View Full Version : Racetech emulators
I have inherited a set of racetech emulators and springs from previous owner. The front shocks are noticeably clunky/noisy and spongy. I have calculated that I need 0.85 kg springs from racetech website (my weight is 87kg) but the ones I have are 1.0kg which is a bit too stiff? I presume it will be an improvement over stock anyway so I should just get on and fit them or would it be uncomfortable/unsafe. Would I be better off bunging them on ebay or selling to somebody on here with a bigger beer gut than me?
northwind
14-10-07, 05:41 PM
I'd not fit those springs if I was you, if a job's worth doing it's worth doing right IMO... And you should be able to sell them easily enough. You'd probably be happier taking a loop off the stock springs than using those ones, they really are pretty hard for you.
Agree with Northy. We have 0.95 springs but we are two-up all the time with a combined weight a lot more than yours:D
DarrenSV650S
14-10-07, 05:58 PM
I have calculated that I need 0.85 kg springs from racetech website
Where do you do that on their website?
chazzyb
14-10-07, 06:25 PM
I calculated I needed .85kg springs also (fat sod, me). PDQ however recommended that I go with .80kg and use 15W oil rather than 20W. I fitted it all *yesterday* (springs and emulators). First impressions didn't give that me that "WOW, what a difference" I'd been hoping for. However, I've been out today with my IAM group and I reckon the high-speed behaviour is much better. Now then, what's the shock of choice... ;-)
http://www.racetech.com/evalving/menu/searchstreet.asp (http://www.racetech.com/evalving/SpringRateCalculation/dirtspring.asp?brand=Suzuki&yr=03-07&ml=SV650S&formuse=form1&SpringType=Fork)
Link for the calculator above. I'll probably sell them on then, so unless I put on a lot of weight in next few days they will be available to anybody who is interested?
DarrenSV650S
14-10-07, 07:43 PM
http://www.racetech.com/evalving/SpringRateCalculation/dirtspring.asp?brand=Suzuki&yr=03-07&ml=SV650S&formuse=form1&SpringType=Fork
Link for the calculator above. I'll probably sell them on then, so unless I put on a lot of weight in next few days they will be available to anybody who is interested?
This is what it said:
Rider Weight: 147.5 lbs.
Recommended Spring Rate: n/a kg/mm (use closest available)
Stock Fork Spring Rate (measured): kg/mm (stock)
No Spring Series available for your bike.
Please call technical support (951)279-6655 for help.
21QUEST
14-10-07, 07:50 PM
This is what it said:
Rider Weight: 147.5 lbs.
Recommended Spring Rate: n/a kg/mm (use closest available)
Stock Fork Spring Rate (measured): kg/mm (stock)
No Spring Series available for your bike.
Please call technical support (951)279-6655 for help.
Here you go ;)
http://www.racetech.com/evalving/SpringRateCalculation/dirtspring.asp?brand=Suzuki&yr=03-07&ml=SV650S&formuse=form1&SpringType=Fork
Use this link http://www.racetech.com/evalving/menu/searchstreet.asp
Ben
Blue_SV650S
14-10-07, 07:55 PM
I calculated I needed .85kg springs also (fat sod, me). PDQ however recommended that I go with .80kg and use 15W oil rather than 20W. I fitted it all *yesterday* (springs and emulators). First impressions didn't give that me that "WOW, what a difference" I'd been hoping for. However, I've been out today with my IAM group and I reckon the high-speed behaviour is much better. Now then, what's the shock of choice... ;-)
I'd go with 80s too ... the 100s will be silly ...
Can I just fit the damping cartridges and use original springs? Would this get rid of the clunking/ improve anything? If so is 20w oil correct?
Blue_SV650S
14-10-07, 08:02 PM
Can I just fit the damping cartridges and use original springs? Would this get rid of the clunking/ improve anything? If so is 20w oil correct?
Not sure it'd get rid of the clunking, but yes you can fit the emulators with stock springs. I should imagine you would be wanting 10w oil ... I only say that as I have 15w with my 80s so assume 20w would be way too much for stock (~70?) ...
