RASE Black Mamba Rapid Adjust Dropper Seatpost

3.74/5 (19 Reviews)
MSRP : $379.00

Product Description

The patented Black Mamba Rapid Adjust Seatpost instantly raises or lowers "on the fly" up to a full nine (9) inches and locks securely into place at all intervals, providing the rider with the ultimate in power and control when faced with tackling challenging and variable terrain. The Black Mamba is simply operated from a remote lever on the handlebars and takes just minutes to install. Constructed of lightweight but incredibly strong 7075 Aluminum, the Black Mamba is built to sustain even the most gnarly descents and the steepest climbs ride after ride.

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Reviews 1 - 15 (19 Reviews Total) | Next 15

User Reviews

Overall Rating:4
Value Rating:4
Submitted by L84thsky a All Mountain Rider from Amityville, NY USA

Date Reviewed: March 3, 2012

Strengths:    Drops 9 inches, built very strong, MADE IN USA, very high quality components. Pin lock selection of adjustment, with 20 settings. No air pressure to leak out.

Weaknesses:    Does rattle as others have stated, but to be honest, who cares. If I'm blazing through a rock garden and my organs are bouncing around like Mexican jumping beans, do I care if the seat makes noises? My biggest complaint has to do with mounting the cabling to your bike.

Bottom Line:   
The best built and the most durable post on the market. This is American quality at it's finest. You are not going to please everyone. Because of the geometry of my bike, flexing the cable to route on my center tube was an issue. In the end, I had my machine shop make an adapter that connects to the point the cable exits the seat post. This allowed more of the cable end to seat deeper in the post. Then I used a small piece of cable to make an S bend, and terminate this cable into a cable guide. In between the two cable guides, I used exposed wire. Then I used another piece of sheathing to go from my front cable guide to the lever. Works great for me, and I even showed my design to RASE, and they said it was fine.

People have complained about the lever being too short. They make two different length levers. I bought the longer lever, and intended to use it as a thumb actuated lever. That worked ok, but it forced me to extend my thumb and therefore have less grip on the bar. I've since then swung it around, and use my index finger to actuate the lever. Much better since the index finger can reach the lever and my hand feels better planted on the bar.

Those who complain about a single bolt holding the seat just wanna make something out of nothing. That is unless they weigh 200+ lbs and drop off 10ft rocks all the time. The clamp is strong, and the bolt is too.

The bar drops and raises without any real issues. Sometimes, I may drop it an inch or two, then want it fully up again. Remember, the more the spring is compressed, the more force it can push up. If I am concerned the seat won't go up the last two inches, I simply, squat on the seat a few more inches, lift up and press the lever. The beauty is, you can hear when the seat post is fully extended, it's like the sound when an umbrella opens. You hear the mechanism smack the end stop.

Rated 4 chilis for value, due to it's price
Rated 4 chilis for overall, due to the extra work to make it fit my needs.

Expand full review >>

Favorite Trail:   Blue Mt, Peekskill NY

Duration Product Used:   1 Year

Price Paid:    $359.00

Purchased At:   Company Website

Similar Products Used:   KS i950

Bike Setup:   Turner 5 Spot, Magura Thor fork, Rohloff Speedhub, DT Swiss XR Carbon rear shock, Mavic 819 rims with UST Hutchinson tires.

Overall Rating:5
Value Rating:5
Submitted by santana a All Mountain Rider from wallingford ct

Date Reviewed: February 17, 2012

Strengths:    It works. Seat goes up and down as required

Weaknesses:    none really love it, just a thought if the cable came at 90degrees it might look neater on the bike. I have not had any issues with the cable yet.

