Author Topic: Why do we adjust camchain tension  (Read 426 times)

Offline marroinia

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Why do we adjust camchain tension
« on: February 15, 2020, 12:14:43 PM »
Hi there!

I'm preparing myself to open my engine head cover and put the missing dampeners back in where they are supposed to be, at the ends of the tensioner bow. As i'm thinking about the damages it could lead to if riding to long without them, I struggle to understand why do we have to slacken the bolt to adjust the tension:

A/  As the camchain wears loose, the bow isn't pushing anymore because the pushrod is kept in place by the tensioner bolt?

B/ As I'm riding hard, the cam chain push against the bow that is forcing back the pushrod that stays here, kept in place by the tensioner bolt?

C/ Both?

D/ You can't understand my french gibberish!

help me please,
Cheers!

Offline Nurse Julie

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Re: Why do we adjust camchain tension
« Reply #1 on: February 15, 2020, 12:21:02 PM »
A. It is a self tensioning system. You just undo the bolt to allow the tensionsioner to reposition itself depending on the wear of the chain.
« Last Edit: February 15, 2020, 12:23:26 PM by Nurse Julie »
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Offline marroinia

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Re: Why do we adjust camchain tension
« Reply #2 on: February 15, 2020, 01:16:27 PM »
Ok, thank you to make it clear, Julie!

My bike is 25000km old, around 16000 miles, the camchain should be ok for another 20000km, what do you think?
And if the bottom dampener is missing do you think I can stick it or attach it with a very thin copper wire or fishing line to the tensioner bow an drive it carefully in the horseshoe by the top of the engine?

Offline Nurse Julie

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Re: Why do we adjust camchain tension
« Reply #3 on: February 15, 2020, 01:31:20 PM »
Ok, thank you to make it clear, Julie!

My bike is 25000km old, around 16000 miles, the camchain should be ok for another 20000km, what do you think?
And if the bottom dampener is missing do you think I can stick it or attach it with a very thin copper wire or fishing line to the tensioner bow an drive it carefully in the horseshoe by the top of the engine?
Can't comment on the cam chain as even though it's only done 16000 miles, who knows if the bike was ridden sensibly and had regular maintainace or has been thrashed everywhere. You always take a risk when trying to fit something down in the engine, it could fall off of the wire and get jammed down in the crank case somewhere. Why do you not have dampers fitted?.
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Offline marroinia

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Re: Why do we adjust camchain tension
« Reply #4 on: February 15, 2020, 03:18:12 PM »
Well, I checked the chain last time I tried to unlock the horseshoe, it wasn't possible to lift it out of the cam sprocket even with the tensioner fully loosen.  I unlocked the horseshoe quiet easily, now its moving free and the whole thing seems to be under proper tension... So i guess the bike have been rode without servicing but not long enough to do major damage to the pivot.

The previous owner rode only a few hundred kms out of Paris with that 400. He told me the head gasket have been changed while valve gasket or guide (?) have been replaced, the bike was smoky and capricious.
The job have been done by a friend of him, a "professionnal". I'm pretty sure he forgot tu fit the dampers back when mounting the head, I'm also pretty sure that no serious professional was in the place as the whole bike was a mess of approximatively done job. Nothing broken, just a bike left to unaware people.

I've never seen smoke and she running great at first or second kick since I tuned her properly.

I figured out the missing parts after I put back everything together! :( Looking at cmsnl drawings, I saw the damper and I understand there is no damper in my bike, at least the top one!
« Last Edit: February 15, 2020, 03:24:19 PM by marroinia »

Offline mattsz

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Re: Why do we adjust camchain tension
« Reply #5 on: February 15, 2020, 03:27:02 PM »
I'll be naming my next CD "Smoky and Capricious"...

Offline marroinia

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Re: Why do we adjust camchain tension
« Reply #6 on: February 15, 2020, 03:38:12 PM »
I'll be naming my next CD "Smoky and Capricious"...


 ::)
Does it sound strange in english?

Offline orcadian

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Re: Why do we adjust camchain tension
« Reply #7 on: February 15, 2020, 04:01:43 PM »
As Julie says,
I wouldn’t wire the damper in case it falls off and I can’t think that there is enough clearance in the ‘bucket’ on the horseshoe for anything other than the damper block.  New dampers are a good fit on the eye of the blade anyway.  I think I would stick the damper to the lower end of the blade after removing any traces of oil, with something like ‘sticks like sh!t’ adhesive (hope it’s available in France!) and leave it to dry overnight before fitting.  I don’t think a THIN smear of adhesive will prevent the small amount of angular movement needed and it will probably eventually let go when oily and hot.
How did you free up the horseshoe?  Might be something we all need to know.

Ian

Offline Nurse Julie

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Re: Why do we adjust camchain tension
« Reply #8 on: February 15, 2020, 04:02:56 PM »
I'll be naming my next CD "Smoky and Capricious"...


 ::)
Does it sound strange in english?
Sounds the perfect word to me 👍👍👍
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Offline marroinia

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Re: Why do we adjust camchain tension
« Reply #9 on: February 15, 2020, 04:35:39 PM »
I think I would stick the damper to the lower end of the blade after removing any traces of oil, with something like ‘sticks like sh!t’ adhesive (hope it’s available in France!) and leave it to dry overnight before fitting.

I got something like that in the tool box, it even sticks plastic on car paint, I will try that if the lower one is actually missing,

To free the horseshoe I did a bit like I read on this forum:  a screwdriver in the pushroad hole in front of the engine just to feel the movement, and I pushed directly on the blade with my thumb. At first the blade was coming back with no response in the screwdriver so I pushed hard on that one, and the blade answered. Then I worked one to another, it took no long to make it work properly.

Offline SteveD CB500K0

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Re: Why do we adjust camchain tension
« Reply #10 on: February 15, 2020, 04:39:25 PM »
Capricious is a great word for our old bikes.

As long as they are female of course.

If your bike is male (mine is) then it’s either a “good old boy” or a “bastard”




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Offline K2-K6

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Re: Why do we adjust camchain tension
« Reply #11 on: February 15, 2020, 05:14:36 PM »
Would the glue be, Bâtons comme de la merde?

French language even makes that sound good over here  ;D

Offline hairygit

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Re: Why do we adjust camchain tension
« Reply #12 on: February 15, 2020, 05:21:02 PM »
Capricious is a great word for our old bikes.

As long as they are female of course.

If your bike is male (mine is) then it’s either a “good old boy” or a “bastard”




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Thought everyone of our generation called them "she"
After all, they consume all your time, all your money, and still give you sh#i/ let you down when you really don't need it!

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If it's got tits or wheels, it's hassle, if it's got both, RUN!!!

Offline marroinia

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Re: Why do we adjust camchain tension
« Reply #13 on: February 15, 2020, 06:04:03 PM »
Mine is a she as in french "moto" is a female noun you cant say "le moto", only "la moto". Hairygit I have another "she" at home that is often hanging up the rpm  , i might not be rich enough  ;D

Would the glue be, Bâtons comme de la merde?

French language even makes that sound good over here  ;D

Colle comme la merde  ::) it's a bit meaningless

Offline orcadian

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Re: Why do we adjust camchain tension
« Reply #14 on: February 15, 2020, 06:18:57 PM »
Would the glue be, Bâtons comme de la merde?

French language even makes that sound good over here  ;D

Coming from Yorkshire I don’t understand the language - were they French letters you used?

I’ll get me coat!

Ian

 

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