Are rocker arms of all years interchangeable

[Wtc5617]

I have a 72 Yamaha 650 xs2 that unfortunately was starved for oil on the top end requiring new rockers and camshaft. I bought a good condition used camshaft that is identical to mine (same number of teeth on timing chain gear). The seller did not have the rocker box that was manufactured with the camshaft.

So i need new rockers arms and shafts but they seem hard to come by on sites i have looked at. I have found “new” remanufactured rocker arms but are they any good? I hear the remanufactured camshafts do not perform as well as the original like the ones sold on mikes xs so i question if the rocker arms are the same?

Would it be better to just buy a used rocker box with the shafts and rockers, remove them and install in my rocker box? I would buy the best possible one on e bay as i did with the cam. But since mine is a 72’, do i have to buy only 72’ years of rocker arms? Or could i go buy a 80’ rocker box and swap the arms and shafts over?

I measured my rocker arms and shafts and they are within tolerance (0.004 in), pictures below configuration as if sitting on bike. Also i noticed my rocker arms have numbers on them, my left cylinder has the number 9 on both intake and exhaust while the right has 10 on both rockers answell, what’s that about?

To refine things, my questions are:
1. Are remanufactured, “new” rocker arms a good replacement for my original rocker arms?
2. If i bought a used rocker box and swapped the arms and shafts, will any year work to replace my 72’ ones?
3. What do the numbers on my rocker arms mean?


Any feed back is greatly appreciated, thanks!

 

[DogBunny]

72 and later rocker arms are all the same. Intakes are the same as exhausts. 1972-1983 are all the same.
The numbers cast into the rockers don't mean anything, they are just casting mold numbers.
Buying a rocker box is a good way to get rocker arms.

 

[Its been a long time]

If the rocker arms on your shaft are good, the running surfaces for the camshaft and the valve can be reclaimed. Basically, your rocker arms would be ground back, hard weld overlay and reground to the correct profile. It's a specialist job but I would do my own rocker arms instead of buying ones already reclaimed.

 

[Wtc5617]

72 and later rocker arms are all the same. Intakes are the same as exhausts. 1972-1983 are all the same.
The numbers cast into the rockers don't mean anything, they are just casting mold numbers.
Buying a rocker box is a good way to get rocker arms.

Thanks for the fast response, i think i will just buy a decent complete rocker box off e bay.

 

[Wtc5617]

If the rocker arms on your shaft are good, the running surfaces for the camshaft and the valve can be reclaimed. Basically, your rocker arms would be ground back, hard weld overlay and reground to the correct profile. It's a specialist job but I would do my own rocker arms instead of buying ones already reclaimed.

I’m not sure where i would go to get that done… i am located in Canada so shipping is expensive. I looked into getting my cam re-surfaced but the cost was way more than a good used one. I found a rocker box with the arms that look to be in great condition for around 100$ U.S. Is getting them re-claimed very common? Seems like a lot of these parts are untouched/ only normal wear.

 

[Its been a long time]

I’m not sure where i would go to get that done… i am located in Canada so shipping is expensive. I looked into getting my cam re-surfaced but the cost was way more than a good used one. I found a rocker box with the arms that look to be in great condition for around 100$ U.S. Is getting them re-claimed very common? Seems like a lot of these parts are untouched/ only normal wear.

For sure, if you can find a good used set that's your best option. Typically, a shop that hard surfaces and regrinds camshafts would be where you'd most likely get rocker arms reclaimed.