HELP!
I RECENTLY BOUGHT A C12 1957 (OR SO IT SAYS ON THE LOG BOOK) but I'm now thinking I've bough a mixture of various models.
The front left side fork sometime siezes, so I bought some used forks off ebay, supposedly for a c12.
However after reconditioning and fitting , I find that the wheel mounting is different with a seemingly straight through rod: 0.8inch dia at both forks
My "original" forks which were on the original the bike when bought have a 0.57inch lh thread at the lhs. And are 0.8inch dia. at the lhs with a hole through this end for screwing the mounting rod into the lhs fork.
I have several questions ------
1) Are these forks as purchased the correct forks for this "1957" c12?
2) If I need to purchase replacement slider tubes, which should I ask /search for?
3) Is there anyone out there who is near E Lancs who can advise?
4) Where's the best place to buy or repair?
Any hel would be much appreciated.
There is a forum specifically for these bikes. Just type in C10 C11 C12 forum. Knowledgeable and very helpful people on there.
The front wheel setup should be like this, with screw in spindle with left hand thread.
Well at least I have the correct forks which I have stripped down and found a bit of a dinge at the bottom of the RH slider.
Now the search is on for a replacement, but can I heck find anything.
Are C12 parts difficult to get hold of, cos Ive tried most of the more popular suppliers. but these sliders are rarer that rocking horse s--t.
has anyone got any ideas?
How long is the slider. I wonder if they are the same as a B series. Also measure how far the fork brace bracket is from the top of the slider. I have a feeling that the only difference is the bracket position.
At first glance, the B series is much like the C 12 slider. However, the spindle for the B series seems to be with a clamp at the base of both Lh and Rh sliders, whereas the C12 slider which I have here is an 8/10" clamped hole on the rh base and the L handed thread on the left slider base.
I'll get those measurements for you in the morning.
I've found one slider in Australia on ebay, it's a bit steep and so is the carriage.
One other idea I've had. (and this will make you frown); I've thought about turning the bottom brass bush down by a few thou for the bottom 1/2" so that it doesn't catch the dinge and sieze. Desperate measures needed though.
Another alternative is to remove the welded on clamping assembly from a B series, and replace it with the one which is on the damaged C12 slider.
Honing the inside dinge at the bottom of the slder is difficult owing to the reach and also the centralising peg.
I bought a pair of forks with sliders on ebay, thinking they were correct, only to find that after sand blasting and painting etc. the wheel wouldn't fit, because unknowingly, I had bought forks which were for a C11. Hence my original confusion. You can Imaging my language, but I'm glad to say my wife is now speaking to me again after dodging the flying spanners !!!!!!!!
Hi,
Is it possible to put a steel tube in to the slider that will just fit past the ding and over the locating pin? Some light hammer work could then used to repair or deduce the ding. Nothing to loose in trying if you cannot use it as it is.
Dave.
It's an idea, I could turn some steel down to exact dia of the tubing, possibly give it some heat to harden it.
From what I can see looking down the tube, the ding internally is minimal, possibly abot 15 thou, so it might work.
As ive explained, it's kill or cure.
The B31 has a split bush in the right hand leg which when removed enables the eight inch brake to be fitted like on the B33. The left hand leg, the left hand thread is the same. I think both C12 and B31 use the same length legs the difference being the distance the bracing lug is from the top. That is why I asked if you could do the measurements to see if I had one.
Thanks for your responce.
The slider I have here is 11.5" long ( absolute bottom to end of thread with a thick welded lug on the inside of the tubing. This lug is 1.5" wide/long, it has 2 x 5/16" holes and is 7.5" from the bottom of the slider. (not shown on Dragonfly p/li.
This prob is driving me nuts, and she is complaining about motorbike parts on the kitchen benches.st)
The stanchion is 22" from end to end, and the oils seal holder is 47/8" long.
The dinge is about 3/8" sgare, and 3/4" from the bottom of the tube where it is welded to the spindle lug.
There are 2 x mudguard tags on this spindle lug
I have played this game with dings on the slider. Bear with me on this and I will check in the garage tomorrow and measure the ones that I have. I will get back to you then.
