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Changing gripshift 7-speed to rapid-fire?



 
 
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  #1  
Old June 23rd 05, 06:39 AM
rs
external usenet poster
 
Posts: n/a
Default Changing gripshift 7-speed to rapid-fire?

I'm pretty new to cycling after a 25 year break so this question may be naive.

I recently purchsed a bike (used Univega Via Montega) and it has Front
derailleurer: Shimano Altus 3-speed & rear derailleur: Shimano RSX 7 speed
with the shifters being Gripshift MRX on my flat handle bar. I like those
rapid shifters I see on some bikes, a friend has a bike that I think has
shifters that say BS on them and you use your thumb to upshift and index
finger to release to shift down and they seem to work well.

Can my bike be converted to those type of shifters and what would be the
proper parts to buy? Would it be STX/Alivio SL-MC40 or Shimano Rapidfire 7
seven speed shifters, model SL-MC40 which I'm guessing are the same thing?

Also is it even worth it? how much should all this cost?

thanks to all!!


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  #2  
Old June 23rd 05, 07:22 AM
Werehatrack
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Posts: n/a
Default Changing gripshift 7-speed to rapid-fire?

On Thu, 23 Jun 2005 00:39:35 -0500, (rs)
wrote:

I'm pretty new to cycling after a 25 year break so this question may be naive.


Only the question not asked is truly naive.

I recently purchsed a bike (used Univega Via Montega) and it has Front
derailleurer: Shimano Altus 3-speed & rear derailleur: Shimano RSX 7 speed
with the shifters being Gripshift MRX on my flat handle bar. I like those
rapid shifters I see on some bikes, a friend has a bike that I think has
shifters that say BS on them and you use your thumb to upshift and index
finger to release to shift down and they seem to work well.


Actually, in most cases, one side shifts up with the index finger and
the other side shifts up with the thumb, but I agree with your overall
evaluation; I personally prefer this type of setup as well.

Can my bike be converted to those type of shifters


Certainly.

and what would be the
proper parts to buy? Would it be STX/Alivio SL-MC40 or Shimano Rapidfire 7
seven speed shifters, model SL-MC40 which I'm guessing are the same thing?


Any of the SIS-compatible shifters should work, which basically means
just about any 7-rear/3-front indexed Shimano bits for a mountain bike
should do the job. The Alivios have worked well for me, as have the
Deore and Altus. The Rapidfire feature (which permits the
thumb-operated lever to traverse several clicks with one long push
when shifting the rear) is present on a number of the Shimano setups.
The only potential hassle is that many of the shifters have integral
brake levers, and the majority of the setups are likely to be built
for V-brakes; if your Univega is old enough that it has cantilever
brakes, you may have to convert to V-brakes when you upgrade the
shifters.

Also is it even worth it?


Only you can answer that question. I'd have no qualms about doing it
if the bike fits and rides well otherwise.

how much should all this cost?


With careful shopping, if you have V-brakes on the bike now, it might
be done for as little as $35 including new cable housings. Perhaps
less if you can scrounge used parts. If you have canti brakes, the
cost goes up.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.
  #3  
Old June 23rd 05, 08:30 AM
Ron Hardin
external usenet poster
 
Posts: n/a
Default Changing gripshift 7-speed to rapid-fire?

My experience is that the MRX shifters will break (the clicker thing
breaks off) pretty quickly, giving you an excellent time to do the
conversion. Or you can run them as friction shifters by wedging
a yoghurt container strip of plastic under the knob to raise
the friction a little, and continue to use a broken one.

Occasionally a MRX shifter goes a year for me (8,000 miles) but
usually they last a month or so. Whether it is some horrible run
of quality control and not general, I don't know. I've gotten
them from a number of different sources and they all break.
--
Ron Hardin


On the internet, nobody knows you're a jerk.
  #4  
Old June 23rd 05, 02:43 PM
Werehatrack
external usenet poster
 
Posts: n/a
Default Changing gripshift 7-speed to rapid-fire?

