Honda-SOHC

Thanks Bitsa .. just looked more carefully and indeed there is a tighter coil end that I did miss  .  That also makes sense as on one of the springs it still has collet holding washer thing on the looser end.  Mind you - I have found much wrong from a previous top-end build which further reinforces the message that you cant rely on previous work actually being done right! Many thanks again.

Fantastic .. thanks Odddjob - oddly just the other day I was wondering how best to tackle it - I shall indeed follow your advice - thanks once again 

 I believe you Oddjob - honest  - perhaps the mileage is accurately low (around 23K it says on the mileometer) .. or the oil kind to that paint!

And - doh - yes ... I meant conrods A2s not A1s (typing - hopeless!).

Many thanks once again - much learned from you once again - this is - and will be for ages I expect - a terrific learning experience.

Now all I need to do is get her back together and running again .. how hard can it be ...  

Ah .. now I see .. and attached are pics of the all that I think I need (and the crank markings are indeed still visible).  So it looks to me from what you say that the main bearings are therefore  A1 B1 B1 B1 B1 and the con rods A1 A1 A1 A1 ?  Thanks for the explanation - just what I needed!

And for the crank-case -again the oven approach worked.  I tried using a hot air blower - but the case is too large and so just sinks the heat - so into the oven she went - a tad more difficult than the kickstart seal (once off I could see there was a fair amount of corrosion around it) - but a few blows with a screwdriver (making sure that the trajectory of the said 'driver wouldnt crash into the casing) and she was out.

When putting new ones back in I guess popping them into the freezer to cool them right down may help to fit them?

Thanks OddJob - my pleasure in being able to contribute something to this excellent forum.  And as you say I have indeed got new cush drive rubbers - their cost is minor compared to the primary chain! 

In final stages of cleaning up crank cases, barrels, head etc. and will start putting all back together soon(ish).  I have taken loads of pics as I pulled it apart (thanks to digital photography - would have been hopeless with film etc.!), so armed with those and a workshop manual and parts list (and this forum!) should help me get it right! Actually - I have used some Plastigauge to check the main bearings and they seemed well within tolerances - but as the plastigauge slipped a little in places - and I was rushing - I think I'll just do it again - and check the crank bearings too.  I had no feelings that the bearings were worn when the bike was running - but I think I just want to re-assure myself!

The cases are fine (surprisingly!).  I have stripped everything and cleaned everything and am blasting everything with compressed air - so hopefully no debris will be left.

Whilst posting I thought it may also help someone to see some pics of worn and new tensioner and guide - plus the (frankly lovely) DS replacement tensioner arm.  You should be able to see the horrendous gouging that has occurred (apparently it can be repaired - but I felt mine was far too worn!).