Emulators

Originally Posted by 21QUEST

I'm confused here . So does the preload affect the damping or not and If it does how?

Damping is set to slow down the suspension movement for a given travel. If the preload changes, so does the amount of travel. Although this doesnt alter the damping, it does mean that it'll need to be stiffened or softened to work at it's best for a given travel.

Sorry, not worded that well but I hope you understand what I mean

Originally Posted by 21QUEST

Why not and why would the ride become hasher?


Cheers
Ben

Harshness over bumps is characterised by excessive high speed damping. Given that damping rods provide vast amounts of high speed damping, but little low speed damping. You could put an oil thick enough to provide adiquite low speed damping. In practice this would leave the low speed damping so high as to make the ride so harsh it would be unbearable, so you're forced to compramise and accept that front end dive with standard forks will always be there.

I'm pretty sure that's all correct anyway. I'm prepared to be corrected however

[johnnyrod]

Okay I'm gonna attempt to unravel this thread....

The emulators have low-speed comp damping controlled by a small hole in them, high speed by a spring-loaded valve. The preload on this spring (which Blue refers to) controls high-speed damping. Racetech do different emulator springs for this, but that is getting a bit involved.

Rebound damping is still controlled by the damper rod, and really you need 15-20W oil. Some people even suggest brazing up the tiny rebound hole as the blow-by on the damper rod rings is enough, but I don't think this would give you a balanced fork action.

Don't drill the extra comp damping holes as the instructions say, just open up the existing 2 sets of holes - you'll screw the rebound damping at full compression. If this is already done then don't fret it, it hasn't killed me yet.

Blue, with the greatest respect get some softer fork springs or you will never get anywhere - you've admitted the bizzare settings you're on are a workaround which doesn't seem to be making you happy and you're right the fork springs are too stiff.

I'm with sdusk on the settings really, mine are 20W oil (15W was too litle rebound), either 3 or 4 turns of emulator preload (2 turns was good but it is worth trying it out), sag set as it should be (20-25mm with rider), stock air gap. Mine does slap just a little if you really go bananas but it has a fantastic feel and does what I want it to. I ended up with Progressive springs, linear are supposed to be better, but as a note in case you do the same, they are pretty sensitive to getting the preload right, I only add 3 turns of the adjuster at the front when I add a pillion.

Does any of that help? If anyone's around here or at Rockingham at the end of the month you're welcome to give the axe a try.

Yeah, I realised from the start that I was oversprung, but the high and low speed damping was also way too much i.e. it was very hard to get initial movement, and was returning way too slowly. I don’t think where the bike has been set with max preload (not adjustable (without a hacksaw anyway! )) it was helping the highspeed absorption either.

I tried using thinner oil (15w from 20w) and 2 turns of emulator preload. It was still way too stiff and slow for my liking, especially on the highspeed.

As I am tight, I didn’t want to fork out (no pun intended ) for new springs, that coupled with the fact I felt I was still overdamped (even for a heavy spring) I went way down on the oil, and backed the emulator preload right off (to try and improve movement with high speed further).

Bearing in mind how overdamped my forks seemed with 20w oil and 85 springs, I seriously reckon that with some 80, or even 75 springs that 20w oil will be over damped? I know I am a little underdamped with the 7.5w, but this does give me some compliancy, to be honest it works ok, the only time it is a problem is if I get a series of big bumps close together (then the front, not particularly surprisingly, starts pogoing)..

Oh and I now have a track SV too I intend to swap the stock forks from that and use on my road bike and put these emulator forks in the track bike. As I now have justification to spend a bit of cash (i.e. I am going to use it on track and NEED the suspension to work), I will go for new springs, but I tell you what, I am going to start off with 10w oil and see how I get on!!

Originally Posted by johnnyrod

Don't drill the extra comp damping holes as the instructions say, just open up the existing 2 sets of holes - you'll screw the rebound damping at full compression. If this is already done then don't fret it, it hasn't killed me yet.

Is this a generally accepted deviation from the installation instructions?

I ask because I have some emulators sitting in a box waiting to be fitted (EDIT: to a curvy) and would like to avoid doing anything which is going to have a detrimental effect when I eventually get round to fitting them...

Thanks

Hmm, that might depend on whether you have a curvy or pointy. For the pointy the holes are already within a 1/32" of the size that they are supposed to be drilled to. If you didn't drill the extra set, then you wouldn't be changing the damping rod at all!

[johnnyrod]

Yeah, just for a curvy.

Blue, are you sure the forks weren't twisted? Sounds like a lot of sticktion. It does sound like something funny is going in, I would suggest taking the emulators out of the crap forks and starting again with the stock forks, or at least strip them and find out what has been done to your rods. So you're too tight to spend £70 or whatever on springs but have a track bike? I'd definitely get the preload adjusters, this could jsut be adding to your problems.

Originally Posted by johnnyrod

Yeah, just for a curvy.

Blue, are you sure the forks weren't twisted? Sounds like a lot of sticktion. It does sound like something funny is going in, I would suggest taking the emulators out of the crap forks and starting again with the stock forks, or at least strip them and find out what has been done to your rods. So you're too tight to spend £70 or whatever on springs but have a track bike? I'd definitely get the preload adjusters, this could jsut be adding to your problems.

Lol, its all about justification … I can justify £70 on a set of springs for a track bike … but I can’t justify it for a roadbike … I have to draw the lines on expenditure somewhere!!

It did cross my mind about the forks/yokes being bent, but whenever I take the wheel out or slide the forks out, they come out without any problems. Normally if something is bent, things tend to ‘ping’ a bit as you strip. I suppose I should ‘roll’ them to see if they appear straight.