timing marks

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Bison
Posts: 157
Joined: 27 Mar 2013 10:49
Location: West Lothian

timing marks

Post by Bison »

Hello folks,
Am I correct in assuming that at TDC on the firing stroke, both valves slack, the dot on the camshaft gear should align at 12 o'clock with the mark on the casing as it shows in the manual?. Mine is at 6 o'clock?. Crank dots are aligned as per manual. Bike runs fine, starts fine, ticks over, revs. It's an L5 cam seemingly.
Alan.
EVguru
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Location: Luton
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Re: timing marks

Post by EVguru »

Rotate the crankshaft by 360 degrees.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
Bison
Posts: 157
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: timing marks

Post by Bison »

As I said, am I correct in thinking the timing mark for the cam gear at TDC Compression stroke is at 180 from where it's shown in the manual, at the top ?. It would be on TDC Exhaust stroke if I turn the crank 360, is it timed on the exhaust TDC?
Alan.
EVguru
Posts: 1530
Joined: 01 Aug 2006 11:13
Location: Luton
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Re: timing marks

Post by EVguru »

Sorry, answering the wrong question.

The TDC marks are on the flywheel. Where they line up depends on whether it's an early or electric start engine. It's in the manual.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
Bison
Posts: 157
Joined: 27 Mar 2013 10:49
Location: West Lothian

Re: timing marks

Post by Bison »

Gents,
Found my answer in the search engine. Sorry to waste your time again. Here it is.


Many apologies for taking so much of your time! I followed the instructions in the manual for setting valve timing: I first brought the front piston to TDC and also set valve clearance to 1.0mm. I then turned the camshaft pulley clockwise until the 1.0mm clearance on the inlet valve was taken up (I could not twist the inlet pushrod anymore). With the inlet cam/rocker now just about to open the inlet valve, I turned the crank clockwise (not to the left as incorrectly translated in the manual) until the inlet open mark I had scribed on the rotor (28deg for my Sport or approx. 8mm to the left of the ANT1 mark) aligned with the notch. Now, the camshaft is about to open the inlet valve and the crankshaft is 28deg BTDC just finishing the exhaust stroke. When I then turn the crank the 28deg needed to get the crank/piston to TDC, the mark on the bottom crankshaft pulley and the punch mark on the bearing boss and the keyway on the mainshaft all align at 2 o'clock. The dot on the camshaft pulley now also aligns on top with the notch on the case. The camshaft pulley keyway is now at the bottom 180deg opposite the notch. This is TDC on the intake stroke and all the the dots/keyways align as shown in the various videos and in the manual. My only question is rather than it being the start of the firing stroke, it looks like this is the start of the intake stroke. Is this right? The manual keeps talking about setting the front piston to TDC on the compression stroke which does not seem correct. This is a link to my Morini restoration project - the last three photos show what I am talking about.

https://picasaweb.google.com/1169829683 ... MotoMorini

Joe

ps: I am updating my post above after having set it the way I describe above and found that the engine runs fine.The manual is incorrect when it states that it should be at TDC of the compression stroke - the only time the cam pulley and case notch align and the crank pulley, crankshaft keyway and punch mark on the bottom bearing boss ALL align is when the piston is at TDC on the intake and NOT compression stroke. End of saga!
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