twowheels
New member
You could ask, and I could sell it to you. Suspension work helps pay for my GasGas habit
Diving into the Sachs 48mm forks - wish me luck?
- Thread starter n_green
- Start date
You could ask, and I could sell it to you. Suspension work helps pay for my GasGas habit
You could ask, and I could sell it to you. Suspension work helps pay for my GasGas habit
PM sent
Ok I got the base valve back in. All I did was re-assemble the fork without oil and then turn the fork upside down and compress it, this held the cartridge in place and allowed me to tighten the base valve using a ratchet. Only downside of this method is you can't torque the valve up as all that is stopping the whole thing spinning is your hand. Minimum setting on my bigger torque wrench is 28nm and they aren't there, so they are at the specification of 'tight'.
I've filled them back up with oil and they are the right way up again and on the bike and no leaks yet so I'm going to call that a success. Now to see the difference between the stock compression stack and the one I got from Simmo.
I've filled them back up with oil and they are the right way up again and on the bike and no leaks yet so I'm going to call that a success. Now to see the difference between the stock compression stack and the one I got from Simmo.
Tried a shim stack
Tried the base valve shim stack Simmo originally tried today:
23.1 (2)
14.1
23.1
22.1 (3)
20.1 (2)
18.1
16.1
12.3
washer
left the rebound and mid-valve alone.
Then I went to my local rock garden riding area and rode 35k's of it. Big rocks, little rocks, rock ledges to bash into, rock ledges to drop off, logs, roots, ruts you name it it's in this place.
It definitely made a difference to the feeling of the fork. They are better in that the harshness has all but gone from them when hitting square edged objects, however I believe it comes at the cost of the fork diving through its' stroke.
I played with the comp and rebound clickers throughout the day and the best I could get it was plush over typical trail trash and then some bigger stuff, it was also very good over larger (big rocks, ledges, logs etc) stuff.
The problem was the fork seemed to dive under hard braking or big hits, this in turn caused savage rebound and pogo'd the bike front to back. It also upset the rear shock, which up to this point I've been happy with.
I upped the compression and settled on 7 clicks out, also had to wind rebound in the around 7 clicks. This firmed up the forks so they didn't dive as often and the rebound was slightly more controlled, though still savage during big hits or sandy whoops/multiple downhill ledges.
Firming it up again to 5 clicks of compression brought the harshness back into the stroke and also started deflecting a lot more.
The fork has also lost its' ability to perform better the harder and faster you push it, it felt amazing initially when I was riding through the slower technical stuff but as soon as you start hitting the same and slightly bigger stuff in 2nd or 3rd it gets scary as the whole bike pogo's front to back.
In short, this stack isn't a magic fix for me and I think I need to play a bit more with it along with making a mid-valve stack/using two wheels mid-valve kit.
Tried the base valve shim stack Simmo originally tried today:
23.1 (2)
14.1
23.1
22.1 (3)
20.1 (2)
18.1
16.1
12.3
washer
left the rebound and mid-valve alone.
Then I went to my local rock garden riding area and rode 35k's of it. Big rocks, little rocks, rock ledges to bash into, rock ledges to drop off, logs, roots, ruts you name it it's in this place.
It definitely made a difference to the feeling of the fork. They are better in that the harshness has all but gone from them when hitting square edged objects, however I believe it comes at the cost of the fork diving through its' stroke.
I played with the comp and rebound clickers throughout the day and the best I could get it was plush over typical trail trash and then some bigger stuff, it was also very good over larger (big rocks, ledges, logs etc) stuff.
The problem was the fork seemed to dive under hard braking or big hits, this in turn caused savage rebound and pogo'd the bike front to back. It also upset the rear shock, which up to this point I've been happy with.
I upped the compression and settled on 7 clicks out, also had to wind rebound in the around 7 clicks. This firmed up the forks so they didn't dive as often and the rebound was slightly more controlled, though still savage during big hits or sandy whoops/multiple downhill ledges.
Firming it up again to 5 clicks of compression brought the harshness back into the stroke and also started deflecting a lot more.
The fork has also lost its' ability to perform better the harder and faster you push it, it felt amazing initially when I was riding through the slower technical stuff but as soon as you start hitting the same and slightly bigger stuff in 2nd or 3rd it gets scary as the whole bike pogo's front to back.
