Cam chain tensioner week!

[Stormer Dave]

Final note tonight chain had come away but I may have got away with it.

I've one last query before the hammer comes out - thanks for all of the guidance and support so far!

With my mates pressure tester (owns a garage) i've plugged my compressor and chucked 200 psi through the sparky hole with the timing set on the cams as it should be and get no hiss from the valve areas...so I tested by rotating a small bit to see what the hiss might sound like with a bit of valve open sounds - definitely hissed it's bag off. Put the timing alignment back as it should be if as per Sirch epic process and no hiss other than that going down past the pistons.

However, I have also tried the method Tony suggested on the valve clearances, and they are tight.................I may be learning again here as it is a bit awkward to get the feelers in................I also have borrowed his bent feelers ( he mentioned this happened on 185 single piston hondas in the 80's (lol as I was whining my bag off - yes you guys reply we know).

So whats the deal, if the clearances were real slack then I'd think I would have done the valves...... but no hiss....and could I be measuring wrong what do ya think?

Anyone up for a garage day in Wales.....

Dave

[Stormer Dave]

I used the notes from the link it was great and well written..........

Gents if I knew how to get photos on here you see the various stages of progress...hard to check valve clearances when the frames in the way though..........

Unless anyone knows some top tips that don't involve an angle grinder and Tig welder (although various forms of vehicle violence have crossed my mind during the last two days...

Choices manual ccts and risk it, valves don't seem to be leaking....or rip the head off and check em anyway...............

What would you do.....how tight do these manual CCTs go in anyway?

Dave

[benny hedges]

What would you do.....how tight do these manual CCTs go in anyway?

Dave

if you mean the tension on the chain, surprisingly slack,
you should be able to move the chain up & down with about 10mm deflection.
you will know when you start it up - either it will rattle a bit if theyre too slack or it will sort of squeak a bit if its too tight. (when you press the starter)
if it squeaks back it off a turn and start it up again. try it again with the engine hot.

dont forget to put threadlock on the long bolt to seal any oil seepage and stop the bolt backing off.
the locknuts need to be F'in Tight... dont just rely on the o ring if you have APE type tensioners.

[tony.mon]

If you have good compression then your valves are fine.
So re-time the cams accurately and change to whatever tensioners you want, then reshim to tolerance.
Sounds like you got away with it, lucky bugger!

If you're having trouble getting to the front head clearances I find it's quicker to pull the carbs off their seats, then remove the plastic shield underneath.
Then they're easy to get to.

[sirch345]

Dave, It sounds like you got away without bending the valves I agree, and yes cranked feeler gauges are much easier to use for measuring the valve clearances.

As for the manual tensioners you need 6mm to 10mm deflection (up and down movement) of the cam chain between the cam sprockets. To do that you'll need to remove the cam chain guide first. Make sure you bung up the cam chain tunnel with a clean cloth before removing the side bolt on the cam chain guide. You don't want to drop the bolt down into the engine.

Chris.

[AMCQ46]

Sounds like you were lucky.

I agree with the others, if you have compression, and that fact the clearances are tight rather than slack, says its all good. Get new tensioners of your own choice [even stock honda are a good option as long as you do the fail safe stopper mod], do the clearances, front & rear. and you are back on the road and you now know your bike inside out.

While you have the carbs off, you can also fit a vacumn take off adaptor to the front cyl [there is a small blanking screw just under the intake rubber, and it is a b8stard to get to with the carbs still on.] and then you can balance the carbs as you rebuild.

[Stormer Dave]

Thanks folks for all the encouragement.

I have the carbs off they came off last night, in fact I was ready to get the head so you can imagine there is not much in place other than the frame, engine and cams....

Didn't get the bit about the cam chain though soz....I have already removed the metal piece that sits using 3 bolts on top of cam pullys so if that is (sirch) where you mean I need to check the tension (6mm - 10mm) then I guess I'm ready to go. I also have some CCT manual tensioners now...

Going to have another go checking actual valve clearances then I'm going to record what they are try to work out what the shims would be.......

Again thanks to all of you...we must get a ride out somewhere sometime........as I owe you all a beer, coffee or whatever your choice is....

I have to say lads and lasses regardless of the crap (and being a designer I could probably work out a long term fix for this) design tensioner ( it has to be simply because the worm spring gets tired due lack of oil) this forum and you folks in particular are ace.....

Moral support is also as good as technical support at the point when you think 4lbs lump hammer is the only way forward........

I will get some pics on at some point...since I've now read up on how to do it.

Dave

[Jazzscot]

good work Dave mate Im glad your making progress. This is a great forum with loads of knowledgeable folks. I managed to bring mine back from the dead last year.

Let us know how you get on.

Jazz

[sirch345]

Didn't get the bit about the cam chain though soz....I have already removed the metal piece that sits using 3 bolts on top of cam pullys so if that is (sirch) where you mean I need to check the tension (6mm - 10mm) then I guess I'm ready to go. I also have some CCT manual tensioners now...


Dave

Dave, yes "the metal piece that sits using 3 bolts on top of cam pullys" is a guide, if you look underneath it you'll see some white-ish hard plastic there. You need to measure the deflection of the cam chain between the two cam sprockets (pulleys), which you cannot do with that guide in place. I hope that's a little easier to understand

With your manual adjuster fitted (all timing marks already lined up of course for that cylinder at TDC and cam lobes facing in the right direction for that cylinder) turn it in or out until you have between 6mm and 10mm of deflection of the cam chain between the two cam sprockets. You can then lock the adjuster off in that position. A finer adjustment can be made later if needed once the engine has warmed up.

Chris.

[Stormer Dave]

Sorted bike is back together less fairing - got it back put to today down the road and all appears to be very very well..................

Thanks to everyone.....

Dave

[sirch345]

Good news, well done Dave I bet you gave a sigh of relief when you pressed the starter button and she fired into life

Chris.

[Stormer Dave]

Good news, well done Dave I bet you gave a sigh of relief when you pressed the starter button and she fired into life

Chris.

Yeah you bet.................hammers gone back to it's rightful place in the shed............

Wife said it's smoking a bit, I laughed as that was one of my tests with the cam timings set I placed a little bit of engine oil down the valves.....engine kicked in first time without the air box or tank....ran sweet and then spluttered a few minutes later when it ran out of fuel....managed to check the carb balance, put a take off pipe on the number cylinder.................

So yeah, no rattles, no adverse bangs (other than the ones we like to hear) - went up the road ace, felt quite different actually without the fairing on..........banged it up to 8K then backed off, in 1st, 2nd and 3rd........no problem...

Settings on the valves were .31 front ex, .30 back ex, .157 both inlet.................

This is the best forum..........