SRAM Grip Shift Front Derailleur Question



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Swamprun

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Just got an Actionbent Jetstream on Friday. I've spent a few hours trying to get this beast
together. The front derailleur is by Shimano, the grip-shift is by SRAM.

I can not get the front derailleur to shift properly. Going from position 1 to 2, the cable gets
reeled in way too much. It shifts hard all the way from the small to the large chainring, completely
bypassing the middle. It is stopping at position 2 with the cable good and tight, and the derailler
hard against the stop.

I compared the amount of cable movement to a working Shimano triple front with Ultegra shifters, and
the SRAM is pulling way more cable per click.

Is it possible I have some version of SRAM which is incompatible with the Shimano triple front
derailleur ?

Regards, Greg
 
"swamprun" skrev

> Is it possible I have some version of SRAM which is incompatible with the Shimano triple front
> derailleur ?

If the shifter has a number... 5.0 etc its incompatible. If it has a name like Centera, Attack etc.
it should be Shimano compatible.

Mikael
 
On the shifter it says X-7. Looks like a verified problem.

>
> If the shifter has a number... 5.0 etc its incompatible. If it has a name like Centera, Attack
> etc. it should be Shimano compatible.
>
> Mikael
 
I am not sre that is correct. granted any sram with a number on it is only compatible with a sram
REAR derailleur, but it should work with that shimano 105 front derailleur. hang on, somebody like
"lowracer" will clear it up, or post it to the technical section on BROL, but I do think it should
work, mine is.

swamprun wrote:
> On the shifter it says X-7. Looks like a verified problem.
>
>
>>If the shifter has a number... 5.0 etc its incompatible. If it has a name like Centera, Attack
>>etc. it should be Shimano compatible.
>>
>>Mikael
 
"bentbiker" <[email protected]> skrev i en meddelelse
news:[email protected]...
> I am not sre that is correct. granted any sram with a number on it is only compatible with a sram
> REAR derailleur, but it should work with that shimano 105 front derailleur. hang on, somebody like
> "lowracer" will clear it up, or post it to the technical section on BROL, but I do think it should
> work, mine is.

Right. I was thinking rear der. Dunno about front then.

M.
 
I took off the bike, and now I can easily measure the cable travel.
1/2 inch between numbers 1 and 2, and 3/8 inch between 2 and 3. That's a total of 7/8 cable take up
between the small and large chainring. That seems like too much.

Will try to post the same to the BROL tech board.

On Sat, 25 Oct 2003 17:54:06 -0400, bentbiker wrote:

> I am not sre that is correct. granted any sram with a number on it is only compatible with a sram
> REAR derailleur, but it should work with that shimano 105 front derailleur. hang on, somebody like
> "lowracer" will clear it up, or post it to the technical section on BROL, but I do think it should
> work, mine is.
 
bentbiker must be edykated coz e writed:

> I am not sre that is correct. granted any sram with a number on it is only compatible with a sram
> REAR derailleur, but it should work with that shimano 105 front derailleur. hang on, somebody like
> "lowracer" will clear it up, or post it to the technical section on BROL, but I do think it should
> work, mine is.
>
> swamprun wrote:
>> On the shifter it says X-7. Looks like a verified problem.
>>
>>
>>> If the shifter has a number... 5.0 etc its incompatible. If it has a name like Centera, Attack
>>> etc. it should be Shimano compatible.
>>>
>>> Mikael
>>
>>
>
Sram front shifters are compatible with Shimano and Campag front mechs. Afterall Sram do not make
front mechs so there is no point in them being Sram specific.

--
Ian

http://www.catrike.co.uk
 
Originally posted by Mikael Seierup
If the shifter has a number... 5.0 etc its incompatible. If it has a name like Centera, Attack etc. it should be Shimano compatible.898/B]


Um. . .no.

That is for the rear derailleur. Front derailleurs will work with virtually any SRAM version. Take a look at the specs on a lot of bikes for this.
 
> Um. . .no.
>
> That is for the rear derailleur. Front derailleurs will work with virtually any SRAM version. Take
> a look at the specs on a lot of bikes for this.

