[CheeseGromit]

Hi all, I know I have created many threads and questions over the past few weeks, it's a steep learning curve for me and I really appreciate the expertise and knowledge on this forum

I've decided that before I continue with my CX500 I would like to strip the engine down and examine the cam chain / tensioner / stator before continuing with anything else.

Apart from the flywheel M20 bolt, fan bolt and the clutch nut tool, is there anything else that I will need?

Also, I assume as I am there it would make sense to check the big end bearings? I'm making the assumption that it's ok to take them off, examine and put back on again? Any tips?

Thanks!

 

[Newt]

Hold on a minute......

I haven't chased down all your threads and questions. How many miles or km are on this bike?

Cam chain/tensionor condition can be checked without disassembling the engine. Use a dental mirror inserted in the inspection hole.
Stator condition can be checked without disassembling the engine. Use a multimeter to check the resistances as defined by the stator check procedure.

Connnecting Rod bearings (Big End) are not likely to have damage. There are methods to check these bearings without disassembling the engine. Why do you suspect the bearings have problems?

On the other hand, if you are jonesing for something to do...there is nothing stopping your endeavor to take the engine apart.

 

[CheeseGromit]

It only has about 30k and I did not have any intention of digging in to the engine, however after I noticed that the tachometer drive had disintegrated (the worm gear on the cam), that combined with not knowing the exact history of the cam chain and also wondering where all those tacho drive bits have gone made me re-consider, just for peace of mind I think it's maybe worth checking out the basics (inc oil pump filter etc).

 

[Newt]

You could pull the front engine cover to have a close look at the oil sump, oil pump and pump screen. Any bits or swarf in this area can indicate a problem area. If there is no bits or swarf, then you likely don't have a problem.

Another path is to remove the oil filter then cut it apart. Spread the pleats to inspect for debris.

You could inspect the cam chain tension and general condition with a dental mirror.

Would you opt for heart surgery on the suspicion you have a bad heart? Or would you want to perform less invasive tests and checks first?

 

[CheeseGromit]

When i got the bike I did not see any metal specs in the oil filter (I cut it open)/housing etc, however, after checking the fresh oil (I have only ridden for about 1 hour, most of the time has been trying to sort the carbs out, stop start etc) I did notice some specs in the oil. None of them are copper. All silver. Oddly, a magnet does pickup a very small amount of material (looks black, tensioner?).

This has to be coming from somewhere, but I have other things going on which could have contributed, for example, I adjusted the manual tension twice (all done to the letter and checked with an endoscope), replaced the gasket on the tachometer drive cover (maybe I disturbed some old broken fragments) also the clutch does not disengage 100%, so maybe parts of the clutch are getting in the oil?

I should have mentioned the above at the start of the thread but I wanted to keep it simple. Hopefully my concerns make more sense and give some extra context now.

Not sure if it warrants checking the bearings, but I think I should at least examine the other parts.

 

[CXPHREAK]

Aluminium and steel = camchain.

Adjust it per the FSM and do a mirror inspection as Newt said.

It may have gone unadjusted a couple of times but a fair likelihood the chain is fubared as it is chewing on the rear crank support {alluminium} and if you're getting steel one of the crank support bolts, maybe the chain cover plates and even nibbling one of the cover plate bolts.

 

[Newt]

Frankly, I wouldn't open the engine on a hunch.

Since the cam chain has needed 2 adjustments in a short span. I suspect the camchain chewed part of the case causing the "silver" bits. These are likely aluminum, not magnetic. There is a bolt which can suffer due to a loose camchain, this will be the magnetic bits. Did the endoscope inspection show end of adjustment? If you are not sure, then drop the engine and plan a camchain, tensionor and guide replacement.

I wouldn't go any deeper into the engine than needed. In other words, your con-rod bearings are likely good because you don't have any indicators to the contrary.

 

[CXPHREAK]

Not a hunch newt.

I've replaced maybe 30 camchains in these things now. I see the damage they do and can read the debris.

The hardened steel bolt grinds fine enough to go through the pickup screen. It then goes straight to the pump which is then scored to death lowering oil pressure and beginning the destruction of the motor.

Then you have the bikes with the filter assembled incorrectly and now the motor is effectively doomed as the stuff is now headed for the crank bearings and everything else. Or the filter hasn't been changed in forever and has collapsed putting the bypass valve into operation equalling the same thing.

These are almost indestructable engines. I've always said of the CX motor, they don't die - they're murdered.

But he should check with a mirror before pulling anything apart.

We've always advocated testing before anything else here.

 

[Randall-in-Mpls]

The steel you saw likely came from the chewed tach drive screw. You'll find the rest in the sump. If the screen and filter have been in place, I wouldn't be concerned about it.
Pull the front and rear covers to clean, replace chains, etc. Leave the rest alone.

