Conference noted::bicycle

    
    	Looks hot.
    		Seems to be solid design. My friend has the stem and loves
    it.
    	Roger

    Suspended bikes seem to be getting popular these days. You might want
    to see what the other manufacturers produce. I know C-dale will have
    one this year. Probably others too.
    
    John

    Several manufacturers (Cannondale, Fisher, etc.) will be offering MTB's
    with suspension for '91. I believe that Gamache's in Fitchburg already
    has one or more of the C-dale's in stock.
    If I were going to buy one, I'd check 'em all out before I put my money
    down.
    
    Pete
    

    Don't go for some of that mamby-pamby marketing hype they call
    suspended systems!  It's just more weight to carry around.  What
    are you, a wimp - can't take the New England bumps!  Go for the
    Wicked!  It was made for this area and it shows it.  I wouldn't
    trade mine for anything...
    
    mark

    .4  Amen!!!
    
    Dick
    

    	Generally, I haven't seen much literature lately. But in recent
    	years, I've seen articles on various designs for HPV suspension
    	systems. Another one I've seen is from Alex Moulton, at least I
    	think that's how you spell his name.  This guy's been designing
    	some radical looking HPV's in general, let alone the suspension
    	"angle" on 'em.
    
    	One of the biggest arguments concerning suspension systems:
    
    	Energy loss.
    
    	It is virtually impossible to achieve a solid  drive-line on an
    	HPV.  Therefore, there's going to be some amount of energy lost
    	in the transmission. Flex, vibration, friction, all play a part
    	in determining what percentage of your  energy expenditure will
    	be lost, or spent in vain.
    
    	Hence the argument, suspensions only absorb shock and vibration,
    	they do not transmit them. *Any* energy generated, specifically
    	for the purpose of  locomotion,  can only be  diminished by the 
    	presence of a suspension system.
    
    	That is just what I've heard, I'm no engineer. The situation is
    	far more complex than my meager intelligence can understand.
    
    	I know bumps are a real problem, but I feel a little better now,
    	knowing that "all" of my pedal strokes are pushing me forward.
    
    	Of course, as soon as I see the new Off-road product, all logic
    	will be cast to the wayside as I drool on the latest technology.
    
    	I'll shut up, & stop flappin' my fingers on this here keyboard.
    
    						Regards, Face

    
    	I'm looking at Mountain Bike Action /November right now
    and these bikes are in there.
    	Also there is considerable discussion and product review on
    another similar design and that is aluminum frame or triangle with
    steel stays. Looks like the best of both worlds.
    	Something that they say in the mag, in the article on the slingshot
    which is radical,is that the suspension frames turn the bump energy
    into power?
    
    	Roger

    I rode a bunch of bikes, including the Bridgestone MB-0 (zip),
    Specialized Stumpjumper, and Wicked Fat Chance before buying 
    this thing last night.  I have to admit that the Fat Chance 
    was a beautiful bike....unfortunately, at $1600+, it was out
    of reach.  (I liked it slightly better in trials situations,
    and slightly less for descents.  It weighed less, too, but not
    MUCH less.)  Nothing else even came close.  
    
    The frame quality on this Serotta-built bike is outstanding.
    Next years' will be made off-shore.  
    
    I got a great deal on the bike.  There's currently a dispute
    between Serotta and Offroad -- Serotta delivered their last
    two production runs two weeks' late;  Offroad refused to take
    them, using the lateness as an excuse, but more probably because
    they've already lined up their new suppliers.  Serotta, stuck
    with this inventory, started dumping the remaining bikes on the 
    market.  Offroad counterattacked, claiming to dealers that they
    had rejected the frames for "quality reasons", and that they'd
    refuse to warrantee them.  Then they dropped their own wholesale
    price on the Pro-Flex because dealers complained about Serotta
    undercutting their price.  
    
    The net result was that I was able to go into the dealer where
    I originally rode the bike, take it away for $500 under list,
    and the dealer got a credit from Offroad for the difference.
    
    If any of you is interested in an 18" Pro-Flex, you can get
    one for $895 by calling Serotta Sports at 1-518--587-9085.
    This is for a Deore XT-equiped bike with a True Temper frame,
    by one of the premier builders in the country.  Not bad!
    
    MATT

    I forgot to mention that Offroad backed off on its quality story
    when challenged.  (It was analogus to Roger Smith saying that
    Lexus sedans were badly built when they came out.)
    
    MATT

    I've read a few articles as well.  It seems that the jury is still out. 
    The suspended bikes work well but many people still think that where
    there is active suspension there is power loss.  I would like to ask
    Matt and any other people who log some miles on these bikes to reply
    with more info.  I am looking at buying a new bike and can appreciate
    anything that can take the jarring out of the rock/root strewn
    downhill singletrack in Southern N.H.
             

