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Discussion Starter · #1 ·
I pulled the trigger and got Manitou Tower Pro 29" 80mm for mere ~$250+tax: Manitou Tower Pro 29er Fork | Manitou | Brand | www.PricePoint.com

I put it on my bike, set recommended air pressure, and... it bottoms out from a simple bunny hopping! :(

What am I doing wrong? My weight is 165lbs - recommended pressure is 70-90PSI. I have it at 90PSI. Sag, when I sit on a bike, is around 30mm. I haven't tried higher pressure yet as my pump maxes out at 90.

Worst case, any recommendations for LBS in Bay Area that deal with Manitou and could service this fork?

Thanks for all the tips I can get.
 

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Correct! You need a shock pump. After that, this may help too...

The Tower Pro uses our MARS Air system. MARS air uses a small coil spring in series with an air spring. The coil eliminates all felt stiction created by the seals in the air spring. But more than that, the properly tuned MARS system has 3 distinct rate curves over the full travel. The initial rate will be determined by the coil spring. Then from about sag to 70% of travel, the rate curve will flatten out as both the coil and air spring work together. Then late in the stroke, the air spring will dominate and ramps up in a progressive fashion. In other words, the entire range of stroke can be optimally tuned without sacrificing the other areas. A full air system, for example, trades off mid-stroke vs bottoming feel depending on the air volume used. A larger volume will provide a more linear feel though-out the mid-stroke, but lacks bottoming control.

Tuning the MARS Air requires a couple of pieces of information:

1. If you can not reach desired sag regardless of air pressure, then you need a firmer coil rate.

2. Too much air pressure will create a distinct spike in the mid stroke because the air spring is too dominate over the coil. If this happens, you will want to install a higher rate coil. In a (model year 2012) Tower Pro, which come stock with a “Firm” coil, this will occur around 120psi. We call out 110psi MAX in the Tower Pro, but there is some margin in that number. As long as you know what to look for with the above two points, you can creep up towards that 120psi.

Now, if you have sag set to a value you are happy with (maybe 25%, for example), but find yourself bottoming too often, you can increase the bottoming resistance by adding about 5cc of oil to the top of your air piston. (Let the air out first before unthreading the cap!!) This will make the last portion of travel more progressive.

Another tip: If you have too much brake dive, you have a few choices. Add another 5-10psi (sag percentage is only a starting point anyway), try a firmer rate coil, add that 5cc of oil on the air piston, or add a click or two on your ABS+ compression adjuster.

Keep in mind, the spring determines HOW MUCH brake dive, the ABS+ compression system determines HOW FAST the brake dive. The reason people tend to use compression damping is that when the fork dives more slowly, they naturally adjust body position more easily to compensate for that dive, often without even realizing it. The downside is they often sacrifice ride quality in the process.
 

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Discussion Starter · #4 ·
Wow, thanks for quick responses!

Yes, proper shock pump is on its way. (I pumped the shock like crazy with my tiny trail pump and then measured the pressure with a separate digital pressure gauge at 92.2PSI).

Following maettu's suggestion, I'll pump the shock more and see how it feels. I guess I need to be more patient until the pump arrives. Thanks!
 

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There is such a low volume of air inside the shock that you are probably losing a lot of pressure each time you check.

Also word of advice, never make adjustments to the pressure without your shock pump. The smallest tap to the valve releases a lot of pressure. I usually carry my shock pump with me when I first get a new bike/shock so I can fine tune it while riding until I am happy with it. After that, just leave it alone.

It is best to always use the same pump if you can because a different pump might read slightly different. Lastly when remove the pump, don't worry about the sound of air escaping. It is just the air in the pump.
 

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Great post maettu! Everything he said in there is true, when I got my 2011 and installed the FIRM spring (mine came stock with a MEDIUM) it took me a couple weeks of rides, playing, etc to get it fine tuned but once I did I have not touched it since!

There is a great thread about tuning the fork around here (specific to clydes) and has some great suggestions. If nothing else, you can contact Manitou, their customer service is exceptional and they always have great suggestions.
 

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FYI am 165 with a 120mm fork. I like mine just above 75psi. I also find for me it performs better about 3 or 4 clicks from wide open on the ABS+ knob. If I am going down some serious jumps drops, or really nasty rock gardens I will increase that by another click or so.

