Timing side bush

[Daveh67]

Hi everyone.
Looking at my timing side bush its a bit diferent.
Looks to have a steel sleve outer with a bush inside.
Has anyone seen this type.
Cheers n beers
Dave

[Daveh67]

Other side

[Bsareg]

Had one where the pegs holding the two together sheared allowing the inner to turn, cutting off the oil to crank. I only fit solid ones now.

[Swarfcut]

Its the most common type fitted, usually found on original bikes or ones restored in the 1970's. As BsaReg says, the construction allows the inner bearing material  to rotate, cutting off the oil if the retaining peg is absent or shears off. The very early engines had  what looked like a white metal bearing in a steel carrier, in effect a one piece bush, then replaced by this type.

 To remedy this, BSA moved over to a solid one piece bronze bush on later engines, and this is the best choice these days for replacement. They are available in stock sizes, and some enterprising folks will make you a custom bush enabling a well worn crank to be ground just enough to clean up, even if worn beyond a stock size, and also give a second life to damaged crankcases by boring the bush location, to allow an oversize O.D. bush.  In fact it is better to extend the life of the crank by grinding off the minimum, installing an undersize bush and getting it line bored to the running clearance on the crank journal, rather than sticking with stock recommended sizes.

 Even if just polishing the journal and installing a new matching stock sized bush, they sometimes need to be line bored....the bush closes down slightly when fitted. Plenty about this already on the Forum.

 As this is the new toy, do a bit of research about crankshaft sludge traps, and make sure it gets a good clear out!!!!!!

Swarfy.

[trevinoz]

Swarfy, are you sure that BSA moved to a one piece bush?
I have seen many engines pulled down and have yet to see an original one piece bush.

[Swarfcut]

Yes Trev.... One piece bush found on A50/65. Seager Engineering, Ipswich, Suffolk UK are currently offering 68-0334 (A65 bush 10 thou u/s) as a direct replacement for the earlier composite A10 bush. Current eBay UK listing. They will make you any size you like and offer full machining services.
 Not much help to you halfway round the world, but of interest to UK forum members.

Swarfy.

[bikerbob]

I have a 1956 A7 and a 1963 A65 and both were fitted from new with steel outer bush. The A7 when I bought it  had previously been fitted with a new sleeved bush which was not pinned the bush turned and  cut off the oil supply causing some damage the previous owner had this corrected and a new bush fitted which was also sleeved but pinned, this bush only lasted about 2000 miles when I had to strip down myself and I fitted a new solid bush and line reamed it and it is now running ok. The A65 has a pinned sleeved bush in and has been running ok for about 6 years now. If I was to have to fit a new tiiming side bush in any bike now I would go for the solid version.

[Daveh67]

cheers for the info. in the process of measuring and will probably go for the one piece unit. i know i can stake the sleeve bush and hold it well but one piece wont have any chance of failure.
the sludge trap is out and crank soaking in de greaser. ive got my new spokes so i will play wheels while a new bush gets fitted and the crank gets a good soaking.

forks are next on the list...... no damage but bushings worn and the fork tubes seem good.

[JulianS]

BSA replaced the original one piece bush in 1957 with the steel shelled version. The insert was a steel strip lined with Vandervell VP23 material rolled and inserted into the shell and located with a peg. These new bushes were pre sized, much the same as big end shells,  and fitted without line reaming/boring. The bearing material was a thin deposit.

They were described as a heavy duty bearing in the 1958 catalogues.

Same design bushes fitted to the A65 engines. Easier to assemble in the factory.

Some of the pattern bushes, both solid and composite supplied during the 1970s were quite poor quality, sometimes the oil holes in the bushes did not line up with the oil channel in the main bearing journal causing serious lubrication problems. Cannot comment on later repro bushes having been using the SRM conversion for the past 35 years.

Bulletin from December 1957 and catologue page from 1958 season.

[bikerbob]

Just a quick reminder If you have the engine crankcases split now would be a good time to remove the spring and ball which is located behind that small screw next to the timing side bush this can only be done when the crankcases are split. It would be a good idea to replace them with new parts as they do help to control wet sumping but make sure you get the correct parts as when I did mine I was given the wrong spring at first. When you fit the ball give it a little tap to seat it before fitting the spring and screw.

[coater87]

 Thank you Julian.

 I love how in the new features it has the "roll on center stand for minimum effort".

 Yesterday I pulled a muscle in my back at minimum effort.

 I am going to build a longer shallow ramp for in the shed, and just use the side stand elsewhere.

 Lee

 fixed it

[RichardL]

Lee,

I know you meant "center" stand, and I noticed the same thing.

Along with the other stuff, it was interesting that this list identifies '58 as the year of introduction for the "contoured" oil tank and tool box. Finally, did anyone know that, as of '58 (or ever), the fin edges were polished on alloy heads?

Richard L.

[RichardL]

I'm just going to say this out loud (so to speak) and give everyone a chance to chuckle under their collective breaths.

Now that I've initiated using the very local DIY makerspace machine shop, I am planning on boring my own timing side bush. Here's a link to see some of the machines. https://www.make-it-here.com/machining. I've watched the best Youtube videos on the subject and suppose I can do it with a trial run and fear only of destroying a perfectly good bushing.

Richard L.

[bsa-bill]

nothing ventured nothing gained Richard

[morris]

Go for it Richard. Just remember “measure twice, cut once”
Wish I had a workshop like that nearby...