The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => A7 & A10 Engine => Topic started by: Jayce Lane on 23.03. 2009 11:39
-
Hi Guys
I tried to post this topic about 5 times last night and it bombed every time. I have posted a similar post with the C model forum. so here goes....
I bought a BSA over the phone a week ago after the guy sent me a couple of photos over his cellphone. However, after haggling on price and taking a closer look at it, I realised that it was not fitted with a standard bsa engine and exhaust. Because the previous owner said it was a 250 I thought I might have gotten a C11. however the guys on the C model forum are not entirely convinced that it is a C model as it has a cradle frame ie. two downpipes from the headstock to the engine. Some suggested an A7, but if I look at the plunger frame particularly at the rear wheel, it does not look bulky enough for a a7 after looking at frame drawings on the internet. Any opinions on this would be appreciated. I also realise I have a long road ahead of me, but the journey starts out with trying to figure out what I have got....
Regards
Jayce
-
The frame etc is all C11G but the engine is a odd one. A two stroke of some kind.
-
I am sorely sticking my neck out in an area I only know because I thought this was an interesting question and went looking for an an answer. Therefore, I am hesitant to disagree with Brian, but this does not appear to match pictures I found of C11s, such as the one attached. The gearbox is clearly different and there is just one downtube. I do agree that it certainly appears to be a two-cycle engine of some variety, but I couldn't nail down which one, without making it a career. I think this bike must be built on a A7 frame, but you could tell that in an instant with the number off the headstock.
Richard L.
-
The gearbox is the four speed one as fitted to the C11G's. Its possible the front half of the frame is from a A7 but I think more likely someone has been to work with a welder. When you get it you will be able to have a proper look.
-
Thanks Brian
That is the most definite answer that I have received from any one. The twin downpipre from the headstock has thrown most of the guys I believe. However I have myself have not found to much information out about the cradle frame for a C11g and frame drawings dont display the twin down pipe. Any idea on year vintage...
Whilst responding I saw your answer Richard and welcome to my world.... Will hopefully get the bike this Friday and check on the headstock for the number. My father inlaw has got it from the seller and has it at his place. He could not find the number on the headstock, but his eyesight is not what it was and the bike has been covered in a primer.
Just saw your response Brian and hope to hell the welding job is not a reality.
Regards
Jayce
-
In support of Brian's point, I suppose it's most unlikely that the C11 primary cover would have been sought out to use in an A7 hybridization. Brian probabaly knows several other reasons the C11 description fits. If it turns out to be a welded-on second downtube, that is some inspired analysis he's given.
Richard L
-
Here is a picture of what it should look like.
-
Yes, I see the gearbox issue cleared up, for me. (I was looking at the relative locations of the filler/adjuster ovals.) That's a nice looking bike. Yours?
Richard L.
-
No its just a picture I found. I have had a lot of C11 and C10's over the years but then I came to my senses and got rid of them !!!!!
-
Just a thought but I think the A7/10 plunger frame is in two halfs front and back could this be an A7 front with the C11 rear end bolted up not welded?
Richard
-
Hi Jayce. If I could add my thoughts on this one.
From what I can gather all C10, C11, C11G and C12 models had a single downtube frame. The frame you show has two downtubes but it appears to be a lightweight frame. I'm sure the A7 frame is of much heavier construction.
It would help if you could find a frame number and post it for us to determine exactly what it is.
Beezageezauk.
-
hi mate what you have there in my view is a bitsa a bit ove this a bit ove that myself i would keep clear ove it it looks like a lot ove hard work why not get an original c11 and do it up that way you will end up with a proper bike
-
Hi Rocket Man
Would love to stop the sale, unfortunately have already bought the bike. What happened was that I had only received the pictures of the left hand side of the bike, when I negotiated the sale and it is very unclear from those that there are twin downtubes. The picture of the right hand side I only got after the purchase. So I am in for it and have to make the best of it. Will pick up the bike this Friday and will attempt to find the frame number.
Richard if you are right, then I might have two halfs of a bike, I suppose I can chose which way to go either a7 or c11. Novel concept. Its like having a combination New VW beetle at the front and old VW at the back.
Regards
Jayce
-
I would suspect the only BSA part is the tank, which looks too big for the rest of the machine. I hope it was cheap ;)
-
Fido
Interesting observation the thought has passed my mind. An Ariel 200cc from the same era has a very similar back end. Cheap is relative but I picked up for 200 pounds rougly converted.
Regards
Jayce
-
Well, I think it is established, via Brian, that it is a great deal of C11, if not a great deal. Maybe, once you get it, you'll find the engine to be some rare thing that might bring a fair return. From the bit of browsing I've done, maybe it's a bastardized Villiers older than the frame and with a.bunch of broken fins. It's really hard to explain those fins if they are not broken (but, as in so many things, I'm no expert in Villiers)
.
