Naw the air shelf has nothing to do with that. I'm assuming you ratchet the strap again after that 2mm gain? Did you use an impact gun or a drill? Something that can spin it faster that your hand is needed.

 

Aha, thats good news, read in the manual that it requires sending it away for service if it has moved.
Yep, tried to tighten it further, but it didn't seem to compress further strangely enough.
No, only hand tools here. I'll see if I can borrow a power drill, maybe thats solution. Thanks.

 

Stratus,

Keeping raising the air until you get the level of support you seek. There really isn't a max air pressure, but what will happen is it will develop a harsh spike in the spring curve if the air springs gets outside of the compatible range of the coil spring. I'm 165lb, and currently running a med spring with 110psi in my TP.

Check out the Tower Pro thread. Lots of good info there on setting up the mars spring. It can be quite confusing. Don't fall into the trap of thinking you need a firmer spring to get more support. The air spring portion is really what shapes the mid/btm support, and imo the charts on the fork legs aren't even in the ballpark, especially if you are an aggressive rider.

 

Does the blue rebound adjustment knob on the minute pro supposed to have "clicks" when you turn it? I'm used to having click and new to this minute pro. Also where is a link for the different dump charts for the different shim stacks? The one i found didn't work. Thanks all. This afternoon should be my maiden voyage on the fork and I'm stoked.

 

No it's not indexed, so no clicks. Continues over 180 degrees.

The link mentioned in the beginning is dead, the working one is somewhere in here.

 

Stratus - I had same problem. I managed to unscrew the bolt by pumping up the pressure first, so the compression rod in the air spring is pressed tightly against the bottom of the leg. I was still unable to unscrew it by hand. I took a ring spanner and put it over the bolt head, then took hammer and hit the other end of the spanner to make it rotate. It's like improvised impact gun Took two or three hits to make the bolt rotate inside the rod. I hope my explanation was clear - don't hit the bolt with the hammer, but use the hammer instead of your hand to make the spanner rotate.

Regarding the pressure and spring. I think the correct procedure is to add more air until you like the mid stroke and don't get too much brake dive. If you bottom out at this pressure too much, add some grease into air chamber to make the spring more progressive. If after those adjustments the small bump compliance is bad you need softer spring.

I'm 220lbs, and ride 100mm Tower Pro. The weight distribution is ~35/65 - this is important. I use ~100psi and medium spring. I had firm spring first, but for my riding (lot's of small roots, no jumps, very small drops) it felt too harsh. I had one ride with medium spring and it seems good. I also made the shim stack much softer. I have bunch of shims, so I plan to play with different configurations.

 

Stratus - I had same problem. I managed to unscrew the bolt by pumping up the pressure first, so the compression rod in the air spring is pressed tightly against the bottom of the leg. I was still unable to unscrew it by hand. I took a ring spanner and put it over the bolt head, then took hammer and hit the other end of the spanner to make it rotate. It's like improvised impact gun Took two or three hits to make the bolt rotate inside the rod. I hope my explanation was clear - don't hit the bolt with the hammer, but use the hammer instead of your hand to make the spanner rotate.

I found a topic on here regarding this problem, the hammer and spanner approach was suggested there too. I tried it, but still no luck sadly. Kinda running out of options I'm afraid. Thought about griding the bolt head of.

 

http://forums.mtbr.com/29er-components/manitou-tower-pro-fork-clydesdales-techical-751708.html lots of good info in here, even if you're not a clyde. i'm sure its been posted before.

arnea that to me seems crazy, but if it works it works.

 

It does work and that's how it supposed to work, but it's hard for folks to uderstand. The Tower Pro thread does a much better job of explaining how the coil and air spring interact in the Mars setup. The Clyde thread . . . not so good, unless your 250+ lbs because it mostly promotes "the firmer coil equals more support" misunderstanding.

 

http://forums.mtbr.com/shocks-suspension/tuning-tower-pro-852107.html

 

BTW, I put the ABS+ tuning manual up here: http://home.cyber.ee/arne/ABS+ Tuning REV 3-10-2011.pdf

 

yeah i've read most of TaTP and literally all the crayon bell graphs make me sleepy. even you were back and forth on firmness of coil and air and what coil to use. so when my new lowers to arrive (found a crack at rebound knob upon an overhaul) i will install the firm spring and run higher psi to refresh my memory. i'm not trying to ruffle feathers as it's been a while since i adjusted internals. i do see what you're saying to an extent. i just got back into the sport 3 seasons ago. last manitou fork i had was back in 95 and used polymer bumpers.