In short, this stack isn't a magic fix for me and I think I need to play a bit more with it along with making a mid-valve stack/using two wheels mid-valve kit.
Off topic but also on topic, just saw a photo of a Sachs base valve piston from new '13 Beta 300, looks identical to mine (6 ports) except where my piston has 2 ports going to valve stack and 4 ports going to the rebound check plate the newer Beta piston has 3 and 3 ports. So (without measuring them to confirm they are in fact same sized piston with same size ports) the new Beta seems to have improved flow through the compression stroke but less flow through the rebound stroke. (Not taking into account what is occurring at the Rebound piston and mid valve)
Random info huh.
Random info huh.
swazi_matt
Active member
And to add to the randomness i believe that the new Sachs forks now use a more common shim size IDOff topic but also on topic, just saw a photo of a Sachs base valve piston from new '13 Beta 300, looks identical to mine (6 ports) except where my piston has 2 ports going to valve stack and 4 ports going to the rebound check plate the newer Beta piston has 3 and 3 ports. So (without measuring them to confirm they are in fact same sized piston with same size ports) the new Beta seems to have improved flow through the compression stroke but less flow through the rebound stroke. (Not taking into account what is occurring at the Rebound piston and mid valve)
Random info huh.
Nope, the '13 Beta Sachs forks are still running 7mm ID shims. Not sure if the mid valve shims are still 9mm though.
I was told there is a company in US making new base valve and rebound taps that accepted 6 & 8mm shims, should be able to buy them, swap them over and hey presto normal shims to play with. Hopefully be getting more info on that today but I imagine it would be costly, not to mention you would have to get a new piston for each tap.
Haven't updated this in a while, I've done a few more tests using a few difference stacks, the first was using stock rebound stack, twowheels mid-valve kit and this base valve:
23.1 (1)
14.1
23.1 (5)
22.1
20.1
18.1
16.1
14.1
12.3
I rode about 80k's of rocky, root infested, off-camber steep up and downhill single trail. I wasn't happy with the fork at all, the initial compression on square edges was good but the fork couldn't hold itself up in the stroke during repeated impacts and I'm pretty sure on moderately paced downhills it started cavitating as it would pogo like a mutha and seemed to have no rebound damping at all. I also had little confidence in the front end on off-camber trails. It just wanted to push and not turn in.
Following this I went back to using the stock base valve, stock rebound and two wheels mid valve kit. I rode at the same place almost the same tracks.
Big difference, the fork could hold itself up in the stroke, I had a lot more confidence in its ability to stick going into corners, both flat and off-camber, it's nowhere near as harsh on square edges any more.
Negatives are it is still harsh to a degree on square edges, and the harder/faster they are hit the harsher it is. It is still no-where near as harsh as what it used to be. Also when the speed picks up it returns to its natural preference of deflecting off the object rather then soaking it up, again it doesn't deflect as badly as stock valving but it does still deflect.
My rebound stack is also too soft, to gain the confidence in the fork going into turns I had to tighten the rebound past where it started affecting the compression damping, this obviously led to the fork getting some of its harshness back and if I were to simply beef up the rebound stack I reckon these forks would be fine.
Twowheels midvalve kit is a good simple solution to fix the forks quickly and for the majority of punters, myself included, with a tweak to the rebound stack these forks would satisfy most people.
However, I have started playing with this suspension stuff now and I kind of like it, so I'm going to continue playing. As I mentioned the kit fixed the harshness on low speed square edges, it ate up the slow speed rock gardens and root infested climbs/descents. But because they eat it up it inspires confidence which builds speed and they just can't handle the same square edges at a decent speed.
The weak rebound stack definitely isn't helping things. I'm going to continue playing and try and sort these forks out, I have no idea what I'm doing but I have a bucket load of shims so I may as well have a go.
23.1 (1)
14.1
23.1 (5)
22.1
20.1
18.1
16.1
14.1
12.3
I rode about 80k's of rocky, root infested, off-camber steep up and downhill single trail. I wasn't happy with the fork at all, the initial compression on square edges was good but the fork couldn't hold itself up in the stroke during repeated impacts and I'm pretty sure on moderately paced downhills it started cavitating as it would pogo like a mutha and seemed to have no rebound damping at all. I also had little confidence in the front end on off-camber trails. It just wanted to push and not turn in.
