[MGR1]

Hi all.



I plan to take out the engine on my '78 CX to change the tensioner, guide and camchain. As I posted before it seems the tensioner is near the end of its travel, and I suspect it may have sagged or could be broken.



I spoke to the first owner yesterday (he's 66 years old now), and he verified that the bike only had little over 5000 miles on the clock when he sold it. He owned it for 24 years, and it stood for 20 years in his heated garage without beeing started. I asked why, he said he had 25-30 other bikes at the time

. He could also verify that a Honda camchain kit was installed on warranty during the first year he owned the bike. I can see through the rear cover inspection hole that it has the new type of bracket.



I have checked with several suppliers, and it seems the camchain guide (14600-415-305) is unavailable. Have I got the right partnumber? If so, does anyone know a supplier that has it in stock? I have already contacted David Silver, CMS and John Oldfield.



Also I plan to change these parts:

Canchain 14401-MA1-013

Tensioner 14500-470-751

Mechanical seal 19217-611-000

Water pump oil seal 91202-283-013

Also rear cover gasket and other gaskets/seals that will be disturbed.



I have two further questions. Are the new Honda stock parts good, or should I rather seek out old, NOS parts? I ask because in my experience NOS parts are often better made than new parts, at least that is valid for the old brit bikes I usually tinker with.



And should I check/change something else when the engine is out?



Regards,

Michael

 

[Shep]

You are looking for,"Insurance" against faulty or sub-standard parts.No one can give you this.A genuine Honda part could well have been on a shelf for 10 years or more and decayed by age even if not in use.A NOS part could be low quality,no one really knows.

On the bright side I have re-used decent 2nd hand Cam chains,tensioners and guides with no ill effects.I check them for cracks and damage and stress them in my hands to look for any weaknesses.One of my Engines has new ones from David Silver and no problems.I have spare 2nd hand ones from basket case engines that I would not hesitate to re-use.



Consider this.There are thousands or possibly of hundreds of thousands of these bikes still on the road all round the world using whatever parts people can get and they are still going strong.Yours is a very low miles bike and the parts may not be that worn but I think you are doing the right thing by changing these parts especially because of the price you paid for the machine.D.I.D cam chains have a great reputation.



This will give you your own known,"Service" point so you know what work has been done for sure.As important after any work is continual routine maintenance such as pre-emptive oil and coolant changes,cam chain adjustment and keeping tappet gaps good.



Don't worry too much and just buy parts from known good sellers.In the UK Wemoto,John Oldfield and David Silvers are superb.



Put your model/year in the box

http://www.wemoto.com/bikes/Honda/CX_500_A/79-80/



http://www.davidsilverspares.co.uk/



http://www.johnoldfield.co.uk/



As for changing anything else if there's no problem with the Stator leave it be I would however just again to make my own service point change the oil pump chain and clean the sump and oil pump strainer.Doing all of this and you most likely won't have to open the engine again for 50k miles+.



Click here as well,



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

 

[MGR1]

Thanks for the info and links Shep. Yes, I think I will clean the sump as well. As for changing parts, I don't want to change anything unless it is necessary. If the stator looks OK (not burnt) I will leave it.



Regards,

Michael

 

[Blindstitch]

Ok i'm curious. If the PO only put on 5,000 miles how many did you put on?

Any chance you can take a picture of the tensioner hole because a new chain isn't going to stretch sitting there in the garage. The tensioner would have to be broken for it to look expired.

 

[MGR1]

It had 5485 miles on it when I collected it. It has now 6345 miles. I adjusted the camchain when I brought it home. First I looked inside the inspection hole with a small mirror and noted the position of the tensioner. The bottom loop of the hole in the tensioner was slightly visible, about 1 mm I would estimate. I adjusted as described in the Honda manual, and checked again. The hole was more visible now, about 3 mm's I would say.



I have looked at pics on this site, and elsewhere on the net, and am confident that I am looking at the right thing.



I do not really need to do this since there is no noise and (as far as I can tell) no metal flakes in the oil, but I would like to open it up just to have peace of mind, and as Shep said, make a "service point". If the hole in the tensioner wasn't visible I would have left it alone for sure.



Regards,

Michael

 

[Blindstitch]

Well when you get done tell us the price of piece of mind.



Mine was somewhere between $100-150 usd. and yes it was very needed.



Chain was expired, broken guide and I don't even know how the mechanical seal wasn't leaking. The oil seal fell apart in my hand.

 

[Shep]

Well when you get done tell us the price of piece of mind.



Mine was somewhere between $100-150 usd. and yes it was very needed.



Chain was expired, broken guide and I don't even know how the mechanical seal wasn't leaking. The oil seal fell apart in my hand.

As you know Don.A low mileage bike doesn't mean it has no problems.Oil seals and O-rings can last a 100,000 miles+ in constant use and can degrade in 5 miles if they have not been used in 15 years.Engines need to be run on a regular basis and why I'm against,"Winterising" where possible.Engines that are stood will decay as will the carbs.



You can see it every year,"come-the-Season" on loads of bike forums."I've just taken my bike out of storage and X/Y/Z is wrong".



Even one half decent ride a month will prevent a lot of this.Even starting the engine and running the bike up and down the drive-way once a week is better than nothing as it will help keep the clutch plates from binding and the brakes too.Don't get me started on electrics decaying on stood bikes as even they and their contacts like current to flow through them.

 

[MGR1]

Here is my best shot:

Unfortunately my camera did not allow better pics.

 

[Blindstitch]

Would be nice to see a better picture but you are right that doesn't look right for low miles.