ReX
TY 4 Stroke God
Here is the multi-stage valve stack I am using on my main shock:
16x210 Spacer (to make sure the nut doesn't bottom on threads)
16x110 Spacer
26x150 End of first rebound stage
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 First rebound stage
2 slit piston bypass ports
30x200 First compression stage
30x200 End of first compression stage
18x150 Space before second compression stage kicks in .
30x200 Second compression stage
30x250 .
30x250 .
30x250 .
26x150 End of second compression stage
18x110 Space before third compression stage kicks in
16x110 Space before third compression stage kicks in
Hard stop (large thick washer)
As you can see my first stage is only 2x 0.200 mm thick valves, when stock the first stage was an incredible 12x 0.200 mm thick valves. Just imagine how much smoother my sled rides over small bumps. My second stage, with 0.150 mm open already, ends up being softer than the stock 1st stage also. My 3rd stage is fairly aggressive for this sled and it is very difficult to bottom out. If you want a little softer final stage, you could use a 16x150 3rd stage spacer instead of the 16x110. Of course my center shock is definitely contributing to the damping also, but the main shock does more of the work on big bumps.
FYI, Mike Carver's center shock setup has a soft 1st and 2nd stage compared to stock combined with a fairly aggressive 3rd stage too. It works well.
Yesterday I rode a stretch of trail with 1-2 foot moguls for about 2 miles. It bottomed out twice when I totally missed some of the bigger doubles (jumping from one mogul and hitting the up-slope on another) and when I put my hands on the shocks to see how hot they were, both were comfortably warm and free of snow (I had been riding hard on rough trails before that very rough stretch for about 2 hours). Stock, the non-functional center shock was always covered in snow and ice and the sled would have been bottoming and kicking and bucking everywhere on that trail. Stock I would not have been able to travel that trail at that speed and stay in control. BTW, the stability problem, stock, is due to enadequate rebound damping on the center shock (making the sled kick and buck off bigger bumps). This is also why we keep breaking limiter straps (and don't after the center shock is revalved).
One thing I did not do was create a second stage on rebound. On this shock I actually went back to the stock rebound stack. Note that compared to the REV-XP, it has a 2-slit piston and this does provide something of a softer 1st stage in rebound, but not as much as the REV-XP. If I ride my sled and a REV-XP X back to back, I can feel a little rebound harshness over very small bumps (just after going over something like a 1" ripple in the trail). I was tempted to try a 2nd rebound stage, except, there is a portion of shock/suspension travel, right when the sled bottoms out, where the shock velocity drops right down on these sleds. A soft first rebound stage will quite possibly create kickback. The REV-XP on the other hand has more linear shock velocity WRT suspension travel (BTW, the FX Nytro has VERY nice shock velocities - virtually the same as the REV-XP). Based on this, I recommend a single stage rebound stack for the main shock.
Still, compared to stock, the ride is absolutely incredible - everywhere from small bumps to huge bumps and jumps. It is also very comparable to a REV-XP MXZ X now also (the softer seat on the RTX is the final touch to bring it in-line).
For the center shock, you'll need to go to Mike Carver if you want the same setup as me (he can probably improve on it further too - now that he'll know where I went on the main). A second rebound stage could probably be added to the center, but it is the compression stack that is critical and it also might be more important to match the main shock for the best ride quality.
Finally, as you all know these custom valve stacks are typically fine tuned for the rider. If you are an extremely aggressive rider (I am fairly aggressive) or are heavier than me (I weigh 208 lbs), you might want to stiffen up the various stages. If you are a little less aggressive or lighter, you might want to soften everything up a little more, including the 3rd stage. The reason you might prefer a softer 3rd stage is once the bumps get into the 6-8" range and you are travelling at speed, the 3rd stage starts to kick in with my setup (and I can feel it - it really kicks in...). I don't think it is harsher than stock until the bumps get to at least 7-8" and when the moguls get really big, 1-1.5 feet, it starts to make use of all of the suspension travel on every bump (when riding at the worst speed for hitting the bumps; if you are brave enough to speed up to skipping speeds over 1-1.5 foot moguls it doesn't bottom out). The other place where my setup uses close to the full travel is through a big valley where the suspension is compressed for a long time and the softer 1st and 2nd stage let it compress a lot. I haven't bottomed it through a valley yet, but it feels like it can get close.