On Thu, 23 Jun 2005 07:30:09 GMT, Ron Hardin
wrote:

My experience is that the MRX shifters will break (the clicker thing
breaks off) pretty quickly, giving you an excellent time to do the
conversion. [snip]


Same results here. I loathe gripshifts in general, but those seem not
only annoying but downright fragile. SRAM makes better ones in my
opinion, but I still greatly prefer levers of some sort.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.
  #5  
Old June 24th 05, 12:59 AM
rs
external usenet poster
 
Posts: n/a
Default Changing gripshift 7-speed to rapid-fire?

Thanks to all for the info. Bike does have V-brakes (they work well) and as
someone seemed to indicate, I find
the grip shifters plasticky & cheesy. Sounds like the Shimano Alivio I
previously mentioned should work and
I'll probably go for them.

However, a friend's bike has these rapid shifters where the shift to larger
gear on either front or back
requires preassure and uses the thumb. The shift down releasing tension and
to a smaller gear releases with
the index finger and the whole thing is not integral to the brakes but mounted
right next to them (or course)
but underneath. They don't have any type of window-indicator as to which gear
you're in (which I don't need)
but they do have the logo BS as I recall on them and no other writing. What
brand or type are these?

Rick

In article ,
says...

On Thu, 23 Jun 2005 00:39:35 -0500,
(rs)
wrote:

I'm pretty new to cycling after a 25 year break so this question may be

naive.

Only the question not asked is truly naive.

I recently purchsed a bike (used Univega Via Montega) and it has Front
derailleurer: Shimano Altus 3-speed & rear derailleur: Shimano RSX 7 speed
with the shifters being Gripshift MRX on my flat handle bar. I like those
rapid shifters I see on some bikes, a friend has a bike that I think has
shifters that say BS on them and you use your thumb to upshift and index
finger to release to shift down and they seem to work well.


Actually, in most cases, one side shifts up with the index finger and
the other side shifts up with the thumb, but I agree with your overall
evaluation; I personally prefer this type of setup as well.

Can my bike be converted to those type of shifters


Certainly.

and what would be the
proper parts to buy? Would it be STX/Alivio SL-MC40 or Shimano Rapidfire

7
seven speed shifters, model SL-MC40 which I'm guessing are the same thing?


Any of the SIS-compatible shifters should work, which basically means
just about any 7-rear/3-front indexed Shimano bits for a mountain bike
should do the job. The Alivios have worked well for me, as have the
Deore and Altus. The Rapidfire feature (which permits the
thumb-operated lever to traverse several clicks with one long push
when shifting the rear) is present on a number of the Shimano setups.
The only potential hassle is that many of the shifters have integral
brake levers, and the majority of the setups are likely to be built
for V-brakes; if your Univega is old enough that it has cantilever
brakes, you may have to convert to V-brakes when you upgrade the
shifters.

Also is it even worth it?


Only you can answer that question. I'd have no qualms about doing it
if the bike fits and rides well otherwise.

how much should all this cost?


With careful shopping, if you have V-brakes on the bike now, it might
be done for as little as $35 including new cable housings. Perhaps
less if you can scrounge used parts. If you have canti brakes, the
cost goes up.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.


  #6  
Old June 24th 05, 04:26 AM
rs
external usenet poster
 
Posts: n/a
Default Changing gripshift 7-speed to rapid-fire? WILL the 8-Speed shifter Work?

One shop was out of the 7-speed Alivio SL-MC40 but said the current Shimano
Alivio SL-MC20 for the 8-speed set-up would work fine, just have an extra
click? Is this so, and any advantages or disadvantages?

thanks

Rick


In article ,
says...

Thanks to all for the info. Bike does have V-brakes (they work well) and as
someone seemed to indicate, I find
the grip shifters plasticky & cheesy. Sounds like the Shimano Alivio I
previously mentioned should work and
I'll probably go for them.