Ok thanks. Will probably just replace the dampers/oil.
petevtwin650
15-10-07, 10:30 AM
Ok thanks. Will probably just replace the dampers/oil.
You do realise that you have to fully dismantle the forks to properly install the emulators?
johnnyrod
18-10-07, 11:41 AM
Nah you don't need to do the damper rod drilling, I know it's in the instructions but not necessary. Just the emulators will help with the control over the damping (I would use 15W oil and 3-4 turns of EMULATOR preload, once you've found a 19/256th inch or whatever stupid Imperial size Allen bolt is used), but the springs are too soft for anyone, I went this route and replaced the springs second. Whatever you do, make sure you set the sag right.
chazzyb
18-10-07, 12:02 PM
Nah you don't need to do the damper rod drilling, I know it's in the instructions but not necessary. Just the emulators will help with the control over the damping (I would use 15W oil and 3-4 turns of EMULATOR preload, once you've found a 19/256th inch or whatever stupid Imperial size Allen bolt is used), but the springs are too soft for anyone, I went this route and replaced the springs second. Whatever you do, make sure you set the sag right.
I'm not sure I agree with the "don't need to drill the damper"' bit. The reason I installed emulators was because the high-speed/big bump damping as standard with 15W oil (used for the rebound damping) was much too harsh. Unless the standard compression damping is defeated by the addition of holes, the emulators won't be able to do very much, except for the low speed compression damping.
Is there an idiots guide anywhere on the net. Got a haynes manual and the kit instructions but they are not a lot of help. I am usually fairly handy with the spanners, but am really not sure of the steps involved. Have taken the front wheel off this week to fit a new tyre so removing the shocks isnt too scary. Do I need any special tools/spring compressors etc. Just been to buy a pint of 10w synthetic stuff today.
chazzyb
18-10-07, 09:07 PM
Is there an idiots guide anywhere on the net. ... Just been to buy a pint of 10w synthetic stuff today.
If you're going to install the emulators, I really do suggest you do as Ractech suggest. This does involve adding a couple of holes to the damper tubes and 15W, if not 20W fork oil. Racetech specify 20W, but PDQ, the UK agent suggested 15W to me for road use. 15W fork oil in my standard SV forks was just too harsh on the compression damping. The purpose of the emulators is to replace the stnadrd compression damping. That isn't going to happen if you don't add the holes to the damper tube.
I'm sure someone has posted a 'how to' on here before about installation. I could scan the Racetch general instructions and e-mail them if you want? PM me if you do. There's certain SV-specific technique involving a broom handle for getting the damper tube retaining bolt undone. ;) That won't be in the Racetech instructions, but I did read it here, somewhere.
Robw#70
18-10-07, 10:06 PM
Nah you don't need to do the damper rod drilling, I know it's in the instructions but not necessary. Just the emulators will help with the control over the damping (I would use 15W oil and 3-4 turns of EMULATOR preload, once you've found a 19/256th inch or whatever stupid Imperial size Allen bolt is used), but the springs are too soft for anyone, I went this route and replaced the springs second. Whatever you do, make sure you set the sag right.
EEEK 3-4 turns on emulator and no compression holes:smt068
The purpose of the emulators is to replace the stnadrd compression damping. That isn't going to happen if you don't add the holes to the damper tube.
if you do add holes it will mess up rebound.better way is to enlarge existing holes.10-11mm works.while there you may as well close rebound hole.
.85 springs with 15W oil should work for natcar.
chazzyb
19-10-07, 10:24 AM
if you do add holes it will mess up rebound.better way is to enlarge existing holes.10-11mm works.while there you may as well close rebound hole.
As far as I can see, the holes in the SV damper tube deal with compression damping, not rebound. Larger holes are going to risk weakening the tubes, aren't they? All you're trying to achieve by adding holes (from 4 to 6), is increase the area that the oil has to flow through. Making the existing holes bigger will have the same effect (don't know about the area) but will possibly risk weakening the tubes.
As far as I can see, rebound is dealt with by a much smaller volume of fluid being driven into the slider cavity through the gap between the stanchion and the damper tube - there is a valve-type arrangement inside the bottom of the stanchion that the damper passes through.
