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Discussion Starter #285
Disaster

After fitting the inlet rocker gear, the pistons are hitting the valves.
Head off I think for investigation.
Could be camshaft lift too high, piston cutaway too shallow or anything else.
If I slacken the adjusters to zero the engine will turnover completely.
Locks with any adjuster level.
Everything is new except for the pushrods and rocker arms.
 

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Discussion Starter #289
When I fitted the engine into the frame it was bear, for lightness.
The last time I lifted a heavy weight, I ended up in hospital for 3 weeks.
Even so, I could have assembled it, I suppose.
 

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Discussion Starter #291
Before removing the head, I think there are a few measurements to check.
According to the book.
At 15* clearance the inlet valve begins to open at 51* BTDC.
So with zero clearance it will open earlier, but how much?

Book quotes 0 to 45 crankshaft degrees and gives the piston displacement.
45* equates to 0.5158" piston displacement and at this point the piston is moving the most distance per degree.
But I need 51*, which is 6* more,
Given that cyclic values are similar for each quadrant, if I subtract 6*, it should be the same as +6*. WRT 45*
So, looking at 39* it gives 0.3950" displacement.
0.5158" + 0.3950 = 0.9100" displacement...this when the cam lobe begins to lift the follower, in theory.
A timing tool into the plughole should be adequate, but given the angle it wont be 100% accurate, but its a start.

A timing disc on the crank should confirm the above, with a clock on the pushrod.
If its way off, the timing pinions will need adjusting. They are on their marks at the moment.
(hopefully it might be at greater than 51* BTDC/ much earlier) which would give a bit of leeway with piston/valve clash.
The top of the lobe (max lift) happens at 78* ATDC, which gives a lobe height/valve lift of 0.385 or ten turns of the tappet adjuster.

If all this fails, it will mean looking at the piston cutaway, valve seat height, rocker arms, etc.
 

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Discussion Starter #292
Well, the previous post is wrong.
At 45* the displacement is .5158" from TDC.
As there are four 45* quadrants in 180*, I thought 4 x .5158 would equal the stroke, but the stroke is 2.9134.
The quadrants between 45* and 135* are obviously different (longer), 180* to 135* should be the same as 0* to 45*.
Maybe I can calculate some of the values.

A preliminary check with the new timing tool in the plug hole revealed the inlet valve is beginning to open far too early, I think?
However I can't find my degree wheel to check, so I'll make another, its difficult to estimate where the piston should be.
 

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Discussion Starter #293
After the silly season break, today I ventured back into the lock-up.
Only the right-hand inlet rocker gear on.
Reset the gap to .015", found TDC and put the degree wheel on the alternator shaft.
Set up the clock onto the tappet adjuster, found it opens at 51*, OK.
Turned the engine to TDC, valve travel 0.135", so this one appears to be alright.
I'll check the mid point later.
Everything is cold, tools, hands, gave up.
 

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Discussion Starter #295
"Hi Caulky,
Any action on this project lately?"

No, winter break.
As I am virtually working outside, in a lock-up with the door open, I decided to only work when the temperature is over 10C and I need sunlight. Getting old now. :geezer
This is very close now.
 

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Discussion Starter #297
Unfortunately, little progress.
I'm still struggling with the valve timing.
I changed the set-up to just the drive-side inlet valve.
By advancing the cam-wheel one tooth, it opens at the correct point, but closing is still too early. (45* ABDC)
I'm wondering if I have the wrong camshaft fitted, even though I ordered the right part number?
Another thing is, if the inlet side has been altered, so has the exhaust because its a single camshaft, unlike my Triumph Bonneville.
Lack of interest is setting in!

I'm wondering if I should clock the pushrod and check the timing by manually turning the cam-wheel?
 

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Discussion Starter #300
I think there is only one keyway.
After playing about with the cam one tooth forward, I re-tried it on the mark.
Now it opens at 51* BTDC, but still closes too soon.
I put this down to using feeler gauges, they need to be bent because of limited access.
Now I clock the the rocker adjuster screw, moving the rocker op and down for 0.015".

As I have had enough, it will be re-assembled, as is.

Now for the bad news, all of the exhaust rocker gear was in an aluminium tray,
which has had water in it somewhen during the winter.
Condensation from the roof.
RUST! New spindle and washers ordered.

As I remember, when all the rocker gear was assembled last year, it locked-up just before TDC.
 

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