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Technical (Descriptive Topic Titles - Stay on Topic) => Frame => Topic started by: snowbeard on 29.05. 2009 06:15

Title: removing front fork bushings
Post by: snowbeard on 29.05. 2009 06:15
so I did my due diligence with a search, but to no avail.

I am trying to get the front fork from an 8 inch half width hub fork apart, I have the right side that the axle threads into (not the clamp side).  I have removed the allen from the bottom, and taken out the damping rod and lower piece.  I have finally gotten the leg broken free from the bushings and have about a half inch of movement up and down before either the seal holder hits or what seems like the lower bushing hits the top.

in the haynes manual it says there is a circlip there that must be prised out, but I don't see one, and can't feel any gap with my sharp pointy tool either.  when I look at the other slider I have, I don't see any groove for the clip, and I see the sloped edge down to where the bush would be, just like I see in the one I'm working on.

so what am I missing?  did the bushing get pulled up past the clip?  is it pretty obvious?  any thoughts?  heat maybe? 

I've been slowly working this thing apart for a couple of weeks now and finally had a breakthru, only to find I can't find the circlip!!
Title: Re: removing front fork bushings
Post by: A10Boy on 29.05. 2009 09:33
Thats strange, the circlip sits only about 1/4 inch down from the top of the leg - there is a slight ramp and then the groove.The circlip is only a simple wire jobbie, there are no holes for circlip pliers.

I've had them before where a shim has worked its way over the circlip, but the bush wont.
Title: Re: removing front fork bushings
Post by: RichardL on 29.05. 2009 14:00
Snowbeard,

From the Blackberry I can't provide the link (well, I could, but it's a hassle), but if you go to Bikes and Pictures and look at my file there (Richard's 55..., 2nd page, I think) you will see my approach for compressing the spring to get to the circlip. I'm not 100% sure this applies to tour problem but, to me, it sounds like it might.

Regarding Portugal, will this mean we must give up the idea of a national A7/A10 ride-in to your house in Colorado (circa Boulder)?

Richard L.
Title: Re: removing front fork bushings
Post by: beezalex on 29.05. 2009 15:10
Snowbeard,

What bike are these forks from?  You said "damper rods" so I'm guessing these are late 60's bsa forks?  If so, A65/Victor damper rod forks do not use a circlip to retain the bearing. 
Title: Re: removing front fork bushings
Post by: snowbeard on 29.05. 2009 16:47
well, in fact I don't know that it isn't a late 60's leg, it was supposedly from a 1960 super rocket, but I'm not sure the super rocket used a half width then?  the fellow also gave me a late 60's unit gas tank for it, he said he knew it wasn't correct, but he made a similar one work on his other A10 *conf*  so he may have done the same for fork legs.

so if I had the later fork leg with no circlip, what is the procedure for removing that bushing?  I was getting around to heating things maybe?


so with your comment Beezalex, am I to understand that the early A10's did not have damper rods?  and here I thought I was learning something to benefit my Spitfire!!  what would be the tell tale sign for the years?


Richard, I only have one leg to the setup, and it is off the bike, with no springs. but that looks much how I might go about it myself! very handy.  And if you guys want to start a national ride to my house in Boulder, well, I'd come back for that!!  *smile*
Title: Re: removing front fork bushings
Post by: beezalex on 29.05. 2009 20:24
Snowbeard,

No A10's originally came with damper rods.  They were not introduced on A65's and Unit singles until 1966, I believe.  Basically, the only thing holding the bushings in is the seal holder and friction.  Sometimes, that friction can be significant.  One thing you do NOT want to do is clamp the lowers in a vise.  Ask me how I know *sad2*.  The best method I've found for extracting the lowers from the legs is by putting the forks back in the triple clamps without the seal holders, re-install the axle and put a bottle jack between the lower triple tree and the axle and pressing the whole spiel apart.  This has worked well for me several times.

Hope that helps.  Good luck.
Title: Re: removing front fork bushings
Post by: snowbeard on 29.05. 2009 20:50
thanks for the info, I can only guess what you mean about not clamping the lowers  ;)

I have actually been clamping just the lug on the bottom, not the tube. maybe I can put the axle on it and pull up.   

I have access to Dry Ice and maybe a hairdryer on the slider in combo would free it up.

so just to clarify before I go beating on it, if I have a damper rod, I probably don't have circlips, right?

thanks a bunch!!
Title: Re: removing front fork bushings
Post by: bsa-bill on 29.05. 2009 22:11
If you have the damper rods that go down through the topnuts then you will still have a cirlip or should do.
These rods were after market and provide double damping.
I have a 61 flash and it definitley has circlips
the present bike I'm working on (58) had shims that had been cut, they should be a complete ring and sit between the bush and the circlip, fitting them is a case of trail and error until you get the right amount of shimming between the circlip and the top of the bush ( so there's no play)
The PO obviously took a shortcut by cutting the shim to save dismantling the stancheon and seal holder but it is possible a cut shim could move from below the circlip and mask it.
Later forks ( like A50/65 ) had some kind of shuttle damping sytem I believe, don't think it involved rods though, those with more experience of these models might like to comment.

all the best - Bill
Title: Re: removing front fork bushings
Post by: snowbeard on 29.05. 2009 22:41
jeez, it's really hard for me to tell, all I got was one fork, no topnut or springs even, with a stuck slider.  when I took the allen bolt from out the hole in the bottom of the threaded axle side (hole thru the bottom to reach the allen) I was able to take the assembly out, damper rod and suction tube(?)

