Alright, please forgive my ignorance because I’m totally new to bikes in general and of course picked myself quite a difficult project to start with. I purchased a used Gaerlan collapsible and would love to fix it up and get it to the point where it’s a reliable/modernized ride.

It came equipped with out dated Suntour front/rear derailleurs and friction/indexed shifters, and a 7 speed freewheel. It was not shifting smoothly no matter how much we tuned it with the old parts. The guy that was helping me said I could consider switching all of the components to better engineered Shimano parts… so that’s what I did. He said any old 7 speed freewheel would do (d’oh!). I purchased the following:

Amazon.com : Shimano Tourney 7Spd 14-28T Freewheel : Bike Cassettes And Freewheels : Sports & Outdoors

Also purchased used Shimano Deore LX rear derailleur and shifters. With the new freewheel installed the chain now rubs the frame (it's too wide), but even worse, the gearing is just terrible. The tallest gear hardly moves the bike at all and I’ve largely got 21 worthless gears. It’s barely rideable.

To make matters worse, when we took the hub off of the rear wheel we also saw lots of grinding and pitting where it should be smooth. The guy helping said it's just about impossible to fix this short of replacing the wheel. I repacked with grease and installed new bearings, but that’s about all that could be done at the moment.

So gurus, what are my options? Are they to stick with the worn hub/rim I’ve got, find a 7 speed freewheel with the proper ratios that will work with the Shimano Deore LX components? Or replace the 451 rims with something more modern and switch over to a cassette with appropriate gearing? Would love to hear what you think is appropriate.

Attached are a few pictures of the original Suntour freewheel.

No ideas? Just cleaned up the old freewheel and counted the teeth...

12-13-14-16-18-20-23

If you want to use your high gear I'd add two washers to the axle, one on either side (fairly thin) to space the gear out from the chainstays.

To be honest, your main problem just sounds like you need to dial in your drivetrain. I.E. check cable housings for kinks, bends with too sharp of turns etc, friction in general in the cabling... also since you say you're new I'll just name off some basics, like setting the high-low limits on your mechs is very important, as is the proper cable tension

Thanks for the response. Assuming I'd stick with the 14-28T Shimano freewheel I'd probably go the spacing route, but the bike is largely unusable with that gearing... so I imagine I will need to switch back to a 12-23T freewheel of some sort... thus eliminating the chainstay/rubbing issue.

I guess my real concern is whether or not a Suntour 12-23T freewheel will work with a Shimano Deore LX 7 speed rear derailleur... And if not, is there another 7 speed freewheel or cassette that anyone is aware of that would? Even if it involved picking up a new wheel set or replacing the existing hub to a cassette setup, I'd be interested in hearing about it.

You're totally right though - sharp bends/kinks in the housings are having something to do with it. To remedy this I ordered some S&S cable splitters, so I am able to completely separate the front and back of the bike when taken apart and not put any stress on the cables by 'folding' the bike thereby putting them through too much stress.

7-speed Shimano indexing will not work with an old Suntour freewheel. Since you're not happy with your Shimano freewheel, I think your best bet is to get a new cassette wheel spaced for 8/9/10-speed. Make sure you know the spacing of the rear triangle before purchase, it's probably 130mm, which is considered road spacing now. A lot of hubs will have mtb/touring spacing of 135, so watch for that. You'll need a new shifter to match the cassette, too. That LX derailleur will handle 8- or 9-speed cassette/shifters, and there's tons of gearing options for them.

Friction shifting FTW ..

Now Replacement freewheels get the teeth stamped like a Hyperglide cassette Cogs ,
so they do pick up the chain to downshift quicker.

Swapped back the old Suntour freewheel, shifters, and rear derailleur yesterday. Indexing works (albeit poorly cause it's Suntour!), but yeah, I'll just have to get by with friction shifting for now...

Given the poor state of the rear hub, after doing some research it seems the following may be advisable: either rebuild the existing wheel (which I have never done and probably would take me forever) with a new 8 speed hub, or purchase a new wheel set with a modern 8 speed hub and find a narrow cassette with something like 11-23 or 12-23 gearing. Does something like that exist? And even if it doesn't, is it too difficult to assemble your own cassette? Given that I want to stick with 7 speed everything so I don't have to change my shifters that I JUST purchased, it's alright to use a 7 speed cassette on an 8 speed hub as long as you use a spacer right?