    A well-designed suspension dampens up-and-down motion, not forward 
    and back.  If the Pro-Flex sucks up any power, it's not perceptible.
    Alternative ways to reduce shock, like fatter tires/lower pressure,
    have a much greater impact:  at least that was my impression 
    yesterday when I tried John Crane's Trek with the Ground Control Extreme
    2.5s.  (Of course, the GC 2.5's have other other benefits in extreme
    situations, like soft sand -- John could just float over it, while
    Roger and I had to plow through.)
    
    The Pro-Flex's forte' is flailing down root-crossed paths on the
    flats/downhills.  I don't have a lot of experience with MTB's, but
    it seems pretty competent at other things, too.  (As a rider, on 
    the other hand, I have a lot of work to do!)
    
    Matt ("Endo") Johnson

    
    	As viewed from behind most of the time I would say the Off Road
    didn't soak up too much power. It did obviously soak up mucho hammering
    and although Endo 8*) tried very hard to break it held up to a good
    amount of abuse.
    	I think it should be taken to the next level with a set of 2.5's.
    Hot looking bike too.
    
    	Roger

    I'd like to revisit this note now that ATB's with suspensions have
    become more popular and hopefully get some more data points on
    suspensions.  Bicycling had a writeup on how the two most popular
    types work; basically they aren't "active" until a certain
    threshhold is reached, so the earlier claim of always robbing energy
    seems bogus.  The weight issue is certainly valid though, but it's
    interesting to see the high-end aluminum and titanium ATBs coming
    with suspensions these days.  Obviously, with the majority of ATB's
    ridden on roads (where suspensions would be of minimal value), they're
    not for everybody.
    
    Anyhow, I'd like to hear from those that have ridden suspended
    (front or both) ATBs on trails and get your opinion: fad/not worth
    the weight, or no-going-back/worth their weight in gold.  Prethanks. 
    -kb
    
     

I recently installed a Trek DS2 fork on a Diamond Back Apex. I've only gone
for two test rides so far, both over a variety of trail conditions ranging
from dirt roads to rutted trails.  Ground conditions included some snow, ice,
water, mud, sand, roots, grass, rocks, etc.  The terrain was hilly, but nothing
exceedingly steep.  

Some observations....

- Had very good control on rocky/rutted climbs and descents.
- No numb hands after the rides
- Steering about the same, maybe some oversteering (?)

Getting the air pressure right is a hit and miss process.  I think mine are 
at around 30-35 psi.  I have not noticed any bouncing on climbs, and they 
appear to be operating within their full range of travel (determined by 
measuring the clean part on the stanchions). 

Aside from the price, I'm glad I made the change.  

Rich

How much was the fork?

$250

I installed a Marzocchi fork on my Specialized Stump Jumper.

I've been using it for about 4 months now. It's forte is improved handling on
rough, technical trails and downhill.

The weight takes a little getting used to, but I really like the ride.

As pointed out previously, setting the air pressure was by trial and error. I 
run my pressure about 20% higher than the value in the directions given for my 
weight and riding surface. But, I ride over very rocky trails with lots of 
oportunity to bottom the suspension out at lower pressures.

It takes a little getting used to on rough downhill runs. The bike rotates 
forward more after a bump and front wheel landing. However, it absorbs the 
momentum of the bumps and I can maintain a much higher speed.

It's main advantage on single track is the vibration absorbtion/dampening.
My hands and arms don't get tired as easily.

-Eric L.

    
    I just bought an Offroad Proflex.  As soon as this *&%! snow gets down
    to a reasonable level, I'll be able to ride.  I'll let you know what
    it's like.
    
    Steve

    There's a fairly long article in the April issue of "Mountain Bike
    Action" on suspensions.  They discuss different models as well as
    extensive test ride comparisons.  This is the first time I've read this
    magazine.  How accurate are they?
    
    Ken
    

    
    
    Its been almost a year since any additions to this note. My 1987
    Stumpjumper developed a crack the headset/downtube weld about a month 
    ago. Two weeks ago, I took it to a Specialized dealer and they are 
    replacing the frame (free of charge 8^)).  I rode the Ol' Stumpjumper 
    really hard at times, and had considered a suspension fork, but I just 
    couldn't see putting a $300 fork on a 5-6 year old bike. Now that I will 
    have an essentially brand new bike,  I'm reconsidering the suspension 
    fork decision. So:
    
    1. Is anybody still riding a suspension fork? What brand/model?
    2. What form of suspension does it employ (ie. Spring/Air/Oil/Elastic)?
    3. Was it worth the $$$ to you?
    4. If you went MTB'ing BEFORE you purchased fork, please comment 
       on any before/after comparisons you might have made. 
    5. What type of maintenance do you perform? How often? Is this
       different from what your owners manual suggests?
    6. How many miles or hours have you put on your fork?
         
