Author Topic: gear shift drum?  (Read 754 times)

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Offline Zig

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gear shift drum?
« on: May 14, 2010, 11:48:25 AM »
Hay all.
5 (indexing??) pins on end of shifter drum are not square to drum. Will this create a problem??

tia, zig.
« Last Edit: May 14, 2010, 01:55:12 PM by Zig »

Offline KRONUS0100

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Re: gear shift drum?
« Reply #1 on: May 14, 2010, 11:55:31 AM »
ummmm..they look twisted.  might cause harsh shifting or hanging up in gear
MATT
current bikes:  1976 CB750F, 1981 GS1100E
bikes owned:1981 GL1100I, 1990 GS500E, 1981 GS850, 1977 and 1979 GS750, 1974 CB750, 1975 CB750, and a 1982 GS750E

Offline Zig

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Re: gear shift drum?
« Reply #2 on: May 14, 2010, 11:58:42 AM »
ummmm..they look twisted.  might cause harsh shifting or hanging up in gear

is some other evidence po was hard on gearbox, will check on cost for a replacement.

Offline mystic_1

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Re: gear shift drum?
« Reply #3 on: May 14, 2010, 06:21:57 PM »
Wow, never seen that before.

You should be able to score a shift drum fairly cheaply.  Make sure you get the same style as you have now, earlier ones had different arrangement of plates on the end and correspondingly different detent arms.

mystic_1
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Offline scottly

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Re: gear shift drum?
« Reply #4 on: May 14, 2010, 06:49:17 PM »
Could it have been incorrectly assembled?
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Offline bwaller

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Re: gear shift drum?
« Reply #5 on: May 14, 2010, 06:51:20 PM »
Is the screw loose?

Offline mystic_1

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Re: gear shift drum?
« Reply #6 on: May 14, 2010, 06:52:31 PM »
The pins sit down in holes that are drilled into the end of the shift drum.  In order to be deflected that much, the pins are bent or the holes are trashed.

mystic_1


Edit to add:  On the drum I just measured, four of the holes are 5mm deep, and the fifth is 9mm deep.

mystic_1
« Last Edit: May 14, 2010, 06:54:04 PM by mystic_1 »
"A ship in harbor is safe, but that is not what ships are built for."
- John Augustus Shedd

My build thread:  http://forums.sohc4.net/index.php?topic=68952.0