 

[reclinedrelic]

To examine the cam chain, blades and stator you only need to remove the rear cover. If you are going to remove the front cover then you can inspect the oil pump and the oil pump chain.
To go deeper into the engine requires removal of the cylinder heads.
The deeper you go the greater the expense and time involved.
You can get some idea of the big end condition without dismantling the engine. How to check for a blown big end bearing using a screwdriver | MotoFaction

 

[CheeseGromit]

I will take the casing off and check out the obvious parts based on all the good advice above. I am not worried about taking the engine apart, I just need to make sure I don't get half way and then discover that I need a special triangular key to remove a cog etc

Regarding the bearings, based on what has been said above, am I correct in thinking that as long as there is no copper flakes/particles in the pan/oil/oil pump I can assume the bearings are in good condition, and it would be a better bet to leave them alone rather than check? The last thing I want to do is disturb them for no reason.

Also, the broken tachometer gear.. which way does the oil flow? I can see there is a tunnel with an o ring underneath the cam, does that go back to the sump or is that the flow from the oil pump? (just wondering where the bits would have gone).

Thanks again everybody, this would be 100x harder without the helpful people on this forum!

 

[CXPHREAK]

The O ring behind the cam bearing/tach drive is on the pressure line coming from the oil pump.

It must be a manufacture drilling vestige as the pressure gallery is actually blanked at this point and doesn't proceed into the cover..

As for special tools you'll need a way to lock the crank when undoing and retorquing the rotor {58 - 72 lb/ft}.

 

[bahn88]

Hi all, I know I have created many threads and questions over the past few weeks, it's a steep learning curve for me and I really appreciate the expertise and knowledge on this forum

I've decided that before I continue with my CX500 I would like to strip the engine down and examine the cam chain / tensioner / stator before continuing with anything else.

Apart from the flywheel M20 bolt, fan bolt and the clutch nut tool, is there anything else that I will need?

Also, I assume as I am there it would make sense to check the big end bearings? I'm making the assumption that it's ok to take them off, examine and put back on again? Any tips?

Thanks!

Not a special tool-but 6point (vs 12 point) sockets where possible.
Some bolt heads seem to be easily rounded-especially if been sitting for decades.
Many a 10mm/12mm oil filter bolt head has been rounded.......

 

[CheeseGromit]

Ok, thanks all!

I always use 6 point sockets where possible. I'll probably make my own tool for the clutch nut (maybe an old socket as seen online).


CXPHREAK, given that you have seen a lot of these scenarios, would you check the bearings at the same time or just leave them alone? (assuming I don't come across any copper bits inside the engine). I am leaning towards leaving them now.

 

[CXPHREAK]

Check your oilpump if you're going into the front cover..

It's going to be a guide. If your filter is correctly fitted your bearings are likely unscathed.

 

[CheeseGromit]

Great, thanks.

 

[Sidecar Bob]

You will need 3 torque wrenches, a 1/4" drive for all of the M6 screws, a 1/2" drive for the stuff that needs a lot of force like the flywheel bolt, clutch nut &c and a 3/8" drive for everything in between. You will also need the special pin wrench for the clutch nut if you take it apart (or like many of us you can alter an old socket for that).

And then there are the 2 bolts for pulling the fan and the flywheel (I'm sure someone will post the correct sizes). An impact wrench (either air or electrical) will make removing the flywheel much easier too, just make sure you don't tighten the puller bolt more than finger tight before hitting it with the rattle gun).

The tool for holding the crank while you tighten the bolt was mentioned but if you don't expect to need that often enough to merit buying the tool you can put a socket on a long L handle on the hex for turning the crank, let its end sit against the bench and have an assistant hold the engine while you torque the flywheel bolt. I prefer to tighten the clutch nut after the engine is in the bike so that I can put the transmission in high gear and tighten against the mass of the bike.

Oh, and don't forget the screwdrivers. You are likely to have assorted Philips drivers on hand but they are not suitable for working on anything made in Asia in the last 60 or 70 years. Philips invented his screw heads and drivers for assembly line production and designed them so that the driver cams out of the head before it applies enough torque to break it off, which can make it very hard to get the driver to engage well enough to undo a stuck screw. The Japanese figured out that if they used drivers with clutches the driver and head could engage positively so you could apply much more force to loosen a stuck one later on and the Japan Industrial Standard screw head was born.
Unfortunately, when you use a Philips driver in a JIS head it is as likely to cam out and damage the head as it is to actually turn the screw so investing in a set of JIS drivers is highly recommended.

