Addressing that Rigid Front End

[Valkflyer]

Here’s a little something for those of you that have been wrestling around with that hard front-end issue.  About a year ago year ago I purchased a set of Progressive 440 HD’s and fork spring in order to replace my stock components.  Like many of you what I ended up with was more than I bargined for, a very stiff responding front end.

In my maddening attempts to address the problem I have tried just about every thing, including changing out the rear HD springs for Standards, and then adjusting them from one end of the spectrum to the other in order to try and strike a balance between my forks and shocks.  Not much help here…..

I also tried inserting fork spring spacers, running multiple viscosities, as well as manufacturers, of fork oils.  I experimented with fork oil levels, and yes replaced my bushings and seals; I swapped out my steering head and wheel bearings.  I even tried different tires.

I was just about to give up when it dawned on me that I wasn’t dealing so much with a spring issue but more a damper issue.  And my thinking then turned to clarifying at what point I was experiencing the problem; an immediate harsh jarring whenever I struck a small or large bump.  A jarring I could feel through my handlebars.  

Well I’m not an expert, and I may be off base about the workings here but the thought I settled on was that the oil was not moving through the damper collar quick enough to create the steady and smooth compression needed.  That this was probably due to the fact that Progressive spring were radically different in their operation than the stock Honda springs, and because of it the oil was now flowing more slowing through holes in the collar, retarding the compression.  Ok, sounds far fetched but at this point I’ll try anything.

So why wasn’t changing the fork oil enough?  Well I believe the answer to that, in this particular case, is that a quicker compression stroke is needed but the recovery stroke needs to remains as is.  Changing the fork oil means that the damper still travels in both directions at the same rate no matter what the viscosity.  Pure speculation but I though I would at least look at it that way and see what I ended up with.

The way I see the collar working is that as the spring compresses within the Slide Pipe, the fork oil is forced from the inside of the damper collar, through the two side holes near it’s base and ring piston.  The oil passing through the lower holes addresses the compressing/damping stroke while the two holes at the top address the recovery/damping stroke.  My guess is that there still needed to be some sort a balance between the two and that adding the new Progressive Springs some how changed that.  So I decided to start with a minor change and see what I ended up with.  

The change I’m referring to is drilling an additional hole ~ 3/8th at the base of the damping rod collar.  As it turned out the result was amazing, nearly removing all the jarring!  It wasn’t perfect though and I had to get greedy so I added one more.  That turned out to be a little less effective though so the key is one only.  Again, I just got lucky on this one so who knows what would happen by adding another hole for recovery at the top, or then again different oil following the addition of the 3rd hole.  Maybe someone else can run with that one.  What I do know though is that there’s been a major improvement in my front-end damping and I ‘m a heck of a lot more happy because of it.

FYI,
I’ m running Bel-Ray 15w at the recommended levels, per Progressive.
My 440’s are 12.5 inches and have the Standard springs installed; these are wound down 5 turns.
My weight is 245lbs.
I’ve not tried it with my wife on he back yet.
I hope you all who need it find this helpful.

Sorry about not being able to add the pictures, I'm new and couldn't figure it out.

P1010392.JPG

[DFragn]

Some have suggested sticking with Honda's recommended SS-8 which is a 10w in place of progressives suggested 15w. I use the SS-8 10w with my Progressives.

But, something doesn't sound quite right. You description of jarring bars and harshness seems unusually harsh.

I've experienced a wide variance window between fluid levels alone. Reducing them increases the amount of air in the tubes thereby softening the response. Air compresses fluid does not.
I'd beg to wonder if something else isn't amiss. Perhaps the plunger seals within the oil dampener have failed?
Where are your dampener rod lock-nuts positioned on the threads below your fork caps?
Is it possible the spring seat stopper in the left leg is sort of standing on end? I had that washer not laying flat on the spring once and it seriously hampered the left side dampening ability making it very harsh.

Don't think I would be wiling to drill my fluid dampener cartridge. There are so many control routes other then that.
And, as far as I know your the first in over 10 years on this Tech board to drill the dampener.

