Hi, made a start on the engine today so be prepared to be peppered with queries, the head seems in fair condition apart for one piece missing where it appears a bolt should fit , see photo. I can't see what would bolt into this missing piece so do I need to get it repaired or not?. The cylinder is grotty but technically very little damage to the bore,s , the piston is stamped +020 so if I remember correctly it can be rebored up to + 060.
1 what would be the best way to clean up the head and barrel?
2 should I have new valve guides while I'm doing it.
3 any recommendations for the rebore, I live a couple of miles South of birmingham boundary.
the piece missing is for the stud for the rocker cover, it could be built up with weld or a good stud and JB weld putty used to build up. oil the thread of the stud and it should be possible to remove stud if needed.
Ive had my cases and head blasted with a very fine media, cleaned up nicely and washed out., barrel could be blasted then painted with a cylinder black, heat proof paint.
have you checked the guides? personally, as Im spending hundreds on parts Ive had the guides done to suit new valves, saves any problem later.
rebores? should be someone locally, Personally, Piston Broke in Bristol. good but slow due to his work load.
I've used both Trident Motorcycles in Dudley (Steve) or E and D Engineering Bilston (Mick) for engineering work, both are familiar with these engines and not far from you. Yes I believe it can go to +0.060. The barrel casting and liners look very robust
Thanks both,thought it may be a stud as it lines up with a hole in the rocker box which has a nut and bolt fitted at present, is this to accommodate a stabilizer of some description ? Cheers Dave.
no, the engine steady bolts to front cover bolt not the top ones. between the front U shape cut out.
Hi Mitchell,
This is just for securing the rocker cover. The lug still with dirt around it next is for the head steady. If you do not already have them, it is worth getting a workshop manual and a parts book. Both are very helpful for a rebuild and have useful illustrations.
Keep asking questions though.
Dave.
thanks again, I have a couple of manuals but you know blokes, do it then read the instructions,..... Promise to send my ways.
Hi, cylinder head ring repaired by a fabrication co I know, they allowed me to use their head blaster and although it took some time it came up like new,when it's been repaired should I great it to keep the finnish ?.Stripping the festive going well but the clutch is well rusty and looks like it'll be a complete new assembly, the plate and filter on the underside are pretty grotty, is it possible to obtain replacements as I don't think they'll clean up well, waiting for a socket to come to remove the clutch then hopefully can split the crank cases the weekend, anything I should watch out for? Cheers Dave.
:) :) :)
If you need to replace your clutch it might be worth considering fitting a belt drive dry clutch. About £585 complete. and finding and fitting a new clutch wont be a whole lot less.
Worth a thought. I've just fitted one.
Mike 8) 8) 8)
Hi,
I have never seen so much crud in the sump of and engine. Perhaps a combination of a lot of miles and few proper oil changes. The sump parts are available so consider one with a magnetic plug to make oil changes easier and to catch any ferrous sludge.
As you will have to remove the clutch anyway have a good look at it. It may clean up but if not consider Mike's suggestion for a belt drive or a complete standard clutch. Either way cheaper than buying the parts separately.
When splitting the cases make sure all the bolts and stud nuts are removed especially the one just in front of the cam. As it looks like the engine has not been apart for some time it may be worth using some penetrating oil on the studs before trying to separate the cases. Do not use excessive force or lever them apart at the joint. If having to knock them apart use a rubber mallet or a piece of wood to hit against. Strip and rebuild like a tortoise and then you can ride like a hare.
Dave.
You will probably need the right puller to get the clutch hub off the shaft. Can be very tight
Hi, if you have any info on the dry clutch Mike I,d be interested to read up on it, I watched a U tube clip the other day which had an srm replacement clutch with some modifications that looked interesting, been covering everything in wd40 on a regular basis particularly over night and using some softwood slightly tapered wedges to ease bits appart, think your right about a pully the sprocket on the end of the crankshaft seems pretty stubborn, also having a bash at rubbing down the side covers lots of scratches and some deeper groves that I think may have to stay, thanks for the tips, if/ when this is done I may have to tour the country buying beers,
Hi,
Spent a couple of hours getting the clutch plates out today, rusted in pretty badly but came up with a way of getting the beggars out, ground the top of a wood screw and by screwing into the appropriate slot the spiral wound the plates out, my manuals don't refer to the exact clutch I have but looking at what I now have I presume the sprocket on the crank and the clutch housing "just" pull off.....gave up this afternoon, suffering phil,s problem freezing cold feet........ Wonder if I could bring it into the kitchen.
