RaceTech Cartridge Emulators
- Thread starter debby
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debby said:
for $750 my roadholders are OK....
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$169.99, not $750. I see they're actually called Gold Valve Emulators:
RaceTech page
It looks like installation is non-trivial though
Not sure if it's feasible with Commando forks...
Debby
RaceTech page
It looks like installation is non-trivial though
Not sure if it's feasible with Commando forks...Debby
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debby said:$169.99, not $750. I see they're actually called Gold Valve Emulators:
RaceTech page
It looks like installation is non-trivial though
Debby
oh those ones -thought you meant real replacement cartridges
http://www.cosentinoengineering.com/ind ... ge0019.htm
people use those in laverdas and like them but not to the degree that the are a revolutionary upgrade - not sure about commando though
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Yeah, that looks like a nice kit although a bit pricey.
Actually by Ducati standards that's not bad at all. I just bought a set of Showa fully adjustable forks off ebay for my Ducati GT1000, and by the time I add Gold Valves, new springs, and oil it'll be the about the same price as the Cosentino kit. A lot of people are going for the Lindemann replacement cartridges and they sell for $1200.
Don't know if I need all that for my Norton though. The forks on my 850 aren't working right and I have to pull them all apart and see what's wrong. Seems like a good time to do a little upgrading.
Maybe one of Greg's fork kits would be a better idea. Hey norbsa, got any left?
Debby
Actually by Ducati standards that's not bad at all. I just bought a set of Showa fully adjustable forks off ebay for my Ducati GT1000, and by the time I add Gold Valves, new springs, and oil it'll be the about the same price as the Cosentino kit. A lot of people are going for the Lindemann replacement cartridges and they sell for $1200.
Don't know if I need all that for my Norton though. The forks on my 850 aren't working right and I have to pull them all apart and see what's wrong. Seems like a good time to do a little upgrading.
Maybe one of Greg's fork kits would be a better idea. Hey norbsa, got any left?
Debby
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Yes I have some left. PM me if you like.
Ron L
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Debby,
I have installed the RaceTech emulators in the forks of my cafe racer, unfortunately it is still on the stand awaiting a couple pieces yet to be fabbed and a new paint job, so no road time yet.
The conversion is nicely detailed by Mike Randell on his site here:
http://www.members.shaw.ca/randell/roadholders.html
I have installed the RaceTech emulators in the forks of my cafe racer, unfortunately it is still on the stand awaiting a couple pieces yet to be fabbed and a new paint job, so no road time yet.
The conversion is nicely detailed by Mike Randell on his site here:
http://www.members.shaw.ca/randell/roadholders.html
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I note that the link to my fix is broken on his site so a little hard to come up with any rebuttal comments I don't know what he is quoting. Mike R. has done some important work here to explain how it works.
I have emailed Mike to discuss this a few times as his kits seem to offer the next step in improvements addressing the crude but cheap fix we came up with. I did reveal how my kit works and why I thought it worked in my emails to him and asked him to try it and test it. I got no email after that.
My kit was done by owners for owners and by an account of 100 kits sold over the years it works. This is no high profit kit as any machinist will tell you. With all the emailed help it's a looser for sure. The kit does require that you do some work and thinking on your own though, it is a compromise of lesser evils for sure. The thinking that went into it was revealed as I did it and was openly discussed in this public forum at the time some years ago. Nothings free but with about 100.00 bucks and some work you can do better than the stock set up. JMO though. No scientific research done just seat of the pants testing on about five bikes here in Michigan. These five bikes have all covered about 5000 miles each at least and have been torn down to check that they work as stated. Can anyone make that link work? I invite discussion, always have.
I have emailed Mike to discuss this a few times as his kits seem to offer the next step in improvements addressing the crude but cheap fix we came up with. I did reveal how my kit works and why I thought it worked in my emails to him and asked him to try it and test it. I got no email after that.
My kit was done by owners for owners and by an account of 100 kits sold over the years it works. This is no high profit kit as any machinist will tell you. With all the emailed help it's a looser for sure. The kit does require that you do some work and thinking on your own though, it is a compromise of lesser evils for sure. The thinking that went into it was revealed as I did it and was openly discussed in this public forum at the time some years ago. Nothings free but with about 100.00 bucks and some work you can do better than the stock set up. JMO though. No scientific research done just seat of the pants testing on about five bikes here in Michigan. These five bikes have all covered about 5000 miles each at least and have been torn down to check that they work as stated. Can anyone make that link work? I invite discussion, always have.