 

[CheeseGromit]

You will need 3 torque wrenches, a 1/4" drive for all of the M6 screws, a 1/2" drive for the stuff that needs a lot of force like the flywheel bolt, clutch nut &c and a 3/8" drive for everything in between. You will also need the special pin wrench for the clutch nut if you take it apart (or like many of us you can alter an old socket for that).

And then there are the 2 bolts for pulling the fan and the flywheel (I'm sure someone will post the correct sizes). An impact wrench (either air or electrical) will make removing the flywheel much easier too, just make sure you don't tighten the puller bolt more than finger tight before hitting it with the rattle gun).

The tool for holding the crank while you tighten the bolt was mentioned but if you don't expect to need that often enough to merit buying the tool you can put a socket on a long L handle on the hex for turning the crank, let its end sit against the bench and have an assistant hold the engine while you torque the flywheel bolt. I prefer to tighten the clutch nut after the engine is in the bike so that I can put the transmission in high gear and tighten against the mass of the bike.

Oh, and don't forget the screwdrivers. You are likely to have assorted Philips drivers on hand but they are not suitable for working on anything made in Asia in the last 60 or 70 years. Philips invented his screw heads and drivers for assembly line production and designed them so that the driver cams out of the head before it applies enough torque to break it off, which can make it very hard to get the driver to engage well enough to undo a stuck screw. The Japanese figured out that if they used drivers with clutches the driver and head could engage positively so you could apply much more force to loosen a stuck one later on and the Japan Industrial Standard screw head was born.
Unfortunately, when you use a Philips driver in a JIS head it is as likely to cam out and damage the head as it is to actually turn the screw so investing in a set of JIS drivers is highly recommended.

I should have nearly all of those tools luckily, I was also planning on removing/torquing the clutch nut on the bike due to the issue you described, it sounds tricky on the bench.

Thanks for confirming and interesting read on the screws, i'll keep that in mind.

 

[bahn88]

You will need 3 torque wrenches, a 1/4" drive for all of the M6 screws, a 1/2" drive for the stuff that needs a lot of force like the flywheel bolt, clutch nut &c and a 3/8" drive for everything in between. You will also need the special pin wrench for the clutch nut if you take it apart (or like many of us you can alter an old socket for that).

And then there are the 2 bolts for pulling the fan and the flywheel (I'm sure someone will post the correct sizes). An impact wrench (either air or electrical) will make removing the flywheel much easier too, just make sure you don't tighten the puller bolt more than finger tight before hitting it with the rattle gun).

The tool for holding the crank while you tighten the bolt was mentioned but if you don't expect to need that often enough to merit buying the tool you can put a socket on a long L handle on the hex for turning the crank, let its end sit against the bench and have an assistant hold the engine while you torque the flywheel bolt. I prefer to tighten the clutch nut after the engine is in the bike so that I can put the transmission in high gear and tighten against the mass of the bike.

Oh, and don't forget the screwdrivers. You are likely to have assorted Philips drivers on hand but they are not suitable for working on anything made in Asia in the last 60 or 70 years. Philips invented his screw heads and drivers for assembly line production and designed them so that the driver cams out of the head before it applies enough torque to break it off, which can make it very hard to get the driver to engage well enough to undo a stuck screw. The Japanese figured out that if they used drivers with clutches the driver and head could engage positively so you could apply much more force to loosen a stuck one later on and the Japan Industrial Standard screw head was born.
Unfortunately, when you use a Philips driver in a JIS head it is as likely to cam out and damage the head as it is to actually turn the screw so investing in a set of JIS drivers is highly recommended.

Agree-these are popular locally-no I'm not the distributor

JIS Vessel Screwdriver Set - Japanese Motorcycle Screwdrivers

Vessel JIS screwdrivers. Made in Japan. Perfect for restoring or repairing Motorcycles, to include Japanese manufactured brands requiring JIS Screwdrivers

rhinotools.com.au

you also get what is in effect a "impact driver"-useful for CBs especially

 

[fsj]

I've been down this road, and currently still on it! The bike I bought had all kinds of invoices on the "servicing" it received. The first thing that set me off s the scenario Phreak described. The oil filter was put back without the washer and there were the same bits in the oil and filter as you described. This is just one of the major errors from the shops that "serviced" this bike for the previous owner. I feared exactly what Phreak was on about and anticipated the engine self-destructing. Murdered. I'm still running that engine. It sounds like a bag of spanners but other than that pesky vibration it seems strong enough. I'm building one to put in it's place. I'm tired of buying engines I don't know the history of. Tired of expecting the engine to be better than the one I took out only to find it needs at least the same if not more work and money than the one I took out. Peace of mind for me to just build one so I know where I stand with it and what to expect. Just my opinion.