Author Topic: a7 star twin questions  (Read 835 times)

Offline edboy

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a7 star twin questions
« on: 14.03. 2015 20:15 »
hello enthusiasts.
i bought a plunger project recently and i m no expert on plungers.
so should the 55 a7 star twin have an alloy twin carb head with the bolted manifold? or twin carbs?
were the engine and frame numbers matching in this era? 1954-5.
what colour options were available at  this time?
i ve seen the green version but this frame was last painted gold. any answers appreciated.
the bike was registered in liverpool who still have the old logbook records so i could possibly obtain a copy and keep the registration number via the vmcc. anyone else tried this?
eddie

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Re: a7 star twin questions
« Reply #1 on: 14.03. 2015 21:47 »
G'day Eddie.
I might be wrong (probably) but I thought the star twin was superseded by the swing arm shooting star in '54 and was the only year with the "twin carb" head. It will fit without air filters, had one on my '51 A7 plunger for a while.
Engine and frame numbers did not match, it would be a 100,000 to 1 chance of that happening from the factory. More likely the numbers have been changed or an un-numbered set of cases were purchased and stamped as per frame. If the frame was originally gold it would have had an A10 motor.
?????
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Offline edboy

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Re: a7 star twin questions
« Reply #2 on: 16.03. 2015 19:22 »
thanks for reply muskrat. its come with a 650 engine but the frame number has an s which denotes it was originally a star twin. i ve seen pictures of racing star twins from that period with twin carbs but info is sketchy to say the least. i will try to obtain a copy of the original logbook which might have the colour entered because i agree gold does not sound correct.

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Re: a7 star twin questions
« Reply #3 on: 16.03. 2015 19:51 »
The S in the frame # just denotes a plunger frame. A star twin engine # would be AA7S-****.
Cheers
'51 A7 plunger, '57 A7SS racer now a A10CR, '78 XT500, '83 CB1100F, 88 HD FXST, 2000 CBR929RR ex Honda Australia Superbike .
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Offline duTch

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Re: a7 star twin questions
« Reply #4 on: 16.03. 2015 20:33 »

 .Not pickin' yer work Musky, but just to clarify the 'S' is for 'Sprung' frame- can imagine Ed scratchin his head .?...S is for plunger *dunno*   *smile*

 Ed, I think Star Twins originally have different tanks and obviously badges too, of which you may already be aware....?
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
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Offline bikerbob

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Re: a7 star twin questions
« Reply #5 on: 17.03. 2015 16:45 »
I have done it through the BSA owners club to retain an original registration the engine and frame numbers have to be as on the original log book if not then you can only get an age related plate. I would suggest as a first step you should find out if the engine and frame numbers match you can do this through either the BSA owners club or VMCC. You will have to send pencil rubbings of the numbers along with any other info that you have and the appropriate fee. There is the information that you need on the BSA owners website.
56 A7 s/a
63 A65

Offline edboy

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Re: a7 star twin questions
« Reply #6 on: 17.03. 2015 17:13 »
thanks for all the information. i misread the designations for a star twin as the s is marked on the engine not the frame so i probably have a a10 goldflash 1953 frame and reg with a different numbered 1953 engine. bikerbob i have never been lucky enougth to own any bsa a10 with the original engine cases but obviously the frame numbers are all  original. the vmcc seem to be more pragmatic on their website and i ll stick with them . afterall the reg is historical not valuable and would the bsa .o c. and dvla rather see the number sold and issued on a  company car for a monkey[£500]. probably!  i cant believe the engine number could be as important as the frame number as long as its a plunger a10. but more frustration ahead no doubt.

