So Jim, how about them there timing gears?

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comnoz said:
The idler gear is three pieces with ramps cut in the sides. Ball bearings fit in the ramps and the three gears are pressed together with a wave spring which causes the teeth to be offset and take up the backlash. This is what keeps the gears from rattling at certain speeds and is why this has turned into more of a project than I expected. James
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Clarifying, thanks. Keep up the good work :)
 
Gday Jim, them gears are looking beautiful! Im holding off building my motor to a degree, contemplating those gears? Im not up to speed with the knowledge of gear ramps, is there a good link on the net explaining in more detail the theory? Keep up the excellent work mate, Ive already got your crank vent! Rgds Foxy
 
The ramps I am speaking of are the 4 pockets cut in the side of each gear. They are slots that are deeper on one end than they are at the other. Then when you put a ball in the pockets and lay another gear with pockets on top of it they roll to the deepest part of the pocket. They are positioned so when the balls are at the deepest part of the pocket the gear teeth are out of line with the gear next to it. Spring tension is applied to hold the gears together and the teeth out of line. This keep pressure on the teeth and prevents them from rattling against one another. James
 
Thanks for the good explanation James, so the gears line up under load to spread the tooth wear, Mmmm... very clever!
Rgds Foxy
 
comnoz said:
The ramps I am speaking of are the 4 pockets cut in the side of each gear. They are slots that are deeper on one end than they are at the other. Then when you put a ball in the pockets and lay another gear with pockets on top of it they roll to the deepest part of the pocket. They are positioned so when the balls are at the deepest part of the pocket the gear teeth are out of line with the gear next to it. Spring tension is applied to hold the gears together and the teeth out of line. This keep pressure on the teeth and prevents them from rattling against one another. James
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Would helical gears be quiet? I assume too expensive to produce?
 
Helical gears will cut down on gear whine but the noise problem I have is caused when the pulsing load of the camshaft makes the gear teeth rattle against one another . Only less clearance will solve that. James
 
comnoz said:
Helical gears will cut down on gear whine but the noise problem I have is caused when the pulsing load of the camshaft makes the gear teeth rattle against one another . Only less clearance will solve that. James
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So the gear solution you use is similar to how they handle modern bikes with gear drives or do they use something else?
 
Yes it is pretty common to use a spring loaded segment on timing gears to eliminate rattle. Some bikes use them on the primary drive gears also.
 
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