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Used Giant Rincon needs help
#1
Bought a used bike for my 12 yo and it needs some things. Overall it seems ok and my son loves it, but the chain kept coming off the front gears when shifting. I figured it needed to be adjusted and went after that today. Turns out the shifter has more than three positions. It moves the derailleur in seven small increments just like the rear derailleur. I can turn the shifter, grip shifter, three clicks and it shifts ok. Somebody used what was quickly available.

So, I turn to ebay for replacement shifters, I'll need to change both for them to match. New issue, the brake levers don't match either, one aluminum and one plastic but the brakes work fine. Now that I know there is such a thing I'm looking at shift brake combos. Unfortunately, most, almost all, are for eight or nine gear rears and I need seven.

Questions:
1 Can I buy an 8, or 9, gear cassette and expect it to work with my frame?
2 If yes to 1 does that mean a new rear derailleur?
3 What would you suggest?
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#2
Is the bike adult sized? Is it a decent quality frame? If no, don't overspend.
  • Shifter: The left shifter usually has more than three positions, this is for something called "trimming", where you move the front derailleur a bit to avoid chain rub. Can be confusing at first.
  • Brake / shifter combo: Why? I like being able to replace parts and to adjust brake lever and shifter position independently.
  • Brake lever: make sure the lever matches the brake type: Don't use a lever for cantis with V-brakes (or the other way round). What type do you have?
  • When replacing everything, you'll end up spending a lot of money. You'd need to replace: Shifters, derailleurs, chain, sprockets, freehub body (if it can be done) and probably the crank set (maybe also the bottom bracket?) and maybe also the brakes if you go for new components. (Additionally: cables, housing, brake pads)
    • Cassette and chain are consumables, you'll need to replace them eventually anyway. Check for chain wear!
    • The rear derailleur might be worn out, depending on how long the bike has been used and how it has been treated.
    • If the chain wheels are worn, they need to be replaced, too
    • If you have a freehub where the body can be replaced, this is going to be inexpensive, otherwise you'll have to replace the freehub or the rear wheel.
    • Brakes: Replacing Cantis with V-brakes is a good upgrade.
Here is what I would do:
Check for chain / sprocket / chain ring wear, look at the rear derailleur, check bottom bracket for play. Look at the brakes. If the chain wheels, bottom bracket and rear derailleur are still ok, replace the chain and sprockets (used bike: most likely this has to be done). Maybe upgrade from cantis to V-brakes (if applicable), I'd probably do that, but replace the brake pads. Get a used left shifter, if you cannot make it work. Replace the cables and housing.
When everything is worn: Try to replace as few parts as possible and save the money to get something decent in a few years.
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#3
1) Is your rear "cluster" a "cassette" type or "screw on"?
http://bicycletutor.com/replace-cassette-cluster/

2) If it is a cassette then I'm not sure if the "freehub" is long enough to take an 8/9 speed cassette ??
http://bicycletutor.com/freehub-body/

(Generally, depending on the make, 8 & 9 cassettes will fit the same freehub.)

3) The frame is probably wide enough to take an 8/9 speed setup.

4) 7/8/9 speed shifters are not interchangeable - an 8 speed changer won't work properly with a 7 speed cassette and a 9 won't work with an 8. (different spacing on the cassette.)

5) Shift/Brakes come seperately as well as in combo's.!
Some brake levers are designed for "Vee" brakes and some for "Cantilever" types. They have different pulls and don't work efficiently if mixed up.

6) The front derailleur can be adjusted to stop the chain coming off using the 2 "limit screws":-
http://bicycletutor.com/adjust-front-derailer/

7) You might get away with your existing derailleur depending an make and model?

You really need to weigh up the cost of replacement components to see if it's viable. Sometimes a "newer" complete bike might cost less!

You might try matching the aluminum brake lever and keeping the shifters. ?????

It's also helpful if you state the make of your components -
(Shimano / Sram etc.)

If you need any thing explaining then please ask.
[font=Trebuchet MS]Ride hard or ride home alone![/font]
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#4
Thanks for the repplies.
Bike info
Frame is 17" aluminum
Wheels are 26"
Brakes are V type, function well
Front derailleur is Shimano Altus, seems to be ok
Rear derailleur is Shimano Acera, seems to be ok
Grip shifters are Sram Max Plus, front odd rear ok, see below
Cluster or cassette, not sure can I tell without taking it apart?
_________________
Shifters are not interchangeable, understood.
"Left shifter usually has more than three positions", so do you just click through until you line up with the number you're shifting to? Strange, neither mine nor my wifes does this.
Keeping cost down, understood. Except for changing the front gears the bike functions well. I just wanted to change the brake levers to make them uniform. What I'd like to do is find both shifters, preferably 3/7. Change the two brake levers, V type, and cabling where needed.