I then got the seal holder loose and slid it a half inch or so up the leg to where it won't go any further.  what I see inside is a bronze looking bush about an eighth inch thick, all the way around the leg.  I see the slight bevel around the inside edge of the slider, but no clip.

I'll see what I can do about pics when I go home tonite, thanks for all the help so far!! :)
Title: Re: removing front fork bushings
Post by: Brian on 30.05. 2009 00:01
Snowbeard if you have a allen headed bolt going up into the bottom of the fork leg then you dont have the normal A10 forks. Are the springs inside the fork or on the outside ? If they are inside then you possibly have a set of 71' or 72' forks or something off a different bike altogether.
Definitely do not heat them or do anything else to force anything until you have positively identified them, most forks regardless of design will come apart easily when you know how they come apart.
Title: Re: removing front fork bushings
Post by: trevinoz on 30.05. 2009 01:52
Those forks are probably 1966 and later. The bush is only held by the seal holder. There is a conical shaped washer which bears on the top bush and holds it tight against the slider, this is a modification from the earlier type which had a circlip and needed shims to hold bush tight.
Possibly, hold bottom, not tubular section, in a vice and work the stanchion up and down against the top bush, like a slide hammer. The bush should come out.
Trev.
Title: Re: removing front fork bushings
Post by: snowbeard on 30.05. 2009 07:26
the leg

(http://img.photobucket.com/albums/v632/snowbeard/my%20bikes/fork1.jpg)

the damper

(http://img.photobucket.com/albums/v632/snowbeard/my%20bikes/dampers.jpg)

the bush

(http://img.photobucket.com/albums/v632/snowbeard/my%20bikes/fork.jpg)

the other fork leg that I hope to use, looks very similar to what I can see of the black one

(http://img.photobucket.com/albums/v632/snowbeard/my%20bikes/chromedamper.jpg)

thanks!!
Title: Re: removing front fork bushings
Post by: snowbeard on 30.05. 2009 23:44
ok, so you guys are right, I have the A65 fork setup.  I'm a little bummed that it's not original A10 stuff, but I have no one to blame but myself that I chose all the parts not really knowing any better.   

on the other hand, was the damper rod an improvement on the shuttle cock system in an A10?  maybe it's a "period upgrade to better handling"??   ;)

either way, it was the slide hammer method that got it, no circlip.  there was so much dry carbon gunk in there that the bushes weren't even meeting by about three inches. as I hammered the leg it started coming out more and more, finally the bush started coming out and finally it came out entirely. 

Looks like I need a bushings and a nut for the bottom on my other leg, but at least they match lengths!!  there was some concern that the stuck one might be "chopper" length!! 

thanks for all the help!!!
Title: Re: removing front fork bushings
Post by: beezalex on 02.06. 2009 17:44
Snowbeard, the '66-'68 BSA damper rod forks are a BIG improvement over the earlier damping system.  This is what you have.  The nice thing is, they are externally identical to A10/Goldstar forks (only a true anorak can tell from the outside) and a worthwhile upgrade.
Title: Re: removing front fork bushings
Post by: snowbeard on 02.06. 2009 17:50
thanks Alex, that is good to hear! I will be one step closer to anorak when I am done, and already now know to look for the holes in the bottom to reach the allen!  other than that I can't see anything different either! (yet)

hopefully this leg I just got free will be salvageable, it's got a good bit of rust and pitting along it, but I guess since the seals are above, as long as it's free on the bushes that shouldn't be too terrible.  time will tell.  might see if the fellow I got the first one from has another!

Title: Re: removing front fork bushings
Post by: 69Bonni on 03.06. 2009 12:45
Hi Snowbeard!
Hows it coming on?
Now i looked at your forks pictures and there going to be 66-67 onwards.
Stick with them there better than the earlier A10, i think that maybe the fork oil seal holders from A10 will fit (can anyone confirm this???) Part number 29-5310 these are the deep type, although the UK A65 had deep holders for your forks 41-5142. I cant spot much different (at the holder) other than the dished ring to retain the bush rather than the circlip

Now would you like me to send you a parts book that gives you a break down of those particular forks?

