EYES!!! Gentlemen, I need some wisdom. I have a 2003 RK Police, I'm shooting towards a direct driven 6 speed transmission. I've read about the differences between the direct drive and the overdrive trans and gear sets, and though it may be slight I'd rather not lose what power might be lost in an overdrive gearing system. I don't want to buy an aftermarket brand and I don't want to spend $2800 on a new trans from Harley, so my questions are;

Will a trans of a 2008 street glide bolt up to my '03 stock 88?
What other years are compatible?

This is a link to one article that was helpful in my decision in case any of you others are thinking about this kind of upgrade.

http://www.harley-riders-guide.com/h...six-speed.html

 

No, a six speed OEM transmission is completely different, and will not work with your transmission case. The only way to go 6 speed is an aftermarket gearset that is designed to be used in a 5 speed case.

 

I wasnt asking if the OEM six speed gear set will swap to my 5 speed transmission case. I understand that the trans cases of an OEM six speed and an OEM five speed are different. I'm asking if they can be swapped out as a whole. Will a complete '08 6 speed transmission, trans case, gears set and all bolt up to my engine crankcase. Is the marrying pattern the same?

 

No.

The 08 is a TC96 and that 6-speed trans was introduced by HD with the TC96. The interface between trans and engine was changed at the same time, so a TC96 trans will not fit your TC88.

You can buy a factory 6-speed gear set to fit in your current trans casing, or a complete trans, as was fitted to early 6-speed SE models, however I believe that is OD, not DD. You may be lucky and find a complete OD trans from a broken SE bike.

 

That was the answer I was looking for, thank you

 

Are there any aftermarket brands/companies that make a direct driven six speed for the TC88.

 

While I realize this thread is a couple months old, I would suggest Baker if you want to go aftermarket. It won't be cheap but IMHO it is as good or better than OEM.

 

There are very few 6-speed aftermarket gearsets! Harley sell an OD set that will fit your TC88, as do JIMS, Ultima and Zodiac. Baker sell both OD and DD 6-speeds and that is about it I'm afraid! Current Harleys have a DD 6-speed, but that does not retrofit, which AFAIK leaves you with just one option, as ChromeJunkie points out.