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Location: Auckland NZ
Car type: 36 Nippy, 31 RM, 38 Special, 24 Works Rep
My friend Neil Beken is rebuilding a three speed box and is considering ramping the dogs to improve the speed of change up into top. I have not personally carried out this modification has anyone got experience of positives or pitfalls? And can anyone provide photos showing how deep and the angle of the relief
Black Art Enthusiast
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Location: Scottish Borders
I have the 'Andes' 2nd gear wheels supplied by Andy Bird. He ramps the dog for engaging top on the 2nd gear wheel. It works well. Engaging top gear is much easier and it can just be pushed straight in if necessary. Very useful when hill climbing, it avoids the embarrassing situation of losing so much speed in the gearchange that I have to go straight back down into 2nd. I also have a lightened flywheel which helps too.
Jim
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26-02-2020, 08:24 PM
(This post was last modified: 26-02-2020, 08:25 PM by Ian Williams.)
Thanks Jim, I understand the logic and think I know the best way to ramp the dog, BUT my thoughts are not based on experience so I was hoping someone would have some pictures/dimensions of previously successful ramping. I feel that even a comparatively shallow ramp at quite a shallow angle on the face of dog would help considerably.
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Do the "Andes" 2nd gears require a corresponding ramp on the 1st motion shaft dog?
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26-02-2020, 11:19 PM
(This post was last modified: 26-02-2020, 11:23 PM by Joss.)
Thanks that picture confirms my thinking we shall proceed down that route
PS I have just realized that as I am over with Joss and on his laptop it comes up as if he has responded, so to clarify this is Ian thanking you for your responses
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Location: Scottish Borders
Just ramping the one side seems to work fine.
Jim
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Location: Auckland NZ
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Jim, I feel ramping both sides would be a mistake, the ramp would need to be on the side of the dog not normally loaded, if you ramp both sides of the same gear you defeat the object of catching the corresponding gear. If you ramp the ist motion shaft and the 2nd gear, or cut the ramp too deeply you run the risk of it jumping out of gear on the over run.
Thanks again for everyones input.
Black Art Enthusiast