Author Topic: next bike(s)  (Read 614 times)

Offline BSAmoto

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next bike(s)
« on: 04.01. 2020 22:32 »
Happy New Year to all of you!
To fill the free time with work, I started on the A10 project bike. The engine will get some Norton internals but today I worked on the frame, fitted a BSA front fork and removed the rotten swingarm rubbers.

After the rubber and inner tube was out, I welded a washer into the outer tube. Now it was very easy and quick to push the tube out, I started with my hydraulic press and once the tube moved a bit, I knocked it out with a rod. Same on the other side and after just half an hour after start, the swingarm was ready for bronce bushes.

Then I realised that due to using rubber stuff, nobody at BSAs ever thought about proper alignment of the two inserts as the rubber is very "forgiving" should something not line up properly. I decided against line reamed bronze inserts (rear end would have been 2mm out).Reworking both recesses would be very time consuming so I decided to weld new steel tubes in the correct angle and alignment into the swingarm recesses.

So the shouldered bushes were turned down to 27,5mm outer diameter and the steel insert to 31,6mm outer diameter. Thus I could slide it into the swingarm tube, align everything and weld the inserts to the swingarm through 6 chamfered holes (each). Now the bronce bushes have a slight pressfit, are completely concentric and the 24mm hardened inner sleeve pushes through with about 2/100mm play.

I am very happy with the result. Next is a 16mm swingarm spindle, then the empty rear brake drum gets a (modified) Norton brake plate as I am unable to locate the proper part. In the meantime I am busy fixing the engine plates that came from Ebay GB - half the holes don´t line up properly with my frame.

So within the next week I should have the gearbox, swingarm and empty engine sit properly in the frame and all needed bolts are made to measure. A primary case is on its way from US - I have not yet decided if I modify both halfs for alternator fitment, maybe I glue the neccessary dimensional changes onto the cases and  use them as a mould in the local foundry.

To compensate the shrinkage the local car painter can put about 2mm of spray filler on - did the same with some Norton cases for my 905 project and it worked perfect. The Norton crank is already designed for fitting an alternator and finding the BSA police cases is searching for hens teeth ;-)

Anyhow - a Super rocket has landed here as well so after many years of Nortons and Vincents I will be trying the BSA way this year!

Offline KiwiGF

  • Last had an A10 in 1976, in 2011 it was time for my 2nd one. It was the project from HELL (but I learned a lot....)
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Re: next bike(s)
« Reply #1 on: 04.01. 2020 22:56 »
Happy New Year to all of you!
To fill the free time with work, I started on the A10 project bike. The engine will get some Norton internals but today I worked on the frame, fitted a BSA front fork and removed the rotten swingarm rubbers. After the rubber and inner tube was out, I welded a washer into the outer tube. Now it was very easy and quick to push the tube out, I started with my hydraulic press and once the tube moved a bit, I knocked it out with a rod. Same on the other side and after just half an hour after start, the swingarm was ready for bronce bushes. Then I realised that due to using rubber stuff, nobody at BSAs ever thought about proper alignment of the two inserts as the rubber is very "forgiving" should something not line up properly. I decided against line reamed bronze inserts (rear end would have been 2mm out).Reworking both recesses would be very time consuming so I decided to weld new steel tubes in the correct angle and alignment into the swingarm recesses. So the shouldered bushes were turned down to 27,5mm outer diameter and the steel insert to 31,6mm outer diameter. Thus I could slide it into the swingarm tube, align everything and weld the inserts to the swingarm through 6 chamfered holes (each). Now the bronce bushes have a slight pressfit, are completely concentric and the 24mm hardened inner sleeve pushes through with about 2/100mm play. I am very happy with the result. Next is a 16mm swingarm spindle, then the empty rear brake drum gets a (modified) Norton brake plate as I am unable to locate the proper part. In the meantime I am busy fixing the engine plates that came from Ebay GB - half the holes don´t line up properly with my frame. So within the next week I should have the gearbox, swingarm and empty engine sit properly in the frame and all needed bolts are made to measure. A primary case is on its way from US - I have not yet decided if I modify both halfs for alternator fitment, maybe I glue the neccessary dimensional changes onto the cases and  use them as a mould in the local foundry. To compensate the shrinkage the local car painter can put about 2mm of spray filler on - did the same with some Norton cases for my 905 project and it worked perfect. The Norton crank is already designed for fitting an alternator and finding the BSA police cases is searching for hens teeth ;-) Anyhow - a Super rocket has landed here as well so after may years of Nortons and Vincents I will be trying the BSA way this year!


Great stuff thanks, can you also do pics for us as you do this work?
New Zealand

1956 A10 Golden Flash  (1st finished project)
1949 B31 rigid “400cc”  (2nd finished project)
1968 B44 Victor Special (3rd finished project)
2001 GL1800 Goldwing, well, the wife likes it
2009 KTM 990 Adventure, cos it’s 100% nuts

Online Greybeard

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Re: next bike(s)
« Reply #2 on: 04.01. 2020 22:56 »
Wowee!
Greybeard (Neil)
2023 Gold Star
Supporter of THE DISTINGUISHED GENTLEMAN'S RIDE https://www.gentlemansride.com

Warwickshire UK


A Distinguished Gentleman Riding his 1955 Plunger Golden Flash

Offline a10 gf

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Re: next bike(s)
« Reply #3 on: 05.01. 2020 09:27 »
Thanks for a great story! & yes, some work pictures would be very nice to see.
(and edited it introducing some lineshifts\spaces to make it readable without getting a headache :O)


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Offline Seabee

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Re: next bike(s)
« Reply #4 on: 05.01. 2020 21:06 »
Please explain more about using Norton internals.............
1961 Super Rocket
1957 Road Rocket
2009 Harley Electra Glide Classic
1993 Harley Springer Softtail
1971 Harley Shovelhead
1970 Harley Sportster Chopper
1957 Harley Panhead Chopper
1982 Yamaha XT550
2001 KTM EXC 400
1970 Honda CT70
Southern Illinois, USA

Offline BSAmoto

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Re: next bike(s)
« Reply #5 on: 05.01. 2020 21:52 »
Please explain more about using Norton internals.............

It seems that I can make a Norton crank with 89mm go round in the cases. As I only have an A7 cylinder to play with, the bore is more or less limited to 68mm plus one or two overbores - so this is the same as the 650SS Norton.  Will be nice to make the BSA behave like my 650SS.

Offline BSAmoto

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Re: next bike(s)
« Reply #6 on: 17.01. 2020 19:45 »
Some progress is made: finished fitting the Norton drum plate to the BSA hub, made a stub axle for the drum and another axle for the wheel. Drum got an imperial bearing that I had new in the box, the hub was converted to metric bearings as the axle slots in swingarm were 17mm as well. Found a footbrake lever of unknown origin that was milled down to the required diameter of the BSA frame hole. When the primary case arrives, I cvan weld on the lever for the brakerod. The rear brake lever was made entirely as the Norton lever was too short and at the wrong angle. Next was a steering stop plate that doubles as steering damper plate. As I had Triumph stuff laying around, I just used that and milled the plate from some flat 4mm plate that I had in the shop.
Next will be the fitting of the primary case and make a pair of footrests as nothing is available. Anybody have a shift lever? I can make it of course but it will take an hour or two....