here' my setup

200#'s geared, sag at about 25% in attack mode with xfirm spring. 95psi, 5 clicks from max, rebound ~90% open, 5cc grease top side. bottom out 1-2x's a ride. trails consist of roots, rocks, average drop 2-5 feet couple times a ride with occasional jumps with good transitions

when i run the firm spring what psi should i start with? i believe i'm riding this fork at it's limits and might want to look at a more AM fork but can't swing that at the moment

 

yeah i've read most of TaTP and literally all the crayon bell graphs make me sleepy. even you were back and forth on firmness of coil and air and what coil to use. so when my new lowers to arrive (found a crack at rebound knob upon an overhaul) i will install the firm spring and run higher psi to refresh my memory. i'm not trying to ruffle feathers as it's been a while since i adjusted internals. i do see what you're saying to an extent. i just got back into the sport 3 seasons ago. last manitou fork i had was back in 95 and used polymer bumpers.

here' my setup

200#'s geared, sag at about 25% in attack mode with xfirm spring. 95psi, 5 clicks from max, rebound ~90% open, 5cc grease top side. bottom out 1-2x's a ride. trails consist of roots, rocks, average drop 2-5 feet couple times a ride with occasional jumps with good transitions

when i run the firm spring what psi should i start with? i believe i'm riding this fork at it's limits and might want to look at a more AM fork but can't swing that at the moment

I wouldn't say I was back and forth but it took me awhile and testing 3 different coils before I found a setup that had good mid support and small bump. I didn't fully understand what was going on until I modeled the spring curve and could play with all variables. I had to switch from a soft to med spring because I got to that point where the coil was harshly bottoming before the air piston started to move. Before I went up on air, the fork was carpet ride plush but had terrible mid/btm support. Depending on how you ride and at what level, that might work for you.

It's really hard to compare spring setup based on rider mass. If you want to try a firm spring, just guessing, I go up 15-20 psi and just tune by feel. This is also a hard conversation to have without factoring in damping. You can run a ton of damping to get good mid/btm support with a soft spring but it be terrible at absorbing square edge.

***edit*** If you are already at 25% sag with the the xfirm, the firm will probably be too soft, but don't let that keep you from trying it. Judging by how you described your riding style, I'd say you won't like it.

Sorry but not a misunderstanding, the engineers that designed and test the fork say that's how its to be done so air pressure doesn't overcome the spring. Its not a simple negative spring air system.

You have to take that in context of the clyde thread and everything trailbuilder posted from the Manitou Engineers was specifically for the clyde spring. If you recall, he ultimately had to go up on both coil rate and air to get where he needed to be. You can definitely get to the point that the air over powers the coil, but like I noted above it's much higher than that worthless chart on the fork leg. Even Manitou published curves of the clyde spring with 190psi. I also talked to Manitou through out my hole testing, they told me to run firm/xfirm based on my weight. They changed their tune the more we talked and I shared my test results.

The air spring predominately defines the mid/btm portion of the curve. Coil defines sag and mostly effects small bump and the initial portion of travel. That's the short. Don't knock it until you try it.

Anyway, back to abs+ tuning. I have had this same beat my head on the wall discussion more than once on the TP tuning thread.

 

There is one more non-destructive option as described here:

http://forums.mtbr.com/shocks-suspension/some-days-just-suck-853791.html#post10381378

I haven't tried it myself, but you should be able to remove the piston (compress the fork fast and it should pop out) and then push long 5mm allen key from the top of the fork, down through the blue rod. The end of compression rod has 5mm allen head. There is black rubber plug on top of blue rod, you should push it out with the allen key.

 

Can anyone tell me what the weight difference between the marvel pro 80/100 and 100/120 version is?

 

I have the expert version which is 60g heavier (if you get pro with steel steerer) only because of damper, its in the stancion instead of separate cartridge in the stancion. Also can adjust 80-120 on the fork adding/removing spacers, im guessing damper cartridge is limiting that part but can't be more than 10-15g difference in the 2. 20mm more travel in damper but less spacers compression side. Not enough you or anyone else would ever be able to notice.

 

I assume you mean the expert is +60g on the pro? The Manitou tech said the 100mm can be internally adjusted to 80mm but not to 120mm and the 120mm version can be adjusted to 100mm.

 

The Manitou tech said the 100mm can be internally adjusted to 80mm but not to 120mm and the 120mm version can be adjusted to 100mm.

The 80/100mm version has a different Compression Rod Assembly and a different CSU to the 100/120mm version.

Travel adjustments are made with internal spacers: http://www.manitoumtb.com/wp-content/uploads/2014/01/2014-Aftermarket-Fork-Travel-Adjust-Guide.pdf

 

Ya must be different on the pro because of the damper cause my expert (just bought last August) I can go to either extreme, box included extra spacers and was preset at 100.

