I am a newbie and stuck in coaster brake mentality. I recently purchased a Schwinn Avenue (read inexpensive or cheap) Cycle with Schimano 7 shifter,( yes it came in a box and I assembled it wish I had the video of that). However it run well but, I cannot get it to shift from the small chain ring to the second chain ring (falls just short) it will shift from one to three OK and three to two to one OK. I have tried adjusting the cable tension and also the H L screws but she is just not making the shift. Any suggestions?

Is the derailleur set low enough?

Cage is correct height and cage aliggs with the chain rings. H L adjustments look good as to cage clearance, I just am confused as to why it does not go 1-2 buy will go 1-3 or 3-2-1.

All of the Shimano STI triple capable ROAD shifters that I've seen have 4 main shift positions and most have an additional "soft click" position for the smallest chainring. Normal operation requires that you go from the small ring position to the third main position to lift the chain from the smallest chainring to the middle chainring. This can be done with one good shove on the brake lever. Don't try to ease into it. Give it a big shove. Once on the middle ring you can trim the derailleur to either the second or third position to avoid chainrub. With this setup there will always be two positions for each chainring.

Al

Try adjusting the cable tension setting a bit tighter, that should help it make the step, then check that the chain clears the cage when feeding from the various cassette cogs you'll use the middle ring with. You might have to fiddle a bit to find the best balance between shift response and chain clearance.

Once you've got the middle ring shifting OK from both directions, use the H and L limit screws to set the final trim on the inner and out rings.

Thanks. I am going to put the chain on the front middle chain ring and back largest sprocket and then adjust cable tension at the shifter to ensure that the cage is correct and she shifts up and down to the middle chain ring, after that I will adjust H L screws for the small and large chain ring. Wish me luck.

Let's stop guessing.

https://www.parktool.com/repair/readhowto.asp?id=75

Start from step #1.

Been there, Done that, got the "T" Shirt and the Mug.

Let's see some pictures of cage rotation and alignment

Here is a fix-all Copy & Paste dealing with installing a FD properly:
____________________________________________________________________________________________________ ___

Take the cable off the FD. Now install it from scratch as per Park Tool Repair:

https://www.parktool.com/repair/readhowto.asp?id=75

And BicycleTutor:

https://bicycletutor.com/adjust-front-derailer/

When you have it properly trimmed and are ready for the cable - a new one wouldn't hurt - you want to pull the cable taut - not too tight, taut. Then apply 48 to 60 inch-pounds to the pinch-bolt. Then put it through it's paces.

It's always easier and faster to install a FD from square-one, than it is to make adjustments with it already attached. This tends to fix one thing - while throwing another out of kilter. Start fresh. You'll get it.

Adding an inline barrel-adjuster can solve many problems with the cable coming loose - or being too tight.

Barrel Adjusters:

https://www.biketoolsetc.com/index.cg...rrel-Adjusters