Frankly, if Racetech say do it one way, why do it another? I'm sure they know what they're doing.
Frankly, if Racetech say do it one way, why do it another? I'm sure they know what they're doing.
they use generic instruction from day they made emulator(20 or so years ago).sv fork tubes have seal in such place that will slide over extra hole you drill at which point that hole becomes rebound hole.
it only comes in to play at last part of travel when forks are compressed.
larger holes don't weaken rods since all pressure is from top.
chazzyb
19-10-07, 06:44 PM
Fluid may well go back through the large holes in the damper on rebound (I'm sure it does, as the emulator has a second weak spring flap valve to allow it to), but I'm damned sure they are not responsible for the rebound damping. As I suggested earlier, I think the rebound damping is done by fluid being forved out of the bottom of the stanchion, from the space between the tube and the stanchion around it. The fluid going back down the damper tube is simply returning to the main slider reservoir and not providing any rebound damping to speak of, because the surface area of the aperture at the base of the stanchion which has the tube moving in it, is MUCH smaller.
ok,obviously you understand there is rebound chamber for oil.when tube goes up oil flows through small rebound hole near top of damper.
now imagine tube at fully compressed position.that chamber has 2 holes now,small one at top and big one you drilled down at bottom.tube passed over big one at full compression,on the way up this hole is rebound hole for as long it takes tube to get over it.once over it you are back at small hole on top only.
higher up on damper rod you drill this additional hole longer you will be with 0 rebound.
Robw#70
19-10-07, 07:08 PM
they use generic instruction from day they made emulator(20 or so years ago).sv fork tubes have seal in such place that will slide over extra hole you drill at which point that hole becomes rebound hole.
it only comes in to play at last part of travel when forks are compressed.
larger holes don't weaken rods since all pressure is from top.
Having racetech'd 30+ sv's for both road and racing (incl racing on them myself), fitting the emulators as per racetech instructions, this has never been a problem.
The holes bypass the rebound on the very last bit of travel (less than 10mm before bottoming) so only occurs with extreme braking and because the distance is so small the rebound is controlled before it is an issue.
It is certainly not an issue on the road and i have never come across a problem on track.
Being tech support for racetech in the uk i have spoken to alot of dealers using racetech products and the problem has never come up.
I can see why there could be an issue, As traxxion state in engineering/technical terms there are other ways round it.
But like alot of things on a production bike you are always limited to the capabilities of the chassis.
I have tried both ways and just prefer to do it the recommended way, esp as emulators are still sold with these instructions, i cant tell someone who calls to do the opposite to what they have in front of them.
The holes bypass the rebound on the very last bit of travel (less than 10mm before bottoming) so only occurs with extreme braking and because the distance is so small the rebound is controlled before it is an issue.
if you do use full travel you will have this happen in worst possible time.like hard on brakes before corner,especially bumpy ones.your forks will chatter.your forks will move between bottom and 0 rebound until you release brake and transfer weight to rear.
why have this if you can simply enlarge existing holes and have no issue.
you are correct,less of issue on road because most dont use suspension fully.however,hitting large bumps at speed does not make it feel to comfortable.
there are also people out there that will follow all kind instructions,some drill holes higher than others,some take hydraulic lock piece out,some drill holes in hydraulic lock piece.....etc.
Robw#70
19-10-07, 07:45 PM
Yes but the problem is not a problem, like i said i have fitted them like that to ALOT of bikes since 2000, which have won races and championships, Im also pretty competent on a track myself and it has NEVER been a problem, for me or any rider i have done work for.
maybe not to you,for me it is problem that needs to be fixed.
I rode bike with this set up and it was chattering.I also know of number of others with same problem.problem was fixed with new rods.
even if it is 1 out of 100 it is still problem to me.
ps.your resume does not mean problem is none existent.how fast you go has nothing to do with it.
Robw#70
19-10-07, 08:28 PM
maybe not to you,for me it is problem that needs to be fixed.
I rode bike with this set up and it was chattering.I also know of number of others with same problem.problem was fixed with new rods.
even if it is 1 out of 100 it is still problem to me.
ps.your resume does not mean problem is none existent.how fast you go has nothing to do with it.