That appears to be true. When SRAM says "Shimano Compatible", they are referring to the rear
derailleur only. Which means my X-7 should work, but hell if I can figure out how.
 
it might have something to do, with that low end crank set on the Jet stream, have another one you
can throw on to try it?

swamprun wrote:

>>Um. . .no.
>>
>>That is for the rear derailleur. Front derailleurs will work with virtually any SRAM version. Take
>>a look at the specs on a lot of bikes for this.
>
>
> That appears to be true. When SRAM says "Shimano Compatible", they are referring to the rear
> derailleur only. Which means my X-7 should work, but hell if I can figure out how.
 
I don't think the crankset is the main problem. I spent about 1.5 hours working on the cursed thing
today. I found I could get some degree of proper functioning by leaving quite a bit of slack in the
cable in position 1 (small chainring). It shifts quite well to the middle chain ring now without
overshooting. The shift to the large chainring requires a LOT of force to get to the third click. I
pushed the high limit screw to the absolute max of pushing the chain off the outside of the big
chainring to reduce the cable tension as much as possible.

Another thing I learned today is that SRAM makes 2 versions of the front twist shifter. There is an
"indexed" version, which is what I have, and a "micro adjust" version which apparently has a whole
bunch of smaller clicks. I looked at several online bike stores selling SRAM stuff, and only one of
them shows the selection for the micro-adjust option. This may be the way to go to get decent
function out of this contraption.

On Mon, 27 Oct 2003 19:47:30 -0500, bentbiker wrote:

> it might have something to do, with that low end crank set on the Jet stream, have another one you
> can throw on to try it?
 
swamprun wrote:
> ... Another thing I learned today is that SRAM makes 2 versions of the front twist shifter. There
> is an "indexed" version, which is what I have, and a "micro adjust" version which apparently has a
> whole bunch of smaller clicks. I looked at several online bike stores selling SRAM stuff, and only
> one of them shows the selection for the micro-adjust option. This may be the way to go to get
> decent function out of this contraption.

Having used both three position (SRAM 5.0), six position (SRAM 7.0) and eight position (SRAM Plasma)
GripShifters, I prefer to have the maximum number of detents, as it allow trimming of the front
derailleur to avoid chain rub.

On an USS HPV, I prefer Shimano Ultegra (8-speed) and Dura-Ace (9-speed) bar end shifters.

Tom Sherman - Near the confluence of the Mississippi and Rock Rivers RANS "Wavewind" and Rocket,
Earth Cycles Sunset and Dragonflyer
 
Something else to check. Make sure that the derailleur cable is attached to the derailleur at the
right place and angle. If you completely remove the pinch bolt which holds the cable to the
derailleur, you should notice a groove under the screw which the cable should be located in when the
screw is tightened. Also my Shimano derailleur has a little lip or raised place right at the pinch
bolt, on the derailleur itself. At this point, where the cable exits the pinch bolt, the cable needs
to bend up and over the lip and then down to the cable housing stop on the frame. This lip positions
the cable out near the end of the lever arm which operates the derailleur. This establishes the
correct distance from the pivot of the lever arm that the cable needs to be at. If the cable
attaches to the pinch bolt too close to the pivot point, then the derailleur cage will move too far
between the clicks and will also require more torque at the shifter to get the cage to move. If the
cable is attached further from the pivot then the derailleur cage will move less per click and will
require less torque at the shifter. My Shimano rapid-fire shifters pull 3/4 of an inch of cable
across their full range. That only about an 1/8 of an inch less than yours. So it sounds like your
shifters are pretty close to what they should be. It is ok for the cable to be a little slack while
in position 1. Make sure that your cable is attached correctly at the derailleur. Hope this helps
and isn't too confusing. If you would like me to clarify, please don't hesitate to ask.

Greg
 
On Tue, 28 Oct 2003 18:08:30 -0500 (EST), [email protected] (Greg Eicher) wrote:

> Something else to check. Make sure that the derailleur cable is attached to the derailleur at
> the right place and angle. If you completely remove the pinch bolt which holds the cable to
> the derailleur, you should notice a groove under the screw which the cable should be located
> in when the screw is tightened. Also my Shimano derailleur has a little lip or raised place
> right at the pinch bolt, on the derailleur itself. At this point, where the cable exits the
> pinch bolt, the cable needs to bend up and over the lip and then down to the cable housing
> stop on the frame. ....

Good point. Here's a photo: http://www.hostelshoppe.com/tech_frontderail.php

Ken Kobayashi [email protected] http://solarwww.mtk.nao.ac.jp/kobayashi/personal/
 
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