Topic: '72 CB 500 clutch push rod

[trebot]

I have a broken clutch push rod and am having a h... of a time finding a new one. 
Are there any rods that are compatable ?  I may have to fabricate one from 7mm drill rod, but I'd rather find a stock rod.
Any help greatly appreciated !!

[Smudgemo]

Do you have both pieces on hand?  I'm interested in drilling out the broken ends to insert a rod and then silver-solder it back together.  No promises that it would work or be useful, but if you're going to throw it away and want to see what happens, I'd be game.

[Stev-o]

I have a broken clutch push rod and am having a h... of a time finding a new one. 
Are there any rods that are compatable ?  I may have to fabricate one from 7mm drill rod, but I'd rather find a stock rod.
Any help greatly appreciated !!

Yes, there is another bike that uses the same rod.   Look at the parts fiche for your bike to fertilize the part number.  Then google that number to find the part.

Good luck!

PS. I sold my 500, I was always paranoid I would break it!

[jonda500]

Honda CB450/500 DOHC twins use the same pushrod - I found one on fleabay and it's working perfectly in my 500F
John

[HondaMan]

I have a broken clutch push rod and am having a h... of a time finding a new one. 
Are there any rods that are compatable ?  I may have to fabricate one from 7mm drill rod, but I'd rather find a stock rod.
Any help greatly appreciated !!

If you opt to make one: use aluminum, not steel. This will greatly reduce the moving 'shift point' that happens with the clutch lever, because the engine width grows much more than the clutch rod as the engine heats up. An aluminum rod will grow closer to the same amount.

[oldfart]

Actually, no.  The four cylinder pushrod is aluminum with steel on each end, why it is prone to breakage (or separation).  The much earlier twin cylinder pushrod is solid steel.  The four cylinder pushrod was made dual material so it would expand at the same rate as the clutch, giving optimumly consistent lever feel and clearance.  The two rods will interchange, I and you have done it, but it ruins the designed-in temperature compensation.  There is a felka on the sister Euro SOHC board reproducing these pushrods, not sure but I think one-piece steel.  Also, CMSNL shows one -323 rod still in stock as if yesterday.

I did not see Mark's post.  Didn't mean to repeat that,  I was attempting to reply to the person who said the rods were the same.

[jonda500]

The pushrod I bought Is aluminium with steel at both ends, and was advertised as a CB450/500 twin pushrod. It looks identical to my original broken one but is between 1 and 2mm longer - being slightly longer caused no issues. With a new genuine honda clutch cable fitted and the marks lined up at the cylinder adjuster in the sprocket cover, I only need to have the freeplay adjusters wound out just a little.
John
p.s. Early model CB500 Fours also had an all steel pushrod.

[HondaMan]

p.s. Early model CB500 Fours also had an all steel pushrod.

That's right! You might be the first one I've met since 1973 that knows that? Mine was steel (1972, very early model, the ones where the "HONDA" logo fell off the alternator cover), but my brother's, bought 4 months later, was the aluminum-steel type. I gave up 'arguing' about it with the 500 Four owners years ago, because everyone thought I was lying... 

[Stev-o]

p.s. Early model CB500 Fours also had an all steel pushrod.

That's right! You might be the first one I've met since 1973 that knows that? Mine was steel (1972, very early model, the ones where the "HONDA" logo fell off the alternator cover), but my brother's, bought 4 months later, was the aluminum-steel type. I gave up 'arguing' about it with the 500 Four owners years ago, because everyone thought I was lying... 

HM - any idea why they changed material of the rod?

[HondaMan]

p.s. Early model CB500 Fours also had an all steel pushrod.

That's right! You might be the first one I've met since 1973 that knows that? Mine was steel (1972, very early model, the ones where the "HONDA" logo fell off the alternator cover), but my brother's, bought 4 months later, was the aluminum-steel type. I gave up 'arguing' about it with the 500 Four owners years ago, because everyone thought I was lying... 

HM - any idea why they changed material of the rod?

Yeah, they were trying to make it expand more, so the slip-grip point would be more consistent. There was a Bulletin that came out early on, stating that if the customer complained of this issue, to change the rods. This came out almost as soon at the 500 appeared!

[Deltarider]

The ends need to be hardened steel however. They undergo quite a load.

[HondaMan]

The ends need to be hardened steel however. They undergo quite a load.

Exactly. And, this is kind of hard to do well: I suspect it is one reason why they break?