16x210 Spacer (to make sure the nut doesn't bottom on threads)
16x110 Spacer
26x150 End of first rebound stage
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 First rebound stage
2 slit piston bypass ports
30x200 First compression stage
30x200 End of first compression stage
18x150 Space before second compression stage kicks in .
30x200 Second compression stage
30x250 .
30x250 .
30x250 .
26x150 End of second compression stage
18x110 Space before third compression stage kicks in
16x110 Space before third compression stage kicks in
Hard stop (large thick washer)
As you can see my first stage is only 2x 0.200 mm thick valves, when stock the first stage was an incredible 12x 0.200 mm thick valves. Just imagine how much smoother my sled rides over small bumps. My second stage, with 0.150 mm open already, ends up being softer than the stock 1st stage also. My 3rd stage is fairly aggressive for this sled and it is very difficult to bottom out. If you want a little softer final stage, you could use a 16x150 3rd stage spacer instead of the 16x110. Of course my center shock is definitely contributing to the damping also, but the main shock does more of the work on big bumps.
FYI, Mike Carver's center shock setup has a soft 1st and 2nd stage compared to stock combined with a fairly aggressive 3rd stage too. It works well.
Yesterday I rode a stretch of trail with 1-2 foot moguls for about 2 miles. It bottomed out twice when I totally missed some of the bigger doubles (jumping from one mogul and hitting the up-slope on another) and when I put my hands on the shocks to see how hot they were, both were comfortably warm and free of snow (I had been riding hard on rough trails before that very rough stretch for about 2 hours). Stock, the non-functional center shock was always covered in snow and ice and the sled would have been bottoming and kicking and bucking everywhere on that trail. Stock I would not have been able to travel that trail at that speed and stay in control. BTW, the stability problem, stock, is due to enadequate rebound damping on the center shock (making the sled kick and buck off bigger bumps). This is also why we keep breaking limiter straps (and don't after the center shock is revalved).
One thing I did not do was create a second stage on rebound. On this shock I actually went back to the stock rebound stack. Note that compared to the REV-XP, it has a 2-slit piston and this does provide something of a softer 1st stage in rebound, but not as much as the REV-XP. If I ride my sled and a REV-XP X back to back, I can feel a little rebound harshness over very small bumps (just after going over something like a 1" ripple in the trail). I was tempted to try a 2nd rebound stage, except, there is a portion of shock/suspension travel, right when the sled bottoms out, where the shock velocity drops right down on these sleds. A soft first rebound stage will quite possibly create kickback. The REV-XP on the other hand has more linear shock velocity WRT suspension travel (BTW, the FX Nytro has VERY nice shock velocities - virtually the same as the REV-XP). Based on this, I recommend a single stage rebound stack for the main shock.
Still, compared to stock, the ride is absolutely incredible - everywhere from small bumps to huge bumps and jumps. It is also very comparable to a REV-XP MXZ X now also (the softer seat on the RTX is the final touch to bring it in-line).
For the center shock, you'll need to go to Mike Carver if you want the same setup as me (he can probably improve on it further too - now that he'll know where I went on the main). A second rebound stage could probably be added to the center, but it is the compression stack that is critical and it also might be more important to match the main shock for the best ride quality.
Finally, as you all know these custom valve stacks are typically fine tuned for the rider. If you are an extremely aggressive rider (I am fairly aggressive) or are heavier than me (I weigh 208 lbs), you might want to stiffen up the various stages. If you are a little less aggressive or lighter, you might want to soften everything up a little more, including the 3rd stage. The reason you might prefer a softer 3rd stage is once the bumps get into the 6-8" range and you are travelling at speed, the 3rd stage starts to kick in with my setup (and I can feel it - it really kicks in...). I don't think it is harsher than stock until the bumps get to at least 7-8" and when the moguls get really big, 1-1.5 feet, it starts to make use of all of the suspension travel on every bump (when riding at the worst speed for hitting the bumps; if you are brave enough to speed up to skipping speeds over 1-1.5 foot moguls it doesn't bottom out). The other place where my setup uses close to the full travel is through a big valley where the suspension is compressed for a long time and the softer 1st and 2nd stage let it compress a lot. I haven't bottomed it through a valley yet, but it feels like it can get close.
ReX
TY 4 Stroke God
One warning for all of you with 07/08 Apex RTXs...
If you go ahead and revalve your shocks right, it will ride incredibly well - so well, you can keep up with anyone riding on a REV-XP MXZ X.
