17. BSA A10 Renovation Rear Guard Action

After a very long wait, the custom made stainless steel rear mudguard brackets have finally arrived and they fit perfectly. All I need to do is get them on the buffing wheel and polish them to a mirror finish and then bolt them on to the hockey sticks.

At last I can try the new stainless mudguard in place and to my surprise it does not need cutting at all as its length is perfect. However with the mudguard drilled and fitted to the new brackets there was one small problem. Whilst the mudguard is pressed thinner at the front, to pass between the legs of the rear swinging arm, the designers have failed to account for the two gussets on the swinging arm where the arms meet the cross tube. These gussets prevent the mudguard fitting snugly into the swinging arm and also hold the two "U" brackets, that bolt the mudguard to the frame at the front, too far away from the mudguard. The answer was to mark the mudguard where it touches the swinging arm gussets and allow for the up/down movement of the arm. I then took the mudguard back to my friend who cut out the two marked areas and welded fillet plates in place. One more check in the frame and it now fitted perfectly. So back onto the buffing wheel to re polish the mudguard  and then it was time to bolt the mudguard in place.


I made some small aluminium spacers to fit between the "U" brackets and the mudguard and some black flexible plastic gaskets to fit between the "U" brackets and the frame. Then on with the brackets with nice stainless bolts and dome nuts and the fit was excellent.

I had already decided that I did not want to re-fit the old BSA A10 number plate and rear light to the new rear mudguard and was looking through a vehicle wiring and accessories catalogue, when I came across
the perfect answer. A beautiful replica rear light with a shaped chrome housing and would you believe it, the firm was only 4 miles away? So I got into the car and went to have a look. The light was even better than I expected and although it was a bit expensive, I couldn't resist it. Of course that also meant that I needed a new number plate. So onto the Internet to order a pressed aluminium black and silver plate.

Fitting the rear light turned out to be a longer job than expected as, not only did I have to drill the rear mudguard, but one of the fixings had to be vertically down on a sloping surface and once drilled, I then had to make a sloping spacer to allow it to bolt securely onto the mudguard without distorting it.

Even the bolts needed to secure the rear light had to be countersunk to fit the housing and they were not supplied with it. So I set about turning some countersunk Allen key stainless steel bolts on the lathe. All very time consuming, but at this stage there was no point in bodging the job.

With the rear light in place it was time for the number plate and what a disappointment! I was expecting one like I had fitted on my scooter. A black plate with polished aluminium digits showing through. When I got it, it was painted black and then the digits had been painted silver on top of the black. This certainly was not good enough, so I decided to polish the digits on the buffing wheel to a mirror finish, which of course destroyed the black paint as well, and then mask off the polished digits and respray the plate black again. It worked and with the aid of two more spacers to stop the plate rattling against the mudguard, the plate was bolted in place.

One finishing touch left was the rear reflector below the plate and the job was done.

Next step; the dynamo.

 I would love to read your comments on this blog. If you would like to make some please click "Subscribe to: Post Comments (Atom)" at the bottom of this page. If you would like to be automatically informed when a new episode is posted then please tick the "Join this site" box at the bottom of the page. Thanks for reading. Kevin

 Copyright K. Hopcroft  13.12.12 All rights reserved
 You can contact me on: hopcroftscoot@gmail.com

My Other Blogs:

1961 Ariel Arrow Super Sport Motorcycle :
http://60sclassicmotorbikes.blogspot.co.uk/2014/01/1961-aerial-golden-arrow-restoration.html

Miniature Land Rover Defender:
http://miniaturelandrover.blogspot.co.uk/2016/02/1-miniature-land-rover-defender-idea.html?view=timeslide

1971 VW Karman Ghia Convertible Car:
http://karmannghiarestoration.blogspot.co.uk/2017/03/1-karmann-ghia-retoration-project.html

Motorcycle Trailers / Caravans:
http://motorcycletrailersandcaravans.blogspot.co.uk/2018/01/1-motorcycle-trailers-problem.html

16. BSA A10 Chain Reaction

It's now time to address the chain case and all things contained within. Having already polished the inner chain case, I offered it onto the crank case, with a new gasket and plenty of blue sealant and tightened the two internal fixing bolts, which are drilled to accept a locking wire that passes between them. The two original bolts went in OK but as I tightened the second one, it snapped! leaving the thread in the crank case. OMG! I removed the other bolt and the inner chain case again and to my horror there was no thread sticking proud of the crank case to get hold of. How to remove it? I took a long thin screwdriver and poked it through the other fixing hole to see if it was a blind hole or if it went right through into the crankcase. It went right through!. That was more bad news as it meant that, if I drilled out the broken thread, the metal swarfe could drop inside the crank case and require a full engine strip again.

