[ryot90]

Hello. I bought a 1979 CX500 a couple of weeks age. The title shows 10,000 miles, and the previous owner replaced a lot of the seals and just had the carbs rebuilt. After riding it for a few days, I suddenly noticed a knocking sound, but it wasn't bad. The next day, the sound was terrible, and I had no idea what to do.



I just started to check the cam chain today, and when I took off the timing inspection cover, I noticed a piece of plastic. I pulled it out and noticed there was another one farther down that I could reach with my finger, but the oil made it too slippery to grab. The piece was chipped, and would make sense for the source of the knocking sound in the bottom end of the motor, I think. Also, the plastic piece is curved, probably a cylindrical shape if it were whole, about 1/4 of an inch thick, and appears to have metal on the "inner" surface. Does anybody have any idea what this could be a piece of? I want to try to order the piece if possible before I drop the engine out to check everything else.

 

[Shep]

Sounds like the cam tensioner and or the cam chain guide/s.



4 and 12 on here,



http://www.cmsnl.com/honda-cx500a-1980england_model16465/partslist/E16.html



You need to get the engine out and also make sure no metal debris has got around the engine e.g get the engine fully flushed and cleaned internally.Failure to do so could cause metal particles to get into the big-end shells and ruin the engine.



Start reading here,



http://choppercharles.com/cs/forums/145871/ShowPost.aspx



Hopefully some one else will point you to where to get the parts including a new cam chain.The cam chain can be got from Georgefix,



http://cgi.ebay.com/ebaymotors/CX50...9729058QQptZMotorcyclesQ5fPartsQ5fAccessories



Note:The Guides and tensioners are the same for all CX500 and GL500 none turbo models and the cam chains are the same for all models.

 

[ryot90]

Sounds like the cam tensioner and or the cam chain guide/s.



4 and 12 on here,



http://www.cmsnl.com/honda-cx500a-1980england_model16465/partslist/E16.html



You need to get the engine out and also make sure no metal debris has got around the engine e.g get the engine fully flushed and cleaned internally.Failure to do so could cause metal particles to get into the big-end shells and ruin the engine.



Start reading here,



http://choppercharles.com/cs/forums/145871/ShowPost.aspx



Hopefully some one else will point you to where to get the parts including a new cam chain.The cam chain can be got from Georgefix,



http://cgi.ebay.com/ebaymotors/CX50...9729058QQptZMotorcyclesQ5fPartsQ5fAccessories



Note:The Guides and tensioners are the same for all CX500 and GL500 none turbo models and the cam chains are the same for all models.

Okay, thanks! I'll be sure to do all of that and check the other parts too.

 

[bear351c]

100% agree. Sounds like a piece of cam chain tensioner/guide.

 

[kingston73]

Once you get the engine out and open you'll probably find something that looks a little like this:

Hopefully you caught it in time so your engine case doesn't look like this:

 

[morrow]

From what i've seen, getting that 'grinding' on those aluminum spots and that 1 bolt is pretty normal, even for an engine with low miles like 10k. As long as the tensioner and guides aren't broken and worn just make sure the cam chain is adjusted and go!

 

[ryot90]

Okay, I haven't been on here in some time, but that was due to a financial situation and not having any time to work on the bike. I took the engine out yesterday, and took it apart today.

The problem is the cam tensioner. It is shattered into 4 pieces that were scattered throughout the interior of the engine.



Good news: No metal shavings or places grinded down. The gears don't look worn, so I caught the problem right as it started. (THANK GOD!)



Bad news: I'm having difficulty finding the part (A couple on ebay looked pretty good) They are about $25, which seems reasonable. Also, the gaskets got ruined while separating parts (I knew that was going to happen) would the "Make-a-Gasket" stuff work, or is there anywhere I can get a set of gaskets for the engine?



Thanks for all the help!

 

[marshallf3]

As I read through this post I see the cam chain as available but does anyone still sell all the guide parts that are prone to breakage?