However, a friend's bike has these rapid shifters where the shift to larger
gear on either front or back
requires preassure and uses the thumb. The shift down releasing tension and
to a smaller gear releases with
the index finger and the whole thing is not integral to the brakes but

mounted
right next to them (or course)
but underneath. They don't have any type of window-indicator as to which

gear
you're in (which I don't need)
but they do have the logo BS as I recall on them and no other writing. What
brand or type are these?

Rick

In article ,
says...

On Thu, 23 Jun 2005 00:39:35 -0500,
(rs)
wrote:

I'm pretty new to cycling after a 25 year break so this question may be

naive.

Only the question not asked is truly naive.

I recently purchsed a bike (used Univega Via Montega) and it has Front
derailleurer: Shimano Altus 3-speed & rear derailleur: Shimano RSX 7 speed
with the shifters being Gripshift MRX on my flat handle bar. I like those
rapid shifters I see on some bikes, a friend has a bike that I think has
shifters that say BS on them and you use your thumb to upshift and index
finger to release to shift down and they seem to work well.


Actually, in most cases, one side shifts up with the index finger and
the other side shifts up with the thumb, but I agree with your overall
evaluation; I personally prefer this type of setup as well.

Can my bike be converted to those type of shifters


Certainly.

and what would be the
proper parts to buy? Would it be STX/Alivio SL-MC40 or Shimano Rapidfire

7
seven speed shifters, model SL-MC40 which I'm guessing are the same thing?


Any of the SIS-compatible shifters should work, which basically means
just about any 7-rear/3-front indexed Shimano bits for a mountain bike
should do the job. The Alivios have worked well for me, as have the
Deore and Altus. The Rapidfire feature (which permits the
thumb-operated lever to traverse several clicks with one long push
when shifting the rear) is present on a number of the Shimano setups.
The only potential hassle is that many of the shifters have integral
brake levers, and the majority of the setups are likely to be built
for V-brakes; if your Univega is old enough that it has cantilever
brakes, you may have to convert to V-brakes when you upgrade the
shifters.

Also is it even worth it?


Only you can answer that question. I'd have no qualms about doing it
if the bike fits and rides well otherwise.

how much should all this cost?


With careful shopping, if you have V-brakes on the bike now, it might
be done for as little as $35 including new cable housings. Perhaps
less if you can scrounge used parts. If you have canti brakes, the
cost goes up.
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.



  #7  
Old June 24th 05, 07:03 AM
Werehatrack
external usenet poster
 
Posts: n/a
Default Changing gripshift 7-speed to rapid-fire?

On Thu, 23 Jun 2005 18:59:51 -0500, (rs)
wrote:

Thanks to all for the info. Bike does have V-brakes (they work well) and as
someone seemed to indicate, I find
the grip shifters plasticky & cheesy. Sounds like the Shimano Alivio I
previously mentioned should work and
I'll probably go for them.

However, a friend's bike has these rapid shifters where the shift to larger
gear on either front or back
requires preassure and uses the thumb. The shift down releasing tension and
to a smaller gear releases with
the index finger


A shift "down" on the rear would be to a *larger* sprocket. Have you
actually ridden your friend's bike to see how that works?

and the whole thing is not integral to the brakes but mounted
right next to them (or course)
but underneath. They don't have any type of window-indicator as to which gear
you're in (which I don't need)
but they do have the logo BS as I recall on them and no other writing. What
brand or type are these?


