Fkirschfink

Hi Everybody,

A couple of months ago, I bought this bike for around 70 USD to use it as everyday transportation and have a couple of fun rides on the weekend.

It has worked great so far, but I'm interested in replacing the 5 Speed Freewheel that came with the bike (13-21 Relation) with a 5 o 6 Speed Freewheel with a larger relation (13-28) so I can climb the hills in my city easier.

At first I thought about upgrading to 8 Speed (which implicated upgrading many other parts) but it's seems easier to add teeth to the Freewheel (I don't really need "more" gears, only the same ammount of gears with a "softer" relation).

Since not many local Shops are familiar with vintage bikes, my question is: ¿Is it possible to just replace the Freewheel (with the same nº of speed's) and keep the same rear & front derrailleur, chain and friction levers?

What should I look after in terms of compatibility?

I was thinking of the Shimano MF-6208 6 Speed Freewheel as my main option (maybe later set a 6 speed indexed shifting)

Thank you very much !

Arrowana

Your bike appears to have a Uni-Glide cassette rather than a freewheel. Uni-Glide isn't made anymore, and finding a 5 speed Uni-Glide cassette might be rather difficult. A freewheel will not fit. If you wish to get a lower gear, your best bet would be to either swap the rear wheel for one that takes a freewheel or a modern cassette, or to swap the crankset for one with smaller chainrings. Your rear derailleur will likely work with up to a 28t cog, you would need to swap it out if you want to go even bigger. Swapping to a larger freewheel or cassette will require a longer chain, and it would be best to get a new chain to work with the new freewheel or cassette anyways.

Kontact 

You could buy a 7 speed Hyperglide cassette and grind down the one big spline per cog necessary to mount it on your freehub body, but you will have to reuse your smallest cog to tighten it all down. The result will likely not be 7 speed, as you'll have to pick and choose what will fit. But with a Dremel tool and less than an hour you could make it happen.

52telecaster

I do the same with a file. These hubs are wonderful opportunities to explore different gearings. You will need two chain whips.

mpetry912 

is that rear wheel built FIVE cross ?

the good news is it looks like you have a fair amount of room to play with (rear spacing)

I'd just look for a complete wheel to replace it.

you might want consider some new pedals too

/markp

Bianchigirll 

Where do you live? Look for a bike co-op or recycler and maybe you can scrounge some cogs to fit that old cassette.

I’d be a bit concerned about how that dropout is spread open.

pedals?

The replacement wheels a good suggestion and here again a co-op place that sells used good bike parts is where to look first.

merziac

@Fkirschfink

That RD needs to be deleted asap IMO, then very carefully address the jacked open drop out and find some good replacement's for the RD and FW

dddd

I haven't messed with any five-speed cassette hubs, but on a similar model six-speed Uniglide cassette hub, I found that trying to use a 7s cassette didn't give near enough threaded engagement for the smallest cog.
So I don't think that you will be able to use even six out of seven cogs from a newer 7s cassette.

You can use Hyperglide cogs (all but the smallest one) with just one spline cut down using a file, but adding more than five cogs to this freehub would require 9s-width spacers and similarly narrow chain. I don't think it would friction shift all that well with the derailer that's on there, and the 9s chain likely wouldn't play nice with your existing chainring spacing.

Sadly, this is kind of like being stuck with a Helicomatic rear hub, quite limiting in other words!

One good bit of news is that your rear derailer would probably handle a 32-tooth largest cog, I'm using a similar Lark II rear derailer with a 34t largest cog and only the lightest bit of rumble caused the the pulley teeth touching the tips of the largest cog's teeth.

Kontact 

No one said he has to go over 5. But that still solves the gearing and cog replacement problem.

repechage

It has a freehub- there are a few approaches that will get you a wider range, and an additional cog or two, they do require effort as mentioned.
there are other concerns that can be seen- that rear derailleur might not handle a much wider ratio, the chain may need to be longer.
that pedal, or what’s left of it is a notable problem as others have advised.

a sympathetic bike shop or a bike co-op would be an avenue to pursue- you will need some tools- nothing dramatic but necessary.

a later 6200 series freehub will help but probably need frame width adjustment.

the bike equal of Wristwatch Revival on YouTube

Hondo6

OP's profile gives a location of "CL", which is the ISO Alpha-2 code for Chile. His/her location may complicate things significantly regarding parts availability, cost, and availability of local co-ops.