I have terrible luck with anything inside an engine that's made from plastic and wouldn't mind having a spare set around, I might get lucky and catch a breakage in time as well. From what CXOkie has seen in the areas he's had mine apart we're pretty sure the 12,000 miles shown on the odometer is correct but time is an enemy of plastic.

 

[bear351c]

I ordered a "kit" for mine. (Australia) It had the plate, the blades, tensioner and even a new bolt, to replace the one that gets ground down.

 

[Reg in Bristol]

Good luck finding the parts



'make a gasklet' I assume its stuff in a tube?

silicone or similar ?

If so, its not advised.

A few of us have been caught out by that one and fitting the rear cover without a gasket

and relying on some paste can pinch the gear change and/or starter shaft.



I bought a roll of 0.8mm gasket paper from Ebay ages ago and make my own

Its quite good fun and cheaper/quicker than buying them

 

[Blindstitch]

Get a gasket from the nearest honda dealer, ebay, Bike bandit or other. Besides head gaskets the rear cover gasket is the only one I really believe should be replaced with a stock gasket. If you skimp then you will have to drop the engine again and do it over. Not my idea of fun.

 

[Shep]

If you cannot source the parts new put a call out in the For sale/Wanted section.I've re-used 2nd hand ones in my engines that I tested by trying to break with my hands.You can bend until near destruction and see if there's any weakness.

What happens to destroy them is more often than not the lack of cam-chain adjusting done by PO's which is also the main cause of the demise of these engines.Under normal well maintained conditions the guide and the tensioner don't actually take a massive amount of force but if the cam chain is not adjusted to take up it's slack then it starts to slap and batter the guide/tensioner.



In this example from Peter's original owned high mileage bike he has not changed the Cam chain guide and tensioner TTBOMK in over 140,000+ Klms.





http://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=20&t=289



Do tappets and cam-chain adjust with oil change between 3,000/4,000 miles and you should have no problems.



http://www.pdsrecording.site90.com/cxgl500/OilChange.htm



http://www.pdsrecording.site90.com/cxgl500/CXGLTappets.htm#CXGLTappets







HTH

 

[ryot90]

Okay, I've found a person on ebay selling what appears to be a kit that will fit the bike.

http://cgi.ebay.com/ebaymotors/Suzu...36QQptZMotorcyclesQ5fPartsQ5fAccessories#shId



It says for Suzuki, but I looked at the pictures, and they appear to be the same size as mine, I think it was a mis-label.

I also found some of the paper gasket stuff. I didn't even think there was anything like that out there!



For now, is there anything else that yall would recommend I do since the engine is out? The inside looks pretty good, and I'll try to get some pictures up today. But I figure that since I've got the engine out, I might as well do pretty much a full overhaul while I'm here. Thanks again!

 

[Reg in Bristol]

Well spotted its the CX manual cam chain gubbins alright



For the cost its worth sticking a new oil seal in the rear cover

If the stator tests out Ok then I'd leave it be

ditto the mech seal which can be done in situ anyway



Dont lose the small washer on the splines behind the Impellor !



I'd clean up and use some copperslip on the locator tubes on the water pump cover

these buggers often seize in which tempts folk to use cruel and unusual punishment

getting them off and thereby breaking them.



Dont ask me how I know ok?

Nobody saw me do it

you cant prove nuthin

 

[ryot90]

Okay, So another thing I realized is that since the crank spun independently from the cam, the timing is gonna be way off. I don't have the tool to remove the flywheel, but I'll get it from my cousin next weekend when I (hopefully) have the parts.





Okay, so I was mistaken, the bolt is worn down. But it doesn't look too bad.

Here is below the flywheel.

The rust is from sitting for a week, I've sprayed WD-40 on it, but before I put it all together I'll use a toothbrush to get the rest of the rust out.

That's what I've got so far.





Here's a pic of the bike before removing the engine. She's in really good condition.