Unfortunately, if you do ride it very hard, you'll probably end up eventually breaking both the front and rear pivot arms. I still can't be certain if mine were about to break prior to revalving the main shock, or if revalving the main shock was what pushed it over the edge. I did break both of them though.
I'll post some pictures on the cracks and what I did to fix and reinforce the pivot arms - hopefully permanently. If you want to ride very hard, it is probably worth reinforcing them along with the shock revalve.
At that point you'll end up with the ultimate, high performance, 4-stroke, rough trail sled available anywhere.
Actually I also reinforced my tunnel also after seeing the buckled tunnels on the GTs in the previous years. I purchased the reinforcements used on the GT and, after customizing them to fit the RTX, installed them. These parts make it so the weight of the muffler doesn't buckle the tunnel when the suspension bottoms out hard (of course now that it doesn't bottom out anymore this is probably not an issue anymore either). My honest opinion is these are not required unless your sled needs to be able to handle severe bottoming out. I very much doubt I need them at this point.
If you go ahead and revalve your shocks right, it will ride incredibly well - so well, you can keep up with anyone riding on a REV-XP MXZ X.
Unfortunately, if you do ride it very hard, you'll probably end up eventually breaking both the front and rear pivot arms. I still can't be certain if mine were about to break prior to revalving the main shock, or if revalving the main shock was what pushed it over the edge. I did break both of them though.
I'll post some pictures on the cracks and what I did to fix and reinforce the pivot arms - hopefully permanently. If you want to ride very hard, it is probably worth reinforcing them along with the shock revalve.
At that point you'll end up with the ultimate, high performance, 4-stroke, rough trail sled available anywhere.
Actually I also reinforced my tunnel also after seeing the buckled tunnels on the GTs in the previous years. I purchased the reinforcements used on the GT and, after customizing them to fit the RTX, installed them. These parts make it so the weight of the muffler doesn't buckle the tunnel when the suspension bottoms out hard (of course now that it doesn't bottom out anymore this is probably not an issue anymore either). My honest opinion is these are not required unless your sled needs to be able to handle severe bottoming out. I very much doubt I need them at this point.
SledFreak
TY 4 Stroke God
- Joined
- Feb 7, 2005
- Messages
- 5,511
- Location
- Ontario. Canada
- Country
- Canada
- Snowmobile
- Current 2020 ThunderCat. - SOLD!
Got a Phone and Contact Number for Carver Performance?
ReX
TY 4 Stroke God
SledFreak said:
http://www.carverperformance.com/home.htm
(218) 964-5670
BTW, I sent them my valve stack details and a link to this page so they should be in a good position to help you guys out.
Good post, ReX. Shock tuning can be quite an item to get your head around... you are giving folks some great info, thanks for sharing.
sawsalesman
Expert
So am I to assume that this type of revalve you did on your RTX can also be done with the KYB shock on my Mono ER Apex?
ReX
TY 4 Stroke God
sawsalesman said:
Any sled with rebuildable shocks can benefit from a multi-stage valve stack.
ReX
TY 4 Stroke God
Last night I had an opportunity to back to back compare my 2007 RTX to a 2008 REV-XP MXZ X on both smooth and rough trails.
I am extremely pleased to be able to say they are both truly excellent performers on both smooth and rough trails. Even my buddy, who always went on about how much better the MXZ X rode than his (now parked and up for sale) Apex ER and how much better his Apex ER rode than my 07 Apex RTX, had to agree that my 2007 RTX now rides just as well as the MXZ X.
On smoother trails the ride is Cadillac smooth, with every little bump simply disappearing without a hint of it. As the trails get rougher, the suspensions firm up perfectly, providing incredible bottoming control.
One stretch of trail was littered with 12"-20" moguls and both of us zipped down the trail with the sleds maintaining perfect control and stability while using the full suspension travel (it was "just" lightly touching the bumps stops once in a while when landing on the next rise - just enough to clean the snow off them now and then).
On the final section of trail on the way home, the railway bed was full of 6" to 12" whoops and we rode it everywhere from low speeds to very high speeds and the suspensions soaked up the bumps incredibly well, again with perfect stability and without bottoming out at all.
If you own a 2007 RTX, I highly recommend upgrading to multi-stage shock valving for the skid and getting rid of the anti-bottomers. If you are not all that aggressive in the bumps, you might want to slightly soften off the 3rd and final stage in compression a little compared to my setup (as mentioned in my posts above). You will be blown away by the level of comfort, control, stability and anti-bottoming resistance. The difference is like night and day and you'll find it difficult to believe it is the same sled.