Most ders, either front or rear, move to the larger sprockets as the
cable is pulled, and to the smaller ones as the cable is let back out.
Thus the ratio-change effect of the same action at the shifter is
usually the reverse on the left of what it is on the right. To make
them both do "the same thing", the rear der needs to be designed so
that it moves toward the small sprocket as the cable is *pulled*, and
moves toward the larger ones as the cable is *released*. There are
ders which do this, but they aren't as common as the other type. From
what you describe, your friend's bike doesn't have one of the special
rear ders. Yours probably doesn't either. As a result, swapping to
trigger shifters will cause the right and left shifters to do opposite
things as far as the *effect*, even though it's the same thing as far
as the *appearance*. Both will use the same finger to go to a
sprocket of larger diameter, for instance, but the effect of this on
the front is the opposite of the effect on the rear.

Would you take my word for it if I said that the reversed sense of the
action becomes familiar very quickly for most people? It's no big
deal.

BTW, those shifters marked "BS" sound like they're identical to the
set on a Pacific that's in the collection here. They work OK, but the
Alivios are better. Both work the same way when it comes to which
lever does what, though; the thumb lever shifts to larger sprockets
and the index finger lever shifts to smaller ones, unless one of the
special rear ders is used. (Those are called "low normal", or
sometimes "rapid rise" ders. When you used the term "rapid rise"
above, I thought that your friend's bike had one, but your description
of the action fits a normal der, not a low-normal.)
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.
  #9  
Old June 24th 05, 08:34 AM
rs
external usenet poster
 
Posts: n/a
Default Changing gripshift 7-speed to rapid-fire?

Yes, If I wasn't clear previously the thumb shift requireing preassure is
always to the larger gear, front or back. The index releases to the smaller
gear requiring little or no preassure. Referring to high and low is a
misnomer here and confuses the issue.

Rick


In article ,
says...

On Thu, 23 Jun 2005 18:59:51 -0500,
(rs)
wrote:

Thanks to all for the info. Bike does have V-brakes (they work well) and as
someone seemed to indicate, I find
the grip shifters plasticky & cheesy. Sounds like the Shimano Alivio I
previously mentioned should work and
I'll probably go for them.

However, a friend's bike has these rapid shifters where the shift to larger
gear on either front or back
requires preassure and uses the thumb. The shift down releasing tension and
to a smaller gear releases with
the index finger


A shift "down" on the rear would be to a *larger* sprocket. Have you
actually ridden your friend's bike to see how that works?

and the whole thing is not integral to the brakes but mounted
right next to them (or course)
but underneath. They don't have any type of window-indicator as to which

gear
you're in (which I don't need)
but they do have the logo BS as I recall on them and no other writing.

What
brand or type are these?


Most ders, either front or rear, move to the larger sprockets as the
cable is pulled, and to the smaller ones as the cable is let back out.
Thus the ratio-change effect of the same action at the shifter is
usually the reverse on the left of what it is on the right. To make
them both do "the same thing", the rear der needs to be designed so
that it moves toward the small sprocket as the cable is *pulled*, and
moves toward the larger ones as the cable is *released*. There are
ders which do this, but they aren't as common as the other type. From
what you describe, your friend's bike doesn't have one of the special
rear ders. Yours probably doesn't either. As a result, swapping to
trigger shifters will cause the right and left shifters to do opposite
things as far as the *effect*, even though it's the same thing as far
as the *appearance*. Both will use the same finger to go to a
sprocket of larger diameter, for instance, but the effect of this on
the front is the opposite of the effect on the rear.

Would you take my word for it if I said that the reversed sense of the
action becomes familiar very quickly for most people? It's no big
deal.

BTW, those shifters marked "BS" sound like they're identical to the
set on a Pacific that's in the collection here. They work OK, but the
Alivios are better. Both work the same way when it comes to which
lever does what, though; the thumb lever shifts to larger sprockets
and the index finger lever shifts to smaller ones, unless one of the
special rear ders is used. (Those are called "low normal", or
sometimes "rapid rise" ders. When you used the term "rapid rise"
above, I thought that your friend's bike had one, but your description
of the action fits a normal der, not a low-normal.)
--
Typoes are a feature, not a bug.
Some gardening required to reply via email.
Words processed in a facility that contains nuts.


 




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