I'd try to get it dialed in first but you can also play with the shims in the ABS+. You can rad up on it here. I think the ABS+ shim manual is a page or two into it. If not I can post a copy Manitou sent me.

http://forums.mtbr.com/shocks-suspension/how-guide-reshim-your-abs-hsc-shim-stack-687754.html
 

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Don't listen to Matt. His beer gut alone weighs 165 lbs.
 

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Discussion Starter · #9 ·
Matt, does it easily bottom out when it's fully open and at 75psi?

I'm trying to get my expectations right. I have a 26" Manitou Match, which, when ABS+ is fully open and spring pre-load set to most firm, bottoms out only on very serious drops. I guess I'll just wait for the pump, set it to 110psi and see how this fork behaves.
 

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Matt, does it easily bottom out when it's fully open and at 75psi?
Because I ride with him quite a bit, I can say that I don't think it has ever bottomed out on him and if it has, not easily.

I have the Tower Comp 29er on my SS and was running 75 lbs but ran it up to 80 lbs because I like a stiffer suspension. I am 185 lbs (200 lbs with gear and clothing).
Now that is my single speed hard tail and I am not quite putting it through the work that my full suspension goes through but still I don't think it would ever bottom out unless I really hit something big.

Run it by your local lbs and see if you can borrow their shock pump for a second.
Put 75-80 lbs in it and ride it. Then when your pump arrives you can work on fine tuning it.

I will bet that when you put a shock pump on it, you will probably find out that you don't have the air pressure you think you have in it.
 

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Discussion Starter · #11 ·
Okay, I got a pump and pumped the shock up. At 110psi I get ~10-15mm of sag, but...

At the same 110psi, if ABS+ is fully open, I can hit the bottom with a simple bunny hop, just putting some weight on the front. Even after 6 clicks to close ABS+ --- if I try a bit harder --- I bunny hop to the bottom :(

It really feels too soft. I have 26" Manitou Match on another bike, which does not bottom out on me. I also had a few demo 29" rentals over the last year, mostly with Fox forks - none were so easy to bottom.

What do I do next? Should I try adding 5cc oil as a recommended hack by maettu? Or go straight to LBS? (Any recommendations for Manitou friendly LBS in Bay Area?)

Thanks a lot for all the help so far!
 

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Call Pricepoint and see if they will exchange it or Manitou to warranty it.
 

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Yeah, that sounds too soft at that pressure. I think the highest I have pumped mine up to was around 90. That said I do find it quite "supple" when the ABS is fully open. Not near as stiff as a Fox. Though I like its suppleness. I know I don't bottom out when I am doing casual riding but I do use a lot of its travel. I have had it "collapse" on me a couple of times when running pressure down around 65 psi. I can test it out a bit this evening, check the psi and make note about how much travel I am using for different situations.

I don't think pricepoint will exchange it as it may not be an issue the fork. Either way they would probably refer you to Manitou. Go to their website and submit a support request via their form or give them a call.
Contact Us | Hayes Components

I had some setup questions, and to some extent the same issue you are having as I perceived me going through the travel too quickly. Their support was helpful and fairly prompt. I have to say better interaction and customer service than I have had with a lot of other companies. From my emails with them it sounds like you may need a stiffer spring. I don't know which one is in mine but maybe mine came with a stiffer one than yours. While I haven't taken mine apart yet, all the videos I have seen they look quite easy to work on. I don't know your comfort level with the mechanics of forks but don't do anything you aren't comfortable doing with.

I will paste some excerpts of my communication with them below.

________________________________

Q:
Hi,

Overall I am happy with my Manitou Tower Pro but I'd like to dial in the ABS adjustment. I'm not sure what I want to be able to do is possible but hope it is with the shim kit.

What I hope I can change is two part.

1. The max lockout platform blow off requires a bit too much force for my weight. So I want to be able to "soften" the platform. I know that can be done. If I'm not mistaken that would be a smaller platform shim.

2. To me it's seems there is not much range of stiffness as you increase the ABS dial towards the max platform. So basically I as I move it towards max platform I would like there to be a more noticeable stiffness or reduction in velocity as I move towards the max platform. It just seems to me that there is very little to no difference between fully open and 2 clicks from being at max platform.

In regards to number two, this is just my perception, nothing measured or scientific. Looking at the shim guide the stock production XC should be more stepped that what I am observing. Looking at that guide I am thinking the trail shim stack and a bit more oil would be better for the rooty and rocky trails I ride. Geared up my average weight is probably around 177. I also ride pretty aggressively. Still trying to find the sweet spot. I love the plushness at lower psi but I have had the shock collapse on me and OTB. Higher pressures obviously fix that issue but I'd like to find that sweet spot where it is plush fully open and I can dial up the ABS before I hit more technical sections. I just have to remember to adjust.

