[darrenpage]

Hi all. I started my bike up this evening.... No drama for a minute or two as it burbled away then a nasty noise started up like a hard fluttering sound. This came and went until the bike had warmed up completely at which point the noise disappeared again. I don't have much experience with CXs but I guess this is the cam chain tensioner going west? The bike is one of the late uk models with an auto tensioner so there is nothing externally to adjust.



Am I right in assuming it's now an engine out job and replace the chain etc before something expensive happens?

 

[darrenpage]

Hi, yes I'm in the UK - Stoke on Trent. The bike is an 81 model Eurosport and showing 24500 on the clock but I can't comment on how genuine that figure might be. The previous owner told me the engine had been split recently for a new stator but this was before he purchased it in early 2010. I,ve not had the rocker covers off as there is no tappet noise and whilst I wouldn't say the carbs are perfectly in synch its not running badly. I tried killing the ignition a couple of times and restarting it this evening. Once the noise resarted instantly and once the engine was quiet again for a short period. Revving had the same effect - sometimes the noise went sometimes not.



Cheers



Daz

 

[darrenpage]

Funny you should mention You Tube - I had a look last night and found a couple of rattly CX posts - mine definitely didn't sound like the ones posted. I've come to work on it today - IPhone at the ready to record the noise. Guess what? yep not a murmur from it today. It ran superb from start to finish. I'll try again later.



By the way it has a pattern collector and Jama silencers which I think are actually designed for the A or B type CX.

 

[darrenpage]

Hi all,



Thanks for the input so far.



As requested here is a link to You Tube - http:brum brum clatter clatter clunk



The audio isn't bad - at least not on the IPhone I recorded it on anyway..... you can here the noise pretty well.



As of 12.30am UK time the link isn't live as You Tube are still checking the content for terrorist threats and illegal immigrants

Interesting thoughts on the exhaust system though - mine is kind of a bitsa of aftermarket parts.



Cheers



Daz

 

[darrenpage]

Hi all. Well that seems quite conclusive then. I'll attempt an engine drop on Sunday. One thing I picked up from the manual is the need for a Honda tool or " a 20 mm bolt of the correct thread pitch" to get the alternator off. Does anyone know if this is just a standard m20 thread?



Something else the bike did on start up last night - when I hit the starter first time round it didn't engage. The starter just span then sounded as though it was catching against the starter gear as it slowed. I had this once before on a Suzuki Savage 650, that time round it turned out to be 3 broken teeth on the starter ring gear. If that is the case here what would the chances be of a tooth fragment ending up in the stator or around the cam chain guides?

 

[darrenpage]

Hi guys. Many thanks one and all for the encouragement. It does sound straightforward but I'm a Brummy lad who's first job was nailing Austin Metros together at the now defunct Austin Rover factory - we were all taught the only tool needed to put one of those right was a Snap On hammer!



I'm afraid that doesn't translate well to motorcycle fettling so I've got everything crossed for a successful job.

 

[darrenpage]

Hi all. I decided to try and drop the engine today despite unseasonably early snow on the floor and me having no garage or shed big enough to work inside.



Well guys your advice has been spot on so far. Pottering along at a steady pace allowed me to get the engine out and the water pump off with no sues at all. I'll post a picture of the water pump impeller shortly for comment as the ceramic disc on the back face got left on the camshaft instead of coming away with the impeller as suggested in the manual.



Anyway, I'm now frustrated - the bolts for the back engine cover are out and the gasket seal has been broken but the rear engine casing is refusing to lift off. It's loose and will rock back and forth until there is about a quarter inch gap around the mating face but I've lost the light now so the fun has stopped. Having followed the manual which suggests the rear cover should just lift away can anyone offer advice on what might be making it so reluctant?



Cheers



Daz

 

[darrenpage]

Hi - thanks for the info Shep - looking at the diagram you supplied confirms my engine is this type.



Here's a picture of the impeller as removed. There is a small dig in the sidewall of the rubber cup that fits into the underside of the impeller and the the large + small ceramic washers were left on the camshaft when the impeller was lifted off. with a little cleaning these components have mated back together ok.

The small ceramic washer and the cast surface under the rubber cup were very grimy before cleaning. Does the rubber cup just act as a locator for the large washer or does it have a more technical function?





Cheers



Daz

 

[darrenpage]

Thanks guys and yes you did tell me! Serves me right for getting all big headed when the engine came out so easily. The only problem now is a week at work which will mean no more tinkering until next Saturday..... If we aren't frozen solid under a couple of foot of snow by then. If this is global warming in action I'll eat my crash hat!!!!

 

[darrenpage]

Hi all. I braved the weather and got the rear cover off this evening. Surprising how easy that was with the electronics removed!



Apologies for the poor quality of this photo light levels were poor and my phone doesn't have a flash - obviously the rotor has to come off yet but the cam chain tensioner looks fully extended to me.... What do you think?

 

[darrenpage]

Thanks Reg. Much better pictures. My tensioner is actually extended even further. The hole in the push rod body that is just appearing in the first photo is fully exposed on my tensioner.

 

[darrenpage]

Cracking. Thanks Bandit. It's a relief to find the innards don't appear to be mangled. A straight camchainectomy I can live with. Ill give the block a nice coat of silver enamel whilst it's out too.



Daz

 

[darrenpage]

Hi all,



The snow has disappeared so I've finally been able to strip off the alternator rotor and get a good look at the cam chain. First off the chain hasn't struck any bolt heads etc so that was nice. The auto tensioner was at the end of its travel and when I took the assembly apart this is what I found -

The blades look fine to me but look at the damage to the guide bonded to the tensioner - I guess it wouldn't have taken much longer for this to really do some damage.



By the way - this is what the bike looks like when its in one peice.

Cheers



Daz

 

[darrenpage]

Hi all. I finally got the bits I need to put the engine back together so I've made a start.



This going to sound very silly but I'm going to ask anyway.... Having not removed the camshaft sprocket carrier ( because I haven't got a deep socket that will fit) how can I be sure I have the valve timing correct and not 180 degrees out?



I'm 99.9% sure it's right and as such I've refitted the cam chain and tensioner then gingerly rotated the crank through a four or five revolutions. Everything rotates fine with no valve piston crown interface issues. Is it safe to assume or should I stop being tight and buy a deep socket?

 

[darrenpage]

Hi Reg. Yep I agree the thing that suddenly worried me is that with the sprocket carrier washer and nut in place you can't see the camshaft drive pin. The manual states this should be at the 2 o'clock position for correct valve timing when replacing the cam chain.

 

[darrenpage]

Hi guys just to tie this thread up..... Engine now back together and in the bike again. It's running as sweet as sweet can be. Many thanks for all the help and advice. Star tip has to be the shep method for the mechanical seal. Makes a tough looking job the work of 5 minutes.

 

[darrenpage]

Thanks for the good advice guys. Shep you are right about those zen moments..... This little project has brought me closer to the bike and given me a sense of what a nice piece of engineering Mr Honda put together.



The shake down run this afternoon was great even though the temperature is only just above freezing. I'm going to enjoy my handy work this year.