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This was the old post from years ago with some thoughts added, things learned along the way. What have you learned?
There were three guys working on this kit. We talked and looked,
and looked some more.
First stage, strip down forks to one
fork stanchion, one slider, one steel bushing with clip to retain,
one high hat bush, one seal and one seal retainer assemble dry
at this point. Check travel, got six inches plus with no dampener tube,
valve, rod or springs.
Ok second stage, add stock dampener tube
with valve supporting rod, tube cap, spring, stock spacer, jam nut.
No fork cap nuts or fluid so when you slide this back and
forth the spring assemblies are coming in and out of the top of
the fork stanchions tops. The travel was four and one half inches.
Note that in this state the springs are loaded against the top of
the dampener tube cap and are trapped by the jam nuts and the
spacer on the other end so the dampener valve is tight up to the cap.
Until the bike is full assembled with the dampener rod jam nut
tight to the fork caps and the weight of the rider is felt the
valve is always going to stay there up against the cap.
The stock length of the rod is limiting the distance the
sliders can move. Do the same test with two inch longer rods and
an extra set of springs for preload and you get back the
six inches of movement. The true limit, the max to be had,
is when the top of the steel bushing hits the bottom of the
high hat bushing.
Now you don't want to ride the bike in this state with
the two bushes tight to one another there's just not enough
support and the front tire will bounce back and forth at
stop lights. So we came up with the two inch longer modification
for the one and one half inches of travel gain so that under
no circumstances could the dampener valve be used
to limit the travel. For this we wanted a fluid stop and not a
one and one half long loose fitting bushing between the two
bushings as used in the the covenant kit.
The springs that come with the kit are from ford tractors and are
the same O.D. and I.D. as Norton and progressive springs.
They start with a two and nine sixteenths free length and have
a bound length of one and nine sixteenths for one inch of travel.
From what we know the stocks springs have one half of an inch to go with
the slider bottomed out, that is the bottom of the stanchion hits
the bottom of the slider. We add one and one half of travel
with longer rods and the extra spring adds one inch of travel and
the old springs had one half inch to go so the springs should
bottom out just as the fork stanchions do.
Now for the fluid control if things were ideal one would have full movement with hydraulic stops at each end that is nice and slow acting right at the
ends of travel.
The best we have come up with so far is using ATF "F" type for fluid and leak proof brand seals. it works on fifty bikes so far with no adjustments needed not that there are no adjustments. I have one bike with stock springs and one with progressive springs and I have to say
that I find the progressive springs better but the stock springs work
well too.
On the center stands these modified bikes don't
lift the wheels of the ground any more but still work for me. Some bikes need a shim welded onto the center stand contact area.
The idea is to get the bike to go down from your weight
at least one and one half inches. Than ride around with four
and one half potential inches for bumps and the
one and one half for pot holes. Norbsa48503
_________________
Some things that make sense learned over time as of 2008.
The dampener caps will be worn on your old bike, and need replacing. They are a big part of how the system works. If you’re using the aluminum dampener rods you should be running bronze caps, they can be had from Clubman Racing. Leak Proof seals and full rubber gators with a little filing of the top hat bushing will provide long lasting non sticking seals it needs to be part of the package with the kit. JMO though.
You are doing your own work here you have to make choices about how the work is done.
In the directions with a kit is a method that works for me and has worked on many bikes.
If you feel the need to omit or change the modifications spelled out you are on your own.
Nothing wrong with that you do the work and thinking with this simple kit anyway.
I encourage you to play with this on your own and please report back to me with your thinking and results. This kit may evolve from your testing. If you would like to do some testing on your own regarding the fluid stops at each end of the travel assemble the whole thing on one side with ATF and without the springs and test away slow and fast by hand.
Beware of fork tubes and bushings that are out of speck they can cause you to do fitting that requires machine work, you may not have a lathe near by. The inside of the bottom of the legs can bind on the taper on the dampener tube check this before assembly. I don’t use a bushing between
the stock ones provided nor a modified longer top bushing to limit travel I rely on the weight of the rider and the oil or ATF F type to allow the bike to sink to the normal ride height .
