750 close ratio "3 dog" gears

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cafe*racer
SSD900 Darmah
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750 close ratio "3 dog" gears

Post by cafe*racer » Mon May 10, 2010 7:22 pm

Does anyone have any experiece with the three dog/close ratio gear sets? Pros and cons?

silverfish
Cucciolo - the Lil Pup
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Post by silverfish » Thu Oct 28, 2010 11:10 am

It works great on a racer,but not so good on a streetbike as you probably have to have like 15/46 gearing.
1,2,3 is on my veetwo gearbox higher and 4,5 std.

I tried it in a streetbike with straightcut primarys and it didnt run under 55 kph with 15/40 gearing.


Kent

wdietz186
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Post by wdietz186 » Fri Oct 29, 2010 7:30 pm

The three dog gears were for racing boxes to make them shift more positively in racing conditions.Not really needed in street usage.Years ago people used to modify the stock gears by grinding off three of the dogs and undercutting the three that were left.

Desmo-Kid
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Post by Desmo-Kid » Thu Nov 25, 2010 6:42 am

The gears (I don't remember if it's all of them) have 3 long and 3 short dogs. Short dog engagement has far less bearing area and can result in "slipping" during acceleration, followed by long dog engagement, which won't slip. High forces can be generated during this slippage, which feels like a lurch. These forces can cause damage, most likely to shift forks.

When shifting it is hit or miss whether one gets short dog engagement or long dog engagement...luck of the draw.

Grinding off short dogs solves this. The price you pay is a significant amount of backlash when going from on to off throttle and vica versa.

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