on the undersides of the heads.
Richard L.
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Aluminium crush washer or dowty seal washers both work fine.
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I like Julian's advice, but a small correction to my idea: pilot would be the minor diameter of the screw, not the OD.
Richard L.
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Folks, just moved bike and found screws! They had been painted over so hard to find, that's my excuse. Topped up forks with 213ml of oil after flushing out old oil, only had approx 20ml in each fork. Thanks again folks. Onwards and upwards.
Hi folks sorry to jump in on this thread, can someone please show me the location of the drain screw/s. A photo would be appreciated. This may be nominated a thickest question of the week! I have tried to see the location but with the bike currently in storage it's difficult to see properly.
Thanks in advance Andy
See arrow.
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The workshop factory manual and or service bulletins cover this topic quite well and well illustrated and clear instructions.
(early models use a collection of service sheets for both twins and singles, later models are covered in a factory manual. Much of the fork parts are similar or the same in a Unit type twin such as A65).
This all assumes the parts come apart easily, and near 50-70 years on they can be challenging to take apart. The fork seal holder, shroud assy on a BSA can be really challenging. Much use of expletives, heat, penetrating oils and leverage. Sometimes several days of heat and oil can be the case. The special tool for the shroud/oil seal holder is a MUST have and a good quality one is critical. You can make your own, but the small tabs have to well done and heat treated.
Torch and oil to heat treat them. It is not unheard of to destroy the shroud/oil seal holder on a old set of forks and thus replacement required. (Been there-done that) In building up project bikes or restorations I have had some terminal cases where it took several fork assys to make one good one. I have one now for my 52 BSA B33-Goldstar bitsa that I suspect is too rusty to save much. (much penetrating oil and expletives will be applied this week)
Early BSA forks tended to be not plated chrome (its a hard industrial type chrome, not to be confused with decorative chrome) and often were plain steel. some people paint them or chem treat them to prevent corrosion but at the sealing surface they have to be smooth and clean to function (no layers of paint). later style can have the surface treatment wear thru and some will still run them, others replace.
But the forks, once in the triple trees can become quite locked into place. Again, each model differs but many have a pinch bolt and I use some steel wedges into the slot to open that opening up to free the leg, but on a tapered top tree or no pinch arrangement you have to break it free. (Heat-oil-leverage) metal strap wrenches, Plumbers pipe wrenches and channel locks carefully used are the next step.
Here is some pix of the tools that you need or will need to order. 2 styles of fork draw tools (mostly installs) and the seal holder tool. I actually have several styles of these for different models (Triumph for example) This one is a spitfire brand and seems well regarded. I either bought it off FeeBay or Walridge motors in Canada. Walridge has an excellent selection of tools and I often refer people to them. Nice people too. Many other vendors carry this stuff. You COULD make these tools as well..
Oil seals: Haha! thats funny! (have you heard the penguin joke about this?) So, Oil seals and British bikes is kind of an oxymoron in many ways. later model bikes have traditional oil seals with a rubber or viton type construction tensioned with spring type material. Time change items that require replacement sooner or later. Early types such as pre 1959 Triumphs dont use a seal per se... its a piece of cloth felt material, and in some cases on some vintage machines its leather! I use to keep a sample fork oil seal holder on the work bench for a mid fiftys triumph as well as thumb tabs on some parts book to illustrate this. On the Triumph forks I suggested that you have better luck at oil retention by using a ladies sanitary napkin or Kotex tampon.
Some of my shop customers needed a great deal of education about what IS and what is NOT possible regarding their machines.. Early primarys for example.
If you dont have factory literature, it can be downloaded off the internet on multiple websites Some material is more challenging to locate than others, but most is availible for free downloads. If you like, PM me with your exact year and model and perhaps I have it already in digital format and can email the files. You can then take to any printer and make copies. I recomend placing the copies in plastic page protectors and a 3 ring binder. Shop materials tend to get soiled easily.
Last picture is my grotty forks for my Goldie bitsa, pray for me!
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meant to add the following:
A) pardon my shop clutter, I am in process of a massive remodel/re-org after many years of inactivity
B) PB Blaster IS your friend... *smile* *smile* Other people are quite fond of KROIL, or alternatively make your own blend. Several popular recipes online and opinions are very strong on which is best, regardless,,, ANY home or commercial workshop needs a LOT of this stuff for old crusty relics.
C) Some BSA forks are 2 different diameters for some reason. Thus replacements tend to be difficult as they are machined that way. Some repop stuff out there, some people retro fit more modern versions of the fork tubes or, use later model forks entirely or painstakingly retro fit early style with a variety of setups to be concealed internally. (looks original from outside)
hope that is helpful..
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Screws are a hard thing to seal no matter what they are used on.
I like something called Rectorseal 5, backed of by a fiber washer ( a dowty washer may be better still, never tried it)
Buy the smallest amount you can, it will last a lifetime.
Lee
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That looks promising, I was looking for a thread sealant like that, been a long time since I purchased anything and used up what I had from my days as a maint. millwright.
You specified this version which has impressive stats/specs. Temp and applications are impressive...
See: http://www.rectorseal.com/rectorseal-no-5/
I see though they have other variants, (White, blue etc) so have you tried their other types as well? And or The number #5 yellow seems to work the best with vintage British?
A website called Zorro has small containers for less than $6.00 so seems very affordable.
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If rectorseal 5 does not seal it, you probably need to weld it shut.
Just make sure the threads are as oil free as possible and back it all up with new fiber washer.
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Hi All,
I saw this but read something else *eek* *eek*
If rectorseal 5 does not seal it, you probably need to weld it shut.
Must take the tablets *doh*
:o
John
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Hi All,
I saw this but read something else *eek* *eek*
If rectorseal 5 does not seal it, you probably need to weld it shut.
Must take the tablets *doh*
:o
John
Rectumseal?
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*lol* *lol* *lol* *lol*
John