Bottom Line:   
I have a 36 inseam. My seatpost was always in the way before the black mamba. Keeping my chest in the seatpost for big drops was bad. Just starting my third season on new england rocks and roots. I had been riding a bike for 50 years before starting on the rocks. The black mamba let me put the seat all the way down for big drops and descents, somewhere in between for rock gardens, on long climbs i can lift it to the height that I would keep a road bike seat. It makes me feel a lot more confident on the bike and gives me the option to learn to pump the bikes suspension through the corners and over stone walls. You can rest with both feet on the ground. I lube it ever few weeks. The cover that the stem comes with keeps the stem clean enough so that I do not have to clean it. Just spray the seat and spray the chain and velcro the cover back in place and go. I would not ride without it. Sure their customer service is no contact but I was not looking to friend them on face book I just need a seat that drops. As far as rattling it moves a bit but around here we wear full body armour and full face helmets and we bounce off of rocks and trees constantly so it is not an issue. I am probably the worst rider in the group but would like to note that the best rider ( cat 1 ) uses a dropper seatpost and makes atjustments constantly. He uses all the way down for jumps, up for climbs, middle for rock gardens he set his so up with one also. Black mamba is the way to go.

Expand full review >>

Favorite Trail:   Gray ville

Duration Product Used:   1 Year

Price Paid:    $375.00

Purchased At:   rase

Similar Products Used:   none

Bike Setup:   Had it on my titus racer x titanium L, now on a santacruz tallboy xl, rockshox xx 20mm, Fox float rp23 , maxxis 2.4, stan ZTR flow . Seat trigger on the left handlebar.

Overall Rating:1
Value Rating:1
Submitted by Ledgeview a Downhiller from BC

Date Reviewed: December 19, 2011

Strengths:    No idea. Never received my order.

Weaknesses:    No clue. Never received my order.

Bottom Line:   
I ordered the Black Mamba because i was impressed by the no hydraulic spring mechanism and 9" of travel. Not the cheapest product at $355 USD plus delivery. Delivery should have been 7-10 days as advertised. RASE promptly charged my visa and made me wait 2 months! But after 2 months of never being able to reach anyone (they never answer the phone) and countless emails and BS excuses like "we have excessive orders at this time and your order is delayed" to "we have lost our main component supplier due to the poor economy and are now sourcing new suppliers and would rather loose an order than ship an inferior product", excuses, etc, etc, on and on. They promptly cancelled my order without my consent and reversed the charge on my card. Yet l'm left with an interest charge after 2 months. RASE has some internal company issues relating to customer service and supply chain that they need to over come. Brings their products into serious question. RASE customer service plane sucks. ln hind sight, i am glad i didn't receive the Black Mamba. I cant imagine what after service and support would have been like. CAUTION, buy this product - you take a huge risk that RASE goes under and you are left with something that cannot supported or serviced.

Expand full review >>

Favorite Trail:   Paper Route

Duration Product Used:   Less than 1 month

Price Paid:    $355.00

Purchased At:   Rase on line

Similar Products Used:   I ordered a RockShox Reverb for $325 USD and no charge for shipping. This is what l should have ordered from the start. Units are in stock and delivery is 5 days. How can you go wrong with products and service from RockShox? A company that has been around for 20 years.

Overall Rating:3
Value Rating:2
Submitted by Rockymtnrider69 a Weekend Warrior from Denver

Date Reviewed: August 17, 2011

Strengths:    Raises / lowers quite well. Pin-in-hole design is mechanically simple, no seals to wear out as with pneumatic designs.

Weaknesses:    * Weak saddle clamp, slips.
* Your effective travel may very well be less than the stated 9" of adjustment range (see comments below).
* Needs a little maintenance (clean and lube inner post frequently)

Bottom Line:   
My first adjustable seatpost, I like it, it does make trail riding more fun. Some reviewers indicated problems with it going up properly or making noise, I have not experienced those problems, mine pops up just fine.

I would have give it a 4 if not for the single-bolt seatpost clamp. If you are a larger rider, or sometimes take some hard jolts while in the saddle, the saddle may slip nose-up or nose-down. And when it slips it wears the clamp splines, making the it more likely to slip again. Be sure to check bolt tightness often.

A friend came up with a clever solution using JB Weld, plugging the slot the bolt goes through, then drilling a hole in the "weld" for the bolt. Has worked well so far, though it means you can no longer adjust the saddle nose-up vs nose-down.

