Emulators
 

Right. I've decided I'm going to buy some Racetech emulators. The firmer springs and thicker oil have improved things a lot over stock but the high speed damping is far too hard.

Before I go straight to PDQ for the emulators are there any sv650.org recommended retails? Anyone who is particularly helpful when it comes to setup etc.

P.

Re: Emulators
 

I bought mine from the US, and ended up paying about £160 for oil, springs and emulators. I don't know how they compare here.

As for setup, it is down to personal preference, though the instructions will give you recommended settings for road or race setups, so start there and adjust accordingly. robw#70 knows a lot about these, so maybe drop him a PM or he may be along shortly anyway. :D

Re: Emulators
 

Didn't you get stung for inport tax?

P.

Re: Emulators
 

No, I had it sent to my sister and she then packaged it all up with a note saying 'Happy Birthday - I hope this was what you wanted!'

Ringding, I started off with 15w oil and 2 turns of emulator preload - the result was harsh with not enough rebound damping. After talking to the Racetech folk I changed it to 20w oil and 1.5 turns of emulator preload and it is much better - firm, stable and not harsh at all.

Emulators from PDQ are around the £110 mark I believe. Not sure if they could help with setup (fitting is easy), but there are a number of people (inc. me) with the emulators who can give you setup tips.

Thanks for the tips guys. I guess I'll go ahead and buy them and see what the setup instructions are like.

I'll keep you posted!

What weight spring are you using??? I have 85s, ended up taking all the preload off the emulator and using 7.5w oil to get some sort of movement in the forks!!!

With 20w oil it was way way to firm!

When quoting spring weight, its probably usefull to also mention your kitted up weight otherwise people wont know what to go for. I am abt 70 kitted and .75 is recomended for me by racetech.

I run 20wt oil too, 15wt was far too soft.

You did remember to drill the holes in the damping rods... didn't you?

Same here - using 20wt on a K3 with 2 turns. I really like the feel of this - I would have thought 7.5 would have been well under-damped?

Good point. I did the same using the tool on the Racetech site and came out with a rate of .77 for me (I'm 70-75kg kitted up). I think this is pretty close to standard spring rate.

However, I recently did a halfway house fix of fitting new KTech springs and changing the oil to 15W. I was told KTech only do one rate for the SV (0.85) and so am using those. This set up (0.85 and 15W oil) is "better" than stock as I have a lot more feedback from the front, especially in slow corners, but on bumpy roads it can be a bit of a handfull. I think I've gone from one extreme, squashy and mushy, to too firm. Hence the desire for the emulators and a temptation to go back to the standard springs.

Good point.

I am about 80kg nekkid, and about 100kg kitted (I have heavy leathers and carry lots of stuff in a rucksack).

I didn't do any of it (originally), it was professionaly done.

I use the .80 springs as recommended for my weight by the Racetech site. I found the RaceTech recommendation of two turns of emulator preload (controls the compression damping with the emulators) to be too harsh. 1.5 turns is just right for me, and others have said that 1.5 to 1.75 turns is good for them. Two turns may be okay for heavier riders I suppose. Using the 20w oil was necessary to give the front end enough rebound damping (oil viscosity controls the rebound damping mostly with the emulators). when I was using the 15w oil there was just nowhere near enough rebound damping for the spring. Getting the rebound damping right really adds to the solid/planted feel that most riders strive for.

My thoughts were that the preload controls the highspeed compression damping, the oil viscosity/valve itself controlling the lowspeed compression damping. Then just the viscosity setting the rebound.

My front end was solid, it was hard to get moving in particular. Somone from here (Rob#70??) recommended that I backed off the preload to 2 turns and put 15w oil in (had 20w).

I still felt this was way to harsh, so went for the 7.5w and zero preload option as I was still miles off what I wanted. I am indeed still oversprung for my liking, but the suspension is much more compliant now.

It’s the high speed damping (too much of it) that was the worst!! i don't have an ideal setup now, but something I can live with.

Note that the Traxxion spring rate graph is slightly diffrent from the Race Tech one. From what i can see is that where Race Tech have a Supersport(Track) & Sports Bike graph the Traxxion is only 1 and shows much higher springrates that are more comparable with the Race Tech Supersport (Track) graph which is way too hard for the road.

This is why the Traxxion rates that peeps are showing are way higher than the Race Tech specs for the road IMO.

With respect, are you sure you're using the correct terms?

While it would be an inacuracy to say that altering preload doesnt influence how damping responds (because it does, and this is why you should set up your preload first) you shouldnt be altering preload in an effort to change your damping settings, because it won't.

Damping rods aren't ideal because the nature of forcing oil though a fixed apature. I wont bore you with the details but this setup results in alot of high speed damping (harsh over bumps) with very little low speed damping (lots of fork dive under breaking for example).

Simply bunging in heavier oil will just make the ride harsher without really addressing the fork dive problem properly. This is why we install emulators, because they provide the low speed damping (emulators are only designed to affect compression damping, I may add) required.

As for the problem of the harsh ride you're encountering, I have a theory on that. When installing emulators, the damping effect of the damping rod needs to be reduced. This is achieved by removing the rods and drilling additional holes in them so they become less effective and allow the emulator to take control. It sounds to me like it's quite possible that this wasnt done.

Four things immediately come to mind if it felt absolutely solid/unmoveable – either the spring rate is too high (your spring is too hard as you said, but not *that* much too hard), your damping rod wasn’t drilled out correctly when the emulators were installed, your oil level is too high (worth a check with the RaceTech folk) or the preload spacer is too long. Supplied with the RaceTech springs are preload spacers that you have to cut down to the right length to give you the correct static race sag (RaceTech call it "Static Race Sag" and Ohlins call it "Ride Height", and other folk call it all sorts of things). I had to cut the spacers down 5 times before they were the correct length to enable me to use the bikes preload adjuster screw to fine tune the last bit. If the previous owner was much heavier than you then there is a chance that the bikes preload adjuster will just not give you enough adjustability, and you will have to go for the hacksaw instead.

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





Why not and why would the ride become hasher?


Cheers
Ben :wink:

Ah … I can see how I have confused my meaning … I was talking about the preload on the emulator, not the main fork spring. i.e. I wound my emulator spring from 2 turns to zero turns, therefore reducing the ‘emulator preload’ if you will. That is the preload I was meaning.

As for the actual preload on the main spring i.e. the resulting ‘sag’ setting. I measured that, can’t remember the exact value, but at the time I thought it was on the higher side of things i.e. it was near the maximum recommended ‘ballpark’ preload, but it was within ballpark.

As for the drillings, I’d have to take apart again to check, but it was done professionally, so unless it was a Friday afternoon job, I doubt that has not been done/been overlooked?

Oh and I have set the fork oil with a 130mm airgap (forks compressed, emulator in, no springs).

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 :o

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 :)

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! :lol:)) 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 :lol:) 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!!

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!

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!! :lol:

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.