Hi All,
I’m brand new to this forum so be gentle with me and be aware that my knowledge and experience with the British marques is still somewhat limited.
Anyway, it’s a bit of a story so if you’re sitting comfortably, I’ll begin.
About a year ago a good friend of mine decided he wanted a nice RGS replica, so without mentioning it to me he went out and paid a considerable amount of money for what can only be described as a very, very poor kit of badly selected parts which came in several large boxes and crates.
The quality of the parts left a lot to be desired and I was a little apprehensive when he asked me to build the engine but I went for it and built the engine using the parts provided and many more purchased on the way.
Anyway, I gave the completed engine back to him a number of months ago and left it with him to fit it into the frame along with all the running gear.
The process of getting it ready for commissioning was slow due to Covid but I finally went to get the engine running last week for the first time. Guess what? It won’t start!☹️
So, here’s a list of things that I’ve done.
1, At the time of rebuilding the engine I totally rebuilt the magneto and I have a healthy spark on both leads. The magneto has manual cable advance.
2, Totally stripped, ultrasonically cleaned and rebuilt the carb with new Amal parts where required.
3, The engine block is a thick base cast iron item which was honed and fitted with new Hepolite piston rings, gaps checked, all good.
4, Cylinder head is aluminium and is fitted with all new BSA valves, lapped in and checked with petrol, all good.
5, The crankcase/bottom end is allegedly a rebuilt unit and does look to be in good shape. It is fitted with the 67-357 spitfire cam.
So, I have good spark timed at full advance of 3/8”, the carb is a fresh rebuild, valve clearances are all set to correct specification and despite all that with hours of kicking, not even a glimmer of a fire.
I’ve exchanged the leads, tried it on easy start and double checked the ignition timing with no joy.
The only thing I can think of now is valve timing.
The engine number is DA10R 12*** and I know it has the 357 cam in it as I’ve seen the number on the end. The timing gears are crank- 22T, cam- 44T and idler- 49T and when I set it all up all the marks were aligned.
I seem to have good compression and good vacuum on the induction stroke but the only thing I can think of is that it’s not quite happening in the right place.
Main questions-
A, Are the valve timing figures for this cam 51, 68, 78 and 37?
B, If I fit my degree wheel to this motor and set the valve clearances to 0.0020”, do the timing figures relate to the valve just starting to open/close or is it when they are fully opened or closed?
C, Are there any different combinations of timing gears as the ones that are fitted to the engine could be the wrong ones as they were loose in a bag.
D, Am I missing something obvious? Is my lack of experience with British iron shining through?
Another annoying issue he has is that the gearbox, which is stamped with the RRT2 designation provides for the kickstart leaning forward towards the front end dramatically and this makes it very difficult to kick, but that’s another post!
Anyway, I hope you guys aren’t fed up of me already and that you can give me some pointers relating to the above.
Many thanks in advance.👍🏻