Fkirschfink

Thanks everybody,

I'm learning my first bits about bike replacement parts so all this information is very useful.

I already replaced the pedals, pictures are a couple of weeks old 😊

As someone said, Im from Chile, but thats not a big issue as Im receiving packages from the US & Germany every month (It's just easier to transport a freehub and/or a cassette than a full wheel)

Would It be to much to ask for an eBay reference for a recommendable freehub and cassette/freewheel combination? (Nevermind the price)

I also would apareciate a lot some more enlightment about the problem regarding the dropout and possible Solutions.

Again, thanks everybody for your time !

Fkirschfink

Also, of course I'm interested and Will take note of any other suggestions that might upgrade the ride experiences (RD, for example).

Good night to all !

merziac

Keep in mind the jacked open RDO/rear drop out. is the first thing that should be corrected, it and the hanger for the RD must be aligned for this to move forward, they are the foundation that much of what you want to do are based off of, especially if you are going to push the limits along the way.

And it must be done carefully, if it is forged as I suspect, it may be easier to break than correct.

davester

Sheldon Brown has an excellent page on Uniglide/Hyperglide compatibility and solutions here: https://sheldonbrown.com/k7.html

As far as the bent rear drop out is concerned, in case you don't know, both top and bottom surfaces of the dropout should be parallel, just like the left side dropout. I'm guessing that the rear derailleur got caught in the spokes and got pulled backwards, which bent the dropout open. This happened to a friend of mine a couple of years ago...his dropout looked much worse than yours and he bent it partially back so that it now looks like yours. I think that you could leave it alone without any problems, though if it was my bike I'd probably get a "C" clamp and try to close the dropout at least partly. Be careful though...if it breaks while bending it back the frame is toast.

That said, the more important issue regarding a bent dropout is whether the derailleur mount is still parallel to the wheel. There's a specific tool for measuring this but if you don't have one you can probably get a good idea by looking at the derailleur cage from the back to see if it is parallel to the chainrings. Also look from above to see if it is bent in the fore-aft direction. If it is not straight then you would need to remove the derailleur and straighten the drop out with a crescent wrench.

Regarding the derailleur, it may work fine but it is an ultra cheap model and I would change it for something better for that reason alone. My guess is that it was installed after the old derailleur was destroyed by getting caught in the spokes, as I mentioned above. However, replacing it is not absolutely necessary and I would guess that it will accommodate a much larger cassette (I'm guessing 28T).

Kontact 

Considering that he has the axle all the way in like a vertical dropout, I don't know if it is smart to risk breaking it by bending it back.

Though it is "improper".

70sSanO

This is the way to go. There was a retailer Loose Screws that has, used to have, Uniglide threaded first position cogs. I’ve run a UG first cog with a HG cassette. The important part is getting 34.6mm thread and not a 32mm Dura Ace only.

As for the number of cogs. With friction you can run whatever you want; up to a point. Based on available chain and shifting ability. Take a 7 speed cassette apart and sand the plastic spacers to fit.

John

Kontact 

For most people that don't ride around in the crossover, the high cog lasts forever. I just doesn't get a lot of use, and rarely high torque use. But that's cool someone is selling them.

Highmass

I believe that this is a 6207 hub. I´m not sure if it´s been modified (Spacers removed) to make it fit a 120mm frame, but the important thing is, that this hub came with a 6 speed cassette. So if the op finds a 6 speed hub, the freehub part can be transferred to the current hub, making use of 6 speed uniglide casettes (Much easier to find than 5 speed) possible. But personally I´d prefer to transplant the freehub part from a 126mm 7s hyperglide hub, and remove some spacers to make it narrow enough

Fkirschfink

Hi Everyone,

Again, I'm so grateful for all your help and opinions/experiences.

Like I said, I'm still on Bike 101 so every explanation counts (as basic as it seems).

As for the bent dropout, I tried to point out what I think you are suggesting. Red arrows would be the "bending" direction needed and Red Stripes are the parts that should be parallel?? Please let me know if I got it wrong (I wont touch the frame until I find someone with the know-how).




As for the Hyperglide Cassette solution, I saw this video and it helped me undestand better what you meant:

You Tube

I'm debating on either trying the Hyperglide solution with my actual Hub (which would only require a 7Sp HG Cassette & a Dremel/File) or buying this Wheel with a 6 Speed 14-24 UG Cassette installed (50USD): https://www.facebook.com/marketplace...l&locale=es_LA

In both scenarios I would replace the RD for a better one as soon as I choose what Cassette I will use.