But hey, at $350, why can't R.A.S.E. offer a twin-bolt (fore-aft) clamp like Thomson and a few others? I have never had a problem with a twin-bolt clamp.

The post is designed with 9" of travel, but depending on your leg length vs bike frame size your effective travel could very well be less. With short legs and a medium bike frame I get effectively 5" of travel. That's good enough for me, just something to consider when you shop.

One minor thing, the manufacturer suggest cleaning and lubing the inner post every ride. I do it more like every 2-3 rides. If your post isn't popping up freely it may need more frequent cleaning and lubing.

Expand full review >>

Favorite Trail:   2 many. Gotta love Colorado.

Duration Product Used:   3 months

Price Paid:    $350.00

Purchased At:   RASE website

Bike Setup:   yeti 575, RP23, Fox 150 air fork

Overall Rating:4
Value Rating:3
Submitted by Steve a Weekend Warrior from Edmonton, AB, Canada

Date Reviewed: July 25, 2011

Strengths:    9 inches of travel with variable height options in between
Excellent conversation starter

Weaknesses:    Only 4 stem sizes available...read on and learn how to overcome the pain of paying big bucks for a product that doesn't fit

Bottom Line:   
When I originally tried to order I was placed on a waiting list, and they got back to me about 9 months later. I'd waited this long, damn sure I was getting one. Now, the issue was the limited stem sizes available, I needed a 26.9 mm for my Rocky, and the smallest was 27.2 mm. It'll fit right? Wrong, wrong, wrong!! I could get the sleeve in, but the shaft bound up and wouldn't move up or down without a lot of effort. Luckily I know a guy at work with a lathe, and 30 minutes later I was in business. Riding with the RASE took a little getting used to, especially having another lever on the handlebars. The seat has a bit of side to side movement in it, but you don't notice when you're riding.

Bottom line : I love the options it gives me as a rider, fully extended for the road to the trail, somewhere in the middle depending the type of trail I'm on, or all the way down for the gnarly hills. No more stopping and adjusting for me, plus it's a great conversation piece on the trail.

My advice is get one, and make sure it fits unless you know a machinist, then occasionally service it by cleaning and lubing the shaft, I use a dry graphite spray that doesn't gum up or attract dust. Have fun!!

Expand full review >>

Favorite Trail:   The one that makes others pause

Duration Product Used:   6 months

Price Paid:    $300.00

Purchased At:   RASE.com website

Similar Products Used:   First one

Bike Setup:   Rocky Mountain ETS-X 30 Trail/Freeride

Overall Rating:1
Value Rating:1
Submitted by griffinsurfboard a Cross Country Rider from Honolulu, Hawaii

Date Reviewed: April 9, 2011

Strengths:    Very well made.
Smooth action.

Weaknesses:    Spring is way too weak and will not raise to the top.

Bottom Line:   
If the spring was stronger as in my Gravity Dropper it would be a great seatpost.
I just tested it on the sidewalk and there is no way i will use it.
It raises about 2" below the top and not as fast to midrange as the Gravity Dropper.
It has some movement in the seat but that is not a bother at all.

If it had a stiffer spring it would be the best for what i want to do but as it is i cant use it.

I hope a different spring is available.

Expand full review >>

Favorite Trail:   Kahuku Motocross

Duration Product Used:   Less than 1 month

Price Paid:    $364.00

Purchased At:   Rase

Similar Products Used:   I have had adjustable posts since 1995
Powerpost then Gravity Dropper

Bike Setup:   Ellsworth Dare with 888 evo fork and Pushed Rocco

Overall Rating:4
Value Rating:3
Submitted by mulchman a Cross Country Rider from Foster City, CA, USA

Date Reviewed: April 7, 2011

Strengths:    9" of travel

Weaknesses:    If off the saddle when it's raised, and going over any kind of rough terrain, it can be very loud from internal spring vibrating. Expensive.