I decided to measure the one remaining good bolt and work out how much thread was left inside my crank case. I then put a collar on a small drill to prevent the drill going right through the broken bolt thread, allowing me to drill a blind hole in the stud. I centre punched the middle of the broken stud and drilled, very, very carefully. There was always the chance that if the drill bit into the broken stud stuck, it could screw it straight through the crank case and deposit it inside the engine, but fortunately the broken stud was well stuck. Once the hole was done I then took a small "easy-out" (which is like a left hand thread tap) and screwed it into the hole. As it bit, to my relief, the broken stud unscrewed out of the crank case in one piece. Brilliant!!.

I was then considering re-assembly when I was going through my draws containing parts I had removed from the bike, when I came across a large round flat plate. It was obvious that this plate was the same shape as the inner chain case where it fits to the crank case. Obviously a spacer. It turns out that in order to line up the inner chain case with the frame where it fixed at the back of the bike, BSA introduced a spacer to space the inner chain case off the crank case and this was it. So I now needed to order two new fixing bolts and two new gaskets, one to fit each side of the spacer. Once they arrived the inner chain case and spacer could be mounted in place and the two new bolts tightened and secured with the locking wire. Also the adjustable plate that fits behind the clutch was fitted with new bolts and the felt seal to prevent oil leaking out of the chain case onto the gearbox. The securing bolts for this plate could not be tightened as the plate moves with the gearbox to adjust the primary chain tension, once the chain is fitted.

Time to fit the clutch and cush-drive. The outer clutch bell fits with 20 loose roller bearings which are held in place by the inner clutch bell (or basket). Having fitted the centre washer locking plate and nut, I was disturbed to notice that the only thing holding the clutch together was the thin tab washer. This did not seem right, so I sent photos to Lightning Spares and they confirmed that the washer under the nut was the wrong one and that a much larger and thicker washer was needed to hold the inner bell onto the splined shaft in the centre. I also sent pictures of the clutch plates  and was advised to change all of the friction plates as these were soaked in oil. I had assumed that the clutch ran in oil, like my Lambretta, but was was informed that the small amount of oil in the chain case only sits in the bottom to lubricate the primary chain and that the clutch runs dry.

So on with the new clutch plates, and after making a screwdriver with a slot in it (for adjusting the clutch spring tension), the outer pressure plate with it's four springs and adjusters, the clutch is now in place. The cush drive was fitted and the two sprockets aligned and the nice new chain run around the two sprockets. The cush drive was fitted with a new special SRM hexagon nut/plate and torqued to the correct setting and the gearbox could now be adjusted to tension the primary chain to the correct half inch play tension. Then the adjustable splash plate behind the clutch could be tightened in its final position. Now just a case a fitting the outer chain case cover and job done! Excellent.

 I would love to read your comments on this blog. If you would like to make some please click "Subscribe to: Post Comments (Atom)" at the bottom of this page. If you would like to be automatically informed when a new episode is posted then please tick the "Join this site" box at the bottom of the page. Thanks for reading. Kevin

 Copyright K. Hopcroft  07.12.12 All rights reserved
 You can contact me on: hopcroftscoot@gmail.com

My Other Blogs:

1961 Ariel Arrow Super Sport Motorcycle :
http://60sclassicmotorbikes.blogspot.co.uk/2014/01/1961-aerial-golden-arrow-restoration.html

Miniature Land Rover Defender:
http://miniaturelandrover.blogspot.co.uk/2016/02/1-miniature-land-rover-defender-idea.html?view=timeslide

1971 VW Karman Ghia Convertible Car:
http://karmannghiarestoration.blogspot.co.uk/2017/03/1-karmann-ghia-retoration-project.html

Motorcycle Trailers / Caravans:
http://motorcycletrailersandcaravans.blogspot.co.uk/2018/01/1-motorcycle-trailers-problem.html

15. BSA A10 Chain Gang

Now that the gearbox is in place, it's time to fit the final drive chain and the chain guard. I felt that it was not a good idea to re-fit the old chain as I have no knowledge of how old it is or what kind of life it has had, so I bought two new chains. The final drive chain and the primary drive chain, which  I will fit later.

The final drive chain came with a split link so it was simply a case of running the chain around the two sprockets and fitting the split link. Easy.

Fitting the chain guard was not so easy. Having been tempted by a lovely custom made stainless steel chain guard, on EBay, I offered it up to the frame to find that none of the mounting holes lined up. In fact two of them were missing. Not to be put off I decided after much thought that it was best to use one of the existing holes in the new guard and re-drill the frame. This involved marking the rear chain guard lug lower down than it's original top hole and re-drilling the lug in the new marked position. This gave me a pivot point in the correct position. The guard could then be set at the right angle and the two front mounting lug holes could be measured from that point. These measurements were then transferred to the guard and marked on the guard for drilling.