I have a PDF file right now here in front of me so if you need it give me a shout

Kind Regards

Steve
Title: Re: removing front fork bushings
Post by: snowbeard on 03.06. 2009 17:03
Hi Steve, I very much appreciate the offer, but a kind soul already took pity on me and sent a pdf spares book 00-5137 to reference.   I'm not opposed to further information if yours is different tho!

one thing I'm wondering about, the stanchions (shaft) in the book look straight all the way down, but what I have are stepped from the top, with a ring where the bottom yoke clamps, then tapered down to the slider section, then even where the slider slides.  is that correct for the 68? or are these from an earlier A10?

(http://img.photobucket.com/albums/v632/snowbeard/my%20bikes/shaft.jpg)


also wondering, the dished ring as a retainer for the bush, is that supposed to be pressed into the slider?  mine was stuck up under the fork seals and responsible for the binding...

thanks for all the help!!

Title: Re: removing front fork bushings
Post by: 69Bonni on 04.06. 2009 08:56
Hi Snowbeard!

As there normally all tapered at the top to fit the fork yokes (thats why they can be a bugger to get out!).

Sounds like they might be A65, 1964-1967 i'll tell you i have never found so many variations on a theme! there are so many variations on British bikes i will never say never! because who knows whats happened to them and whats been fitted over all those years! Another spanner in the works is the differences between UK and Export models.

Is there another oil hole drilled further up the fork leg? or just 4 round the bottom?

I think they might be these ....68-5144 ...... 22 3/4" long they were for A65 64-67 (But not 65 some 65 forks were different).

What do you think?

I'll take a look at my parts books see if its the same as what you have and let you know

All the best

Steve
Title: Re: removing front fork bushings
Post by: snowbeard on 04.06. 2009 19:35
yes, quite a few bits exist out there, was talking to the fellow who traded me the bits and we discussed how Triumph was not willing to put out lots of various models, they just picked something and stuck with it, but BSA had a million different styles all tailored to the public desires, and so it becomes ever so much harder to keep track of all the differences and such, even with the Bacon books!

so it's pretty hard to see what I was getting at in the picture I provided, so I broke it down and annotated for clarity.

A is tapered as standard for the top yoke.
B is relatively parallel, but roughly lathed
C is slightly  raised larger in diameter and parallel for the bottom yoke
D is the second taper, again roughly lathed down to the smaller slider section E, which is parallel for the rest of the run.  the lowest looking ring in E is just where the bottom bush was attached.

I only see the four holes around the very bottom of the legs, but there could be one I missed if it is plugged up, but I wire wheeled them clean to see what I really have and didn't notice one.

(http://img.photobucket.com/albums/v632/snowbeard/my%20bikes/shaft-1.jpg)

those ones you have pictured look very nice, all hard chromed and all. 
Title: Re: removing front fork bushings
Post by: 69Bonni on 04.06. 2009 22:31
Hi Snowbeard

Guess you have a name too!

I think your legs are the same as in the pictures i sent (someone has them on Ebay at the moment). But its always difficult to be 100%. but looking at the other types these look right 68-5144. You guys love your chrome dont you! ;)

The later ones had shuttle valves and your Stantion isn't a shuttle valve type and its not the earlier A10, 2 hole type.

That parts book you have shows the same fork picture as the one i was going to send you but if you need a parts book or info drop me a line.

All the best

Steve
Title: Re: removing front fork bushings
Post by: snowbeard on 05.06. 2009 00:33
ha, I guess I do have a real name, Nathan, but I've gone by snowbeard on various forums and made enough friends in my real day to day life that actually refer to me that way, I rarely think anything of it.  it all started with a telemark skiing website where I used the name because of my beard getting frozen full of ice and snow, on account of I fell a lot...  ;D

so I might be interested to find those on ebay, but i didn't see them in any of the searches I tried?  maybe I'm in the wrong country...  feel free to email me off list if you don't want to go advertising ebay auctions...

and thanks again for all the help.  I am planning to go by a local friend's house with all my parts and see what they think of all of it, plus hopefully find a half set of the bushings to complete that part of all this.
Title: Re: removing front fork bushings
Post by: RichardL on 05.06. 2009 01:01
Snowbeard,

That does solve the name mystery. It's a bit more comfortable to call you by the handle knowing its the same one outside cyberspace. Frankly, if people I know started calling me "manosound" it would feel really awkward. That was just a nom d'plume I used on an audiophile forum and I had it as an email address, as well. Had I known I would become so active in this forum I would have chosen something more fitting, like "manogas". OK, maybe that's not so good. Just "Richard" is fine, but I'll keep the member name as it is.

Oh yeah, the forks, good luck with that. You don't need my advice because what you're getting is excellent.

Richard L.
Title: Re: removing front fork bushings
Post by: 69Bonni on 05.06. 2009 15:07
Hi Nathan, Richard,

No problem with the fork stantions, im not selling them! Its a company called Heritage Motorcycles.
http://stores.shop.ebay.co.uk/HERITAGE-MOTORCYCLE-PARTS__W0QQ_armrsZ1

Item Number 140311886118.

I cant tell you the number of Nick names ive had over the years! Werzel it a common one.... some of the others are unmentionable!

Cheers Richard
Safe riding to you both

Regards
Steve