I recently bought a 7 speed Biria bike with base model Shimano "Tourney" derailer and Revo "twist" shifter. This setup isn't very precise and often I have to "jiggle" the shifter to get proper shifts.

I also have a Specialized bike with better quality Shimano derailer and trigger shifter and shifts are always crisp and precise and I want such shifting for the Biria.

So what do you think is my best way to go? Perhaps simply better adjustment? A better shifter? A better derailer? Both? All advice is welcomed.

Thanks.

What's the condition of the Biria? I presume it's not new, so ...

Replace cables and housings first. Then get it adjusted properly. The twist grip shifters aren't precise to begin with but may be grunged up. The RD is heavy but quite usable. Work it with your fingers to see if it's sticky and if so lube the pivots.

DMF---The bike is new. I'm gonna take it to the dealer tomorrow and have him get things properly adjusted (if they aren't already) and go from there.

Thanks

Falcon Friction shifters: 15 dollars.

Sounds like your Bria needs its 30 day tune up. You're describing a slightly slack shift cable, not bad components.

Indeed Dan. I took the bike in today; the mechanic tightened the cable and now it's shifting fine.

Thanks for the replies folks.