Conference noted::bicycle

	I don't think click shift is going to solve your problem.  If 
	your bike is changing gears 'cause the derailleur's actually
	moving, you need to tighten up the shifter, etc.  If that's
	not it, the chain could be jumping around due to worn chain
	and freewheel.  Since you imply that it only does it when
	you're climbing, this is likely.  It will still do it with
	click shift unless you fix the real problem.

	chris

.1 only answered part of the question, but did not address the 2nd paragraph:

>    I am broadening the range on the freewheel from 14-24 to 13-28.
>    A new freewheel needs a new chain. And Click obviously requires
>    new shifters. Can I salvage the old derailleur? Its Suntour ARX
>    6-speed. Do I need matched (Suntour) components, or can I mix in
>    a Sedisport chain or a Shimano freewheel?

	(I point this out because I also want to broaden my freewheel range
	 and want to know whether I need to replace my stuff with Suntour
	 components!)

I'm uncertain about what you mean by "click shift".

Are you talking indexed shifting?  If that is the case, then you generally need
to have a matched freewheel/derailleur/shifters, because everything has to move
certain amounts.

There are (were?) also shifters that clicked when you moved them, but were still
basically a friction setup.  I doubt that this is what you would be getting as
this was before indexed shifting and was put in there to provide some feedback.

Rich

    (in .3) I think that he meant indexed shifting.

    What we really need is a table for each variety of shift lever
    that says "This shifter moves N.NN millimeters per click"

    Also, we need a table for each rear deraileur that says
    "This gear changer has chain-displacement to cable-movement
    ratio of N.N"

    Finally, get a table for each kind of freewheel or cassette hub
    that says "These cogs are N.NN millimeters apart."


    If you multiply the first number by the second number and
    get the third number, then the system will work, right?

    Or is it more complicated than that?

    One reason gears 'jump' was already mentioned ... worn chain/cogs.
    
    Another reason is frame flex; I believe the flex stretches the cable
    very slightly, but enough for the chain to jump under load.
    My brother has a problem with his Vitus jumping gears on uphills.
    The frame flexes so much, and his cable is so long (bar end shifter on
    the end of a Sark bar), that the cable stretches when the frame flexes.
    His solution is to consider a new frame, since he won't give up the
    bar-end shifter. I'm bummer he's considering a new frame; the only way
    I'd beat him up hills was when his chain jumped a gear!
    
    Mark
    

    re .-1
    	I recall from an article in Bicycling Magazine some time back that
    the cog spacing (at least on Shimano) isn't uniform.  Guess it's _not_
    quite that simple.

    1. You need to find your present "auto-shifting" problem.
    Could be frame/b.b flex, worn parts or adjustments.
    
    2. You can do a "controlled" upgrade, but stay with one brand.
    Some chains will work with multiple setups.
    
    3. If staying Suntour, find what chains work the best with suntour.
    Install new freewheel and new chain.  See if Shifting OK.
    If not; buy Suntour rear der. for 13/28 rear and present front
    gearing index compatible.
    
    4. If wanted, swap shifter and cables (Suntour).
    
    So you could go this way, if you want. But be sure that all
    New part are compatible.  There are some magazine articles that
    desribe this, (time at local library) or call performance, nashbar
    or any GOOD bike shop.

    Thanks for the input so far... here's where I am:
    
    Goodale's suggested gear jumping may be worn shifter bushing. I am
    investigating. They suggested matched upgrade components: indexed shifter/
    derailleur/freewheel/chain.
    
    Bike Nashbar suggested I could salvage the derailleur, and also mix in
    the Sedisport chain on the Suntour freewheel. (They don't carry the 
    Suntour chain - Performance does.)
    
    My current plan is to buy Suntour shifters and freewheel hoping the
    Accushift gruppo is downward compatible with the ARX 6-speed
    derailleur, as noted earlier. I'll risk it with the sedisport chain.
    
    Re - .2: Increasing gear range with your existing derailleur is known.
    Pick up Nashbar or Performance and check your (or similar) derailleur
    gear teeth capacity and maximum gear teeth. This determines your
    freewheel range.
    
    Thanks, all.		SR