You would think that to drill a flat piece of metal would be straight forward, but this stainless steel turned out to be exceptionally hard. Despite the fact that I was using a pedestal drill, nothing seemed to touch it and I managed to ruin two drills before I realised that I needed another approach. I phoned my friend who has been an engineer all his life and he informed me that to drill hard stainless steel you need a very slow drill and once you start drilling, don't stop or the surface you are drilling will harden. The drills I had in my workshop were all too fast, but I remembered that I did have a variable speed drill at home that I had never used. With the variable speed drill in the pedestal and a small sharp drill in the chuck I tried. Hey Presto! through it went! I just then increased the drill size 1mm at a time until the holes were done. Isn't knowledge wonderful?



With the holes all done the chain guard fitted beautifully, but it left the bottom rear support lug dangling down from the swinging arm and not being used. It had to go. But I did not want to remove the swinging arm again and I could not get a hacksaw in. The answer was a Dremel with a cutting disc on it and after about 10 minutes the lug had gone and the raw metal repainted. It was now just a case of bolting the guard in place. I decided to put the bolts through from the right side of the bike to allow me to fit polished stainless steel dome nuts on the left side. This done it was on and looked beautiful.

If you have ever built a show bike, or car, you will know that the process is on-going and as you do one thing a new idea emerges that makes you change your earlier decisions. This happened with the chain guard dome nuts. I decided that they looked so nice, I would change all of the nuts on the bike, wherever possible for dome nuts. So I have re-ordered all of the crankcase and engine and gearbox mounting nuts and will change all of the already carefully polished stainless ordinary nuts for domes. More expense!

 I would love to read your comments on this blog. If you would like to make some please click "Subscribe to: Post Comments (Atom)" at the bottom of this page. If you would like to be automatically informed when a new episode is posted then please tick the "Join this site" box at the bottom of the page. Thanks for reading. Kevin

 Copyright K. Hopcroft  01.12.12 All rights reserved
 You can contact me on: hopcroftscoot@gmail.com

My Other Blogs:

1961 Ariel Arrow Super Sport Motorcycle :
http://60sclassicmotorbikes.blogspot.co.uk/2014/01/1961-aerial-golden-arrow-restoration.html

Miniature Land Rover Defender:
http://miniaturelandrover.blogspot.co.uk/2016/02/1-miniature-land-rover-defender-idea.html?view=timeslide

1971 VW Karman Ghia Convertible Car:
http://karmannghiarestoration.blogspot.co.uk/2017/03/1-karmann-ghia-retoration-project.html

Motorcycle Trailers / Caravans:
http://motorcycletrailersandcaravans.blogspot.co.uk/2018/01/1-motorcycle-trailers-problem.html

14. BSA A10 Top Gear

Having assemble the BSA A10 gear box, it is now time for a final polish and fitting the gearbox into the frame. Handling the gearbox for polishing when assembled is difficult because it is so heavy, which is why I stripped it in the first place. However it was well worthwhile as the reassembly process had left it looking a bit dull and it was good to polish where the three casing parts come together to give a nice nice finished look.

Fitting the gearbox required the removal of the right hand engine mounting plate. This was no problem as the left hand plate and the front mountings held the engine in place with no problems. The gearbox could then be passed through from right to left, followed by the right hand engine mounting plate and the two gearbox upper mounting plates. I passed the bottom gearbox pivot stud through the engine mounting plates and put the nuts on loosely. No point in tightening them as the gearbox has to pivot when adjusting the primary drive chain, which I'll cover later. The top adjustable gearbox fixing bolt, and adjusting mechanism was then fitted again loosely and then all of the engine and gearbox mounting studs and nuts could be tightened apart from the top two gearbox mounting plate nuts which need to be left loose to accept the Ski-slope that hooks over them and the battery tray.

You will notice from the photos that the clutch lever is not fitted at this point. Firstly because it has not arrived back from the chrome platers yet and secondly because I felt that it was best set up once the clutch was in place, which has yet to be fitted.

The gearbox is in, and looks excellent. BSA experts may notice, if you look carefully at the photo above, that something is missing from the inner timing cover, to the right of the picture. This will come back to bite me later!!

 I would love to read your comments on this blog. If you would like to make some please click "Subscribe to: Post Comments (Atom)" at the bottom of this page. If you would like to be automatically informed when a new episode is posted then please tick the "Join this site" box at the bottom of the page. Thanks for reading. Kevin

 Copyright K. Hopcroft  01.12.12 All rights reserved
 You can contact me on: hopcroftscoot@gmail.com

My Other Blogs:

1961 Ariel Arrow Super Sport Motorcycle :
http://60sclassicmotorbikes.blogspot.co.uk/2014/01/1961-aerial-golden-arrow-restoration.html

Miniature Land Rover Defender:
http://miniaturelandrover.blogspot.co.uk/2016/02/1-miniature-land-rover-defender-idea.html?view=timeslide

1971 VW Karman Ghia Convertible Car:
http://karmannghiarestoration.blogspot.co.uk/2017/03/1-karmann-ghia-retoration-project.html

Motorcycle Trailers / Caravans:
http://motorcycletrailersandcaravans.blogspot.co.uk/2018/01/1-motorcycle-trailers-problem.html