Offline bikerbob

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Re: a7 star twin questions
« Reply #7 on: 17.03. 2015 18:53 »
I think you misunderstand it is the DVLA that makes the rules not the BSA owners club or the VMCC, Who ever you use you will have to get a dating certificate. I will give you a brief outline as to how you go about it. First of all the bike has to be roadworthy even though it is pre 1960 it will in the first instance have to have an MOT which you can get on it's frame number. You will have to get a dating certificate which will confirm or not if the engine and frame numbers  were together when the bike left the factory if not then I am afraid you will only get an age related registration.  When I did it I used the BSA owners club the certificate they sent me confirmed that the engine and frame were correct  and they also told me when it left the factory which dealer it was dispatched to  the date of first registration and also what colour it was.The club also sends that info to the DVLA. You then have to fill in the correct form and send everything off to the DVLA including photographs of both sides of the bike MOT and dating certificate. Things have changed now since they closed all the local DVLA offices mine was a great help they checked all my paperwork before I sent it off they also inspected the bike checking that the engine and frame numbers were genuine. I don't know what checks they insist on now you may have to pay for someone to come out and confirm everything or take the bike to someone. I also had to pay the DVLA £55 pounds for the registration it could be more now I did mine in 2011.
56 A7 s/a
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Online morris

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Re: a7 star twin questions
« Reply #8 on: 17.03. 2015 20:54 »
When I did it I used the BSA owners club the certificate they sent me confirmed that the engine and frame were correct  and they also told me when it left the factory which dealer it was dispatched to  the date of first registration and also what colour it was.
The person I bought my SA from proudly handed me a BSAOC dating certificate at the sale. It states that; "frame number xxx, engine number xxx, BSA A10 Golden Flash, despatched to xxxx is fitted with an engine of the same period"...
At the time this looked like a nice bonus but I didn't pay much attention to it as I was just looking for a nice old bike to drive around with.
It was only after a couple of weeks I realised that this sentence just meant that it was a BSA A10 engine in a BSA A10 frame and nothing more.
As I said, to me this is not of much importance, but to someone who wants his bike to be as original as the day it left the factory, and in the process of buying from a seller who is waving a dating certificate obtained through the BSAOC then read it carefully before buying.
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Offline duTch

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Re: a7 star twin questions
« Reply #9 on: 17.03. 2015 21:45 »

 Hey Ed, in case you don't already know, I don't think anyone has said that until the very later A10's, ALL A10/7 frames have the *A7 ***** prefix whether they are A7 or A10, and it's very unlikely the engine and frame numbers will be the same as each other.

 'Matching numbers' means that they match the numbers the bike was first assembled and sold with
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline edboy

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Re: a7 star twin questions
« Reply #10 on: 17.03. 2015 22:21 »
hello, last mention of this as its offtopic but age registration plates are a fine 2nd choice by me. however if you know the registration you can obtain a photocopy of the original logbook from the relevant vehicle licencing authority if they have a record. you can then apply to keep the original registration. quite reasonable in my opinion as it belongs with the frame and its history anyway. its all explained on the vmcc website. why did the the bsoc never offer you that option bikerbob if they had proof of registration? perhaps its not as easy with dvla as it sounds? i will have to start my own ball rolling and let you all know if its possible.
 

Offline bikerbob

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Re: a7 star twin questions
« Reply #11 on: 18.03. 2015 19:14 »
When I went through the process I already had the original RF60 log book plus an old MOT but the bike was dismantled and had not been on the road since about 1974.  The DVLA had no record of the registration as when everything was taken over by Swansea in the early 80's any body who had a vehicle at that time and did not apply for the new V5 documents then the DVLA had no record of the vehicle. Which is why if you want to retain a registration you have to prove that the registration belongs to that vehicle. The VMCC and the BSA owners club systems are much the same. Also  a  number of local authorities destroyed their records and those that still have them can provide you with a copy of the original registration record but it is not a photocopy of the log book it is just a copy of the registration details. What the BSA owners club and the VMCC have is the despatch records of bikes which have all the relevant information that will satisfy the DVLA. I have also obtained age related registrations for 2 bikes which I found much easier to obtain than original registrations one of which had the  original registration number plate but I was unable to prove that it belonged to that particular bike there was no paper record.
56 A7 s/a
63 A65