Bottom Line:   
Before getting an adjustable seatpost, and as a 6'5" rider, it was very precarious being up so high on any kind of downhill. I also wasn't a fan of getting jabbed in the groin/chest when getting back/behind the seat for steep downhill sections. Reading other reviews online (and on the mtbr site) I decided I wanted to go with a mechanical seatpost and eventually found the RASE Black Mamba Rapid Adjust Seatpost.

I've ridden just over 100 miles to date with the RASE seatpost and it's been phenomenal and has really boosted my confidence. It's super quick to put down for descents and springs right back up for climbs. (I haven't had issues of it busting me in the balls when springing up, either.)

It does make quite a bit of noise if you keep the seatpost up (at any interval) and are off the saddle; the internal spring seems to vibrate around a lot and it gets quite loud. Also, if you have an XL frame the default cable is on the short side if you try to route it through the frame at all. (They sell longer cables.)

Overall, it has been a great seatpost. Value rating 3 due to expense and overall rating 4 due to not having used other seatposts (so I have nothing to compare it to).

Expand full review >>

Favorite Trail:   Water Dog Lake Park

Duration Product Used:   3 months

Price Paid:    $350.00

Purchased At:   http://rasebike.com/

Similar Products Used:   N/A

Bike Setup:   Specialized Pitch Pro

Overall Rating:4
Value Rating:4
Submitted by BeDVS a Downhiller from San Diego, CA, USA

Date Reviewed: December 28, 2010

Strengths:    Easy set up, easy to maintain and of course the ability to adjust up to 9 inches.

Weaknesses:    Release lever is to short, Pricey.

Bottom Line:   
No issues since I put it on my bike, I lube it every few rides and it hasn’t failed me yet. If you crave the steepest descents and need to get behind your seat an adjustable seat post is a must. For reliability and function the RASE seat post is far and above any of the other adjustable seat post I’ve used. I rate it a 4 out of 5 only because I don’t like the release lever (a little to small).

Expand full review >>

Duration Product Used:   1 Year

Price Paid:    $395.00

Purchased At:   Bike Bling

Similar Products Used:   Joplin R

Bike Setup:   Trek Remedy 8 , Trek Fuel 8

Overall Rating:1
Value Rating:2
Submitted by presslab a Cross Country Rider from Santa Rosa, CA

Date Reviewed: December 19, 2010

Strengths:    Huge range of travel. Nice looking. Ingenious spring design.

Weaknesses:    Rattles terribly when not seated. Sticks and does not return to full height. Metal-on-metal design, no bushing.

Bottom Line:   
This thing seemed like it would be great, unfortunately it made my bike sound like the wheels were going to come off. The post would also not return to full height, I would have to pull it back up. I noticed that only after a couple rides the inner post had gouges out of it.

When I tried to return it to BikeBling I was told "They all do that" and "you used it, you can't return it now." I worked it out through my credit card company (thank God) but it was overall a terrible experience.

Expand full review >>

Favorite Trail:   Annadel

Duration Product Used:   Less than 1 month

Purchased At:   BikeBling

Similar Products Used:   Gravity Dropper, KS i900

Bike Setup:   Santa Cruz Chameleon

Overall Rating:2
Value Rating:2
Submitted by kevin a Cross Country Rider from MARIN CA USA

Date Reviewed: November 7, 2010

Strengths:    gets more travel than you need which is good , can set stops where you want them for less travel

Weaknesses:    sticks after 4 rides does not go all the way back up without pulling on saddle . stubby release lever sucks when compared to crank brothers or gravity dropper release levers . cable guide on post became loose after 1 ride, poor quality , heavy

Bottom Line:   
this adj. seat post is a good idea but it doesnt work well enough for my bike :crappy lever , the spring seems to be very prone to trouble (it has been dry hate to see what happens to it in winter riding ) the part of the post where the cable comes into it widened out on the 1st ride causing the cable to back out and the seat post to slip , fixed that by adj. cable very tight to post and slipping stopped . the post lever is not long enough for me to disengage without thinking of it , my gravity dropper and speed ball posts have much better levers .
RASSE offered a different lever but i would have to ship post back to them to get it . what i have seen of the other lever i dont like to bulky , looks like a mini brake lever) I WOULD NOT BUY THIS SEAT POST AGAIN , I WILL SELL THE RASSE BLACK MAMBA I HAVE AND BUY A DIFFERENT BRAND ADJSUTABLE SEAT POST