 

The 2 spacers are to reduce the travel by 10mm each, to 90 or 80mm travel.
I didn't think the 100mm forks could be lengthened though?

 

My 29er version goes all the way either direction, 80-120. I can stuff in a max of 4 spacers to get 80, only 2 in is 100, take them out its 120. I dunno why mine is different but I paid the lbs price to make sure I got absolute latest version so offset was 48 etc. But odd only expert can do this.

 

Ill open mine up and let ya know when they arrive I got the 120s

 

Any youtube vids on adjusting the travel? Can't seem to find any. Found the tech doc http://www.manitoumtb.com/wp-content/uploads/2014/01/2014-Aftermarket-Fork-Travel-Adjust-Guide.pdf
but it's nice to see it done too, cheers

 

Its really simple if u just read the instructions on the doc, just make sure to turn the ring for the rebound damper adjustment the right way when you pull the lowers off, it snaps off easy if you do it wrong.

 

Got the fork on the bike, I weight about 85kg (188lbs) with pack etc. I know the fork will loosen up as it wears in just curious what air pressure others are running on the marvel pro 120. I've got it at 70psi atm with the rebound around halfway.

 

Pressure is rider/bike specific for say and feel. Pressure number actually means little because every shock pump is different. Use sag to sort out air pressure, once u dial it in record the pressure ur pump says so u know for next time.

 

Still no luck removing the bolt, but haven't really tried either. Haven't had time really, but managed to get a few rides in. Most of them on road for training purposes, but a bit offroad aswell, with the pressure just exceeding max (...) the brake dive was a bit more acceptable, but the transition from coil to air seemed to be too noticable in a negative way. The damper didn't seem correct that either, running close to max it felt both wallowy and jerky.

But one of the reasons to pick up this fork was the ability to easily tune the damper yourself, hence this topic. But as is mentioned (wisely) in the beginning of the topic, spring rate trumps damping, so I thought to get that in order first. But since the fork doenst want to let go of its lowers that isn't going anywhere soon. Someone pointed out earlier to me, not to try and get a higher spring rate, as in the Tower Pro tuning topic, quite a few heavier riders found that not to be what they were looking for.

So last week I decided to open up the damper after all and take another look at the tuning guide. Read the descriptions with the various shim stacks, kinda knew what I was looking for and what was possible with the standard shim stack (stock trail) and no additional shims. That doesn't leave all that much options, but one stack looked interesting, so I took out the speed shim and with two platform shims you ofcourse get the stock xc stack.

Haven't had time yet to take it for a good ride, I did try it out in the street quite a bit and on some 'obstacles' and it seems promising. The excessive brake dive is gone and the fork stays up in it's travel and there is a lot more support along the way, mid stroke especially. Full open to five clicks from max feels good, any clicks more to max makes it feel too harsh, but the pressure was still high at that time (Sag was too low, so that's a giveaway). Dropped the pressure to more normal values and hope to try it out on some trails soon.

One thing I noticed opening up the damper, was that my compression piston is blue, on all the photo's everyone elses is red. I thought I did see a blue one in the Manitou shim kit. Any logic behind that?

Thanks.

 

Still no luck removing the bolt, but haven't really tried either. Haven't had time really, but managed to get a few rides in. Most of them on road for training purposes, but a bit offroad aswell, with the pressure just exceeding max (...) the brake dive was a bit more acceptable, but the transition from coil to air seemed to be too noticable in a negative way. The damper didn't seem correct that either, running close to max it felt both wallowy and jerky.

Dude, there is no max pressure so to speak. Pull that sticker off the lower and throw it away. How much air are you running? My dad is the same weight (just for reference) and I have him setup with a firm spring (120) and 120 psi. I highly doubt you are feeling the transition from coil to air.

Damping setup is a personal thing. IMO, the xc stack is a mistake unless you want an ultra firm lockout at the sacrifice of small/square bump performance.

 

Omg dont do xc stock stack, im 275 and that stack was rough.

Get ur spring rate right them rip out a platform shim, turn knob to 3-4 clicks open from lock. Brake dive goes to almost non existent but doesn't beat the crap put of you. Your actually approaching it backwards from what the tuning guide says to do.

 

Btw the 19mm shims are platform shims so the more you add the stiffer and rougher the damper is going to be. Its better in most cases to use less (most only use 1 19mm or add the tension relief shims between the 17mm and 19mm) platforms shims and use 17mm "speed shims" to control most of the damping curve. Its the knob that controls brake dive and pedal bob more. Closer to lockout, the less there is, but more your reliant on the shim stack being tuned properly so your not feeling like your on a rigid fork.