Following this I went back to using the stock base valve, stock rebound and two wheels mid valve kit. I rode at the same place almost the same tracks.
Big difference, the fork could hold itself up in the stroke, I had a lot more confidence in its ability to stick going into corners, both flat and off-camber, it's nowhere near as harsh on square edges any more.
Negatives are it is still harsh to a degree on square edges, and the harder/faster they are hit the harsher it is. It is still no-where near as harsh as what it used to be. Also when the speed picks up it returns to its natural preference of deflecting off the object rather then soaking it up, again it doesn't deflect as badly as stock valving but it does still deflect.
My rebound stack is also too soft, to gain the confidence in the fork going into turns I had to tighten the rebound past where it started affecting the compression damping, this obviously led to the fork getting some of its harshness back and if I were to simply beef up the rebound stack I reckon these forks would be fine.
Twowheels midvalve kit is a good simple solution to fix the forks quickly and for the majority of punters, myself included, with a tweak to the rebound stack these forks would satisfy most people.
However, I have started playing with this suspension stuff now and I kind of like it, so I'm going to continue playing. As I mentioned the kit fixed the harshness on low speed square edges, it ate up the slow speed rock gardens and root infested climbs/descents. But because they eat it up it inspires confidence which builds speed and they just can't handle the same square edges at a decent speed.
The weak rebound stack definitely isn't helping things. I'm going to continue playing and try and sort these forks out, I have no idea what I'm doing but I have a bucket load of shims so I may as well have a go.
GMP
Active member
A few thoughts:
Rebound clicker should not affect compression to the point of feeling a difference, if its a normal mid/rebound piston setup as I suspect it is.
Light HS rebound sometimes feels like a comp spike as the fork starts to reset from a deep compression with a lot of spring force behind it. Zoke 45s and 48s need help here too.
Maybe you should consider upping the spring rate, lowering the oil level, and dropping the preload. I've found this works pretty well in increasing the scope of a fork as far as terrain, as I have to race in everything from rocks to sand.
What is stock comp stack?
Rebound clicker should not affect compression to the point of feeling a difference, if its a normal mid/rebound piston setup as I suspect it is.
Light HS rebound sometimes feels like a comp spike as the fork starts to reset from a deep compression with a lot of spring force behind it. Zoke 45s and 48s need help here too.
Maybe you should consider upping the spring rate, lowering the oil level, and dropping the preload. I've found this works pretty well in increasing the scope of a fork as far as terrain, as I have to race in everything from rocks to sand.
What is stock comp stack?
Stock comp stack is:
23.1 (5)
22.1 (3)
20.1 (2)
18.1
16.1
14.1
12.3
washer
Rebound Shim stack is:
Piston
23 x .1 (2)
20 x .1
18 x .1
16 x .1
12 x .15
10 x .3
13 x 2.15 washer (2)
There are also 2 x 1.1mm bleed holes in the rebound side of the piston
Mid-valve shim stack is:
Piston,
25 x .2 check plates (2)
and has a 1.1mm float.
The rebound clickers definitely affect compression and have done so with every stack I have tried. By closing off the bypass enough to actually get the weak rebound stack to work it is in turn also closing up the MV bypass exposing its stiffness ala harshness. Well thats my take on it anyway, as mentioned I'm a beginner hack and still learning. I could be way off the mark, but thats the joy of learning
Interesting point about the rebound feeling like compression spike, it's definitely something I may have confused, I'm just a hack and I'm also learning how to actually 'feel' what the suspension is doing. I need to set up a video camera on a rut/rocky step and hit it repeatedly to see what the suspension is doing I guess, that may offer me more of an idea of what is going on.
I have re-sprung the front to suit my weight, I have .46 springs up front with 3mm preload and a 110mm air gap. I haven't tested the sag figures though so maybe I need to look at that. I agree I could probably take some oil out as I rarely (read never) bottom, that I can feel and after an average trail ride will still have an inch or two of travel that wasn't used.
Thanks for the info though I'll take it on board and look at it next time I have them apart.