Expand full review >>

Favorite Trail:   BARTS RANCH

Duration Product Used:   3 months

Price Paid:    $280.00

Similar Products Used:   3 maverick speed balls , 2 gravity droppers

Bike Setup:   nomad hd

Overall Rating:5
Value Rating:4
Submitted by ohmoxide a Downhiller from Hood River, OR

Date Reviewed: October 21, 2010

Strengths:    9 inches, enough said.
Will adjust by the inch from 1 to 9 inches.
Quick response.
Easy Install.

Weaknesses:    The tiniest bit of wiggle.
It is expensive.

Bottom Line:   
This thing rocks. I push the lever and you better be standing because your seat is flying up with force. I love that I can have it all the way down for FR then when I plow back up the mountain I can toss up 9 inches on the fly.

If you have not tried and adjustable seat post, you need to.

If you are tall, you should try this one, the 4 and 5 inch models available from other companies just did not cut it.


Expand full review >>

Favorite Trail:   Post Canyon

Duration Product Used:   Less than 1 month

Price Paid:    $350.00

Purchased At:   Discovery Bikes

Similar Products Used:   none

Bike Setup:   Free Ride

Overall Rating:5
Value Rating:5
Submitted by BoulderMTBR a Weekend Warrior from Boulder, CO

Date Reviewed: September 26, 2010

Strengths:    Full range for long legged riders.

Weaknesses:    Expensive, but what bike components are not.

Bottom Line:   
Highly recommoneded, specifically for taller riders.
I am 6'5" and none of the other droppers extend high enough for me to get full leg extension on long, fire road type climbs. For the downhill I like that I can drop the seat all the way, not just 4 or 5 inches.
Simple spring mechanics. No air, no oil, just a simple spring and you put a small amount of lube on the post.
No problems at all about the post sticking.
Make sure your seat tube has enough length for the 9" post to drop into.
The KSi900 I bought never worked. The bike shop took it apart and put it back together twice, but the the post was frozen - would not move an inch.
Will never ride without an adjustable seatpost again.

Expand full review >>

Favorite Trail:   The one I'm looking at

Duration Product Used:   3 months

Price Paid:    $349.00

Purchased At:   rasebike.com

Similar Products Used:   Joplin, KSi900

Bike Setup:   Yeti ASR 7, The One Brakes, XO Twisters

Overall Rating:5
Value Rating:4
Submitted by edwinharbor a Weekend Warrior from Pasadena, CA

Date Reviewed: August 16, 2010

Strengths:    Well made...locks securely...won't slip!

Weaknesses:    Jiggles a bit from side to side.

Bottom Line:   
I did a video review on YouTube here:


RIDING WITH AN ADJUSTABLE SEAT POST is tantamount to using clipless pedals on a mountain bike. Not what you thought it would be, BETTER! Like the fact that clipless pedals not only help the climb easier and better, but also makes the ride safer by keeping ones feet on the pedals over the bumping and jarring of a technical trail ride. Something you did not expect to be a benefit? Just try riding now without your clipless pedals on a nice rough trail and you will see what I am talking about.

Same thing with using an adjustable seat post, yes the rider is now able to climb easier and better since the seat can be raised (on-the-fly) to the optimum leg extension for the most power to the pedal. Yet there is more, much more gained from an adjustable seat post. I am guessing that there are going to be two types of rider opinions when it comes to using an adjustable seat post: Those that are now able to run their seats higher on the climb and those that are able to run it lower on the down. Since, without the adjustability one has to choose where they want to run the fixed seat post; set on the lower side for the technical down or on the higher side for the climb. Either way, efficiency or safety are compromised.

