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Discussion Starter · #1 ·
Ok - moving along with this overhaul and now ready to install the camshaft into this CB350K3. Parts pic below.

Couple of questions:

1. there is a hole on one end of the camshaft, is this just an oil hole, or does it have some other purpose? There is a small pin oriented the opposite way on that end, so I think I'm good on the pin. Just want to doublecheck that this looks right.

2. I have an unidentified bolt and washer, see pic - what are these and where do they go? They were in the parts bag I labeled Camshaft parts along with the old shims that are also pictured... EDIT: just realized, this bolt and washer go in the end of the camshaft (right side as pictured below, the pin side). Right?

3. I sent my camshaft and rockers out to be refinished, and they were sent back with the pictured shims (the large ones). Do I use these new shims AND the old smaller ones? Obviously I need to check the end play with a feeler gauge but I am confused because of the size difference in these shims. Or, are the smaller ones required thrust washers that go... where?

4. Do you guys use loctite (blue or red) on your camshaft sprocket bolts?

Thanks
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Oil hole is good guess.

The Honda shims are hard to find. I wouldn't be a big fan of the ones sent with your cam. Racers don't usually use the shims. The shims help keep the engine a little quieter at higher rpms as the cam moves horizontally. Do your check for end play and use the Honda shims if possible would be my suggestion. I usually do this on the bench only the cam, gaskets and cam supports in place with the screws tightened with my 18V impact.

Yes to the loctite, your choice. Be sure the bolts go in the proper hole or your new cam will be toast. 6 foot pounds or 72 inch pounds is torque on the bolts if you are using loctite.
 

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Discussion Starter · #6 ·
Oil hole is good guess.

The Honda shims are hard to find. I wouldn't be a big fan of the ones sent with your cam. Racers don't usually use the shims. The shims help keep the engine a little quieter at higher rpms as the cam moves horizontally. Do your check for end play and use the Honda shims if possible would be my suggestion. I usually do this on the bench only the cam, gaskets and cam supports in place with the screws tightened with my 18V impact.

Yes to the loctite, your choice. Be sure the bolts go in the proper hole or your new cam will be toast. 6 foot pounds or 72 inch pounds is torque on the bolts if you are using loctite.
Boomer - do you not like the new shims because they are larger in diameter, or...? I guess I am confused about why they sent me shims that must clearly go on the other side of the cam, as opposed to the older smaller shims. Any tips on where to put the shims exactly? Thanks
 

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Shim the tach side then if needed add a shim to the other end. As mentioned I do the shim fitting on the bench before final assembly then check after install to be sure I am not too tight. The shims are not a critical piece on these engines. Loose is better than tight.

Check the fit of the larger shims on the cam. How much clearance is there? It should be minimal, if not it will tend to act like a hola hoop. A poster on the other board sourced some that actually had closer tolerances than the OE ones although they have a larger outside diameter.
 

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Discussion Starter · #8 ·
Shim the tach side then if needed add a shim to the other end. As mentioned I do the shim fitting on the bench before final assembly then check after install to be sure I am not too tight. The shims are not a critical piece on these engines. Loose is better than tight.

Check the fit of the larger shims on the cam. How much clearance is there? It should be minimal, if not it will tend to act like a hola hoop. A poster on the other board sourced some that actually had closer tolerances than the OE ones although they have a larger outside diameter.
I feel so dense about this. If I understand correctly, the shims must ride on the end of the cam (either side, doesn't matter) where I have the pick tools positioned in below picture correct? The larger shims that came with my refinished cam fit there, though they are just a touch on the loose side, as you warned against, but the smaller Honda shims from what I can tell could only possibly fit on the tach side inside of the tach housing, riding on the very end of the right side of the camshaft? Do they get doubled up there if necessary?

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I'm reading every post I can find on this and for some reason it just isn't clicking for me...

When I am ready to do the axial end play check, I need to assemble the cam (do I need to go ahead and install the cam sprocket bolts as well in that step?) in the head and use the tach and points cover gaskets as well. Right?

This is the state of the motor. Anything look amiss?
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Getting close, but this bit is really throwing me. Thank you!
 

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For your situation I would suggest the following ....

Have the 2 cover gaskets oriented correctly on their respective covers. For final assembly the gaskets will be on the engine, not on the cover FYI.

Feed the camshaft in through the cam sprocket, good practice for the final assembly. Do not put in either cam bolt. Do not put in any rocker shafts or rockers.