So you will have issues with brake lines that are too short sometimes, I sell a kit to deal with this it is a one inch longer S.S. brake line and a new one inch taller support bracket so you can use your new upgraded hose. Or just buy a new hose one inch longer hose if you haven’t yet
changed out the brake line. The extra travel seems to make the whole system work better than other alternatives.
I use ATF “F” type and change it often. Twice a season at least.I use Quick fill fork caps made by Bruce Chessel.Bruce can machine your good fork cap bolts or build you stainless ones. I use alloy ones he modified for me.
This is important, if you can renew your fork fluid in ten minuets for a dollar you will do so as you feel the ATF stiffen over the season. If you run expensive synthetic oil and have stock caps your much too likely to put off this 30 minute project to a time that will have you wearing out the parts by grinding them with metal paste. Less is more in this case.
There were three guys working on this kit. We talked and looked,
and looked some more.
First stage, strip down forks to one
fork stanchion, one slider, one steel bushing with clip to retain,
one high hat bush, one seal and one seal retainer assemble dry
at this point. Check travel, got six inches plus with no dampener tube,
valve, rod or springs.
Ok second stage, add stock dampener tube
with valve supporting rod, tube cap, spring, stock spacer, jam nut.
No fork cap nuts or fluid so when you slide this back and
forth the spring assemblies are coming in and out of the top of
the fork stanchions tops. The travel was four and one half inches.
Note that in this state the springs are loaded against the top of
the dampener tube cap and are trapped by the jam nuts and the
spacer on the other end so the dampener valve is tight up to the cap.
Until the bike is full assembled with the dampener rod jam nut
tight to the fork caps and the weight of the rider is felt the
valve is always going to stay there up against the cap.
The stock length of the rod is limiting the distance the
sliders can move. Do the same test with two inch longer rods and
an extra set of springs for preload and you get back the
six inches of movement. The true limit, the max to be had,
is when the top of the steel bushing hits the bottom of the
high hat bushing.
Now you don't want to ride the bike in this state with
the two bushes tight to one another there's just not enough
support and the front tire will bounce back and forth at
stop lights. So we came up with the two inch longer modification
for the one and one half inches of travel gain so that under
no circumstances could the dampener valve be used
to limit the travel. For this we wanted a fluid stop and not a
one and one half long loose fitting bushing between the two
bushings as used in the the covenant kit.
The springs that come with the kit are from ford tractors and are
the same O.D. and I.D. as Norton and progressive springs.
They start with a two and nine sixteenths free length and have
a bound length of one and nine sixteenths for one inch of travel.
From what we know the stocks springs have one half of an inch to go with
the slider bottomed out, that is the bottom of the stanchion hits
the bottom of the slider. We add one and one half of travel
with longer rods and the extra spring adds one inch of travel and
the old springs had one half inch to go so the springs should
bottom out just as the fork stanchions do.
Now for the fluid control if things were ideal one would have full movement with hydraulic stops at each end that is nice and slow acting right at the
ends of travel.
The best we have come up with so far is using ATF "F" type for fluid and leak proof brand seals. it works on fifty bikes so far with no adjustments needed not that there are no adjustments. I have one bike with stock springs and one with progressive springs and I have to say
that I find the progressive springs better but the stock springs work
well too.
On the center stands these modified bikes don't
lift the wheels of the ground any more but still work for me. Some bikes need a shim welded onto the center stand contact area.
The idea is to get the bike to go down from your weight
at least one and one half inches. Than ride around with four
and one half potential inches for bumps and the
one and one half for pot holes. Norbsa48503
_________________
Some things that make sense learned over time as of 2008.
The dampener caps will be worn on your old bike, and need replacing. They are a big part of how the system works. If you’re using the aluminum dampener rods you should be running bronze caps, they can be had from Clubman Racing. Leak Proof seals and full rubber gators with a little filing of the top hat bushing will provide long lasting non sticking seals it needs to be part of the package with the kit. JMO though.
You are doing your own work here you have to make choices about how the work is done.