Good afternoon,
I like the use of the wood screw as a plate extractor. Whilst it all looks a bit manky the slots for the plates look quite good and the plane plates may even clean up and be usable so long as they are flat. The basket and crank sprocket should just slide off with the chain unless the rollers are seized. If they are then the track they run on could be damaged and anything other than perfectly smooth is not really usable. A specific puller is need to remove the centre/sleeve from the gear box main shaft. I would do a bit more cleaning and then see what is needed to make it good clutch. You may find that buying complete new one is the best option. The advantage of buying a complete SRM clutch is that they say they match/assemble the parts for best fit and comes with the SRM pressure plate that on its own is about £60. Add on new plates, roller bearing, springs etc. and the complete clutch looks like a bargain. If you are going to keep/use the bike it will be worth it.
Currently I am running an old 4 spring in quite a pokey engine but will probably get an SRM 3 spring some time in the future.
Dave.
I'd stick with the 4 spring clutch. Superior design that BSA dropped to make the cheaper 3 spring.
Mine is light as a feather. Get a SRM pressure plate if you want to spend money.
I refitted a Bob Newby clutch to a customers bike which I was asked to strip, service and rebuild. Bob was very helpful even upgrading to the latest spec belt, no oil leaks to worry about.
the owner, and a fellow soldier built the bike in Germany years before but it never went well and hardly got used due to work. 'the dry clutch was there would I buy one?
in short no.
advantages , no leaks, providing bushing from engine is good, quiet, customisable casing, no need to adjust.
disadvantage, initial cost. I dont do the mileage to warrant the cost.
Hi Nanoevol,
I have the early 4 spring which has the captive thrust washers. I think this has the least wobble when assembled but needs specific plain plates and the basket is cast so prone to damage. Mine was in excellent condition except for a broken tooth. May not have been a problem but I manage to find genuine original basket and plain plates as the originals were not quite flat. Although it seems to be heavier than the later 4 spring and 3 spring I think I have the best clutch. As you say the SRM pressure plate would make it even better. Had I been starting from scratch the cost of the separate components would have exceeded the cost of the SRM clutch and they only offer a 3 spring for the A65. I am still getting my clutch set up properly and will decide after a few thousand miles of two up and camping gear riding to see how it goes.
Dave.
Hi Chaz,
The BNR clutch and belt drive looks amazing and gets good reviews but there is no 'cush drive'. For the advantages the extra cost over a new standard clutch may be worth it but how much is a replacement belt and how long do they last?
I have just fitted a new triplex chain to a high mileage A65. It is the second one I have fitted so the third chain on this engine. With well over 100,000 miles on two chains that works out quite cheap.
Dave.
Dave, cant remember actual price but when I spoke to Bob about the set up he said the small amount of oil on the belt wasnt a problem as the belts were kevlar and would last miles , they wont fray or crack or stretch. The only thing on our bike was that it was an original unit . the newer units are a different width belts which were easier to get hold of 25mm too 30mm or similar , he asked for our old parts and machined them to suit and supplied a new belt. I think the belt was around £35 and the machining an hours labour.
the caveat here is , inside the case they are safe, with customisers they have the option to cut away the casing to show off the clutch as Harley and Ducati owners do. I had a Harley sportster with rear belt drive, everyone said, low maintainance , clean and didnt need adjusting. I rode 100 miles the day we bought it, went to pull away from lights and the belt snapped. either due to a flint chip from the road or peeling chrome on the rear sprocket, a fluke. I spoke to another on the Harley forum in America, he rode into the dealer to get his belt changed, pulled out of the shop and his belt snapped. So, as its inside the cover it should last
Hi,
So about £35 for a belt and about £45 for a chain. I know a chain can last at least 40,000 miles if not more, so what is the recommended replacement mileage for a belt?
No cush drive and a superior design of clutch vs a cush drive and a less good design of clutch.
A dilemma?
Dave.
