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Messages - Caulky

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Twins / Re: '71 A65L valve timing
« on: 17 May, 2018, 20:08:41 »
The engine is in the frame.
I'm on the Isle of Wight.

Twins / Re: '71 A65L valve timing
« on: 17 May, 2018, 18:05:39 »
Hi again
After changing to the drive-side inlet valve only, and by advancing the cam-wheel by one tooth, the opening time on the degree wheel was reasonable.
So, fit the other inlet valve...but check the closing time first.
Same trouble, too early! 45 degrees after ABDC.
It makes me think I have the wrong camshaft fitted?
The other problems are mounting the clock and setting the tappet gap.
To eliminate the gap trouble, I clocked the adjuster screw to .015", by lifting/dropping the rocker arm.
The clock is reasonably steady, but as the rocker-arm moves, so does the angle.
As far as I can tell, the lobe centre is good.
I'm not happy with this, but what to do? Getting hacked-off with this.
Even if the inlet side is OK, the exhaust is likely to be wrong.

Twins / Re: Misfire
« on: 16 May, 2018, 10:17:43 »
You could try a larger main jet, or smaller?
A plug chop after it happens could give you a clue.

Twins / Re: A65 Lightning
« on: 15 May, 2018, 09:58:47 »
It would help if you post a picture and some details, year, matching numbers?, is it running?, etc.
Then someone may have guess of the value.
Have you looked on Ebay at similar models?

Twins / '71 A65L valve timing
« on: 21 April, 2018, 15:39:10 »
Sorry to bring this up, again.
Now, have I got this right?
I have read all that I could find on this subject, but some things are still confusing.
When doing this job, some say the 'clock' should be on the valve collar or on the rocker arm adjuster.
Others say, this is incorrect because the quoted figures are for the pushrods/tappet followers.

Another thing is, people talk about 'lift', do it at .040".
Lift meaning valve lash? It could mean, turn the crank + .040" @ 0.015" lash, after the needle begins to move and read the degree-wheel?
Also, taking the WSM figures for inlet: open 51* BTDC, close 68* ABDC at 0.015" lash.
Using these figures, we have 51+180+68 = 299*. 299/2 = 149.5*.
The cam lobe centre is given as 98.5* crank ATDC, so for the cam centre we subtract 51* from 149.5* = 98.5, OK fine. (this MAY be the lobe peak, but not neccessarily).
But, the quietening cam ramp needs to be avoided, so the measurements need to taken at .040" lash, not at 0.015"
OK so far?

Twins / Re: A65 Gearbox Camplate
« on: 17 April, 2018, 10:55:57 »
My '71 spares book shows 57-4026 for all variants.

Twins / Re: Tight Valve rocker spindles
« on: 08 April, 2018, 09:55:09 »
It is not an easy job and requires patience.
You should be able to slightly withdraw the spindle, without disturbing the other washers.
If you look through the assembly, from the other side using a flashlight, you can see which washer/spring is out of alignment.
I use a small paint-brush handle to align the holes.
Do not force it!

Twins / Re: '71 A65L valve timing
« on: 06 April, 2018, 10:00:35 »
There is no problem with the R/H inlet valve, except the timing is too early.
This is why I am going to try both inlet valves fitted.
I suppose it could be valve to valve clash, with all valves fitted, rather than valve to piston.

Twins / Re: '71 A65L valve timing
« on: 05 April, 2018, 19:08:21 »
Thanks chaps.
I think firstly I'll put both inlet valves in, to see if it still locks-up.
Which was the original problem.
As you say, things could be out, just using one valve fitted.
Alternatively, I could try clocking from just from the pushrods. (inaccurate I know).
I used the R/H inlet valve because the clock faces the wrong way on the left side, frame in the way, and its a long type.
Its bad enough trying to get the clock rigid as it is.

Twins / Re: '71 A65L valve timing
« on: 05 April, 2018, 17:55:38 »
Sorry about the time lapse, can only work when the weather is reasonable.
The data I have is from the book, at .015" gap, inlet opens 51* BTDC, closes 68* ABDC.
I presume the mid-lobe is not half-way between these two points...uneven ramps?
Now, SRM give at .020" gap, inlet opens 45* BTDC, closes 78* ABDC, duration 303*.
Some time ago Mr Pete of Australia RIP, stated set the gap to .040" to avoid the inaccuracies of the lead-in ramp.
Inlet opens 28* BTDC, closes 47* ABDC, Lobe centre 99.5 ATDC.

Results for mine, @ .020" gap, opens 63* BTDC.
At .040" gap, opens 45* BTDC, closes 34* ABDC, mid lobe 92* ATDC.
Far too early.
So, is the mid-lobe 99.5*?
If I set the mid-lobe at the correct point on the crankshaft, remove the jocky-wheel, then rotate the camshaft wheel to suit, then re-insert the jocky-wheel, is this a good move?

Twins / Re: '71 A65L valve timing
« on: 26 March, 2018, 20:23:36 »
Thank you, I will check it out and get back to you.

Twins / '71 A65L valve timing
« on: 26 March, 2018, 17:21:45 »
Hi All
Before the winter break and fitting the pushrods. rocker gear, etc, turning the engine using a spanner on the rotor nut, it jammed BTDC.
So, I thought piston hitting the inlet valves.
I set it up with just the right inlet valve, clock and degree-wheel.
Today, I thought, check the timing marks... they are OK, but for the left valve, hence I had to rotate the engine 360* for the R/H side.
I set the gap to .015" as per the book.
The valve should open at 51* BTDC, but mine begins to open 16* before that, but strangely the piston and valve doesn't collide!
So it must be the left?
I should add that everything is new and the head was sent away for an overhaul, new seats, valves, gas-flowed, etc.
Something is wrong, any suggestions would be appreciated.

Twins / Re: Firebird oif Frame repair
« on: 06 March, 2018, 08:36:48 »
These people may help, found their ad. in Real Classic magazine:

Twins / Re: Gaskets and gasket compound
« on: 28 February, 2018, 11:47:11 »
Depends on which model and year?
I use grease on paper gaskets, blue hylomar for metal to metal gaskets and other types of gaskets.
Head gasket...nothing.

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