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Old Aug 10, 2017 | 01:05 AM
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Default Transmission Swap

Hey guys!.....I have a 91 Heritage softail that I want to swap out the tranny for a 98 softail tranny. Looking to do this mainly to lower rpms at highway speed. Are there any changes I need to make with the primary, compensating sprocket, starter motor etc.? or will she bolt right up? Thanks!
 
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Old Aug 10, 2017 | 08:42 AM
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They will be a direct swap but you are trading one 5 speed for another. The ratios are still 1:1 in 5th.
 
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Old Aug 10, 2017 | 02:09 PM
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Thanks for your reply Mark. I also have 95 Softail Custom that at 75 or 80 mph the rpms and vibration are not near as bad as the 91. This is why I thought of doing the swap. Is there another possible contributor as to why the 95 doesn't feel maxed out at highway speeds? Thanks.
 
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Old Aug 10, 2017 | 07:26 PM
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Gearing is why
 
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Old Aug 10, 2017 | 08:24 PM
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Right.......So Am I not going to achieve the results that Im wanting?
 
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Old Aug 11, 2017 | 08:39 AM
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Originally Posted by kanders70
Thanks for your reply Mark. I also have 95 Softail Custom that at 75 or 80 mph the rpms and vibration are not near as bad as the 91. This is why I thought of doing the swap. Is there another possible contributor as to why the 95 doesn't feel maxed out at highway speeds? Thanks.
The difference is in the primary, your 91 has a 24 tooth motor sprocket and a 37 tooth clutch sprocket. Your 95 has a 25/36 primary combo.
 
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Old Aug 12, 2017 | 08:06 AM
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I don't know how much you want to spend, but if you want to fix it right let Mark fix you up with a 6 speed. You will be glad you did!
 
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Old Aug 12, 2017 | 01:06 PM
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Originally Posted by TN Houndog
I don't know how much you want to spend, but if you want to fix it right let Mark fix you up with a 6 speed. You will be glad you did!
I wish I could afford a DD6......just cant right now.
 
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Old Aug 12, 2017 | 01:32 PM
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Originally Posted by Mark@ Baker Drivetrain
They will be a direct swap but you are trading one 5 speed for another. The ratios are still 1:1 in 5th.
Can't count the times I've had guys argue that with me, a few got down right pissed off about it.
 
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