Bicycle Mechanics - Having trouble with STI shifting

I've got RSX Sti shifters and when I try to shift my rear derailleur to a higher gear, the small right-hand lever will often but not always swing inward without any tension and of course not produce a shift. Sometimes you have to press inward on the right-hand small lever two or three times before it goes into a higher gear. Using the large lever, you can always shift down without a problem. At first I thought it was just that my cable had stretched and so using the barrel adjuster took out some slack but that didn't really help that much and of couse if I put too many turns counter clockwise, then sometimes it will shift but skip a gear. Also would this make sense that a cable is too loose when you can always shift down a gear with no difficulty? Alright, now you can tell me what an idiot I am and reveal to me what should be so obvious. Thanks

Shift all the way up to 8-9-10 what every your hardest gear is.
Undo the cable at the derailleur, screw in the adjuster on the derailleur all the way, then back it out 3 full turns, then screw the barrel adjuster on the shifter all the way in and then re-connect the cable.
Then start adjustments from there

An old RSX right brifter not upshifting? Been there, sone that, and fixed it. Hold the brake lever down, then spray chain lube into the top section of the handle, where the shifter mechinism is. Spray more then you think you should. Then try to upshift. I rehabbed an old RSX brifter with this method and spread this advice in this forum before with success. If the search was working, you'd have my backup.

You can try cleaning and lubricating the shifters (I use WD40 for this), and you can try new shift cables and housings. But unfortunately RSX wasn't designed to last forever and ultimately you may need new shifters. On a friends bike we tried everything and eventually upgraded to 9-speed, new shifters, rear hub, rebuilt rear wheel, new cassette, new chain. Or you may be able to find new shifters in your speed (7?).

Al

Thanks for all the info. Yea, it's 8 speed. To change out everything and upgrade basically the entire power train, shifters, deraileurs, chain, crank, cassette would possible be more than bike is worth.

Thanks for all the info. Yea, it's 8 speed. To change out everything and upgrade basically the entire power train, shifters, deraileurs, chain, crank, cassette would possible be more than bike is worth.

Yes, that is often the case. Since it is 8-speed, you can probably upgrade to 9 or 10-speed without rebuilding the rear wheel, so all you would need is shifters, cassette, chain, bartape. That would actually make more sense than replacing the 8-speed shifters. I assumed you were talking 7-speed.

Al