But the chatter can be because of a poor setup.....
To put some perspective on it, we have over 2500 trade customers that we supply racetech products to, I am the person that they talk to when there is a problem/query on racetech installation/setup and this problem has never come up.
Add to that I have been racing for a number of years and also offer trackside suspension service and in the uk we have a class that is 99% sv's and a good number of these bikes i have setup for riders of varying abilities, weights and speeds.
THIS HAS NEVER BEEN AN ISSUE, even if it was as you say 1 in 100 then i would have come across it?
But hey what do I know?!
But the chatter can be because of a poor setup.....
yes,it can.it can also be luck of rebound :)
no point to argue any more.
all I am saying to those that do it yourself,be careful what you drilling and where you drilling.there is a lot of misinformation out there.
there was guy on svrider who said more holes are better and you should drill them all around rod :lol:
ps.I have pile of rods drilled by race tech specs,people doing it them self.location of holes very 5mm up/down.those that are little higher on rod have 15mm of travel wasted(that is more than 10% of travel).yes,you can change oil level,spring rate,preload...and never use that part but than I see no point of setup.
maybe not to you,for me it is problem that needs to be fixed.
I rode bike with this set up and it was chattering.I also know of number of others with same problem.problem was fixed with new rods.
even if it is 1 out of 100 it is still problem to me.
ps.your resume does not mean problem is none existent.how fast you go has nothing to do with it.
If this was happening to my bike, I'd be looking at the way I rode it or the setup.
Having seen Rob race, and witnessed quite a few of his previous 'suspension jobs' circulating the race tracks of Great Britain, he knows what he's talking about - it would be a foolish man or an engineering genius who questions his word.
If this was happening to my bike, I'd be looking at the way I rode it or the setup.
Having seen Rob race, and witnessed quite a few of his previous 'suspension jobs' circulating the race tracks of Great Britain, he knows what he's talking about - it would be a foolish man or an engineering genius who questions his word.
so,if I tell you I am faster and better racer than him and guys on my suspension circulate more tracks would that mean I know more than him?
we are not talking about Rob here.if he sets it up right and have no problem with set up it does not mean problem does not exist.it just means he has not run in to problem,or experience it,or recognize it,or he did but changed settings to get around it.
no need to turn this in to Rob against me because that is not what it is.all I am saying there is flaw in instructions.you are free to do it any way you like it.
I still did not get answer why drilling holes bigger is not better or problem.
chazzyb
22-10-07, 08:19 AM
I still did not get answer why drilling holes bigger is not better or problem.
Why? We thought you knew bigger holes are better already; you said so!:p
Robw#70
22-10-07, 10:39 AM
As long as the compression is eliminated then you can do it either way.
I havn't done the maths but i dont think you get the same overall hole size by enlarging the existing holes to 11mm
northwind
22-10-07, 11:50 AM
Zadar knows stuff. That's all I'm saying. The internet is a big place you know ;)
I fitted my emulators as per instructions, should I be worried?
Mind you, I have no intention of racing...
yorkie_chris
22-10-07, 02:23 PM
As long as the compression is eliminated then you can do it either way.
I havn't done the maths but i dont think you get the same overall hole size by enlarging the existing holes to 11mm
From somebody who knows little of suspension but a bit about fluid mechanics:
The area is not the be all and end all of how much resistance there is to flow, the fluid is quite thick (viscous), so will be affected by the boundaries of the hole, i.e a smaller hole will not flow proportionally less than a big one, the effect will be greater than this, especially as the speed increases. (speed of fluid flow through the hole that is)
chazzyb
22-10-07, 04:32 PM
As long as the compression is eliminated then you can do it either way.
I havn't done the maths but i dont think you get the same overall hole size by enlarging the existing holes to 11mm
I trawled old, deep suppressed memories and after a bit of work with a calculator, have to admit that 4 x 10mm holes (stock holes are 8mm) have slightly more surface area than 6 x 8mm.