I will end up going ahead and getting the shim kit and doing some experimenting but any advice would be welcomed.

Also where can I order the shim kit?

A:

here is our ABS+ tuning guide.
All you may have to do is remove one shim for the shim stack to achieve a lesser platform.

What air pressure do you currently ride with?
Depending on the air pressure I may suggest to change out the spring as well.

Tuning unfortunately is not straight forward and will take some time playing with different tunes to find the one that suites you.

I would recommend changing only one thing at a time this way if you don’t like the way it feels you can easily go back and change it without playing the guessing game.

Q/Response:
I have been trying different air pressures and it seems that right around 70 is the sweet spot for me if I add 3 or 4 clicks to the ABS. I have to be careful though as if I am doing some real step technical section or if my weight gets over the bars and fork I find I can go through most of the travel and the fork "collapses" on me. Of course if I add more pressure that fixes that issue but I don't find the fork as quite as plush and small bump compliant. At least that is my perception, as I know the spring is the primary function for the small bump compliance.

After reading the tuning guide I think I could maybe benefit from the trail tunes. Several of those look intriguing especially the CV-11811-07, EK-012611-02, and the CV-11311-01.

Do you sell the shims or can you refer me to a dealer who does?

Open to suggestions. Like I said I am overall happy with the fork, but feel given all the options available I could really get it dialed in for my style of riding.

A:
if you send me your address I can send off some shims to you so that you can play with a few tunes.
I do not have a source that sells the shims.
We only offer it in a large kit for service centers and shops.

You are at a low enough air pressure for me to think the spring is the correct one.
I find when people are maxing out the air pressure or close to changing the spring to and stiffer one is a good option.
 

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Discussion Starter · #14 ·
Just a quick update.

Talked to Manitou support. They looked up my fork's serial number and figured that the build has a soft spring in it. I'm ordering firm and extra firm spring kit to experiment with. I'm sure one of those will work for me. Thanks for all the help folks!
 

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At 165 I highly doubt you will need the FIRM let alone the X-FIRM.. I have my old medium spring that I am happy to send you.

Just for note: I am 190ish and run the firm with 75-80psi depending on how progressive I want it... I have been leaving it at 80psi as of late and love the feel, I have NEVER hit bottom even hucking a 3' drop on accident.
 

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Are you talking to me?!
If so I was able to find it by hunting ebay, also remember this was 3yrs ago almost (think I bought the fork in late 2011 after my RST M-29 gave up a seal) and was at the end of the riding season so not that hard to find deals around that time. You will usually see prices drop around the time of Interbike/Outerbike.
 

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Sorry I should have been more specific, I was referring to OP!

Valas - When and how did you get that deal? looks like its close to 400 right now

I pulled the trigger and got Manitou Tower Pro 29" 80mm for mere ~$250+tax: Manitou Tower Pro 29er Fork | Manitou | Brand | www.PricePoint.com

I put it on my bike, set recommended air pressure, and... it bottoms out from a simple bunny hopping! :(

What am I doing wrong? My weight is 165lbs - recommended pressure is 70-90PSI. I have it at 90PSI. Sag, when I sit on a bike, is around 30mm. I haven't tried higher pressure yet as my pump maxes out at 90.

Worst case, any recommendations for LBS in Bay Area that deal with Manitou and could service this fork?

Thanks for all the tips I can get.
 

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Discussion Starter · #19 ·
intechrity: There was a deal at PricePoint, here is from my receipt:
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1 315 MAN152 MN8 Manitou Tower Pro 29er QR 80 TAPER 249.98
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I just got lucky, or maybe not so much.... The thing is that fork is super soft even at 110psi and all firm and x-firm ride kits for 80mm are out of stock. There is no stock in online stores and my LBS confirmed that it's out of stock at Manitou themselves and I should check with them a few weeks/months later. Until then, I ride this fork at 110psi with heavy compression dampening, which does not feel good at all.

Gregnash: thanks for the offer. Is yours 80mm fork? Let me see if I can just find medium ride kit online (I think I saw some). The kit is not that expensive and would save you shipping hassle. If I can't find medium kit, I'll send you PM. Thanks again.
 
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