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Old 12-17-2009, 06:14 PM   #16
zenben
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Quote:
But before I did that, I would probably install real cartridges.
Agreed. If one can bear the cost, this would be the ideal solution.
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Old 12-23-2009, 01:52 PM   #17
2whelman OP
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Quote:
Originally Posted by AntonLargiader
That would be my approach, too.

I think there's still (and always will be) some misunderstanding of these forks. Which are IMO the best forks ever used on Airheads.

Whereas there's always damping whenever something moves through oil, inspecting the internals leaves me with a crystal clear concept of how the majority of the damping takes place. Take a look at my web page and you might see things differently.

In the left there is travel-dependent damping (WAD in BMW-speak) affecting compression and rebound. The spring support is nothing more than a guide for the end of the damper rod; it is cutaway so as not to impede the compensation flow.

In the right there is a rebound piston with a check valve to negate resistance upon compression. However, because the spring support has to seal (to provide the rebound damping) there is typical damper-rod compensation flow. Displaced oil goes into the bottom of the damper rod through the existing holes and out the top, in the middle of the spring seat. This flow is what the Gold Valve sees.

So you probably have some small degree of damper-rod compression damping in the right leg, but I doubt that drilling more holes in the damper rod changes it. The internal diameter and length of the damper rod is probably the flow-limiting factor. In the grand scheme, you are retaining all of the existing compression damping because the left leg is unaltered and the right leg is probably unaffected by the extra holes.

It's very possible that the GV provides better damping than the stock setup. The WAD works on the full volume of oil in the fork tube, whereas the GV only sees the compensation flow. That's probably less harsh. So if I were to do this, I'd probably alter both fork legs and rebuild the damping completely.

But before I did that, I would probably install real cartridges.
So, correct me if I misunderstand, are you saying the gold valve is not going to alter the front end dive? I am not looking to make this into a world class, Dakar racing, ditch eating front end, I just want less front end dive on braking, everything else about the fork is perfectly fine for my use.

I have installed the emulators in other bikes, they helped, some of the bikes they helped A LOT. I dont want to bother if it isnt going to help.
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Old 12-23-2009, 05:36 PM   #18
AntonLargiader
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Quote:
Originally Posted by 2whelman
So, correct me if I misunderstand, are you saying the gold valve is not going to alter the front end dive?
I didn't say that.
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Old 11-02-2010, 06:07 AM   #19
espressodrinker
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What are "real cartridges" ?

It's very possible that the GV provides better damping than the stock setup. The WAD works on the full volume of oil in the fork tube, whereas the GV only sees the compensation flow. That's probably less harsh. So if I were to do this, I'd probably alter both fork legs and rebuild the damping completely.

But before I did that, I would probably install real cartridges.[/quote]

What are real cartridges?
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Old 11-02-2010, 01:05 PM   #20
supershaft
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It's been awhile but don't emulators have adjustable rebound AND compression damping? If that is the case, I am with Anton. Why put one in just one leg? They are a pain to adjust but why install them if you are not going to set them up?

I know I have been preaching the same sermon lately but this is yet another case where someone is going about fixing an issue ass backwards. The issue is excessive dive. You don't fix that with damping! You fix it with spring and preload! Think about this: What little you can reasonably fix excessive brake dive with damping should be fixed by learning to get into the brakes a bit more progressively in that first instant of braking. More compression damping is just slowing down the inevitable compression of the SPRING. Your fingers can do that via brake control. I am not saying that there is no need for compression damping. There is. My point is to ask not what your compression damping can do for you but what you can do for your compression damping. Let it do it's job and don't expect damping to do the job of the spring. Damping is there to help the spring, not BE the spring.

My advise is to avoid setting up your front end for braking. Watch your favorite world class riders and watch just how much their front ends dive under braking. Their front ends dive a lot and often. To over simplify the situation to help my point, they setup up their suspension to best deal with grip in the turns and compliance everywhere else. If they set up their bikes to better deal with brake dive, they would be WAY too stiff everywhere else. What do they do to stop excessive brake dive while their suspension is 90% setup for everything BUT braking and too soft during braking because of that fact? They learn how to get into the brakes in a manner that slows and minimizes dive! They get into the rear brake a bit first to squat the rear so the entire bike starts the process lower and minimizes dive but most importantly they EASE into initial braking. The EFFECT is the same as more compression damping without the downside of having too much compression damping for the rest of your ride.

supershaft screwed with this post 11-02-2010 at 01:29 PM
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