GMP
Active member
That last comp stack you tried (not the stock one) seems a little soft on the initial stage and stiff on the second stage. Crossover is thin as well. Try something like this:
23x.1 (4)
14x.2 (x over)
23x.1 (2)
22x.1
20x.1
18x.1
16x.1
14x.1
12x.3
washer
This is more like a traditional 2 stage. Stiffer face may hold it up better, thickover crossover allow it to flow more before 2nd stage.
Rebound looks reasonable, but I have never been in a Sachs fork so all I woud say is try to determine if your problem is HS or LS rebound and add accordingly.
Like I said never had rebound clicker affest compression in Zokes or WPs. I think that would mean oil pressure is very high on the rebound side of the piston during compression. Odd. In any case, it should only be a low speed effect, as a fixed orafice(clicker adjustment needle) is essentially closed at high flow rates.
I am not a tuner and this is just general info based on what seems to work in most other forks.
23x.1 (4)
14x.2 (x over)
23x.1 (2)
22x.1
20x.1
18x.1
16x.1
14x.1
12x.3
washer
This is more like a traditional 2 stage. Stiffer face may hold it up better, thickover crossover allow it to flow more before 2nd stage.
Rebound looks reasonable, but I have never been in a Sachs fork so all I woud say is try to determine if your problem is HS or LS rebound and add accordingly.
Like I said never had rebound clicker affest compression in Zokes or WPs. I think that would mean oil pressure is very high on the rebound side of the piston during compression. Odd. In any case, it should only be a low speed effect, as a fixed orafice(clicker adjustment needle) is essentially closed at high flow rates.
I am not a tuner and this is just general info based on what seems to work in most other forks.
Was thinking today and a mate agrees the fork springs most likely are the incorrect weight for me. I'm only running .46 springs up front. These were sold to me based on info given to a tuner along with a 5.6 spring. I recently upped the spring to a 6.0 as the 5.6 was too soft. I'm thinking the fork springs may also be one or two rates too soft.
When I ride it it never feels plush, and the bigger faster hits feel harsh. A mate who is 20kg lighter then me loves my forks thinks they're great. I'd say what's happening is the springs are correct for him and when he rides it the fork sits up in its stroke as its supposed to. With me obviously they sit that bit lower in the stroke and the harshness I'm feeling is compression related not rebound related.
I'd never considered this as an option as I had blind faith the tuner would have sold me the correct springs. Wasnt til my mate put it to me as a theory I thought about it. Ill have to confirm with sag measurements but I reckon this is my main problem. As they say you can't re-valve for the wrong springs so looks like ill be up for new fork springs now too.
Anyone want a 5.6 spring and .46 springs to suit Sachs suspension?
When I ride it it never feels plush, and the bigger faster hits feel harsh. A mate who is 20kg lighter then me loves my forks thinks they're great. I'd say what's happening is the springs are correct for him and when he rides it the fork sits up in its stroke as its supposed to. With me obviously they sit that bit lower in the stroke and the harshness I'm feeling is compression related not rebound related.
I'd never considered this as an option as I had blind faith the tuner would have sold me the correct springs. Wasnt til my mate put it to me as a theory I thought about it. Ill have to confirm with sag measurements but I reckon this is my main problem. As they say you can't re-valve for the wrong springs so looks like ill be up for new fork springs now too.
Anyone want a 5.6 spring and .46 springs to suit Sachs suspension?
Jakobi
Super Moderator
I'm running .46 springs up front and I'm only 75kgs nudey. Around 95-100kgs fully kitted with tools and fluids. Using a 5.4 rear. I think you're probably right. Have you had a go at measuring up your sag on the front? It can be hard due to stiction, but with a few goes and some averages you can get a ballpark figure.
Sag #'s
Measured my sag today as follows:
Front:
0.46 springs, 4mm preload;
43mm static sag
76mm rider sag
Rear:
6.0 spring, 10mm preload;
30mm static sag
107mm rider sag
I had all of my gear on (turns out I wear exactly 20kgs of crap - total rider weight = 112kg) however the fuel tank only had about 3l in it, doubt that would affect the figures too much.
Based on the advice here I'm pretty close, about spot on with the rear and maybe slightly too soft on the fronts. The front feels noticeably softer then the rear now I've upgraded the rear spring so I'll go up on the forks anyway, just unsure if I should go up to 0.48's or 0.50s??
