Shifter Questions

[Dadx2mj]

Forgive my nooby-ness, I have a vast mechanical background but am pretty new to bikes.

I recently bought a 05 Giant Simple Seven it has a Shimano Revo Twist Shifter and a Shimano Tourey Megarange derailleur. I have replaced the shift cable and adjust the derailleur and ensured there or no bent parts etc to the best of my ability. The problem I have is that when shifting to a higher gear I have to shift the shifter twice to get the gear to change then back it off a click to keep it from making a clicking noise. It works fine when shifting down to a lower gear. It also has a tendency to skip one cog (2nd gear). I am thinking the shifter is worn out and needs to be replaced. Is there some other issue that could be causing this that I am over looking?

If the shifter does need to be replaced do I have to stick with the Twist Shifter or can I change it to another style like the thumb levers?

Thanks in advacnce or any help or advise.

 

[RustySprockets]

This sounds like a simple adjustment issue, not any real damage or excessive wear. The shift cables tend to stretch over time and use, and therefore, can lose tension. I'd first inspect and lube the cables and housings, then make small tweaks using the barrel adjuster on the rear derailleur. Tightening the adjuster will remove slack, move the cage slightly inboard, and eliminate that annoying clacking sound you report. If that doesn't solve the problem immediately, then find a video tutorial on derailleur adjustments--there are plenty on YouTube, etc.

 

[deorman]

Sounds as though you may have slack in your cable. If not obvious it could be stretched out radial core sheath ("housing"). Linear core works better for indexed shifters. Not a big fan of twist shifters. If you can't get it adjusted, old school friction shifters would work, but you should be able to get a Shimano 7-spd indexed lever type if you prefer.

 

[Dadx2mj]

Thanks for the replies guys. I just replaced the cable it is not even a week old. I have watched several tutorial vids adn was confident it was just aq matter of adjusting the cable tension but I have done this and adjusted it to the point of going too far and having to loosen it back up to get it to work as well has it is now.

I have the high and low end point setr properly or so I feel. I have cleaned the cassette and chain and re lubricated it, the deraileure hanger is straight and tight on the frame, the cable is new and in all the proper journals, I think I have the basics covered but still getting some odd shifting behavior.

 

[deorman]

But did you replace the housing? http://sheldonbrown.com/cables.html#compressionless

 

[RustySprockets]

Sorry, but the behavior and "clacking noise" you speak of is a clear indicator to me that the tension is still mis-adjusted. Think of the barrel adjuster as a fine-tuning knob that allows you the center the chain dead-on the sprockets. When it rubs on one side or the other, it grumbles. When the rubbing is significant enough, it skips gears. These are both symptoms you're reporting.

You've already addressed/eliminated the obvious culprits, so try following this four-minute video and see if you can't get things shifting smoothly again.

http://youtu.be/2j1gSwhsVN8

 

[Dadx2mj]

Yes the housing was replaced with the cable.

I watched the video posted thanks for the link. I have followed those steps but have no problem thinking since I am new to this I just did not get it just right so will give it another go until I get it just right. Thanks for the help guys.

 

[LukeTheJoker]

On more thing, are both the shifter and the derailleur original to the bike? They may not match, even coming from the same manufacturer, I have had that happen before...

Luke.

 

[Dadx2mj]

On more thing, are both the shifter and the derailleur original to the bike? They may not match, even coming from the same manufacturer, I have had that happen before...

Luke.

I believe they are but can not say for certain. I bought the bike off Craigslist and the owner really did not know much about it or it's history. That kind of brings me back to my other question about installing the thumb lever shifter on it, is that a possibility? For some reason I have just never been fond of the twist shifters.

 

[user 135]

Looks like it is all original. http://www.bikepedia.com/quickbike/Bike ... pKxOo1Q1xw

Thumb shifters are my favorite and I have on 2 out of my 3 geared bikes. Friction shifting allows you to fine tune.