In the directions with a kit is a method that works for me and has worked on many bikes.
If you feel the need to omit or change the modifications spelled out you are on your own.
Nothing wrong with that you do the work and thinking with this simple kit anyway.
I encourage you to play with this on your own and please report back to me with your thinking and results. This kit may evolve from your testing. If you would like to do some testing on your own regarding the fluid stops at each end of the travel assemble the whole thing on one side with ATF and without the springs and test away slow and fast by hand.
Beware of fork tubes and bushings that are out of speck they can cause you to do fitting that requires machine work, you may not have a lathe near by. The inside of the bottom of the legs can bind on the taper on the dampener tube check this before assembly. I don’t use a bushing between
the stock ones provided nor a modified longer top bushing to limit travel I rely on the weight of the rider and the oil or ATF F type to allow the bike to sink to the normal ride height .
So you will have issues with brake lines that are too short sometimes, I sell a kit to deal with this it is a one inch longer S.S. brake line and a new one inch taller support bracket so you can use your new upgraded hose. Or just buy a new hose one inch longer hose if you haven’t yet
changed out the brake line. The extra travel seems to make the whole system work better than other alternatives.
I use ATF “F” type and change it often. Twice a season at least.I use Quick fill fork caps made by Bruce Chessel.Bruce can machine your good fork cap bolts or build you stainless ones. I use alloy ones he modified for me.
This is important, if you can renew your fork fluid in ten minuets for a dollar you will do so as you feel the ATF stiffen over the season. If you run expensive synthetic oil and have stock caps your much too likely to put off this 30 minute project to a time that will have you wearing out the parts by grinding them with metal paste. Less is more in this case.
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- Messages
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Good info, guys. Ron, that website is exactly the sort of information I was looking for.
I'm more confused than ever though. What he writes about how the forks operate seems to make sense, but it also seems to contradict everything else I've ever read about those forks. I'm not a mechanical engineer so I don't know what to believe :?
My 750 has basically stock forks with Progressive Suspension springs and 20wt fork oil. The damper body holes are in the taper. I don't have problems with them topping out, but they will bottom out hard on a big hit. The "bump stop" doesn't seem to be very effective.
On the 850, I have the Covenant kit installed. I'm using standard springs and 20 wt. fork oil. As part of the kit, the damper body holes in the taper were plugged and new holes drilled above the taper. They still bottom out harshly. I'd say the Covenant kit has made little or no difference. There's something wrong with the forks though, because even little things like entering a driveway at 10 mph will bottom them out really hard. They seem to have little or no compression damping. So I have to take them apart and try to figure out what I did wrong. Good time for upgrades!
The RaceTech kit sounds interesting because the valving should work a lot better than the simple valves in the stock forks. And eliminating the damper rods would make maintenance so much easier. I don't know if that kit would provide any sort of bump stop though. Seems like it would not, meaning the forks may still bottom out hard. I don't know.
Debby
I'm more confused than ever though. What he writes about how the forks operate seems to make sense, but it also seems to contradict everything else I've ever read about those forks. I'm not a mechanical engineer so I don't know what to believe :?
My 750 has basically stock forks with Progressive Suspension springs and 20wt fork oil. The damper body holes are in the taper. I don't have problems with them topping out, but they will bottom out hard on a big hit. The "bump stop" doesn't seem to be very effective.
On the 850, I have the Covenant kit installed. I'm using standard springs and 20 wt. fork oil. As part of the kit, the damper body holes in the taper were plugged and new holes drilled above the taper. They still bottom out harshly. I'd say the Covenant kit has made little or no difference. There's something wrong with the forks though, because even little things like entering a driveway at 10 mph will bottom them out really hard. They seem to have little or no compression damping. So I have to take them apart and try to figure out what I did wrong. Good time for upgrades!
The RaceTech kit sounds interesting because the valving should work a lot better than the simple valves in the stock forks. And eliminating the damper rods would make maintenance so much easier. I don't know if that kit would provide any sort of bump stop though. Seems like it would not, meaning the forks may still bottom out hard. I don't know.
Debby
Debby. Reading through RaceTech's very interesting notes, they suggest that the drillings at the bottom of the original damper tube are probably in the wrong place. For an original Norton Roadholder fork they advise drilling 2 holes in the tube below the taper right at the base of the tube. Block off all other higher holes that may be in the taper or above it.