I also lined up with the REV-XP a couple of times (he wanted to beat me again since he couldn't quite keep up with me on the tight twisty trails) and with the new Predator 1" track, 144 1.075" Roetin Hornets and still stock clutching I beat him every time.
Even though the trails were very rough in places, it was a treat to be riding such an incredibly well performing sled. I always have a great time sledding, but it was even better because of the awesome performance everywhere.
I am extremely pleased to be able to say they are both truly excellent performers on both smooth and rough trails. Even my buddy, who always went on about how much better the MXZ X rode than his (now parked and up for sale) Apex ER and how much better his Apex ER rode than my 07 Apex RTX, had to agree that my 2007 RTX now rides just as well as the MXZ X.
On smoother trails the ride is Cadillac smooth, with every little bump simply disappearing without a hint of it. As the trails get rougher, the suspensions firm up perfectly, providing incredible bottoming control.
One stretch of trail was littered with 12"-20" moguls and both of us zipped down the trail with the sleds maintaining perfect control and stability while using the full suspension travel (it was "just" lightly touching the bumps stops once in a while when landing on the next rise - just enough to clean the snow off them now and then).
On the final section of trail on the way home, the railway bed was full of 6" to 12" whoops and we rode it everywhere from low speeds to very high speeds and the suspensions soaked up the bumps incredibly well, again with perfect stability and without bottoming out at all.
If you own a 2007 RTX, I highly recommend upgrading to multi-stage shock valving for the skid and getting rid of the anti-bottomers. If you are not all that aggressive in the bumps, you might want to slightly soften off the 3rd and final stage in compression a little compared to my setup (as mentioned in my posts above). You will be blown away by the level of comfort, control, stability and anti-bottoming resistance. The difference is like night and day and you'll find it difficult to believe it is the same sled.
I also lined up with the REV-XP a couple of times (he wanted to beat me again since he couldn't quite keep up with me on the tight twisty trails) and with the new Predator 1" track, 144 1.075" Roetin Hornets and still stock clutching I beat him every time.
Even though the trails were very rough in places, it was a treat to be riding such an incredibly well performing sled. I always have a great time sledding, but it was even better because of the awesome performance everywhere.
ReX
TY 4 Stroke God
I thought I should also post an update on the shock valving.
I found there were a couple of longer "whoops" or valleys, where the suspension was being compressed for a relatively long period that it would "just" bottom out. This was only once a lot of ice had built up in my tunnel as is due to the extremely soft 1st and 2nd stage valving. If there was a bump at the end of a long "whoop", it might bottom out a little harder than I'd like also.
So, considering this and considering I tend to do a lot of saddle bag trips (with 50+ lbs on the back), I slightly tweaked the low and mid-speed damping - back to a previous stack I had tried. This is very close, but "just" stiff enough to control suspension compression through those long dips/whoops (or whatever we want to call them...). I'll also turn my torsion spring preload up to medium or high with loaded saddle bags (note that my torsion springs are rearched so my low is similar to stock on high).
Here is what I'm running now, and for me it is absolutely perfect:
16x210 Spacer (to make sure the nut doesn't bottom on threads)
26x150 End of first rebound stage
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 First rebound stage
2 slit piston bypass ports
30x250 First compression stage
30x200 End of first compression stage
18x150 Space before second compression stage kicks in .
30x250 Second compression stage
30x250 .
30x250 .
30x250 .
26x150 End of second compression stage
18x110 Space before third compression stage kicks in
16x110 Space before third compression stage kicks in
Hard stop (large thick washer)
I expect that for a lighter or less aggressive rider that the following would probably be ideal (slightly softer than my current in 1st, 2nd and 3rd):
16x210 Spacer (to make sure the nut doesn't bottom on threads)
16x110 Spacer
26x150 End of first rebound stage
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 First rebound stage
2 slit piston bypass ports
30x200 First compression stage
30x200 End of first compression stage
18x150 Space before second compression stage kicks in .
30x200 Second compression stage
30x200 .
30x250 .
30x250 .
26x150 End of second compression stage
18x110 Space before third compression stage kicks in
16x150 Space before third compression stage kicks in
Hard stop (large thick washer)
I found there were a couple of longer "whoops" or valleys, where the suspension was being compressed for a relatively long period that it would "just" bottom out. This was only once a lot of ice had built up in my tunnel as is due to the extremely soft 1st and 2nd stage valving. If there was a bump at the end of a long "whoop", it might bottom out a little harder than I'd like also.
