Cam chain tensioner confusing

So I’ve been restoring this new to me vf1000f and I have been suspecting something wrong with the cam chain or tensioner or something, bike starts and runs great but as it starts to warm up a rattle develops on the rear cylinders, so the work week is done picked up some beers and spent started the investigation. Tons of slack on chain between the 2 cams so I took out the tensioner , the sliders are good but the tensioner mechanism seems really tight or hard to make move, the lever the rod slides through ( sorry not sure of the name of this lever) seems to work or at least move but doesn’t seem to lock on to the rod when I can move it a bit. So anyway this whole thing has got me confused how the tensioner is actually suppose to work? Is the spring suppose to keep constant pressure or is the spring for locking the “ lever “ into place? What forces the tensioner to tension onto the chain? As the tensioner is now the spring is in its most relax state. When the bottom of the tensioner is in the foot or base in the motor does this create tension( did I just talk myself into an answer? Still not sure) can any one enlighten me how this works, or what the problem maybe. Thanks have a good weekend. Cheers.

Hi Flash,first off congrats on your VF.
The tension on the chain is provided by the spring pulling the arm of the tensioner down and bowing the blade which is fixed at the bottom end near the crank.
The spring also maintains pressure on the locking rod securing it in the lock plate(works like the mechanism on a silicone gun)
This mechanism is self adjusting under normal circumstances but can be reset manually.
Turn the engine forward until there is tension on the front run of the chain and there is no slack between the cam sprockets.
Now all the slack is on the tensioner side.
The tensioner can now be pulled up with a pair of grips as the lock plate is pushed forward with a screwdriver.
Release the lock plate and then the grips
The tensioner should now be locked in the correct position.

Thanks for that info, from looking at the tensioner the locking plate does not hold the rod,the hole in the locking plate looks worn oval slightly. I’m thinking the cam chain has stretched because the tensioner was not locking or visversa but I can find no specs on the cam chain how to check like distance between x amount of links. I also cannot find an open chain with master rivet link in Canada or North American, I can only find one in Australia but not sure of the quality of that chain. The chain in the bike now is did 219 fts, I’m assuming original and has approx 60000kms which seem premature to need replacing.

Here some info about chains that I believe will be relavent for cam chains such as the 219 , I was suspecting my chain was stretched but after measuring out 12 links I was bang on with the 7.774mm between links ( pitch) I think the only problem is the locking plate hole has worm oval and doesn’t lock
https://cutpriceracing.com.au/store/Page17/

Thats quite possible, sometimes the lock plate creates a groove in the pin, the mechanism struggles to pass over it and slips back…

some of the early models had problems with cam chain tensioners not holding so Honda brought out a modified one to fix the problem. not sure what the modification involved. I would try smoothing off the rod to get rid of any grooves or marks. you could also bend the plate up or down a little at a time to make it stick and manually check to see if it helps. if that doesn’t work then try bending the pin a little to an angle where it will stick. I know it is drastic advice but if you can’t get another then you might want to try it. Whatever you do, do not heat up to bend because the material is probably spring steel.

Thanks for the advice, it does seem a bit drastic bending parts but without many parts available we will have to share ideas and fixes that work. The spare tensioner I have seems to be working better but the real test will be when this snow is gone and I can get out on the road.

If you have look over some of the past posts You will find this covered with photos too. I had the sam problem with mine and after stripping and replacing the chains i discovered the problem was caused by the plastic sheath on the locking plate spring actually holding the locking plate and not allowing it to lock the rod. Remove the plastic sheath and the problem goes away.

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You know what that could be main problem, between the 2 tensioners the original plastic was all bunched up, the two had similar small marks on the rod but the the replacement works awesome and the plastic was good on it, it never entered my mind that could be the problem. I should have removed the plastic totally, at least it will be something to look at if the problem comes back. Thanks.

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Not sure if this picture I added works? But want to show off a bit. lol.

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Nice!
Keep up the good work!