I've prepaired and polished a 38mm hole saw so that its a good tight but slideable fit down the slider. All I have to do now is to devise a method of accuratey getting it down. I think I might weld a 14mm steel bar onto it with a 12mm hole for the spindle peg.
However, I'll wait in hope for any news you might have. Fingers are crossed.
When you say right hand are you standing facing the bike and is it the one with the bush and clamping screw. If it is this then I have the one, it fits all your measurements. I fitted it to my B33 and then found that the bracing lug was higher. The clamping screw thread is weak and the clamp is a bit chewed up, not by me, so will need a nut on the bolt. All works ok comes with the bush. Yours if you want it. Just pay postage.
Oh dear!
It's the wrong one! the one I need is the threaded side. It hasn't been my week. I'm sorry I've put you to so much trouble, my fault and I'm a bit embarrsed.
So, it's back to route 1, I'll try to bore the thng out.
I can't thank you enough for your help.
No problem, good luck in trying to get rid of the ding. I have never been successful. If you are not a rivet counter you could use a pair of sliders from a B31 or B33 and fit a longer brace and stays. The sliders are the same length. The B31 stanchions are 1/2 inch longer.
Good morning,
You say "bore the thing out". Will this not leave it very thin or even break through? Also, if using a hole saw to 'bore it out' you may well cut in to the other side as the saw will tend to get pushed away from the ding to centralise thus cutting in to the other side. If you can get a metal bar or a socket on a some threaded bar, that will just slide past the ding you can then, with careful use of a hammer, dress it out. A bit like a panel beater using a dolly.
Dave.
Yes Dave, its a possibility, but the dinge isn't too noticeable on the inside, and I thought that if I took it easy, then I might take a bit of the dinge at a time. Before I do that, though, I'ce ordered some 38mm steel tubing and will turn it down so as it's a tight fit in the tube, and "thump" it down. I might try to harden the tube a bit if I can get enough heat into it.
As I've said, "It's kill or cure."
In the meantime, I've sti;; got a C11 fork set, and if I can find someone who can put a lh threading on the right slider, then that will do, I'm also looking at some B33 forks.
In the meantime, during this good biking weather, I just have to look and admire my British beauty and ride my reliable Jap. job.
Incidentally, I'm told that even in 1957, parts for c12's were difficult, no wonder they are now like rocking horse s--t to find.
Everyone's advice is been noted with hearty thanks, and I'm grateful, If all these measures work, then I'm going to set up a new business ---- Sliders repairs Ltd.
Campbell B.
The 1955 season C11G forks, which take the 7 inch front brake, have exactly the same fork bottoms as the C12 - offside part 29 5167 and nearside 29 5166.
The earlier C11 and C11G forks which take the 5 1/2 inch front brake have different bottoms and will not take the 7 inch brake, I suspect these are the C11 forks which you have.
Thanks Julian, it looks like I might have some refurbishe C11 forks to sell on, though I'll ceck them out. The top yoke is the older type which might be a give away :(.
I.m getting my lump hammer ready, and the wife's keeping well away when I come out of the garage, but at least I'm getting used to this forum , ebay, and dragon flies!!!!. https://www.bsaownersclub.co.uk/bsaoc_forum/Smileys/default/angry.gif
Thanks everyone fdor your help. I'm now back on tghe road after my fork problems.
What I did was to turn a 6mm thick walled tube down to the i/s dia of the slider to the and THUMPED IT!, for as I said, it was to be kill or cure, but it "didn't die".
The dinge came out a bit, but not so as to allow the stanchion to slide freely past it.
I found that a vacuum cleaner was fractionally smaller so I stuck a strip of emery cloth to it with superglue marking where it was at the top of the pipe and rubbed it up and down where the dinge was, being careful not to move the emery away from the dinge. after a sweaty half hour and a few changes of emery I did it.
Does any one want a 1.5 inch , 6mm waled tube to try??
Again, I'd like to thank you all for your suggestions, if anyone else has this problem, please contact me, I'll do what I can to help.