Hi, still having problems removing clutch housing, must be missing something as the u tube videos I've watched make it look as if it comes off easily with just a bit of wobbling, I've got a pully on mine and it won't budge, tried heating with a blow lamp, no joy, now I'm looking at it and wondering if that centre castles peice has to come of first but if that's the case how do you grab it? Is there a special tool? None of the videos nor either of my manuals show or mention such. Eagerly waiting desperately needed help, cheers Dave.🍻🍻
Years ago, when experiencing initial mid life crisis I bought a 1200 HD Sportster, mainly because it looked more like the bikes I rode in the early 60's - I believe it was the first HD model to be so equipped, the parallel 800 Sportster still employed a chain at the time. As far as was humanly possible I absolutely thrashed that 1200, upgrading as I progressed i.e. it came with a single disc - lethal.. I fitted a second disc - not much improvement, I ended up with a Billet six pot system - result definitely. As I persuaded it to go faster so it was then necessary to make it stop faster, and so on but the one thing that never gave any problems was the final drive belt! I did about 40.000 miles on that bike (fastest tractor in the world) before selling it and buying a Ducati 888 SP5. It hardly depreciated, which is strange given that it was an anachronism when it was new. The other very strange phenomena was that the HD, insured with Aviva (then Norwich Union) on a rider policy cost more to insure than the 888. The 888, in 1992. cost just over £15000 from Allan Jefferies at a time when a Fireguard cost in the region of £7000 & the HD was slightly less. The HD as standard was sub 100 MPH. the 888 was on the rev limiter at about 165 MPH, go figure!
Hi Mitchell,
The middle bit that the plain plates slid on to should pull off and as you have said may need a bit of a wobble. The main centre nut holds this on. Once this has been removed you are left with the centre or sleeve that fits on the taper on the gea box main shaft. This needs a puller that threads in to the sleeve and then when tightened pushes against the end of the shaft. The fit on the taper can be very tight.
Dave.
Hi,....... frustration Ahhhhhhh, tight your not kidding, this is what happened to the puller, going to have to put the thinking hat on.
Hi Mitchell,
Do you have a picture showing more of the clutch centre as I cannot see exactly what you have there. The puller looks like the one below and it threads in to the sleeve as shown.
Dave
Hi Mitchell,
I have had another look at your previous pictures and you have removed everything except the sleeve that goes on the main shaft taper.
What manuals have you got? The BSA workshop manual covers the clutch from about page B21.
Dave.
Hi Dave, I have another puller coming today, I'll take some more photos this afternoon but the centre of my clutch looks nothing like your pictures, cheers Dave.
Looks like he used (and broke) this kind of tool:
(https://i.imgur.com/LdSHe2vm.jpg)
Easy to do.
Get one like Dave Brady pictured.
Afternoon, your both bang on, on closer inspection of your pictures Dave and cleaning the internal diameter I discovered a thread.so next question where can I buy the correct puller( as in your photo) I haven't seen anything like it in my searches. Although I gave the whole lump a clean down before I started I decided this afternoon to give it another going over so I don't miss stuff (hopefully) in future,so a spray can of degreaser has just been liberated. Cheers Dave.😀😀
Forgot to add, these are the manuals I'm using.
Hi Mitchell,
It looks like you have a BSA manual and a Haynes one. These should be enough with the BSA one being the one to rely on more than the Haynes. If you look towards the back of the BSA one there should a few pages with illustrations and numbers for 'service tools'. The clutch sleeve puller is there. If you google it you should get the correct puller. I have just put this "BSA A65 clutch sleeve puller" in a google search and several came up. If in doubt buy one from SRM and make sure it is for your clutch.
Dave.
Hi, received the appropriate extractor yesterday from Burton bike bits, screwed it into the sleeve about 4/5 mms tightened the centre bolt and just stripped the thread of the tool, checked with Burton this morning they assured it was the right thread so tonight cut of the damaged thread drilled the centre a bit deeper and tried again same result, don't really know where to go from here, any suggestions would be appreciated as always. Cheers Dave.
:) :) :)
You might try putting your puller into place tightening up as much as possible without murdering thread, then giving the end a clout with a hammer which MAY jar it loose.
Dry clutch versus std clutch. Jury is still out from my viewpoint. Bike is messing about(gotta be my fault)so as yet unridden.
Mike 8) 8) 8) 8)
It is just possible that you were supplied with a puller for the 3 spring 1966 on clutch. This is 1 inch x 20tpi.
The 4 spring takes tool 61 1912 which is 1 inch x 24tpi (not 26 tpi as advertised by some ebay sellers) This might be marked P127 if a pattern MCA item.
Good idea Mike, maybe enough thread to try one more effort, burtons did assure me it was the right thread but I have to say it didn't feel quite right screwing in, I'm a builder / plumber so crossthreading is something I've seen a bit and you just get a feel when something isn't screwing quite right. The tool I ordered was a 61-1912 but the one sent was either a 61-3766 or 61-3166 it was 're written by hand and not very legible.hey ho tomorrows another day.
67 3766 is the 1966 on puller.
Mmm, think I need to phone them again and get them to check, thanks Julian.