Put the points cover and the tach cover in place with the gaskets. Put in the four screws on either end to the same tightness as final assembly ... this is where I use my impact.

Measure the end play with your feeler gauges .... again this is not super critical. You then add the shims, start at the tach side. If another one is required put it on the points side or stack it with the other one on the tach side. I have seen them both ways. If no shims are required then that's fine. If your cam is original to all the other parts you could just install the shims that you removed and check carefully with a feeler gauge.

This is actually the easiest part of the cam assembly so be prepared ....

Do you have new o-rings for the rocker shafts? Common point of leakage if they are not replaced.
 

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Discussion Starter · #10 ·
For your situation I would suggest the following ....

Have the 2 cover gaskets oriented correctly on their respective covers. For final assembly the gaskets will be on the engine, not on the cover FYI.

Feed the camshaft in through the cam sprocket, good practice for the final assembly. Do not put in either cam bolt. Do not put in any rocker shafts or rockers.

Put the points cover and the tach cover in place with the gaskets. Put in the four screws on either end to the same tightness as final assembly ... this is where I use my impact.

Measure the end play with your feeler gauges .... again this is not super critical. You then add the shims, start at the tach side. If another one is required put it on the points side or stack it with the other one on the tach side. I have seen them both ways. If no shims are required then that's fine. If your cam is original to all the other parts you could just install the shims that you removed and check carefully with a feeler gauge.

This is actually the easiest part of the cam assembly so be prepared ....

Do you have new o-rings for the rocker shafts? Common point of leakage if they are not replaced.
Thanks for this info, makes sense. Mostly. The only question I still have about the shims (again, I know I am probably being really dense here) is: the smaller Honda shims go at the very end of the camshaft, and ride INSIDE of the tach housing right? Basically I'm just confused about the two different shim sizes... the large ones clearly go right next to the cam lobes at either end (where I have the pick tools positioned in my previous post picture), but the small shims from what I can tell could only possibly fit on the tach side inside the tach housing itsef at nearly the very end of the camshaft, though you mentioned that I could double them up OR do one on each side - This is what is tripping me up. I don't see how I could do one of the smaller ones on each side? Where exactly would they ride? I took the motor apart two years ago and I don't have any idea where the shims were originally.

For the rocker shaft o-rings, thanks for that tip - I don't have new ones. Will hardware store o-rings of the appropriate dimensions suffice, or do I need to source something special for those??
 

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Discussion Starter · #14 ·
Yep - I called around a couple of Honda parts counters today and no one has them. Found some NOS o rings for sale on ebay so ordered those...
Actually - just realized, looks like I ordered a different part #, but the dimensions appear to match: 913313-393-003

Those will work, or no?
 

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Discussion Starter · #15 ·
Actually - just realized, looks like I ordered a different part #, but the dimensions appear to match: 913313-393-003

Those will work, or no?
Update: just spoke to local parts counter again, according to them the 7.8x2.2 (Honda #91308-283-000) o-rings have been superceded by Honda part #91301-pc9-003, which is slightly different dimension 7.7x2.3 o ring. But according to the parts guy either size is fine to use. And I looked again at what I ordered and they are 7.8x2.2, so I guess I am ok. But it does seem like there are a lot of possible part numbers for these o-rings, and a couple different acceptable dimensions (all very very close to each other). Do your own research, obviously, but posting here just in case this is useful info for anyone else in the future trying to hunt down these rocker shaft o-rings.
 

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Discussion Starter · #17 ·
I know, I have had that page open for a week it seems. My confusion I think really stems from the size of the small diameter old shims (further up this post) - they can't possibly fit where that diagram in the manual shows the shims going. Not even close. But the new ones can fit there, they are the right size. So I am going to use the new ones only (if shimming is even necessary) and I am not going to use the old smaller diameter shims and I am not going to worry about it. But the mystery remains, and sort of makes me uneasy tbh: where were the old smaller diameter shims installed when i disassembled this motor way back when? Right now I have no idea.

I probably should not have taken such a long layover with this project, but sometimes that's how it goes.

Thanks,
 

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Just a thought...
Those shims...they could be for the spark advance, IF you had taken
it apart. I think the spark advance cam also had shims below it's cam.
(seeing as the shims are next to the bolt and washer)
 

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Discussion Starter · #19 ·
Just a thought...
Those shims...they could be for the spark advance, IF you had taken
it apart. I think the spark advance cam also had shims below it's cam.
(seeing as the shims are next to the bolt and washer)
Eureka!! That is exactly what those are! Man I feel better now, seriously thank you.
 
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