That is where the cut and dry benefits of an adjustable seat post stops. I found myself raising the seat post as I rode down fast loose single track. Why raise it? Because having the seat up against my thighs actually made the descent faster and safer. Seems backwards, but my backside was able to both stabilize the tail of the bike and the weight placed on the seat helped with braking whenever I needed to scrub speed. Normally on those same areas I would have been standing on the pedals with the tail whipping around a bit, and a light occasional skid from the rear tire. With the seat post higher, neither of those things happened.

Additionally, what I assumed would help a small amount was actually a huge boost. That was the ability to pop the seat height up just before climbing short (15 -- 20 foot) steep and technical inclines. I probably did not go up that much faster, but at the top of those short climbs I had exerted half the energy that I would have with my "happy medium" fixed seat post setting. Further, rather than standing to get the power to the pedal, I was able to keep my ass on the saddle, giving my rear tire much more traction while sprinting up the loose rocky path.

For over a year I have chosen not to use an adjustable seat post. Not because I assumed they were not worth the money or effort, but rather because I did not want the additional failure probability. I say "probability" because everyone I know, that has an adjustable seat post, has had problems with slippage and loss of pressure. A mechanical seat post (like the RASE) pretty much can't have that problem. Since the RASE is not a compressed air system -- rather it uses a spring and a metal pin in hole locking system -- the chance of failure is almost zero. I like those odds.

Whenever I selected a height (20 positions to choose from across 9 inches of travel) I never felt like the seat would not stay, and it did not slip once. However, an annoyance I found in the RASE, because it uses a pin in a hole system, the hole needs to be a tad larger than the pin to ensure a quick lock. Thus, a slight (1/8 of an inch) left to right seat jiggle does occur. It is noticeable mostly when you move the bike around, holding onto the seat, and are not sitting on it. Occasionally I could feel it while riding, probably after a couple of rides I will not even notice it.

In the end, I will never ride a mountain bike without an adjustable seat post again. And, based on the design, quality and workmanship of the RASE that seat post will always be a RASE adjustable seat post.

Expand full review >>

Favorite Trail:   WinterCreek

Duration Product Used:   Less than 1 month

Overall Rating:4
Value Rating:4
Submitted by scottg a Cross Country Rider from Fernie, BC, Canada

Date Reviewed: September 24, 2009

Strengths:    9" of adjustment - 3" was not enough. Easy to set maximum height. Less side to side play than Joplin. Seems like it will be easy to maintain myself - should be more reliable than Joplin.

Weaknesses:    Binds a little when lowering if my weight is towards the back of the seat.
Seat clamp not great. I wish it were a straight seat clamp instead of the setback one.

Bottom Line:   
I don't think this is perfect yet, but it seems to be the best adjustable seatpost so far. I started with the Maverick Speedball, and once I went to an adjustable seatpost I could never go back to a static one.

Expand full review >>

Favorite Trail:   Alpine Trail

Duration Product Used:   Less than 1 month

Price Paid:    $290.00

Similar Products Used:   Joplin, Maverick Speedball.

Bike Setup:   Heckler with lotsa cool stuff.

Overall Rating:3
Value Rating:3
Submitted by dorse a Weekend Warrior from Vancouver

Date Reviewed: September 22, 2009

Strengths:    great idea

Weaknesses:    seat clamp

Bottom Line:   
When are manufactures going to put a decent seat clamp on these wonder full seat posts. PS The gravity dropper while not perfect at least does what it claims

Expand full review >>

Duration Product Used:   Less than 1 month

Price Paid:    $222.00

Similar Products Used:   joplin, gravity dropper, KSi900R,

Bike Setup:   nomad

Reviews 1 - 15 (19 Reviews Total) | Next 15

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RASE Black Mamba Rapid Adjust Seatpost - $302 - Group Buy

The price for this group buy is $302 + shipping. I was told that shipping is cheap, $6-$7. [B]Manufactures site (manual, testimonials, support):[/B] [url]http://www.rasebike.com/rapid.htm[/url] [B]MTBR Review:[/B] [url]http://www.mtbr.com/cat/controls/seatpost/rase/black-mamba-rapid-adjust/P ... Read More »

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