If the engine is not valuable, and the bike can't transmorgrify to an A7, maybe it will start with minor work and you have a rat rod.to play around on. I'm finding it hard to imagine spending the time and money to restore it to a really nice C11, but others may know better and say it's a good idea.
Sorry, if I've over-chatted on this with ideas you've long-since had yourself.
Richard L.
-
200 pounds is not a lot , i think it will cast you a lot more in the long run to put right you could always dismantle it and sell the parts as spares that way you could get your money back and maybe a bit more good luck with it eanyway i dont think you could pick up a good bike for that,i suppose we all have to start someware.
-
Looks to me like a C11G with the front downtubes modified to accommodate the central exhaust port on the 2-smoke motor. Looks like the entire chassis is C11G save the frame modifications as well as the gearbox. The motor looks like an early villiers unit with some bizzarr-o top end on it.
-
I find it quite distressing that someone could even think about putting a Villiers motor in a BSA. I think we should find who did this and lynch them ! I have a particular hatred for Villiers products that goes back to when I was 12 years old and to this day ( 40 years later ) I refuse to have anything made by Villiers in my shed !!!!
-
Brian. When you're ready to share we'll all be here for you.
It's a "special" made from the finest components available.
We shouldn't be so dismissive, remember there was a time when these things were completely worthless *smile*
I like the cylinder fins, they remind me of a stack of pancakes in a Richard Scarry book.
Cheers,
Iain
-
Brian,
I own a cotton vulcan sports with a villiers 9e engine. It is my favourite motorcycle. (This may change when the star twin is finished). I have a greater afinity with this little bike than the A65 or the string of matchless' or even the velo venom I used to own. It is literally bursting with character and charm. Having said all that it has an alpha bottom end, a greeves head and barrel, a yamaha it175 alternator (rewound for 12v) cd ignition and a mikuni carburettor. at least the cases and covers are original. I must remember not to park it anywhere near you or your fisher friends.
wrt Jayce's bike, I'm not sure the motor is villiers. The only villiers after market kit with full horizontal fins, that I'm aware of, was an ajax and like most villiers engines had an angled exhaust which missed a single down tube frame. If its a villiers it will be unique unless its out of an outboard. mz also made one but it didn't look like this.
cheers
ps: maybe you are right - the engine is out of the cotton at present?
-
Its got to be worth it as a conversation piesce.
Look how much mileage we've got out of it.
Cheers,
Iain
-
Well gentlemen
Most of the recent comments have been entertaining... some have been disheartening. Seeing that this was going to be my first restore, there would have been two reasons for me doing it:
1. Just for the enjoyment of taking something totally delapidated and turning it into something new
2. Restore it so I could resell it for a profit
Luckily for the sake of my sanity going forward, I am doing it for the first reason. Furthermore, I feel classics should be ridden and seen so this was never going to be a concourse restore. To be honest, seeing that it would be my first restore, I would be completely sentimental and will most probably not sell it at all once done. If the downtube is the only thing to worry about, then I am sure that today's welding techniques are somewhat further advanced than what they were 60 years ago and the quality of materials better. So if it is mainly a C11G and this is confirmed by the frame numbers and no other evidence to the contrary arises, removing two downtubes should not be such a chore and I can find the rest of the missing bits.
As in a good murder mystery all will be revealed in good time and the plot will only thicken once I get my first look at it tomorrow night.
I have no misconceptions on how long this will take and I am not in a rush, so I will bide my time and snatch up the bargain bits when they come along.
So maybe I will end up with a C11G, maybe an A7 has a I have a swingarm frame with out the swingarm back home, or maybe some bizarre BSA combo cafe racer (courtesy Richard L)... At the end of the day it will look good, I will ride it and I know the pure joy that I will experience when I take it for its first trundle down the road.
So gents thank you for your assistance to date, the activity of the forum and number of responses I always enjoy. *smile*
Regards JAYCE
-
its like a frankenstine film without the blood where do you start in your case at the end bit by bit it will be put to life again a rolling mystery ove engineering what will you call it when its finished a bsabittsa only joking good luck with it and may it bring a lot ove enjoyment to you
-
Well...good on ya for doing this for the right reasons. I pity the fool who tries to make money restoring C11's... *smile*
-
Dear All
It is a official. I can now claim to be the proud owner of a 1955 C11g, with some modifications. The frame number is a BC11S - 4965. I can see where the centre downtube was cut off, two tubes welded along side, brought down to the bottom and welded onto the side of the engine mountings at the bottom.
Nothing that a little angle grinding can sort out. First step is to weld a new centre down tube in place. The engine, actually appears to be a home made job, castings and all and doubt worth anything.
Anyway looking forward to spending hours in the garage. Got a thrill just sitting on the machine. :) l Hopefully the enthusiasm will be maintained over the next 18 to 24 months. Thank you once again for all your assistance. Will continue posting on the C model forums, until I own a BSA A7 or A10 one day.
Regards
Jayce
-
go for it mate enjoy getting your hands dirty