Questions:
1. Shifters I have seen come with cables, can I just re-use the existing cable sheaths.
2. Brake levers don't seem to have cables. Can I buy a length of cable and cut to length? What about where it terminates to the hand lever?
3. Can I re-use the brake cable sheath?

Thanks for the help.
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#5
Shifters for left (front) usually have 3 positions for the Altus (Shimano MTB ) groupset.
The Altus changers are available in both 7 or 8 speed.
Maybe as you say some one has cobbled together spare parts.

These are the Shiamno tech' documents for Altus.
http://techdocs.shimano.com/techdocs/blevel.jsp?FOLDER%3C%3Efolder_id=2534374302051836&ASSORTMENT%3C%3East_id=1408474395181679&bmUID=1243060307065

This shows the availability of both separate brake levers / shifters or combined.

( You do not have to use Altus but you can go to the higher grades of Shimano groupsets. Such as Alivio, STX etc. The only thing you must do is match the speed numbers - 7 with 7 or 8 with 8 and so on.)

The chances are you have a Shimano freehub / cassette unit.
See Sheldon Brown for an explanation:-
http://www.sheldonbrown.com/free-k7.html

If the cables and outers are in good condition and the right length then you could re-use them.
I sometimes remove the long cables to the bike rear and shorten them to re-use on the front.
The rear derailleur cable is the critical one for good shifting.
Derailleur cables are usually a little thinner than brake cables to allow for flexing.
Brake cables are thicker for strength.
Not only that but the end "bullets" (the part that fits into lever / shifter) are a different shape and size.

So, initially, do you want to keep the 7 speed or upgrade to 8 speed.
This will determine the model of shifter (7 or 8)?
Do you want separate shifter or combined?
If you go to 8 speed then you will have to change the cassette as well.
Both derailleurs can be kept and the chain stays the same.
If the chain is reasonably new then O.K. If not then a get a new chain especially if you fit a new cassette.

To DIY you will need a 3 "special" tools to do this.
a) Chain tool. (to fit new chain if required?)
b) Cassette and chain whip. (for removal & fitting of cassette)

See the videos for how!
[font=Trebuchet MS]Ride hard or ride home alone![/font]
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#6
@cyclerUK: Can you fit an 8 speed cassette on a 7 speed freehub?

Oh, and I have seen 7 speed freewheels on lower end bikes too often in the last years, so I'm not as optimistic as you are...

Quote:"Left shifter usually has more than three positions", so do you just click through until you line up with the number you're shifting to? Strange, neither mine nor my wifes does this.
Yes, that is basically the idea: line up with the number you're shifting to, the positions in between are for trimming. My brother's old grip shifters did this, too, but I cannot remember the type (it was a cheap bike, so most likely lower or rather lowest end of Shimano hierarchy). My Shimano 200GS front shifter (on my hybrid, early 90s Giant) also has trim positions.

Good luck!
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#7
Quote:@cyclerUK: Can you fit an 8 speed cassette on a 7 speed freehub?

Basically No!
Sorry, I missed that of the list, thanks for the reminder.

So if going for an 8 speed then probably need to fit a new freehub as well. The wheel then may need re-dishing to re-center it.
This then starts to increase the expense so needs careful thought.

So, if the decision is to go ahead, then determine if freehub/cassette or freewheel?
Next, if freehub, will it take an 8 speed cassette?
[font=Trebuchet MS]Ride hard or ride home alone![/font]
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#8
I think I'm just going to look for a 3/7 shifter set and V brake levers or combo of the two if more convenient.

Can I go with most any shifter style?
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#9
Not quite sure what you mean by "style"?
With Shimano derailleurs, if you stick with Shimano 3x7 speed shifters, you won't have a problem.

It looks like "new" 7 speed MTB shifters are only available in the Altus range now.

But if you come across any of the older Shimano 7 speed units then these will work with the 7 speed sprockets.
My first MTB units were 7 speed Alivio's, but gradually Shimano have been upping the ranges to 8 and then 9 speeds.
[font=Trebuchet MS]Ride hard or ride home alone![/font]
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#10
Bought new grip shifters and brake levers from Amazon today, due Monday.

Thanks for the help.
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#11
my friend's crap kmart bike has the front grip shifter that just clicks until you get up there....i find that good, and bad. on one hand, you don't have to adjust the front derailer if you're without tools if it gets out of whack, cause you can just click a few click backs or forward.....but yeah, its not as snappy. it happens. i wouldn't have bothered replacing them personally, its not worth the money, if you're not paying a lot for new ones.
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