Any advice? I've been a consistent 92kg naked for the past 10 years so I can't see that changing and I only carry basic tools etc in the camelback so I can't see any way of shaving weight.
Measured my sag today as follows:
Front:
0.46 springs, 4mm preload;
43mm static sag
76mm rider sag
Rear:
6.0 spring, 10mm preload;
30mm static sag
107mm rider sag
I had all of my gear on (turns out I wear exactly 20kgs of crap - total rider weight = 112kg) however the fuel tank only had about 3l in it, doubt that would affect the figures too much.
Based on the advice here I'm pretty close, about spot on with the rear and maybe slightly too soft on the fronts. The front feels noticeably softer then the rear now I've upgraded the rear spring so I'll go up on the forks anyway, just unsure if I should go up to 0.48's or 0.50s??
Any advice? I've been a consistent 92kg naked for the past 10 years so I can't see that changing and I only carry basic tools etc in the camelback so I can't see any way of shaving weight.
Ended up buying the 0.50 springs. They may be slightly too firm but I'm constantly re-valving the front end anyway these days so no matter 
They should also balance the bike nicely with the 6.0 spring.
Doing a test ride tomorrow, looking forward to seeing if I notice any changes.
They should also balance the bike nicely with the 6.0 spring.
Doing a test ride tomorrow, looking forward to seeing if I notice any changes.
Pre-load Measurement on Forks
Learnt something today. The 0.46 springs and the stock springs from the forks are 460mm long. Actual measurement is closer to 455mm. Measuring from the spring seat on the cartridge to the spring seat under the fork cap I got a measurement of 457mm. So stock springs have -2mm pre-load right?
Wrong I didn't realise when taking this measurement you have to take into account the length of the top out spring travel. The cartridge rod is fitted with a top-out spring with approx 10mm of travel. With the fork cap attached to the cartridge rod and the top tube undone and slid all the way down you can feel this extra travel by pulling up on the cap. So really potentially the free space measurement is 467mm (457mm + 10mm). So the stock springs actually have -12mm of pre-load
The 0.50 springs I bought are 472mm long so without spacers will be +5mm preloaded.
Obviously I found all this out by ringing the tuner and complaining the springs he just sold me will have +15mm pre-load. He chuckled then explained the above.
Anyway, I didn't know this and don't know if it's common knowledge. So there it is for future reference.
Learnt something today. The 0.46 springs and the stock springs from the forks are 460mm long. Actual measurement is closer to 455mm. Measuring from the spring seat on the cartridge to the spring seat under the fork cap I got a measurement of 457mm. So stock springs have -2mm pre-load right?
Wrong I didn't realise when taking this measurement you have to take into account the length of the top out spring travel. The cartridge rod is fitted with a top-out spring with approx 10mm of travel. With the fork cap attached to the cartridge rod and the top tube undone and slid all the way down you can feel this extra travel by pulling up on the cap. So really potentially the free space measurement is 467mm (457mm + 10mm). So the stock springs actually have -12mm of pre-load
The 0.50 springs I bought are 472mm long so without spacers will be +5mm preloaded.
Obviously I found all this out by ringing the tuner and complaining the springs he just sold me will have +15mm pre-load. He chuckled then explained the above.
Anyway, I didn't know this and don't know if it's common knowledge. So there it is for future reference.
A mate has been helping me out with the suspension and after some advice received over on Thumpertalk forum I re-valved the front end again. Thanks to the people over on the TT forum for their advice to Stu.
The stack we used is slightly different from the ones suggested as we didn't have some of the shims suggested. Despite finding a mob in the US who can supply 9mm ID shims there is still limited sizes available.
This is the place I found my shims
This is the stack I used:
BV:
23.1
14.1
23.1 (3)
20.1
18.1
16.1
14.1
12.3
MV:
24.1
12.1
24.1 (2)
20.1
18.1
16.1
11.2
Float has been reduced from 1.1mm to 0.6mm
Rebound:
Stack remained the same as per stock. I was advised to JB weld the 2 x 1.2mm bleed holes closed to firm it up however I didn't do this prior to the ride.
Fork springs were upped from 0.46 to 0.50 with 6mm preload as the bike was noticeably unbalanced after putting the 6.0 shock spring on.
