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Discussion Starter · #1 ·
I have shimano LX Deore derailleurs, Teflon cables and rolla ma jig on a trek 4500.
I can't seem to tune it to shift correctly.
Top ring 1st gear wont shift to top ring second gear.
Middle ring first gear jumps to bottom ring 1st.

The bike shop dude said that shimano suggests that on the top ring only gears 3-8 are available. Middle ring gears 2-7 and bottom ring gears 1-6.
That sounds like hooey to me.
Any suggestions on how to get the bike shifting properly?
(I actually had NO problem with the original Alivio derailleurs, except scrapping against the front derailleur.)
Thanks for your input!
[email protected]
 

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You have to...

satgale said:
I have shimano LX Deore derailleurs, Teflon cables and rolla ma jig on a trek 4500.
I can't seem to tune it to shift correctly.
Top ring 1st gear wont shift to top ring second gear.
Middle ring first gear jumps to bottom ring 1st.

The bike shop dude said that shimano suggests that on the top ring only gears 3-8 are available. Middle ring gears 2-7 and bottom ring gears 1-6.
That sounds like hooey to me.
Any suggestions on how to get the bike shifting properly?
(I actually had NO problem with the original Alivio derailleurs, except scrapping against the front derailleur.)
Thanks for your input!
[email protected]
use the correct language if you expect a decent answer. Rear end of the bike has the cassette which is made up of individual cogs. The foward set are known as chainrings and easiest to understand when refered to as small, middle, large rings.

The suggestion for 3 chainrings is usually do not pedal/shift into small/small or large/large. Meaning don't shift into the largest cog/largest chainring, or smallest cog/smallest chainring as it will not only be noisy, but cause excessive wear. It should still shift into those gear combinations.
 

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Not sure

satgale said:
I have shimano LX Deore derailleurs, Teflon cables and rolla ma jig on a trek 4500.
I can’t seem to tune it to shift correctly.
Top ring 1st gear wont shift to top ring second gear.
Middle ring first gear jumps to bottom ring 1st.

I'm not sure what you're saying, but:

You should be able to shift to all the rear (cassette) gears using the middle chain ring in front. "Cross chaining" or big chainring to big cassette gear is the worst combination, and the little chainring to the little cassette gear is almost as bad for the bike. The extreme chain angle is very hard on the gears even if you can make the derailuer do the shift. So forget about those, you don't want to use these combinations even if you can shift into them.

If the problem is that the bike is shifting itself (ghost shifting), there are a number of causes. If the derailuer or mount is bent, or the derailuer is sticky, you will have to fix that problem before it will shift well. Dirty, bent or worn cassette gears can foul up your shifting too, as well as a worn or dirty chain. Make sure you have covered the basics first.

With new cables and housing, be careful to cut the housing to the exact length of the old pieces. It's not usually a problem with a hard tail, but bikes with rear suspensions can be very picky. You did use a cable cutter tool, right? A lot of shifting problems are due to poorly cut housings. Also, brake cable housing looks like shifter housing, but with index shifting, a different type of housing is used. You used the correct stuff, right?

Be sure to use the correct size ferrules on the ends of the cables.

Check the final job. Loosen the clamp at the derailuer and take everything apart again. Thread the cable through the housing one piece at a time and work it back and forth with your fingers. Make sure the cable slides easily through the housing.

If this doesn't help, consider taking the bike to your LBS. Hope this helps.

Walt
 

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Discussion Starter · #4 ·
Fixed...

Fred…thanks for making a newbie feel so welcomed. :rolleyes:

The bike shop ended up replacing the cable to the rear derailleur. They said the cable loop wasn't big enough at the back of it. I was ticked because they were the ones that put it on in the first place and they had to cut my Teflon cable to fix it. It shifted correctly on a short ride so hopefully all is fixed.
Lesson: just because a bike shop sells and services bikes their mechanics may not know what they are doing!
BTW: if you need a bike repaired in the Stuttgart area of Germany stay clear of Sportivo in Sindelfingen.
 
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