This note from Dakota Digital apparently assumes you don't have PowerVision or any other tool to change the "factor" stored in the ECM. But, if you have PowerVision or another software tool that can change the factor, there should be no problem because you don't get outside the +/- 3% error range - you can instead make the new "factor" exactly correct.

Jim G

 

LOL. We'll I'm hoping that HD at least wrote in some logic that actually looks at the gear ratios table as part of the 'ratio window' determination. there is really not enough data out there to find on this. most of the forum solutions have centered on messing with the VSS and pulse settings as a means of correction. No one has tried altering the gear ratio tables.

I would suspect that may actually work since it is obvious the touring bike and non touring bike strategy ecm files are universal across their respective models. The ecm would have to take into consideration model specific variables such as injector size, engine size, gear ratios, etc to make any sort of accurate determinations.

We won't know until we try, eh?

 

Yes but I don't see a specific table entry exposed for that ratio window in PV. As far as we know that ratio window could simply be a calculated result based on the gear ratio table and vss setting, and not an actual parameter itself. lots of guessing!

 

I don't have time to look for it, but I know I have seen instrucitons somewhere on the specific field name to alter via PowerVision.

It is entirely correct that only ONE field needs to be altered, because while HD alters both prim ary and final drives from year to year and model to model, they do NOT normally alter internal gearbox physical ratios. So, once you have determined the "new" overall driveline ratio created via physical items you have changed, you can multiply the existing factory "factor" by the ratio of new versus old, and everything, including speedometer, gear lights or digits, and ABS logic, should be correct.

On cars, this is exactly how it is done. When in 2006 I changed the physical rear axle ratio on my Chevrolet SSR ("retro convertible pickup") from 3.73 to 4.54 (22% change!), sure enough the ABS system AND speedometer were both wrong and complained. Changing just one factor field in the software tool that we used to program for the supercharger tune, corrected the problem instantly and completely.

I also did something similar for the 2010 Mustang I supercharged. The gearing change there was more modest, but with the combination of gearing and supercharger, the car still made it through 1st gear so fast that anyone who was not used to it bumped the rev limiter before they could react. Laid rubber ALL the way through 1st, even with 3 men in the car.

Jim G

 

Sure- I agree and hope it is that way. Oh how I wish that our HD Delphi was the same, un-adulterated and full featured automotive Delphi. there are so many tables and options missing that would be of benefit.

I'm looking in my WinPV and the only related tables are "gear ratios" (1st through 6th ratios) and "speedometer" (VSS pulse per mile). Well if I lose my 6th light after the 70t rear pulley swap then you can bet dimes to donuts I'll find out what works to fix it and what does not -

But I suspect that I'd only see the issue after changing the primary drive ratios, not the secondary. When I swapped from 32/66 to 30/68 I still had my 6th light even though my actual displayed speed was wrong, before I updated the VSS setting.

 

FYI- I asked the site owner at GearingCommander (http://www.gearingcommander.com/) to add the Breakout to his bike database-

You can go there and load the default gearing / tire data for Harley>Softail>FXSB and then see changes easily by altering front / rear pulleys, tire size, primary drive ratio, etc. - there are graphs for rpm, mph, comparatives based on different pulley sizes, etc.

Its a fairly handy online gear calculator tool to use for HD bikes and probably the easiest one I've found- If you like the site consider a small donation to the owner (I have no affiliation).

 

So I have my test pulley, 1/4" pulley offset spacer and 1-3/4" grade 10 pulley bolts. final measurement checking shows that the Arlan Ness pulley with the 1/4" spacer is within 1/32" of the stock pulley offset. that should be close enough. the wheel bolt length was determined based on the thickness of the pulley bolt seat (1/4") and spacer (1/4"), and the need to have 1.25" of bolt thread into the wheel. I took some pics of parts and the measurement process I used to determine my offset spacer thickness. Note that if I were using a stock HD pulley like from a 2006 Street Bob or other dyna (also a 70t pulley, 1.125" wide), I would not need the offset spacer since HD molds the spacer into their pulleys. This is why the 2011 68T sportster XL1200 pulley is a direct bolt on. I suspect the 2006 Dyna pulleys will bolt on directly as well without need for spacers.

Now all I have to do is see if I have the extra 0.31" of belt adjustment to put this sucker on. It looks like I have just under 1/2" of slot left so it's gonna be close!

Nine large PICS below so let them load:

Arlan Ness pulley #16-531 for a 2004-2006 FLHT (70t, 1.125" wide), Drag Specialties 1/4" pulley spacer, industrial Grade 10 round head socket cap screws 7/16" 14 x 1-3/4"
(you need at least grade 8 for pulley bolts)
Order pulley bolts from American Integrated, phone number is on the 2nd photo (bag of bolts). Best price you'll find and ultra high quality. They have all lengths / sizes.






DS spacer placed onto backside of Ness pulley:


New round head 7/16" socket cap bolts for pulley - should sit nicely in there.


Measuring and checking pulley offset - stock pulley on stock wheel. lay straight edge across pulley face and measure from ground up to top outside edge of pulley.
your new pulley must sit at that same height so you would get the appropriate thickness spacer to push it outward.
in this case I needed 1/4" and the DS .250" spacer was $9.95


remove stock pulley, place spacer onto wheel hub


place Ness pulley onto wheel, on top of spacer. hold with a couple of bolts.


side view of DS spacer between pulley and wheel hub


checking offset measurement of new pulley and spacer- in this case I am within 1/32" of the stock pulley outward measurement. not bad.


Part 2 coming hopefully this week, and hopefully with positive results!

 

anxious to see how you like the performance of the new gear change...been following your journey to gearing perfection

 

Fabulous write-up and photos LA_Dog!! Thank-you!

Jim G

 

Jim- everyone- it FITS!! no problemo- Woot!! Belt just barely slides right over and there is plenty of belt adjustment. About 3.5 turns out on the adjusters and then aligned with my micrometer.

Pics coming later - I can't test ride it today due to rain and wet roads. but I've run the bike on the lift and it tracks true.

Offset is right on the money with the sportster sprocket and stock sprocket. this is with the 1/4" spacer of course, since this fancy billet pulley didn't come with enough offset for a 240 tire- but good thing is, spacers are cheap and plentiful in all sizes.

I wasn't too overly worried based on the math- calcs said I needed 0.31 of added belt adjustment and I had about 1/2". but heck you never know 100% until you bolt it up.

So Jim- no reason you can't buy one of the chrome design HD or aftermarket (RSD, PM, BDL Ness etc) 70t pulleys for a 2004-2006 FLHT or 2006 Dyna - something that will match with your CVO wheels. As long as the pulley has the 2.20 hub hole for 2001-up FXS/FXD bikes without IDS (cush drive) and is 1" to 1.125" wide you're good to go. the five hole bolt pattern is same and the axle size or axle spacers do not matter. Once you have the pulley, you would only need to determine the appropriate hub offset spacer and length of bolts- which is not hard to do. Once you have the parts this is no more difficult than replacing a rear pulley.