Results:
HEAPS BETTER.
The forks are now plush, super plush. Perhaps too plush.
The fork rides a lot higher in its stroke now. The forks feel perhaps too high, and it is noticeable, though barely that the front seems to ride higher then the rear. They have been dropped through the triples by .5mm and I may look at either dropping them more or adding some preload to the rear spring as race sag on the rear is approx 107mm now.
The forks soak up trail trash with ease and are nice and plush (read perhaps slightly too soft) on high speed impacts. Throughout the day - 70k's at Letter A, single trail, twin trail, slow technical areas and open fast sections, including the whoops at the top of the concrete path track they didn't do anything nasty or surprising at all. They are really really good, but not yet great.
Flaws I picked up on are:
The fork dives slightly under brakes and on initial low speed compression. I put this down to the soft low speed stack on the MV.
Once it dives through this and begins using the high speed MV stack it is nice and progressive. It didn't blow through the stroke at any time throughout the day. Having said that I feel I could increase the stiffness of the high speed stack as it may be slightly too soft. On uphill inclines with lots of head sized rocks/roots etc when hitting them in 2nd gear I had to speed the rebound up to get it to return in time for the next hit, else it packed and became harsh. The problem with doing this is the rebound stack is too soft and speeding the rebound up to address this problem made them pogo on downhills and push on off-cambered trails.
So if I stiffen the MV stack up slightly the fork won't compress as much and won't have to rebound as far, which should fix address this problem?
Plan for the MV is to stiffen the LS and maybe HS stacks. I am thinking I'll either add a face shim to the LS stack and maybe increase the crossover to a 14.1 to start with. This will bring the float down to 0.5mm as well. I'm also toying with the idea of getting rid of the crossover altogether and running a straight stack.
I should mention that stock face shims for the MV are 25's. I am using 24's as thats all I could get. They seem to completely cover the ports and when closed I can't blow through them so they aren't acting as bleed shims, but I'm guessing it would be easier for these to open then for the 25's?
The base valve I'm happy with for now, I may stiffen it up slightly later but for now my nitpicking is with the MV.
Plan for rebound is to JB weld the two bleed holes up and see what happens from there. Doing this should also stiffen up the low speed MV compression as well.
I'll continue playing and updating as I go. But I am already pretty happy with these forks, they are 1 million times better then when I got them and the harshness is all but gone from them.
Anyone smarter then me care to advise if my thoughts above sound about right?
The stack we used is slightly different from the ones suggested as we didn't have some of the shims suggested. Despite finding a mob in the US who can supply 9mm ID shims there is still limited sizes available.
This is the place I found my shims
This is the stack I used:
BV:
23.1
14.1
23.1 (3)
20.1
18.1
16.1
14.1
12.3
MV:
24.1
12.1
24.1 (2)
20.1
18.1
16.1
11.2
Float has been reduced from 1.1mm to 0.6mm
Rebound:
Stack remained the same as per stock. I was advised to JB weld the 2 x 1.2mm bleed holes closed to firm it up however I didn't do this prior to the ride.
Fork springs were upped from 0.46 to 0.50 with 6mm preload as the bike was noticeably unbalanced after putting the 6.0 shock spring on.
Results:
HEAPS BETTER.
The forks are now plush, super plush. Perhaps too plush.
The fork rides a lot higher in its stroke now. The forks feel perhaps too high, and it is noticeable, though barely that the front seems to ride higher then the rear. They have been dropped through the triples by .5mm and I may look at either dropping them more or adding some preload to the rear spring as race sag on the rear is approx 107mm now.
The forks soak up trail trash with ease and are nice and plush (read perhaps slightly too soft) on high speed impacts. Throughout the day - 70k's at Letter A, single trail, twin trail, slow technical areas and open fast sections, including the whoops at the top of the concrete path track they didn't do anything nasty or surprising at all. They are really really good, but not yet great.
Flaws I picked up on are:
The fork dives slightly under brakes and on initial low speed compression. I put this down to the soft low speed stack on the MV.