[PAVALKER]

I also think the fork fluid was/is the issue....but that is my opinion.  I have not heard of others drilling relief holes in the damper either (not saying it has not been done, just not widely promoted).   I have recently installed Progressive fork springs on my IS, and used AMSOIL Fork Spring Suspension Fluid (which I believe is medium or 10wt depending on who you talk to).  I have the fluid levels a little more than recommended, to provide additional firmness, but the lighter weight will assist in the flow.  The front end is firm and tight but not quite rigid and I don't experience that harshness you seem to experience.  Matter of fact, before the swapout of springs, seals, bushings and fluid it felt harsher than it does now, but not as firm as it does now.  The fairing was tightened up a bit when I did the springs, seals, stem bearings etc, and it now does not make noise when crossing tracks or on bumps.  I'm from Pittsburgh PA and we have more than our fair share of pot holes and rough roads.... and all is well (so far). 

I believe there could be a variety of issues causing a certain problem, and one remedy might not work for someone else or their ride.  A simple thing like shock bushings or even tire pressure could cause a perceived problem in the front end, so make sure to check it all out and do what works for you.

[Daniel Meyer]

Keep in mind that the dampeners are not the same in both forks. One works on the downward stroke, on on the upward...

[Valkflyer]

Figured this one would get some feedback, thanks for being thoughtful and nut just attacking, I realize I may have just lucked on to something hear, and yet did'nt fix the real issue....not good...  Well I did say I’m not an expert, but I have pulled the springs and replaced the fluid countless times attempting to remedy the issue.  In fact I can do it with my eyes closed now, just kidding…And yes on the left fork I’ve even had the spring plate positioned incorrectly before, but I corrected that after finding it difficult to reseat the collar bolt.  As far as the positioning of the damper rod lock-nuts, I’ve experimented with these also believing that moving them up and down would act similar to the way you’d adjust pre-load on your rear springs.  Don’t get me wrong changing the fluid, and making small adjustments in the lock-nuts did impact the ride, but in my case not to the point of addressing this low end rigidity.

The one area I’ve not looked at that was mentioned is the plunger seals within the oil dampener, but if these had failed wouldn’t it be apparent once I started to pump the rod in order to fill it with fluid.  Mine remains firm after pumping it about 6 times?

To Daniel’s point, can you help me to understand how the two function a little more?

[asfltdncr]

This is probably way out there so don't laugh but would installing Progressives upside down in the fork tubes cause such a problem?  They will easily go in either way.  I recently installed Progressives and used 10w Honda (a little Yamaha because I didn't order enough Honda) fork oil and am quite happy with the performance.  They are stiffer than stocks but not at all abrupt. 

[DFragn]

This is probably way out there so don't laugh but would installing Progressives upside down in the fork tubes cause such a problem?  They will easily go in either way.  I recently installed Progressives and used 10w Honda (a little Yamaha because I didn't order enough Honda) fork oil and am quite happy with the performance.  They are stiffer than stocks but not at all abrupt. 

No. There's very little difference with taper up or down. Most would never be able to tell.

[DFragn]

Well, I'd imagine by the lack of responses that quite a few of you most likely think I'm some kind of nut job by what I've shared, but here's the deal.  When I say rigid I'm referring to those small or harsh bumps we run into.  It's not my springs that didn't function properly, they operated well, it was damping, and my ride would go from smooth to a sharp vibration depending on the road.

The next thing I wanted to clear up was that I was not talking about compressing liquid, but instead the rate in which it would pass through the collar in order to compress air.  In any event, the adjustment really did help but I wish it was even better.  I'm probably just to picky, but you'd think after 70K miles I'd know a little about how my bike should feel, maybe it's age...now what was I talking about?  Who am I? Where am I?   Oh yeah, ah...ok...

Oh well if anyone would like to share with me more about the functionality of the two forks I'd welcome your input.  And thank you to those that did respond!!

You received an average number of responses based on your total thread hits. For this board anyway.

My impression is you desire an overly plush ride up front. Maybe something inline with an HD front suspension system. And, you just don't like it. That's fine.

Honda engineers along with Showa designed these front suspension systems in direct relationship with the bikes power, weight & handling characteristics.

Then you modify the right fluid dampener to increase compression/rebound flow. Something I disagree with, but ok. As I mentioned the two forks work in unison. You can't seriously alter one side and not the other. How to alter the rebound/dampening in the left. I'm no engineer, but no idiot either. All you can do in the left is with springs, fluid and a slight dampener rod adjustment.

You could add "Gold Valves" [from whom I don't recall], but I don't know if that will give you what you want.

