G'day all, well one of my dreams would be to fit a six speed gearbox to my Evo Heritage Softail.  

Ok I am talking about a overdrive in sixth gear just to drop the revs down a bit while out on the hi-way so just wonding has any member here done this and if yes was in worth it.

At the moment it's just a dream no funds to do this sort of work but feedback is always a great thing to have whether it's good or bad cheers.

Not sure if my feedback is relevant for you but will offer it anyway. I have a 6 speed gearbox in my FXR. I had the 6 speed in when the Evo 1340cc (80ci) was still in the bike, but my Evo went to heaven about 5 years ago and I put an Ultima 1760cc (107ci) in.

I can only report my experience but I rarely get to use 6th gear. I used to live in Canada, where freeway speed limits are 100 or sometimes 110, but speed tolerance is higher so you could do 125 no issues. At that point 6th gear was great, lowering my rpm to 2800. But here, especially in Victoria as I live in Melbourne, speed tolerance is lower and 6th gear below 110 has too much potential to lug the bike. Sometimes, on flat roads with no wind, perfect conditions will see 6th gear purr at about 2700 rpm, but it doesn't take much for that to become 2500rpm and the lugging it stage. Basically, I am now happy to use 5th gear!

Anyway, that's my experience. Rarely does 6th gear get a look in and only if on the Hume Hwy in a 110 zone where I am doing 120 and anxiously keeping an eye out for fixed cameras! At least with my 107ci with Mikuni 45 carb, below 115 and 6th tends to lug unless riding conditions are just right. So I guess I am saying it becomes speed dependent whether 6th gear has a point (assuming cost is an issue).

But that's just my experience. Maybe someone with a different setup finds 6th gear can lower there rpm range to the sweet 2800-3000 without dropping lower to lugging territory, if below something like 115.

Hi, What  gearing is it running, stock I think could be 65 tooth rear pulley 32 front, or maybe 70 tooth rear, if 70 tooth rear could run 65 tooth for better highway cruise. I have a six speed RSD box in my chopper, rarely get into 6th, only on back roads where less chance of police. Mine cruises at 2500 at 100kph in 5th. I run 65/32 pulley combo, never get into 6th unless doing 110 to 115 then revs are only 2400 borderline on lugging engine...........

Ok thanks for your replies so far.

As I said it's just a dream at the moment and I enjoy getting your feedback on what I asked, I am sure your replies will be read by others with five speed gearboxs who may be thinking of going to a six speed box so all info helps cheers.

Been thinking about the same thing for quite a while as well, Choco. Seems the blokes I ride with like to push it up a little and I always feel like I'm starting to wring my old Evo's neck to keep up.

If the exchange rate was a bit better, I might have had a six speed in by now, that's one with overdrive. A Bakers or Jims, with maybe a direct drive with different pulleys or sprockets would be nicer, but I can't justify the cost.

You might also consider changing the transmission and/or rear wheel sprockets (pulleys) to get the ratios more to your liking regarding rpm and speed, or even the engine sprocket, I believe, all of which will be cheaper than a new transmission, but you'll lose a bit of pulling power of course to get those longer legs.....

Had an S&S 6 speed in my evo Heritage. The bike was built for long runs and the 6 speed was perfect. Another mate is running the same box with an S&S 96, great combo. A pity that they no longer make them but it was worth every penny. Sold the bike with the 6 speed in it.

Have had a ultima 6 speed in two different softail now since 08 about 25,000k on that one and have new one
In my other softail that I'm building at the moment for the price I reckon there good value but as others
Have said no need for sixth under 110 or so Great for the open road though you can sit on that sweet
Spot evos love 2500 to to 2800rpm around $120 or so With a 32 f 70 rear

What about going up a couple of teeth on the gearbox pully ... will be just a little more sluggish off the bottom but not much as the Standard 1st and 2nd gears are so low anyhow and it gives you that little bit more comfortable rev range in the mid and high range .

Far cheaper option than getting a complete box ... I went up 2 teeth on both my 99 Springer and just recently on my 08 Softail as well ... don`t think I will ever use 6th gear again but that's ok .

My Springer had the bigger front pully from the get go when it was put together so cant really offer any rev range figures for you ... but just recently after doing a rear belt decided to try it on my 08 and so far I reckon it is great ... something like a 3 to 4 hundred rev range drop ... which of course translates to a higher cruzing range in 5th at the same revs as before .

Used to sit in 5th on a hundred and felt just a bit off , like it was working just that little to hard ... was perfect at around 110 / 115 but sadly cant ride at that speed all the time ... although my mates might disagree , Lol

Leaving it in 4th meant it was reving just a tad to high for my liking ... so now it seems to be just right in 4th at a hundred ... with mine I had a speed sensor adjuster installed to compensate for the different gearing and still have to do some speed checks with a few mates to double check that my speedo is right but fingers crossed it should be fine .

Will post up the results when I get a few of the guys together to help with the speed runs .

Cheers .