Once it dives through this and begins using the high speed MV stack it is nice and progressive. It didn't blow through the stroke at any time throughout the day. Having said that I feel I could increase the stiffness of the high speed stack as it may be slightly too soft. On uphill inclines with lots of head sized rocks/roots etc when hitting them in 2nd gear I had to speed the rebound up to get it to return in time for the next hit, else it packed and became harsh. The problem with doing this is the rebound stack is too soft and speeding the rebound up to address this problem made them pogo on downhills and push on off-cambered trails.
So if I stiffen the MV stack up slightly the fork won't compress as much and won't have to rebound as far, which should fix address this problem?
Plan for the MV is to stiffen the LS and maybe HS stacks. I am thinking I'll either add a face shim to the LS stack and maybe increase the crossover to a 14.1 to start with. This will bring the float down to 0.5mm as well. I'm also toying with the idea of getting rid of the crossover altogether and running a straight stack.
I should mention that stock face shims for the MV are 25's. I am using 24's as thats all I could get. They seem to completely cover the ports and when closed I can't blow through them so they aren't acting as bleed shims, but I'm guessing it would be easier for these to open then for the 25's?
The base valve I'm happy with for now, I may stiffen it up slightly later but for now my nitpicking is with the MV.
Plan for rebound is to JB weld the two bleed holes up and see what happens from there. Doing this should also stiffen up the low speed MV compression as well.
I'll continue playing and updating as I go. But I am already pretty happy with these forks, they are 1 million times better then when I got them and the harshness is all but gone from them.
Anyone smarter then me care to advise if my thoughts above sound about right?
Re-valved the front again:
This is the stack I used:
BV (unchanged from the last ride):
23.1
14.1
23.1 (3)
20.1
18.1
16.1
14.1
12.3
MV:
24.1 (2)
12.1
24.1 (2)
20.1
18.1
16.1
11.2
Rebound:
23 x .1 (3)
20 x .1
18 x .1
16 x .1
12 x .15
10 x .3
13 x 2.15 washer (2)
2 x 1.2mm bleed holes in piston - closed using JB weld.
I also added 1mm of pre-load to the rear as on the last ride it felt like the front was slightly stronger then the rear. I played with too much at once, within the first hour of the ride I had to take the pre-load back off the rear, it turned everything to poo. With pre-load back to approximately 10mm the rear felt good again.
Now last valving stacks I was pretty happy with the front, it was super plush and apart from diving under brakes and falling slightly through the stroke on braking bumps they were good, slightly mushy but the best I've had them so far. Rebound was also far too quick, both high and low speed.
First up the rebound has improved somewhat by adding the face shim and filling in the bleed holes however it could still be a little stiffer. It was wet and slippery on the weekend on the front had a tendency to push down off-camber sections and push wide through corners. High speed was similar and it would start to pogo on downhill sections with lots of drop-offs and rocks.
Adding 1 face shim to the MV and reducing the float by .1mm has made a huge difference, and not for the better. It has stopped the forks from diving under brakes and they sit nice and high in their travel, so that bits' great. But I think the stack is now too stiff as they aren't as plush anymore and square edges once again jar (not nearly as much as the stock stack). I was also getting some deflection, most noticeably on angled tree roots and wet rocks, then again it was wet as mentioned so this could have contributed to the problem.
I'm also wondering if the MV is now too firm and pushed oil through the BV leading to cavitation on fast deep compressions such as steep downhills with ledges and rocks etc. As mentioned the forks began pogo-ing and they didn't do that with the previous MV stack.
I plan on firming up the rebound stack a bit more, not sure yet as to add another face shim to slow down the low speed and initial opening or add a larger clamp shim to firm up everything. Any thoughts?
The MV has me stumped, I really want something between the two stacks I have just used, one that prevents diving and falling through the stroke like the current stack but retains the plushness of the previous stack. Would removing one of the 24.1 shims after the crossover achieve this?
This is the stack I used:
BV (unchanged from the last ride):
23.1
14.1
23.1 (3)
20.1
18.1
16.1
14.1
12.3
MV:
24.1 (2)
12.1
24.1 (2)
20.1
18.1
16.1
11.2
Rebound:
23 x .1 (3)
20 x .1
18 x .1
16 x .1
12 x .15
10 x .3
13 x 2.15 washer (2)
2 x 1.2mm bleed holes in piston - closed using JB weld.