Perhaps it's time to search out and replace the entire component system in both forks or just replace everything including the tubes. I imagine that could cost between $1,500 & $2,500. I believe you're asking way too much from the existing system. There's a limit of what can be done to these fork systems.
My guess is, because of the tube diameters, you would end up with aftermarket sport bike suspension. Hey, maybe that's a good idea considering sport suspensions are designed for bikes half of the Valk's weight.

[X Ring]

Last spring I had my forks rebuilt by an independent shop with Progressive springs and the shop used Honda fork oil.  I don't have a harsh ride.

Marty

[Ricky-D]

I test my Valkyrie front end by riding over speed bumps in the parking lots around town.

I use mph's as the measure of how well my front end's shock absorbing quality is doing.

At less than 5 mph it doesn't work too well and the bike gives me some pretty good jostling.

At 10 mph it gets progressively better and over 15 mph the bike traverses the speed bumps extremely well and the ride is surprisingly comfortable.

I guess what I'm trying to say is that the ride has a lot to do with our own self imposed limits and riding ability, a good understanding of how things are supposed to work and a real desire to continue to being open to reality.

Ever notice how chewing gum gets tougher and harder to chew as you chew it.

This sounds like kinda the same type of situation.

***

[Valkflyer]

That’s probably just what I needed to hear, this is freggen Harley country out hear and Valks are few and far between, it’s a darn shame considering how great a bike they are.  I’ve not made an effort to find others to compare it to.

I’ll have to admit that once I started making the changes I guess I just convinced myself it should be better….

DFragin, I had that one coming, I apologize.


Thank you all for taking the time.

[DFragn]

That’s probably just what I needed to hear, this is freggen Harley country out hear and Valks are few and far between, it’s a darn shame considering how great a bike they are.  I’ve not made an effort to find others to compare it to.

I’ll have to admit that once I started making the changes I guess I just convinced myself it should be better….

DFragin, I had that one coming, I apologize.


Thank you all for taking the time.

Good luck with your quest.
Post up if you find a solution 

[Daniel Meyer]

To Daniel’s point, can you help me to understand how the two function a little more?

I can't remember which fork is which...both have springs and dampeners, but the dampeners only work one direction. One only slows/dampens on the downstroke, the other only dampens on the rebound.

[Ricky-D]

A little mistaken there!

The only dampening on the rebound occurs in the right side shock only.

Any and all compression dampening in either shock is from the springs .  Some will say the oil has some dampening affect and some will say as the air compresses, it also has a dampening affect.
I'm not so sure about those two and Honda makes no claims either.

***

[DFragn]

A little mistaken there!

The only dampening on the rebound occurs in the right side shock only.

Any and all compression dampening in either shock is from the springs .  Some will say the oil has some dampening affect and some will say as the air compresses, it also has a dampening affect.
I'm not so sure about those two and Honda makes no claims either.

***

Well, if ya add about 6 more ounces of fluid [which will be about 4.5" more of fluid height and the same measurement deceasing the air amount you'll find your Valk riding like a "SteamRoller".

If you drain all but maybe 5 ounces of fluid [just enough to keep the springs lubed & quiet] you would have quite a supple ride.

In both cases it would handle like crap and be a potential danger.

Hence there's a reason manufacturers spec particular fluid quantities.

[2qmedic]

Any and all compression dampening in either shock is from the springs .  Some will say the oil has some dampening affect and some will say as the air compresses, it also has a dampening affect.
I'm not so sure about those two and Honda makes no claims either.

Spring design, oil weight and air all work together.
1-Design of the springs used is obvious.
2-Oil weight (thickness) plays a factor also. The thicker the oil, the slower it will flow between the two sides of the orifice.  Thicker oil will have a firmer feel, thinner oil will give a smoother feel.
3-Air is compressible, oil is not. Many do not understand this principle. Take a 2 liter coke bottle, fill it with water and cap it. Now try to squeeze it. No can do.
Now empty a cup water out. Squeeze the bottle and you can squeeze it some.
The more air in the bottle = more compressibility.
This plays a part in the operation of the forks. If you fill the forks full of oil, they will feel like solid forks. Reducing the oil increases the air capacity. When compressed,  the air allows a cushioned response. The larger air capacity, the more cushioned (softer) effect.

Honda did the R&R to come up with the manufactured requirement. Changing any one (springs, oil weight, or amount of oil (air capacity) will have an affect on the operational characteristics.

Ya'll have a nice day