Honda-SOHC

SOHC.co.uk Forums => CB350/400 => Topic started by: DayvW on March 24, 2014, 07:36:44 PM

Title: What a worn Primary Chain looks like
Post by: DayvW on March 24, 2014, 07:36:44 PM

Some weeks ago OddJob suggested that I post a picture to show a worn vs new Primary Chain ('76 400F).  I received the new one from DS today - so attached is that pic.  As you can see the new one has no links touching when laid as a 'tank track' - the worn one has almost all touching (any touching suggests an amount of wear - clearly this is well shot!).  Furthermore - when you grab a few links of the worn one and pull it apart you can feel some play in the links - needless to say no play in the new one.  I hope someone finds this useful.

Title: Re: What a worn Primary Chain looks like
Post by: Trigger on March 24, 2014, 07:47:11 PM

That chain has had some hard use. Did it cut any of the case's? If it did check the oil pump and all the oil ways for any little bits of aluminum.

Title: Re: What a worn Primary Chain looks like
Post by: LesterPiglet on March 24, 2014, 07:49:45 PM

Thanks. I'm sure someone will benefit from this picture.

Title: Re: What a worn Primary Chain looks like
Post by: DayvW on March 24, 2014, 07:56:49 PM

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.

Title: Re: What a worn Primary Chain looks like
Post by: DayvW on March 25, 2014, 08:17:25 AM

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!

Title: Re: What a worn Primary Chain looks like
Post by: DayvW on March 26, 2014, 06:31:00 PM

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  :)