Shimano RapidFire Shifters - education needed
 

I was recently volunteering at a church garage sale when the pictured bike came in. It is a Raleigh Touring Bike, 200 CT. It came with a Cat Eye Vectra Computer, a Headlight, and Nashbar Bottle Rack and Rear Rack with a Nashbar bag that had a repair kit, safety vest and a few other goodies. The bike was purchased in Florida and somehow made it to Texas. It was covered in dust as I assume it was stored in someone’s barn. I know a little about bikes so I kept my eye on it, because of the dirty condition and two “flat” tires it was marked for $ 10.00. I bought it at the end of the first night, took it home and cleaned it up. The bike has the following components:

• Shimano Altus A20 Rapidfire Plus
• Shimano Altus C10 Rapidfire Plus
• Shimano Altus C20 Front Derailleur
• Shimano Altus A20 Rear Derailleur
• Shimano Altus C20, 28/38/48 teeth

Question # 1 - I have no idea how the Rapidfire shifter works as each have two thumb levers. How do the shifters work?
Question # 2 - The front derailleur will shift from the low range to the mid, but will not hold and shifts back to low on its own. I cannot get the front derailleur to engage the high gear at all. Why is this happening?
Question # 3 - The rear derailleur will not engage at all, the shifter is very stiff. Why is this happening?
Question # 4 – The Cat Eye Vectra is not working; does anyone know of a link where I can learn how to change the battery and how the device functions?

1) One lever moves upshifts and the other downshifts. Take a minute to play around with it and it'll be obvious. Pedal it on a stand and actuate the levers.
2) Wouldn't be surprised that the shifter is broken. Also can be an adjustment issue followed by cable + housing issue http://www.parktool.com/repair/readhowto.asp?id=75
3) Again, on a bike that's been sitting for a while, you can almost guarantee that the cable + housing suck http://www.parktool.com/repair/readhowto.asp?id=64
4) All wired bike computers operate on nearly the same principle. Magnet attached to the spoke on a wheel passses by a sensor which is connected by a wire to the mount which is typically on the handlebars/stem. The computer sits there. Battery is secured by a cover usually, again on the rear of the unit. If it is fubar, new wired units with multi-line display starts at around $10-$15.

Your questions are not easy to comprehensively answer without at least a little bit of homework and effort on your part.

Cateye manuals: http://www.cateye.com/en/manuals/66

I have a 2000 KHS tandem with Shimano triggershifters and newer bikes with SRAM triggershifts. Generally, one trigger on each side goes up , the other goes down. Yours look different but probably work similarly.

I would suspect that your cables and housing could stand to be replaced and if you do that and then adjust them, all will work.
http://www.parktool.com/repair/byregion.asp?catid=53

Spending $10 on the bike (quite a deal!) allows you to spend whatever it takes to make it right.
What is the frame make of?

Quite a good deal, judging from the picture alone it looks like it was taken care of - it has a rack on it that is level, and everything looks like it's in generally good condition. You'd have to spend approximately $400-$600 to get something of that quality new. Assuming nothing is fatally beyond repair.

Typically, the grease in Rapidfire shift levers that have sat unused for long time turns to hard, sticky gum. To restore them to usefulness, find an opening in the shifter cover and hose out the insides with spray lubricant. Use a "real" lubricant, not WD-40. Work all of the levers, and you'll feel them catching and releasing the cable. Crank the cranks and you should start to figure out which lever makes the chain shift which way.

The Park Tools pages are good for basic diagnosis and repair: http://parktool.com/repair/

Thank you very much, the parktool website is awesome. I will try the spray lubricant also, what do you recommend?

Thank you very much, the parktool website is awesome. Just what a novice mechanic, like me, needs. Does Shimano spare old shifter parts? I assume the bike to be at least ten years old!

Thanks for the Cat Eye manual website also.

Not only that but the seat is at a reasonable angle and not slammed as low as it will go. The bar ends are also oriented at a usable angle, a very rare occurrence as well. Nice find.

WD-40 works well as does any silicone lube. Neither will harm the plastic bits in the shifters.