For now, I'm inclined for the Hyperglide convertion, as it would be easier replaced in the long term, and It would assure me a bigger Cog relation (14-24 is pretty similar to what I have and I would still be stuck with Uniglide).

Thank you all !

70sSanO

As far as rear derailleurs, one of my favorites for a "close to" era is an RD-MT60. I have a bike running a 7 speed with a 34t.

It will handle any range you want and it looks similar to an RD-6207 that was released in the early 80's.

It may take a bit of looking on eBay to find a nice looking one. They used to be dirt cheap, but I imagine they are more expensive these days. You can still get replacement pulleys if needed.

John

Fkirschfink

Thank you for your RD recommendation 70sSanO

Sooo to slowly wrap up this thread and not be keeping your attention forever, I take the following conclusions:

1. As for the bent Rear-Dropout, I feel I understood what the issue is and how it could/should be treated (It would be great anyway if somebody could confirm my drawing in the last post). When I'm certain about the problem/solution, I will look for help (won't touch the frame by myself)

2. As for the necessity of installing bigger cogs and what you've told me, I think I might have at least 3 options:

a) Keeping the build "Uniglide" and buying a 5 o 6 speed cassette with bigger cogs that will fit my actual Hub. Something like this should work???:

https://www.ebay.de/itm/126301550648...Bk9SR8yKu_C8Yw

b) Going 7 Speed Hyperglide Cassette, sanding sprockets & spacers to make it fit my actual Hub and re-using my actual smallest cog for closure. Something like this might work??:

https://www.ebay.de/itm/314402640403...Bk9SR9iGyvC8Yw

c) Building a whole new rear-wheel with a Hyperglide compatible Hub. Something like this???:

https://www.ebay.de/itm/395122432067...3ABFBMirLU8Lxj

3. In any case, replacing de RD and chain to make a better fit with the chosen Cassette & Hub.

I think I might have gotten it right but please correct me if I didn't.

Thanks again for reading and helping !

merziac

Yes, your assessment is good but the RD isn't really a factor in the bent and as it pivots is removed to address the RDO.

Its not that difficult but requires a steady hand and good understanding of the forces at play.

It has been addressed here at times and really only requires the right tool, patience and again, steady hand.

Paging @gugie

Hondo6

FWIW: I don't know if anyone's suggested it yet, but for the OP's rear hub a freehub transplant using a 7-speed Uniglide or Hyperglide freehub (which would allow direct use of a 7-speed cassette of the appropriate type) may not be feasible.

In looking at the OP's rear hub photos above, one shows nearly the full hub barrel. The OP's rear hub appears to lack any bulge at the freehub (drive-side) end of the hub barrel. It also appears to have a date code of "ED", which I am fairly sure translates to a manufacture date April 1980.

This combination (lack of bulge on hub barrel plus Apr 1980 manufacture date) implies the strong likelihood of it being an early Uniglide hub. Such early Uniglide hubs were available in both 5- and 6-speed and use a unique attachment method for the freehub (slip fit over smooth hollow cylindrical projection vice a threaded hollow Allen bolt). Due to this early design difference, such freehubs cannot accept a Shimano freehub using a later design.

The late Sheldon Brown discussed this in his article titled "Shimano Hubs & Freehubs". See the end section of the article titled "Early Uniglide: 1970s-early '80s".

That's a pity. Transplanting a 7-speed Hyperglide freehub might otherwise be a relatively elegant solution to the OP's issue, allowing direct use of a 12-28 or 12-32 HG-200-7 cassette (which are still available).

Edited to Add: if the OLD for the OP's hub is 120mm, such a swap would of course require a new rear axle as well (137mm for 126mm OLD vice 131mm for 120mm OLD).

gugie 

Closing up that gap on the dropout is easily done with an 8" crescent wrench. I imagine in Chile you can find a 200mm model. The trick is to use the hole on the end (typically used to hang the wrench off of a hook.) Use the open area of the hole in the wrench to catch the stop on the derailleur hanger.

Red arrow points to the stop:



8"/200mm adjustable wrenches have a "just right" hole at the end. Smaller or larger adjustable wrenches don't have the right hole size to do this.

Just tug on tne wrench carefully, a bit at a time until the two faces are parallel.

One you do that, getting the dropout faces parallel and derailleur hanger aligned properly are next. Sheldon Brown