500K0 Shift/clutch upgrade

[AshimotoK0]

Reading through Service Bulletin #4 (originally provided by BryanJ .. big thanks mate)... I spotted this in the pic. attached. Surely Honda wouldn't penny-pitch and tell you to re-use an 'O' ring. https://www.dropbox.com/sh/z8s0vpxu8niqva3/AAC1D8GaKGw_tvX0y2-CTcHaa?dl=0

It's interesting that the kit also contained a new --323-- clutch push rod......you know the ---323---one ..  it breaks into two pieces. Previously, as fitted on my own 500K0,  they used a CB450K1 onward ---292--- push-rod ('conventional' one piece steel part). I wonder what was wrong with the old style ---292--- push-rod and why that was changed and provided with the upgrade kit?

The original shift mechanism was obviously a carry-over design from the CB250/350K range as it's almost identical in design and uses parts common to the ---286-- engine.

Some background scary story here from the US about the gearbox/shift problem:-

http://forums.sohc4.net/index.php/topic,14675.msg1838670.html#msg1838670

This is the Kit for anyone who has never seen one: https://www.ebay.com/p/1522941856 

[ Guests cannot view attachments ]

[ Guests cannot view attachments ]

[Trigger]

The rod was in the kit as it was a supersede part by then.
On my old K0 I used the spring and ball bearing and the chap that bought the bike 5 years ago is still adding loads of miles and it is still going strong as, he keeps in contact 

[AshimotoK0]

The rod was in the kit as it was a supersede part by then.
On my old K0 I used the spring and ball bearing and the chap that bought the bike 5 years ago is still adding loads of miles and it is still going strong as, he keeps in contact 

Good point ...nice he kept in touch .... I just ordered the upgraded shift drum bolt parts from CMS via DS though while they are still available and not mega money, as I was ordering other stuff .. bet you used a new 'O' ring though Graham    .... the old parts will come in handy for one of my CB250's.

All of these years restoring Honda's a never yet ordered a sigle part directly from CMS.

[Trigger]

The rod was in the kit as it was a supersede part by then.
On my old K0 I used the spring and ball bearing and the chap that bought the bike 5 years ago is still adding loads of miles and it is still going strong as, he keeps in contact 

Good point ...nice he kept in touch .... I just ordered the upgraded shift drum bolt parts from CMS via DS though while they are still available and not mega money, as I was ordering other stuff .. bet you used a new 'O' ring though Graham    .... the old parts will come in handy for one of my CB250's.

All of these years restoring Honda's a never yet ordered a sigle part directly from CMS.

You should always ask me first, have at least 2 new ones here 

[Oggie400F]

Reading through Service Bulletin #4 (originally provided by BryanJ .. big thanks mate)... I spotted this in the pic. attached. Surely Honda wouldn't penny-pitch and tell you to re-use an 'O' ring. https://www.dropbox.com/sh/z8s0vpxu8niqva3/AAC1D8GaKGw_tvX0y2-CTcHaa?dl=0

It's interesting that the kit also contained a new --323-- clutch push rod......you know the ---323---one ..  it breaks into two pieces. Previously, as fitted on my own 500K0,  they used a CB450K1 onward ---292--- push-rod ('conventional' one piece steel part). I wonder what was wrong with the old style ---292--- push-rod and why that was changed and provided with the upgrade kit?

The original shift mechanism was obviously a carry-over design from the CB250/350K range as it's almost identical in design and uses parts common to the ---286-- engine.

Some background scary story here from the US about the gearbox/shift problem:-

http://forums.sohc4.net/index.php/topic,14675.msg1838670.html#msg1838670

This is the Kit for anyone who has never seen one: https://www.ebay.com/p/1522941856

Is this kit a recommended upgrade regardless of the current condition of a 500K0 clutch?
If so i will get one to upgrade mine as I proceed to get it back on the road.
Wish I had known earlier as I have just received an order I placed with CMS a couple of weeks ago. 🙈

EDIT.  I’ve just read the service bulletin and my engine is before 1018728 so does require the upgrade.  It doesn’t look like any of the engine cases or covers have ever been split/removed so doubt that this has been done.

[Bryanj]

Its worth taking the clutch cover off and looking first and/or removing the detent on the top to see what is in there.

My opinion on the pushrod is that the 500 clutch used to slip and the alloy rod was to reduce inertia in the mechanism