Cam chain replacement

[Shaul Suhr]

G'day fellow bikers !
Can anybody advize me on the approximate distance in Ks that one should replace the can chains on a 1980 CB750 Custom Exclusive ?
<ine has done somthing like 50.000ks,and I can hear some  light chain noise, sort of light rattling, like its a tiny bit loose.
Worse at low revs, dissapears after 2000rpm. Also a slight knocking sound at idle, even after I pull in the clutch, seems from the bottom end.
Ive only just got this bike, as you all know, and its the second one like this Ive had, but Im not that mechanical, and dont have much of a clue ie: cam chains and bearings.
Can the cam chain be adjusted at all ?
Its winter here, lots of rain, and cold, but Im still on my bike 5 days a week at 6:00am. in the dark, and ridr 48ks each way to work. CB's are a reliable workhorse, and I want her to stay that way.
Could the oil be too thin ? I know these old bikes like thick oil, I use Castrol GTX 20/50, not sure what the previuose owner used. Coulf thinner oil make her noisey ? Does having an oil cooler affect what types of oil I can use ?
I seek the forums wisdom.
Ride to survive !
kiwibiker.

[Re-run]

Are you north island or south? If north, thats not winter! Thats like cool spring! See in my winter, my SNOWblower works more than a $10 prostitute! 


Anyways, works out to something about 32,000 miles or so and it might not be a bad time to replace the chain and check the parts for the tensioner soon. See if you can tighten things up a little and that might take care of it. I can say much about the knocking sound as I dont have a dohc but oil could affect that.
The 20-50 is actually probably a little thick. In your area, even in summer you probably don't go much above 80F. The standard 10-40 or even 15-40 would be just fine. Use a quality diesel oil and you got all the protection you need. I use rotella T synth and it is awesome stuff.

[Shaul Suhr]

Re-run, our cold is a damp cold. with frost quite a lot, it rains here almost daily for four months, or more some years.
North Island gets snow too, only not in the top half, we got lots of North Island Ski fields.
Diesel oil ?
Are you sure ?
Ive tried 10/40 oil in bikes before, seems t exasserbate any engine noise.
Id there an online manual showing the use of the cam tensioner ?
Cheers .

[Re-run]

Rain huh, try average winter temp of 0f or about -18C! And yes I would move if I could!

http://www.qdrive.net/viewfile/107534/31111
That should get you to the download for the manual.

One thing to understand is these old air cooled engines make noise. It is just the way they are. In all but your warmest temps, I would never use a 20-50 unless maybe with VERY hard riding. See what makes diesel oil good are not just the detergents but they have a greater zinc content like much pricier motorcycle oil.
So a diesel oil actually lends itself very well to motorcycles like ours.

I will have to remember that if I am lucky enough to move to NZ, top half, north island!

[vern401]

Yes R-R is correct. Diesel oil is quickly becomming the favorite to allot of forums that deal with these older bikes. Auto oil does not have the zinc in it that the diesel does because it is believed it messes with the cad converter.

[Shaul Suhr]

Holy sheep shit !
Spread the word !
What you are saying makes sense RR. vern also agrees.
I quite regarded bike mechanic today told me that Castrol GTX20w50 is what these older mikes like, so who do I belive ?
Ive been useing GTX in my bikes for 28 years now, and never had any problems with it.
It makes the motors run quiet, and stays clean a good month or more before it gets too dirty, thats 2000 ks for me, as I clock up about 98ks five days a week.
Yje Diesel oil thing makes a shitload of sense, the extra silicone would improove lubrication, much like the lead in petrol and oil used to.
I'll look into it for sure.
And yep, the old air cooled motors are noisey, thats how come we can learn to "listen" to our motors, and tell if somthing is loose. My old CX500 Custom had a lovely quiet motor, due partly I'm sure to its coolant jacket.
That mechanic, he says he can do my cam chains for NZ$400.00 , how does that compare with prices in the U.S ?
 Live to ride, ride to live !

[Shaul Suhr]

Hey ReRun, I tried to dowload that manual, mo joy mate !

[vern401]

Castrol GTX is great oil. I use it in my car and in my CX. My CB 750F and SL350 I run Diesel oil. The Ninja well it will get Castrol. If you know these bikes you will probably see that I use the castrol on the water cooled systems and diesel on the air cooled. My Air cooled seem to like it better.

[Re-run]

Yeah I just checked it and the manual must have got hit hard this month as the host bandwidth got maxed.
Not exactly ideal so I am going to find a secondary. It should reset soon but I will find another place and put up the links.

Edit: Working on it now. Found another site. Will probably use both. Problem is that many of the manuals are on my home pc which I will not have till tonight.

[Shaul Suhr]

So what is the heat rande of Diesel oil ?
Winter mornings here get down to between 10 & 0 celcwus, we get frost, maybe not snow, but very cold frost.
Im just concerned that the deisel oil may yake to long to pump up to the top end.
Does haveing an oil cooler have any affext ob what type of oil one can use ?
Sounds like a nice collection Vern.
Kiwibiker

[Re-run]

Well the first number is the important part for cold. The lower the number, the faster it flows.
So the 5-40 rotella will actually flow very well at those temps. The 20-50 will look like tar almost.
The second number is the resistance against heat breakdown. A 40 weight is good for all but the highest heat in a motorcycle. Say if you are in the Oz outback and it is extremely hot, then a 50 weight would be better. So for your range, i would still go with a 5-40 diesel. But then I have used it and was very pleased with the results. Shifts for so smooth and the engine was actually pretty quiet.
You can still use the 20-50 in summer if you want but for winter, a lighter oil would be better.

[Re-run]

Shaul, an alt download should be up now. Give it a try.

[sgtslag]

An oil cooler will NOT affect what type of oil you can/should use.  It will only cool the oil.  My '79 CB750K DOHC has an oil cooler that I installed.  It dropped my oil's temperature, coming out of the engine, from 250 F, to 190-210 F, while riding two-up, with luggage, in air temperatures of mid-80's F!  Dino oil begins to break down into carbon sludge at temperatures of 250 F+.  An oil cooler will extend the working life of dino oils dramatically.

This Spring, I will be switching from diesel dino oil, to diesel synthetic oil.  The reason is that the synthetic will last from 10,000-20,000 miles between changes!  I plan on using oil analysis to monitor the condition of the oil, so that I will know when it needs to be changed -- guessing by the mileage ends up wasting a lot of good oil.  I expect to get more than 10,000 miles from it, though, based on other riders' experiences.  YMMV.  Cheers!