650ss Timing

Thanks. I know i paid a bomb but NOC records it as a paul dunstall delivered and the magazine states it may be the only one known to be left. Isnide the cases are like new but it appears the last owner has messed it up. Found super lean settings on needles, lean main jets, timing set to 11 rollers instead of 10 and the points only opening to 6 thou. No wonder it ran like a dog. I rode my first Dommie to Bathurst from Wagga with my girlfriend on tbe back. Sometime in the early 80's.
Loved that model 88.
 
Not particularly relevant, as most of my posts tend to be, but I ran a 2S in a 750 Norton engine with 9 rollers between the dots. Not sure if that was intentional or a hurry up mistake during a at the time significant engine modification. I didn't discover I set it up like that for 29 years. I was lucky I didn't have issues with the valves (possibly). Bike ran really well, although it was a little hard to start and idled like it had a big cam in it until I installed a TriSpark ignition last year which cleaned up the idle some and made it a little easier to start. Could have been 50 other reasons why it was hard to start though. Ignition timing was never spot on. Hard to strobe a P11.

Probably hard to strobe a 650SS as well. Although I've never owned one so no clue.

I have a K2F and all the gear to use it, but wouldn't install it again ever. Not a fan of working with that primitive multichain work inside and outside the timing chest to set up ignition timing at all. Took a look at it all yesterday, since this thread piqued my interest a little. The grease in the AAU is hardened up so much the weights won't move. Need to put a heat gun on it. It's 30 degrees in my garage this time of year. I can't see the threads at all for backing off the AAU. If the reverse threads are there they are hidden behind the weights and don't engage with anything when I turn the bolt head counter clockwise. I don't remember how I got it off. Right hand threads on I can see behind the taper. Only way it would not thread onto the magneto shaft is if the threads on it or the K2F were stripped as Slick mentioned.

For anyone reading this I'm not looking for advice on how to do anything with the K2F or stuck AAU. It is perfect in the box it is in. I'm just passing along an observation.
 
Magnetos are often good until they get hot. But a battery can be a nuisance. The cam in my Commando is probably the same as in a 650 SS. From it's timings, it is as hot as an E3134 Triumph race cam. If it is advanced, you get more torque, but the exhaust noise becomes louder.
 
Hi
Have you got a good spark out of the magneto, if not already done clean the oxidation layer off the points if the bike has been sitting for any length of time.
Burgs
 
Thanks everybody. Seem to have a good white spark. Will re time the bike and let everyone know. I love the feedback. Cheers from WaggaWagga
 
hello now after reading you dreamers on timing there was nothing said about witch side your timing the engine from the factory manual says you start of with the drive side being the left hand side and removing all rocker covers so you can then see the valves are both in the closed position on the left hand side and at TDC now fit your timing disc and pointer at zero now turn back the engine to 32% now all 650s but the de-lux and standards were fitted with Lucas k2fc magnetos the 650 de-lux and 650 standard were fitted with Lucas distributor and rm 15 alternators with emergency starting coils and SA88 lighting and ignition switch the very early 650s had the SA 41 lighting switch and RM 19 alternator witch the timing disc is fitted and point fitted to the rear cylinder stud pointing at zero and left hand set of valves closed at TDC then turn back to degrees and jam open the bob weights for full advanced now set the point on the mag so the point are looking up ward and the cam eel is near the bottom of the cam ring this is for the rear plug lead on the mag witch is for the left hand cylinder the nearness plug lead to the barrel is for the right cylinder now points set at 12 thou fully open now take it back so the point are just in breaking position with your timing light flicking now do up the ADT bolt and hold the other side with a 3BA spanner the check the timing by turning the engine forward and the point should be full open at 6% after TDC now the timing is set refit all parts and go for a test ride
 
Obviously I cannot coment on the engine timing, other than it sounds like someone was trying to either advance or retard the camshaft.
I would simply mound a degree timing disc on the crankshaft and return everything to the standard setup, including checking the ingition timing is 0 and 180 degrees dead.
You will find the engine runs a lot sweeter as Norton intended.
 
Any 4 stroke gasoline engine can be timed by the crossover point on the inlet and exhaust valves. Make that point happen at 4 to 6 degrees BTDC and you will have a sweet running engine, lawnmower, rototiller or race bike.
I timed my 920 by the book method, 10 rollers, also as described by Mick Hemmings in his video.
For interests sake I checked the crossover point and it was smack on 4 degrees for one cylinder and about 5 degrees for the other.
For my 1360 Vin motor I didn't have any timing marks so I just used the crossover at 4 degree btdc method then made my own marks for future use.

Glen

650ss Timing
 
When you advance or retard the cam, you usually change the pwer band's position, and the exhaust system does similar. The two need to work together. A more restrictive exhaust system can work better if the exhaust valve opens earlier. However there is a balance between fuel octane ratio, ignition advance, compression ratio and jetting which must also be optimised. While you are trying to achieve that, heat build-up can become a problem - particularly with petrol.
Normally, if you keep all other things constant, you can achieve a lot just by jetting carefully. Many motors are probably all over the place, but are corrected through carburettor adjustment.
 
hillbone said:
So in checking the timing etc Ive found the points would only allow 6 to 8 thou in the gap so I machined the adjusting slot larger to allow the correct 12 to 15 thou.
Your thoughts please.
Cheers Hillbone.
Click to expand...
Just a comment on magneto timing. Likely you have a worn fibre part on the breaker. Due to no lubrication on the magneto cam. By machining a wider slot, the internal timing in the magneto changes so that magnetic field collapse isn't when points open. Resulting in a weaker spark. Might be part of your problem.
Though cam timing is the obvious thing to fix.
 
I gave up on K2F magnetos because new points sets are such poor quality.

Did you work out how to use the slightly mad left hand extractor thread on the auto advance pinion? You unscrew the nut (that looks like a bolt) from the magneto armature and keep turning until it pushes the ATD off the taper. The coarse left hand thread does not engage, because it’s being turned the wrong way for engagement. It just pushes.
 

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