Cam Chain Guide Replacement Parts List

[smiles79]

Hi all,

I'm gearing up to replace the cam chain guide on my '75 and I was hoping to get some input on my parts list. I'm trying to get it all done for $400 or less, here's what I've got (all from Mike's XS):

Premium gasket and seal kit: 18-0001
Cam chain guide: 05-0006
Cam chain: 52-5021
Master link: 01-8815
Chain breaker: 35-0111
I'll probably get an engine stand from TC Bros as well, so this puts me at about $340.

I have a few questions as well:
Is it necessary to replace the cam chain or is it fine if it's intact?

Should I consider replacing the tensioner components? If so, which ones specifically?

Will I need to be able to remove the valve springs? If so, I'll have to buy that tool.

Will I need a tool to compress the piston rings to be able to get the jug back on?

Thanks!

 

[xjwmx]

I'm trying to get it all done for $400 or less,

If you're counting pennies, I don't know what the engine stand costs but it isn't needed. Just use a pallet, available free anywhere, and a rug that's worked itself outdoors.

P.S. I think I would try to replace the front guide by just removing the head cover. There's a good chance you wouldn't need new gaskets if it was successful.
Also, you can probably don't really need:
Cam chain: 52-5021
Master link: 01-8815
Chain breaker: 35-0111

I reused my chain with almost 60k on it -- because I've heard of engines going 80k before a rebuild and I doubt that the chain was the problem.

 

[5twins]

You seem to have most of your bases covered but let me fill in some missing items and recommend some alternate buying sources for others. I think we can save you some money. Let's run down your list ..... First, I don't recommend that gasket and seal kit. It's very expensive, just the topend stuff, it's missing some things you need (valve guide seals), and has others you don't (cam seals, copper washer set). It contains 4 of the original rubber/metal cylinder stud sealing washers which most of us replace with brass or copper washers. In fact, Mike's sells the brass ones and it's surprising they don't include those instead seeing that this is called a "premium" kit. The only "premium" I see about this kit is the price, lol. I recommend you just get a normal full engine gasket kit instead. It will include the needed valve guide seals and is about 1/3 the price, plus it has all the rest of the engine gaskets. And if you shop eBay, you can beat Mike's price by $10 to $20.

Front cam chain guide, yes, you'll need that, and Mike's is about the only option for a replacement. Hopefully you'll get one without badly off angled bolt holes, lol.

For the cam chain, I like to replace them if the motor has anywhere near 20K on it. If original, they're usually pretty stretched out by then. A badly stretched chain will have more of an impact on a points or Pamco equipped model because those items are operated by the cam. You will start running out of timing plate adjustment when the chain gets really stretched. For a new chain, I recommend buying it from Yamaha. It's cheaper and includes the master link .....

https://www.partzilla.com/product/yamaha/94500-02106-00?ref=3e83c4f1be116f05a4f2914f1b1ac63329a771b6

For a cam chain breaker/riveter, get one off eBay. Pretty much the same tool for 1/4 the cost .....

https://www.ebay.com/itm/13-PC-Cam-...800552?hash=item3b1050ca28:g:FzEAAOSwNNVbKbSj

You'll need a valve spring compressor tool as well to get the valves apart so the seals can be replaced. You may also need to do some hand lapping to seal the valves back up. Again, eBay has virtually the same tool as Mike's for a fraction of the cost .....

https://www.ebay.com/itm/5-Sizes-Va...67770734?epid=23013691449&hash=item2137a96b6e

I can't recommend that TC Bros. engine stand. I weld up my own which work wonderfully, but someone gave me one of those TC Bros. stands and I can tell you from experience, they're junk - ill fitting and a royal P.I.T.A. to install.

 

[5twins]

A word or two on the cam chain breaker/riveter. You'll mainly want to use it for the riveting, not the breaking. The pins on the cam chain are quite small which means the breaker tool pin is too. It's easily bent or broken. Instead, just grind the riveted pin ends off flush to the side plate and tap the link out with a punch .....

You can also try to pry the side plate off with a small screwdriver, or do a combination of prying the plate and tapping the ground off pins with a small punch.

It should be easy to locate the original riveted mater link. Yamaha did a pretty crude rivet job on it, lol .....

 

[xjwmx]

It should be easy to locate the original riveted master link. Yamaha did a pretty crude rivet job on it, lol .....

When riveting links, how much pressure on the side plate? How do you find a sweet spot between the sideplate flopping from too much play, and the link being stiff?

 

[5twins]

The end of the link pin is softer material than the rest of the pin. Only it flares out. I've never encountered a problem with the link ending up too loose or too tight, they've always come out just right.

 

[xjwmx]

Interesting! That's a question that's always plagued me.

 

[smiles79]

Thanks for all your gues' input! I'll look a little closer and do some more research after work.

 

[5twins]

The end of the pin that the plate fits on is also a bit smaller than the rest of the pin, stepped. The plate can only slide on the proper amount .....

 

[smiles79]

5twins, is 18-0202 the gasket set you were recommending?

 

[5twins]

That should work just fine. If you're not in a hurry, you may find something a little cheaper on eBay, but probably not much. Another item to consider are the stainless rocker shaft end caps. On the original chrome ones, the Philips screw slots usually get all rusted up. This stainless replacement set is $20 well spent I think .....

https://www.mikesxs.net/yamaha-xs650-stainless-steel-rocker-shaft-plug.html

 

[smiles79]

Cool, thanks! A couple more questions if you don't mind:

Is it worth replacing any of the tensioner components?

Will I need a tool to compress the piston rings to get the jug back on?

Do you have any recommendations for an engine stand, or do you have one you'd like to sell?

Thanks again for your time, I'm excited to dive I to this project and your help is much appreciated.

 

[5twins]

You shouldn't need to replace any of the rear tensioner parts, they hold up quite well. The blade doesn't fall apart like the front one does.

You won't need a ring compressor. See the last few pages and recent entrees in Mailman's XS2 resto thread.

Sorry, I have no recommendations for a stand, or extras for sale. If you have access to a welder, they're very easy to build. If this is a one time operation, you don't absolutely need one. Again, refer to Mailman's thread. He did his just propping the motor up with various wooden blocks. I've built myself a few because I have a couple extra engines sitting around and it's nice to have them on stands so they're easy to store and/or move around. What will work in a pinch is one of those $7.99 mover's dollies from HF. The engine will sit right down in it and also be easy to move around.

 

[xjwmx]

The end of the pin that the plate fits on is also a bit smaller than the rest of the pin, stepped. The plate can only slide on the proper amount .....

Lots less craftsmanship required than I assumed...