Their moving clip of the fork then shows the compressed oil being forced up the middle of the damper tube and offering a better type of bump stop.
If you are doing an interim mod, that might be worth a try. Also check how much sag you get just in case your spring are tired.
I think RaceTech's valve mod should be a good move and would eliminate small amplitude patter which the Norton damper cannot control.
Their moving clip of the fork then shows the compressed oil being forced up the middle of the damper tube and offering a better type of bump stop.
If you are doing an interim mod, that might be worth a try. Also check how much sag you get just in case your spring are tired.
I think RaceTech's valve mod should be a good move and would eliminate small amplitude patter which the Norton damper cannot control.
Ron L
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This is the only part of Norbsa's kit I found objectionable. Everything else worked as described. As Greg said, the RaceTech emulators would seem to be the next step to offering better control. I'm anxious to see the results on my cafe racer, just need to find the time to finish it.
scim77, I think you have this backwards. The holes below the taper are blocked and six 5/16th's holes are drilled above the taper. Check the write up and photos on Mike's site.
RonL. If you refer to RaceTech notes by clicking on the highlighted words "Covenant Conversion" and "Bump Stop" they show the arrangement of the original forks and mention that the Covenant conversion advocated drilling above the taper. They also point out that this actually makes for a softer bump stop - exactly opposite to what is desired.
In the lower animated picture they show an original Norton fork but with the earlier Atlas-type hole loation ie. below the taper, which they say gives a firmer bump stop.
The six hole mod above the taper is used when the proper RaceTech valve is fitted.
I was suggesting to Debby that with her standard Norton forks it might be better to modify like the Atlas damper rod.
Have another look at the animated pictures. I think I have understood it correctly. Cheers.
In the lower animated picture they show an original Norton fork but with the earlier Atlas-type hole loation ie. below the taper, which they say gives a firmer bump stop.
The six hole mod above the taper is used when the proper RaceTech valve is fitted.
I was suggesting to Debby that with her standard Norton forks it might be better to modify like the Atlas damper rod.
Have another look at the animated pictures. I think I have understood it correctly. Cheers.
Cash,
The damper cap is a very overlooked maintenance item in fork overhauls, but the clearance largely effects rebound damping. Debby has compression damping issues.
It may be that the damper valve is damaged or that the retaining pin has broken. Curious to see what she finds in the teardown.
My experience with Greg's conversion kit was a nice change. With Progressive springs and 30 wt Bel Ray fork oil, it handled the majority of surface irregularities pretty well.
Since I'm a glutton for punishment, I have since fitted Gold Valves and the shorter Atlas fork tubes (to steepen the front end and quicken the bike's handling a bit). What I can say at this point is that 30wt oil is the wrong weight. The forks are way overdamped. Also, the Progressive springs are too soft with the emulator and Greg's tractor valve springs (part of his kit) can't be used without the damper rod. So, I'm looking in to getting a higher rate spring and I'll be going back to 20wt oil.
Given that Debby is doing the anti-cafe with her mostly stock 850, I'd vote for "more work than its worth." If I stumble on the magic secret formula though, I'll be sure to share.
The damper cap is a very overlooked maintenance item in fork overhauls, but the clearance largely effects rebound damping. Debby has compression damping issues.
It may be that the damper valve is damaged or that the retaining pin has broken. Curious to see what she finds in the teardown.
My experience with Greg's conversion kit was a nice change. With Progressive springs and 30 wt Bel Ray fork oil, it handled the majority of surface irregularities pretty well.
Since I'm a glutton for punishment, I have since fitted Gold Valves and the shorter Atlas fork tubes (to steepen the front end and quicken the bike's handling a bit). What I can say at this point is that 30wt oil is the wrong weight. The forks are way overdamped. Also, the Progressive springs are too soft with the emulator and Greg's tractor valve springs (part of his kit) can't be used without the damper rod. So, I'm looking in to getting a higher rate spring and I'll be going back to 20wt oil.
Given that Debby is doing the anti-cafe with her mostly stock 850, I'd vote for "more work than its worth." If I stumble on the magic secret formula though, I'll be sure to share.
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