I recently fitted a new G83 kickstart shaft because the original one was twisted and slightly bent and was only discovered when I was replacing the G47 and G46AS kickstart ratchet and pinion. I retained my G82 quadrant as it was in perfect condition.
I refitted the cover having fitted the new parts from the Vincent Spares Company and a few days later decided to give the bike a run. I turned it over a few times on the decompresser and then readied it for a good swing. BANG! the kickstart went with a sickening crunch. I quickly ripped off the cover to find the Quadrant in two parts, having broken at the internal splines. Closer inspection showed the G83 shaft splines were crumbling.
I still had the original shaft and brought both shafts to get a hardness test done as the old one resisted marking with a file and the new one was like butter to the file test.
The old one measures 22.5 HR"C" and 67.5 HR"A". in other words it had a very good hardcase.
The new one measures 27 HR"C" and 34 HR"A". In other words it's hardcase was just a joke.
Do any of you metallurgists have a more suitable steel and heat treatment in mind for this job.
I have been told that the supplier is using Material – EN24W (817M40) Heat treat to ‘W’ condition 1080-1240 N/mm[SUP]2[/SUP] (70-80 Tons/in[SUP]2[/SUP])
I refitted the cover having fitted the new parts from the Vincent Spares Company and a few days later decided to give the bike a run. I turned it over a few times on the decompresser and then readied it for a good swing. BANG! the kickstart went with a sickening crunch. I quickly ripped off the cover to find the Quadrant in two parts, having broken at the internal splines. Closer inspection showed the G83 shaft splines were crumbling.
I still had the original shaft and brought both shafts to get a hardness test done as the old one resisted marking with a file and the new one was like butter to the file test.
The old one measures 22.5 HR"C" and 67.5 HR"A". in other words it had a very good hardcase.
The new one measures 27 HR"C" and 34 HR"A". In other words it's hardcase was just a joke.
Do any of you metallurgists have a more suitable steel and heat treatment in mind for this job.
I have been told that the supplier is using Material – EN24W (817M40) Heat treat to ‘W’ condition 1080-1240 N/mm[SUP]2[/SUP] (70-80 Tons/in[SUP]2[/SUP])
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