But of course, 10 mm holes are going to seriously weaken the tube so much it will collapse the first time the forks compress. :-dd
yorkie_chris
22-10-07, 04:50 PM
But oil behaves in a more complex way then that, the overall effect will be different
But oil behaves in a more complex way then that, the overall effect will be different
all you doing is making emulator more restricted than stock holes.
As long as the compression is eliminated then you can do it either way.
in your previous post you agree there is 10mm of travel with 0 rebound.
do you set up fork to not use this part of travel or you just ignore it?is that what you mean by 'compression is eliminated'?
Robw#70
22-10-07, 06:03 PM
sorry replied on my phone so didnt word it well.
by eliminating compression i meant that the compression part of the damper rod was eliminated.
I still setup to use full travel as this last bit of travel is also when the fork is in the bottom out cup, where any level of rebound control is over powered by the bottom out cup (hydraulic lock).
The main working area of travel is not effected by the upper holes and the hardest of cornering will use 3/4 travel (again not effected by the upper holes).
Hard braking whilst upright is when the forks will be compressed enough to be over the upper holes, as braking hard enough to get the forks in this area whilst tipping in would overcome the grip of the tyre (unless wrong springs/airgap etc)
I dont profess to be any kind of engineering genius, its just my interpretation of it from working with racetech products on a daily basis and being in contact with a large number of dealers and customers, getting feedback and offering technical support, Which is more than your average motorcyclist that would be fitting the stuff.
Hard braking whilst upright is when the forks will be compressed enough to be over the upper holes, as braking hard enough to get the forks in this area whilst tipping in would overcome the grip of the tyre (unless wrong springs/airgap etc)
it can also be that this holes will make tire lose grip.
forks will chatter when they get at point where they are between hydraulic lock and 0 rebound.
some people will confuse this with bottoming forks and try to tune it out by adding oil or preload.in which case they just make bike ride higher in stroke and use less travel.
Robw#70
22-10-07, 06:31 PM
I meant more that the amount of force req to compress the forks to this point is more than the grip available from the side of a tyre, but i agree that lack of rebound would make the tyre breakfree early.
I think its time to agree to disagree, having ridden nearly all of the uk circuits and supported a large number of riders on sv's I have not had this problem.
Im suprised there's not an alternative to the emulator by now (without going to cartridges), Gubilini do a sort of plug type effort, but its no more than smaller holes, The only one that seems better is the Matris kit which uses a proper shim stack, but only available for injected bikes.
there is one company in Australia making valve similar to emulators but using shim stock.
problem I have with extra holes is that this kit is sold as do it yourself.
if you look at this pic you will see how people drill holes in different places.
bottom is stock rod,top one has holes drilled in between stock ones(which I would still take over those drilled higher up like 2 rods in middle).
2 rods in middle are set and one has holes couple mm higher than other.
second pic will show you those extra holes in relation to fork fully compressed.
first pic did not upload.
http://i141.photobucket.com/albums/r71/twf164/dampingrod003.jpg
scroll down this page
http://www.promecha.com.au/roadbike_products.htm#provalve
Robw#70
22-10-07, 07:07 PM
problem I have with extra holes is that this kit is sold as do it yourself.
if you look at this pic you will see how people drill holes in different places.
bottom is stock rod,top one has holes drilled in between stock ones(which I would still take over those drilled higher up like 2 rods in middle).
2 rods in middle are set and one has holes couple mm higher than other.
second pic will show you those extra holes in relation to fork fully compressed.
But when that shuttle is fitted to the stanchion and the damper rod is sat on the bottom-out cup it will be at least 5mm higher and with the correct airgap (which again will be fully compressed at this point) and the bottom out cup working I cant see that the compression hole being uncovered can have a great effect (if any).
Is that an injected shuttle on a carby damper rod btw?