    
    Unfortunately, magazine reviews never say anything really bad about
    suspension fork brands, they never make recommendations, so the 
    reviews are all pretty much fluff and hype.
    
    Any information/impressions are appreciated!
       
    doug  

    
    
    Well, it's been another 10 months since my last reply, and I finally
    splurged for a Specialized Future Shock. Me and my bike really took
    a beating this year in training for and competing in races. I got some
    top 15 placings in First Timers and Beginner's class racing. My best
    placing was last week at the Ga MTB Championships. I started out about
    20th, and picked my way to the front. I led for more the half the race.
    Eventually one guy slowly caught and passed me. I see-sawed with
    another guy for 2nd/3rd until the last half mile.... I blew a tire!
    I ran the bike in the last half mile for 12th place (out of 60-80). 
    From my racing observations, the Rock Shox Mag21 was the
    #1 suspension preference, followed by the Specialized Future Shock
    (Specialized licenses the Rock Shox technology), followed by the
    Manitou 2.  Anyway, Nashbar has the Future Shock on clearance
    for $239 for a 1" steerer. It came today and I can't wait to put it
    on the bike.  
    
    
    doug
    

    
    
    
    Here's another tidbit from the internet on changing shock oil:
    
Article 12418 of rec.bicycles.tech:
Newsgroups: rec.bicycles.tech
Path: netnews.alf.dec.com!pa.dec.com!decwrl!spool.mu.edu!howland.reston.ans.net!vixen.cso.uiuc.edu!moe.ksu.ksu.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!mbushore
From: [email protected] (Matt Bushore)
Subject: Re: More Suspension Questions...
Originator: mbushore@l_cae12
Sender: [email protected] (News)
Message-ID: <[email protected]>
Date: Wed, 27 Oct 93 13:33:02 GMT+5:00
References: <[email protected]> <[email protected]>
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In article <[email protected]>, [email protected] (Mark Obsniuk) writes:

|>  Well you need some Automatic Transmission fluid. A 19mm wrench, air pump, 4mm
|> allen key and a philips screw driver. 
|> 
|>  Well you let the air out of the fork.
|>  Take the 4mm allen key and release the fork legs from the crown.
|>  Take them 19mm wrench and remove the top piece.
|>  Drain the fork leg into a container. Pump about 10 times to remove all oil.
|>  Put in desired amount of oil(some like more then others). Pump again about
|>     10 times to remove air inside legs.
|>  Put top piece back on and then pump legs to over 60lbs. Let rest for over an
|>     hour. Then let air out till it is at the value that you want.
|>  Reattach legs to brace and your off.
|> 
|>  Other then the hour or so wait it really is about a 10 minute job. And very 
|> easy.
|> 
|> Mark
|>  


I am sure that no one really cares, but in case someone is grumbling...

You can use a compressor to put about 100-120 psi into the shocks.
The oil will become saturated with air in about 10 minutes or less.
The stock oil height is 35 mm for Mag 20's and 40 mm for 21's.
This is with the tubes compressed.

Also, the ATF is a bit heavy for most people.  Using 5wt (riders under 160)
will likely give you a better ride.

-- 
Matt Bushore


-- 
Matt Bushore




    
                                                                 

    
    
    
      Anyone got a Pro-Flex bike, the sytle with rear suspension and a
    front Vector suspension. A bike store has some '93 models for sale
    for cheap.
    
     I'm trying to resist.
    
     Is there a verdict (yet) about fully suspended bikes? What does any-
     one think of the Pro-Flex?
    
    /regards
     Wayne V
    
    

    I puchased a Pro-Flex 854 two days ago.  My previous bike was a
    Stumpjumper with a Future Shock.  On the plus side, compared to the FS,
    the Pro-flex fork legs do not move independently, which provides much
    more precise steering, especially which hitting a bump going aroung a
    downhill corner.  Because it's elastomer, it responds to little bumps
    and washboard better.  This also helps if you want to hop the front 
    over an obstacle.  However, bigger longer bumps cause a faster
    rebound than I'm used to, but most of that can be soaked up by my arms. 
    There is also a little more pogo-ing when sprinting out of the saddle. 
    The owners manual says the dampening will improve after some more break-in
    time.  So, it is different that the typical air/oil shock, but I think
    the positives outweigh the slight negatives.  Pro-flex does offer 
    a dual elastomer upgrade to the front (similar to the rear),
    which supposedly  helps  out in the sprints.
    
    The rear suspension works great.  The bike handles rocky trails very
    capably and has a much more comfortable ride.  I do not notice the rear
    suspension when the going is smooth, except a little when standing. It
    gives me more confidence descending, and really digs in on the hard
    climbs.   
    
    I ride in the Phoenis area, where there are lots of rocks.  The bike is
    getting to be pretty popular here.     Hope this helps.
    
    Jim