I also added 1mm of pre-load to the rear as on the last ride it felt like the front was slightly stronger then the rear. I played with too much at once, within the first hour of the ride I had to take the pre-load back off the rear, it turned everything to poo. With pre-load back to approximately 10mm the rear felt good again.
Now last valving stacks I was pretty happy with the front, it was super plush and apart from diving under brakes and falling slightly through the stroke on braking bumps they were good, slightly mushy but the best I've had them so far. Rebound was also far too quick, both high and low speed.
First up the rebound has improved somewhat by adding the face shim and filling in the bleed holes however it could still be a little stiffer. It was wet and slippery on the weekend on the front had a tendency to push down off-camber sections and push wide through corners. High speed was similar and it would start to pogo on downhill sections with lots of drop-offs and rocks.
Adding 1 face shim to the MV and reducing the float by .1mm has made a huge difference, and not for the better. It has stopped the forks from diving under brakes and they sit nice and high in their travel, so that bits' great. But I think the stack is now too stiff as they aren't as plush anymore and square edges once again jar (not nearly as much as the stock stack). I was also getting some deflection, most noticeably on angled tree roots and wet rocks, then again it was wet as mentioned so this could have contributed to the problem.
I'm also wondering if the MV is now too firm and pushed oil through the BV leading to cavitation on fast deep compressions such as steep downhills with ledges and rocks etc. As mentioned the forks began pogo-ing and they didn't do that with the previous MV stack.
I plan on firming up the rebound stack a bit more, not sure yet as to add another face shim to slow down the low speed and initial opening or add a larger clamp shim to firm up everything. Any thoughts?
The MV has me stumped, I really want something between the two stacks I have just used, one that prevents diving and falling through the stroke like the current stack but retains the plushness of the previous stack. Would removing one of the 24.1 shims after the crossover achieve this?
Re-valved the front again:
This is the stack I used:
BV (unchanged from the last ride):
23.1
14.1
23.1 (3)
20.1
18.1
16.1
14.1
12.3
MV:
24.1
12.1
24.1 (2)
22.1
20.1
18.1
16.1
11.2
Float = 0.5mm
Rebound:
23 x .1 (3)
16.1
23.1
22.1
20 .1
18 .1
16 .1
12 .15
10 .3
2 x 1.2mm bleed holes in piston - closed using JB weld.
I removed a face shim from the MV stack and added a shim in the HS stack to keep the float at .5mm.
Also beefed up the rebound a fair bit.
My first ride was through techy single with some evil root infested hills and a mean mutha of a rocky hill section. All of it was the slipperiest terrain I've ever ridden.
Following a few mid track adjustments to rebound and compression I think I'm pretty happy with this suspension at the moment. It was perhaps slightly too firm in the initial part of the stroke but it was very very hard to judge in the conditions. It was so slippery I had to all but close the rebound clickers to stop the front from washing out, I even had to add 4-5 clicks of rebound to the rear which I've always been very very happy with.
Overall it seemed to eat up the angled trees across the track and square edged hits and that was in the wet. Prior to declaring this stack a success I need to test it in the dry, but so far so good.
This is the stack I used:
BV (unchanged from the last ride):
23.1
14.1
23.1 (3)
20.1
18.1
16.1
14.1
12.3
MV:
24.1
12.1
24.1 (2)
22.1
20.1
18.1
16.1
11.2
Float = 0.5mm
Rebound:
23 x .1 (3)
16.1
23.1
22.1
20 .1
18 .1
16 .1
12 .15
10 .3
2 x 1.2mm bleed holes in piston - closed using JB weld.
I removed a face shim from the MV stack and added a shim in the HS stack to keep the float at .5mm.
Also beefed up the rebound a fair bit.
My first ride was through techy single with some evil root infested hills and a mean mutha of a rocky hill section. All of it was the slipperiest terrain I've ever ridden.
Following a few mid track adjustments to rebound and compression I think I'm pretty happy with this suspension at the moment. It was perhaps slightly too firm in the initial part of the stroke but it was very very hard to judge in the conditions. It was so slippery I had to all but close the rebound clickers to stop the front from washing out, I even had to add 4-5 clicks of rebound to the rear which I've always been very very happy with.
Overall it seemed to eat up the angled trees across the track and square edged hits and that was in the wet. Prior to declaring this stack a success I need to test it in the dry, but so far so good.
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