I agree about people fitting things themselves, I re-did a set of VFR800 forks the other week where they had fitted compression and rebound valves, but they had managed to glue all the shims together on all the valves, but before getting this far managed to bend most of the shims on the compression valve when fitting the bolts, then spent the next couple of weeks trying every type of oil trying to get some damping :rolleyes:
Robw#70
22-10-07, 07:30 PM
scroll down this page
http://www.promecha.com.au/roadbike_products.htm#provalve
This is the Matris kit, it uses a proper rebound and compression shim stack with 2.5/5wt oil so no heat problems:cool:
They retail at £300 so £100 more than emulators/springs but half the price of a cheap(ish) cartridge kit.
what is shuttle?
that piece around rod is bottom of fork tube,just taken out.
both pieces are from same injected bike.they dont interchange between bikes.99-02 rod is bigger diameter.
dont forget some drill hole or remove bottom out cone.
personally I remove them because I want all travel I can get.for same reason I dont like to compensate with air gap.I dont like any progression.that is reason we put linear springs in there,so there is no progression.
This is the Matris kit, it uses a proper rebound and compression shim stack with 2.5/5wt oil so no heat problems:cool:
They retail at £300 so £100 more than emulators/springs but half the price of a cheap(ish) cartridge kit.
provalve damping kit is matris?
I saw picture of matris that looks different than this valve.
you can buy F3 catridge pretty cheap.you can also adapt many different catridges.AK20 would be most expensive one but you get what you pay for.
there is plenty of options,emulator is still best option for average Joe.
Thanks for all the advice although a fair bit has gone over my head and I havent started looking at the racetech instructions. I have found some .85 springs and will swap the oil for 15w. Will let you know how I get on.
Robw#70
22-10-07, 08:09 PM
provalve damping kit is matris?
I saw picture of matris that looks different than this valve.
you can buy F3 catridge pretty cheap.you can also adapt many different catridges.AK20 would be most expensive one but you get what you pay for.
there is plenty of options,emulator is still best option for average Joe.
No sorry Pro-valve and Matris are Different companies.
The 'Shuttle' is the bit in your picture at the bottom of the damper rod (the piece holding the seal etc in the bottom of fork stanchion), on some replacement fork tubes available here this piece needs swapping.
I only asked about the pic as I thought the 'shuttle' was out of an injected leg wheras the second pic were all carby rods.
There's been some pretty frightening cartridge conversions done here, but luckily the worst culprit for messing them up are no longer trading, good ideas just badly executed:smt093
Robw#70
22-10-07, 08:12 PM
Thanks for all the advice although a fair bit has gone over my head and I havent started looking at the racetech instructions. I have found some .85 springs and will swap the oil for 15w. Will let you know how I get on.
Sorry for the hijack, bet you wished you never asked:pale:
Any problems just ask, i'll pm my #
The 'Shuttle' is the bit in your picture at the bottom of the damper rod (the piece holding the seal etc in the bottom of fork stanchion), on some replacement fork tubes available here this piece needs swapping.
I only asked about the pic as I thought the 'shuttle' was out of an injected leg wheras the second pic were all carby rods.
shuttle goes out for catridge install.
pic does show carby rods,few I have around.however,like I said they dont interchange.you can also tell by color of seal(green).
btw.there is guy selling some pieces to install gsxr catridge but at expense of losing 20mm or so of travel.according to him that is fine :)
Fitted now, but not been out yet, feels a bit more positive at the front. I have about 30mm of sag with me onboard after cutting 10mm of the spacers- is this right?
Also, should I try to eliminate the knocking on the head bearings by nipping it up a bit or will this just wear them out quicker?
Luckypants
30-10-07, 07:12 PM
Fitted now, but not been out yet, feels a bit more positive at the front. I have about 30mm of sag with me onboard after cutting 10mm of the spacers- is this right?
30MM might be too little, depends on how you ride really. I had 35mm which allowed more travel to cope with pot holes on the bumpy roads round here. You can dial in more / less sag with the pre-load adjusters on your pointy.
Ok the adjusters are mid point so I should be able to back them off to 35mm. We have plenty of potholes around here too.
johnnyrod
31-10-07, 12:36 PM
Leave it at 30mm and try it first. If your head bearings are knocking then they're scrap already, you can tighten them up but all that will happen is you get the awful (and dangerous) self-centring feel. Are you sure it's not the fork internals clunking? They do that a lot, it doesn't mean anything.
PS when you go for your first ride on the emulators you'll probably think "what's different?" Take it on something really challenging like chossy B-roads and you'll find out, it'll glide over what used to tie it in knots.
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