Kick Starting

Hi Roger - The factory delivered compression ratio of a 650SS was 8.9:1 whereas the Atlas was 7.5:1. I doubt very much that you would notice any such difference using the kickstart.  Many Atlas bikes had Commando pistons fitted by the owners, at rebore intervals, because the original Norton or Hepolite items became very rare.  The factory delivered compression ratio on a 750cc Commando was 8.9:1,  by the way and so as time went by most Atlas bikes were the same as the 650SS. You could try using an extended kickstart lever from a Commando on your SS as that may help.  Good luck, Howard    

Strangely i find that although the Atlas with its Commando pistons is hard to get moving from cold .once its on the move the heavy flywheel keeps it ticking over even if one cylinder is a bit reluctant. . Cant make much of a comparison with the SS as up to now I have not managed to fire it up as its very stiff . A shift to 20/50 oil may help.

Hi all, 3 weeks ago I bought an Atlas off a mate of mine who cannot kick start it because of his knees. I could start it but sometimes had to stand on the kickstart (and bounce on it) to get it just over the compression. However, it was hard work and sometimes just couldn't seem to get enough leverage on it. We were talking to another mate with a Commando when we noticed the kickstart on the Commando which seemed longer and had a crank. We borrowed it and tried it and I am pleased to say that I no longer have to stand and put all of my weight on the kickstart. I have added some images and dimensions of both the Atlas and Commando kickstart levers. I hope this helps. I also wondering if the 1" crank is helping as well which would give 2.5" additional leverage over the Atlas kickstart.

I've seen Nortons with modern "fold-out" style kickstarters fitted. RGM among others produce these. I've just looked on their website, there is a handy little chart of various Norton levers and their dimensions*. Their foldout version , based it says on the T160 Trident is listed as 8.5" centres, although apparently not currently available due to a tooling shortage. *Link here: https://s3-eu-west-1.amazonaws.com/rgmnorton/fs/pdf/kickstartdimensionspdf.pdf

Some owners grind away the splines inside the lever for 1/2" or more each side of the split. This allows the edges of the split to come closer together, and the kick-start doesn't rock and grips better on the remaining splines. And of course make sure the split still a small gap...