So, considering this and considering I tend to do a lot of saddle bag trips (with 50+ lbs on the back), I slightly tweaked the low and mid-speed damping - back to a previous stack I had tried. This is very close, but "just" stiff enough to control suspension compression through those long dips/whoops (or whatever we want to call them...). I'll also turn my torsion spring preload up to medium or high with loaded saddle bags (note that my torsion springs are rearched so my low is similar to stock on high).
Here is what I'm running now, and for me it is absolutely perfect:
16x210 Spacer (to make sure the nut doesn't bottom on threads)
26x150 End of first rebound stage
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 First rebound stage
2 slit piston bypass ports
30x250 First compression stage
30x200 End of first compression stage
18x150 Space before second compression stage kicks in .
30x250 Second compression stage
30x250 .
30x250 .
30x250 .
26x150 End of second compression stage
18x110 Space before third compression stage kicks in
16x110 Space before third compression stage kicks in
Hard stop (large thick washer)
I expect that for a lighter or less aggressive rider that the following would probably be ideal (slightly softer than my current in 1st, 2nd and 3rd):
16x210 Spacer (to make sure the nut doesn't bottom on threads)
16x110 Spacer
26x150 End of first rebound stage
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 .
26x150 First rebound stage
2 slit piston bypass ports
30x200 First compression stage
30x200 End of first compression stage
18x150 Space before second compression stage kicks in .
30x200 Second compression stage
30x200 .
30x250 .
30x250 .
26x150 End of second compression stage
18x110 Space before third compression stage kicks in
16x150 Space before third compression stage kicks in
Hard stop (large thick washer)
Man my brain is on overload. I don't understand it all, but this is what makes this site the best Yamaha site on the web. You do walker evans shocks. LOL Maxdlx
Soldier'spapa
Lifetime Member
- Joined
- Mar 21, 2006
- Messages
- 729
- Location
- Naperville, IL
- Country
- USA
- Snowmobile
- 2018 Sidewinder Ltx LE 50th Anniversary
Wow! What an incredible job Rex... Thank you for going through all of this R&D!
I have been trying to get my wife's 07 Phazer FX to ride like the Rev we sold. I have had the shocks re-valved by one of the site sponsors and while the sled is significantly better it still is a far cry from the Rev. Can you tell me if this multi stage valving can be added to my Phazer shocks?
I have been trying to get my wife's 07 Phazer FX to ride like the Rev we sold. I have had the shocks re-valved by one of the site sponsors and while the sled is significantly better it still is a far cry from the Rev. Can you tell me if this multi stage valving can be added to my Phazer shocks?
ReX
TY 4 Stroke God
Soldier'spapa said:
I don't know anything about the shocks in the Phazer, but since they are rebuildable, I would assume they are using washer based valve stacks. If so, then yes they can use multi-stage valving.
If the shocks are the same and with the weight being similar, maybe the REV valving can even be used directly in the Phazer??
chadman
Expert
Rex, were the specs you gave us for the front skid shock? What did you do for the rear skid shock or dampener shock?
smacho
Extreme
smacho said:I just got off the phone with Bruce from Pioneer -- He spoke in generallities - said better at low speed, better rebound, seemed to be able to predict my complaints. So, I asked him to fix it.
With luck & timing (& snow) I will have it back on the trail this weekend. I will post my opinion of the results. Without luck and /or snow I will post later --
Got it back this morning -- rode about 80 miles today
It was a mechanical miricle!
I just kept wondering: Why Yamaha didn't build it like this? Or as an option?
Rex thanks for the Thread ---
horny red devil
Pro
I don't know what they are doing? It sounds to me like the same problem they had with a 2002 viper. I had the shock update done on my viper and said ok! perfect than I bought an rx1 for the skid(expert x) and said perfect if I don't like it swap skids with the viper and sell (6300 miles) on both. My problem is that I rode a 2002 zr 900 and that thing rode & handled great stock whats up? We are in to the $10,000 range now we should expect alot more than a 2002 arctic cat skid stock!!!!Motors are great last forever let us just put a skid in their with the same motors. Alot of people switched from other brands for reliability but I think those other brands are catching up and ride quality is coming into play. Just a thought!!!!!