 

[marshallf3]

Okay, I've found a person on ebay selling what appears to be a kit that will fit the bike.

http://cgi.ebay.com/ebaymotors/Suzu...36QQptZMotorcyclesQ5fPartsQ5fAccessories#shId



It says for Suzuki, but I looked at the pictures, and they appear to be the same size as mine, I think it was a mis-label.

I also found some of the paper gasket stuff. I didn't even think there was anything like that out there!



For now, is there anything else that yall would recommend I do since the engine is out? The inside looks pretty good, and I'll try to get some pictures up today. But I figure that since I've got the engine out, I might as well do pretty much a full overhaul while I'm here. Thanks again!

It may be worth investing in a full gasket kit, I've seen two major variants advertised on eBay and one goes on and on to explain it has everything down to the last O-ring. One was like $55, the other was over $100 if I recall. Can't remember which was which though.



Even if you only used a few of the gaskets the kit would probably pay for itself.



There was a project going on on the old forum site, may be in the top sticky or dropio site now, where a guy was scanning in every gasket he could that made perfectly printable patterns for them. All you'd need then would be a very good set of tin snips (not the cheap ones and scissors may not work well) and X-Acto knife for detailed areas and a set of those leather hole punches you can get at most wholesale tool stores.

 

[marshallf3]

So Shep, I take it from what you're saying is that if I keep a close eye on the chain and other adjustments I probably shouldn't have much of anything to worry about for quite some time since it's still a low mileage bike?

 

[TonyG]

Okay, I've found a person on ebay selling what appears to be a kit that will fit the bike.

http://cgi.ebay.com/ebaymotors/Suzu...36QQptZMotorcyclesQ5fPartsQ5fAccessories#shId



I also found some of the paper gasket stuff. I didn't even think there was anything like that out there!



For now, is there anything else that yall would recommend I do since the engine is out? The inside looks pretty good, and I'll try to get some pictures up today. But I figure that since I've got the engine out, I might as well do pretty much a full overhaul while I'm here. Thanks again!

Discount Honda gives members of our forum a 10% discount on their already reasonable/discounted prices. If you choose to get the rear gasket, the oil seal and a few others, check the prices there. Check the information on the quick reference info about how to get the discount. http://www.discounthondaparts.com

 

[Shep]

So Shep, I take it from what you're saying is that if I keep a close eye on the chain and other adjustments I probably shouldn't have much of anything to worry about for quite some time since it's still a low mileage bike?

I don't see why not.As he said there's no metal in the oil it's been caught in time.I'd still do my trick after the re-build of running cheap 20w50 mineral oil+ new filter up to thermostat opening temp or 25/30 miles riding then dump and put another oil filter and fresh 15w40 diesel engine oil in.



Oil and filters are cheap,cranks ain't

As Don says it's worth renewing the seals as that rear Water pump one almost always goes on stood engines when you refit the rear case but in regular use they almost never go.



The biggest crime against these bikes and any bike is it being stood and not used.Low mileage ain't all it's cracked up to be

Note to OP.Make sure the oil filter Spring and washer are present.If the bike has had this neglect I suspect they may have been left out as well and they are,"System Critical" even though they are small cheap components.

 

[ryot90]

It may be worth investing in a full gasket kit, I've seen two major variants advertised on eBay and one goes on and on to explain it has everything down to the last O-ring. One was like $55, the other was over $100 if I recall. Can't remember which was which though.



Even if you only used a few of the gaskets the kit would probably pay for itself.



There was a project going on on the old forum site, may be in the top sticky or dropio site now, where a guy was scanning in every gasket he could that made perfectly printable patterns for them. All you'd need then would be a very good set of tin snips (not the cheap ones and scissors may not work well) and X-Acto knife for detailed areas and a set of those leather hole punches you can get at most wholesale tool stores.

The gasket set is $80 on ebay, and looks good. I couldn't find the scans in a brief search, so if I cant find them anywhere tomorrow, I'll just order the kit.