BSA A50 / A65 Engine Rebuild Tips 

Thanks for watching!

I believe 500 twin Triumphs had a T/S bush right till the last models, as did G80 Matchless/AJS singles. Sure there would have been quite a few other penny-pinching manufacturers who did that . 650 Triumphs sensibly had a T/S ball race, D/S roller, Commandos have rollers both sides [and need them]. Brit manufacturers always prioritised their spending towards bling over bearings, when the budgets were done. The fancy BSA twin tank badges probably cost more than a T/S bearing.....

@@packhams4 BSA - If you can't dazzle them with brilliance, baffle them with bull shit

I won’t do it, it’s as simple as that. This is exactly why many folks don’t work on BSA motors, too complicated and often times the customer won’t pay for it simply because the bike isn’t worth it. To each there own. You make your own choice

​ @jagitmax I tend to agree with @classicbritishspares about the tolerance. One of the biggest flaws on these cases is the lack of a second dowel pin or case alignment pin. This leaves the cam and crank as part of the alignment system. Aligning the cases by adding a dowel which requires a new bushing and line boring the crank and cam is the only real resolution. This then puts you in the place of starting with a fresh bushing. If you are worried about the tolerance of the spec you can always have the crank main journal coated with a dry film lubricant that will tighten the tolerances, burnish into place and make sure there is always oil on the bearing. I use dry film lubricants on all my rod bearings and I am stock on the stock journal sizes of most of the bikes I run. My norton has 90k miles on the stock rod journal grinds as I went to dry film lubricants at 45k miles. I have an A70 engine, I have not check to see if it had a second dowel in the cases or not, the 64 I am rebuilding for sure did not.