Here are a couple of points to consider when replacing fork springs with something other than stock.

1. The oil level in the tubes can be accurately measured whether the forks are vertical or mounted in the trees. If the forks are mounted in the trees, take the measurement at the center of the tube not from an edge. It will measure the same as it would if the tube was vertical.

2. The amount of oil that goes into the fork tube is based on oil level NOT quantity. Yes, the HD Service Manual specifies an oil quantity but it assumes that you are using HD fork springs and it has calculated the number of oz.'s needed to achieve the desired level in the tube.

3. As many have noted, the Progressive instructions here are somewhat vague, listing an oil level and also refering back to the HD manual which lists a quantity.

4. Fork springs other than the stock HD's will likely displace a different amount of oil when they are inserted into the fork tubes and as a result will affect the oil level. Generally, the desired oil level in the tube, as measured down from the top with springs installed, should be the same regardless of the springs used. Progressive's displace more fluid than stock springs thus the lower level (by .25") when filling before the springs are installed.

5. At this point, because of the difference in the amount of oil displaced, it should be obvious that the springs should be inserted into the fork tubes when filling to the proper level unless the spring mfg. has given a clear and precise quantity of oil to be installed in the tubes.

6. If you measure the oil level in the tubes before removing the old springs, you will know the correct oil level for the refill. (Assuming of course they were properly filled in the first place and not leaking)

7. Overfilling will result in blown fork seals.

Just my .02 & it's worked for me.

 

Back to the original post...if your springs are different lengths...your kit was mis-matched.

Fix that screwup first...then read the directions and do exactly what they tell you to do.

It's that easy, really.

 

His OP indicated he was confused by the directions.

 

SM's and installation instructions are meant to break things down to simplicity....if you can't understand it, you probably shouldn't be messing with it in the first place.

Now if he's confused because of the directions in the SM conflicting with Progressives (which is what I gather from reading through all these posts)...then he should use Progressive's directions.

I'd think their directions would be accurate for their product. Doesn't take a "mechanic" to read, look at pictures, and install a kit that's mass-produced.

 

Obviously, you have never read Progressive's conflicting and confusing instruction sheet. [:-]

 

Just did...and it says to use the SM's specs...or call their tech line...number provided...for clarification.

I read through the instructions and I really don't see anything confusing in them at all. They even break the detailed diagrams down by year and model.

We are talking about the PDF for the Harley Fork Lowering Kit, correct? Seems like they give you everything you'd need...aside from oil capacitys and measurements...which recommend the OEM viscosity and level, along with EXACTLY how to fine-tune damping using different weights. Which honestly shouldn't be considered and/or attempted by anyone other than a professional or someone that understands how these changes will affect handling and has experience dealing with this.

Seems pretty cut and dry to me.

 

I don't see anything in the OP about this being a fork lowering kit, just a progressive spring replacement. If his kit is like what mine was, it contained 1 page of installation instructions and confusing info. on the amount of oil to use. It specified an oil level and then suggested you refer you to the SM which lists an oil quantity. There was no breakdown by bike model.

Have you ever installed a Progressive spring kit?

 

A replacement set!? And that's confusing....HOW? Wow...pretty in-depth for something so un-complicated.

A lowering kit made more sense, to be quite honest. [>:] Which is why I thought that's what he was dealing with.

This thread is officially overkill.

 

I guess it is, for your superior intellect.

 

Its not superior intellect...it's common sense. Take it apart and put it back how you found it. As far as how much or what measurement to use...do whatever suits you. Either way should work, according to that SM, so really, use good judgement and you should be fine. And again, if you're uncomfortable or unsure, DON'T do it yourself.

Like I said....pretty simple, really.

Going in-depth about how and why will only confuse him more...as it does with most people. You're trying to say that it's an exact science when it's really not. Things like valve clearances, timing, electrical, and tuning are exact sciences, not filling your damn fork tubes with oil.

I fail to see wherein his original post he mentions how detrimental his fork damping and suspension tuning is to how his bike handles. He's just trying to fill them right for normal use. If he were racing it, I'd see the point, but in this case, there isn't one for all these matter-of-fact measurements and analyses.

Bottom line:

[sm=icon_rtfm.gif]

And if you still don't know...leave it the hell alone before you kill yourself or destroy your bike.