Roadwanderer

First, a little background. I'm on an old Univega 10-speed road bike from circa 1980 (give or take a few years).

The freewheel is the original equipment.

My derailleur can handle a 6 speed freewheel, or possibly a 7 speed.

One of my long-term goals has been to fit this bike with a chain-guard to protect my pants from the chain. The problem with that is that I can't find a chain-guard that will fit my 52T chain-ring and accommodate my front derailleur.

I can, however, find one that will fit a 48T with a front derailleur.

The problem I now have is that if I switch to a 48T chain-ring, I will lose gear inches on the top end. And I'm not willing to do that.

No problem, I say to myself. If I replace my 5 speed 14-28T freewheel with a 6 speed or a 7 speed with a 12-28T spread, or even an 11-28T spread, I can preserve, and even improve upon my current gear ratios.

Except there is a problem.

I can't find any freewheels answering to that description.

Except this one. Which would be perfect if I wasn't concerned about quality control (the reviews suggest it is lacking).

https://www.amazon.com/DNP-Epoch-Fre...1-28+freewheel

So any suggestions about how to bring my plans to fruition.

I actually need to replace my entire crankset at some point. It's almost as old as I am. And the large chain-ring is bent slightly.

Roadwanderer

Or should I upgrade to a cassette? How difficult would it be to convert?

Barabaika

Your bike has a 5-speed freewheel. It means that your rear frame spacing is 120mm. You have to respace the rear triangle wider to 126mm in order to install a 6-speed freewheel.
If you want a cassette, you have to respace to 130mm and build a new wheel.

I think you can open your 5-speed freewheel and change individual cogs to your liking.

Jeff Wills

Back when freewheels were more common, a 12-28 7-speed freewheel would have been pretty rare. It would have to be a SunTour New Winner or Shimano Dura-Ace or Santé. 12-28 was not a "stock" arrangement, so it would be a custom build by a shop that had the necessary spare cogs. 6-speed 12-28 was possible with SunTour New Winner, but I never saw one built that way.

I did this kind of stuff back when I was working in a shop... 35 years ago.

dedhed

Most readily available freewheels start at 14

HillRider

Shimano used to offer a 13x28 6-speed freewheel and a Google search for "Shimano Freewheels" turned up a 12x30 7-speed.

As noted, your frame is likely spaced 120 mm and 6 or 7-speed freewheels/cassettes require 126 mm hubs so you will have to either "cold set" (read: bend) your frame or struggle with the wheel each time you remove or reinstall it. Also, your current wheel will have to have the axle recentered or, better, a longer axle installed for the wider spacing. Even better would be to purchase a new wheel with a 7-speed freehub and use a 7-speed cassette.

JohnDThompson 

If you're concerned with losing high gears by switching to a 48T chainring, your best bet is to use a cassette hub in the rear. Freewheels with 12T small cogs are rare, and 11T cogs nonexistent.

fietsbob

Expect no smaller than 13t 13:53 was what they had racing, then ..

(Sachs Malliard , had a 12, for the 8th, threaded into the 7th, which threaded onto the freewheel body,

quite unwieldy, have to take cogs off to remove the freewheel [to replace a spoke]

hermanchauw

Pretty limited choices if you want to keep using freewheel. If your frame is steel you could spread it out to 135mm and use a modern freehub wheel with an 8 speed cassette. More choices in cassette size.

nfmisso

Instead of going down a path for many $$$; how about a Driveline chain guard?
Driveline Crank Chain Guard Road Bike 52T BCD 130 Black Cycling | eBay

CliffordK

I've got a DNP Epoch freewheel on my cargo bike (2 or 3 years now). I don't have a lot of miles on it, but many of those that it has done are HARD miles. So far no issues with it. The only note is that it is slightly wider than other similar freewheels (more spacing on the back side).

A cassette would mean building a new wheel. You'd have to decide what dropout spacing you want (126 vs 130). 7 speed cassettes are a little rare, but I think still being produced.

On one bike, I have 9 speed, 126mm spacing, all using an off-center rear rim.

davidad

These only go down to 13 teeth. Classica Freewheels 5/6/7-Speed ? Interloc Racing Design / IRD

Roadwanderer

That is my main concern--preserving my gear ratio. I like what I've got now and don't want to go backward. But I also don't want to continue sacrificing pants to bike chain grease, so a full chainguard is a must.

Maybe I'll try the Epoch out. How noisy is yours? My current freewheel barely makes a sound.

I've seen several 7 speed cassettes in production that will do (12-28). I wish they had a six. I just don't use that many gears. I'm usually either in the highest gear or the lowest and only use one or two in between (usually when I'm transitioning back to the highest) (we have a lot of steep hills and a lot of flat spaces where I live).



Yeah. That would put me down to 99" and change for the highest gear, which is lower than what I have now, unfortunately.


How easy is that to do? And does shimano make a 12 or 11T cog I can sub in? I like my current freewheel and would keep it if it were an option. And as I said above, I don't need that many gears. A 10 speed suits me just fine.

hueyhoolihan

i don't think the OP is being realistic WRT the gear inch question. i would suggest he or she take a few minutes looking closely at a gear-inch chart WRT speeds and RPM and then objectively consider their physical condition, and their intended use for the bike.

IME, the difference between a 48t and a 52t chainring may not even be noticeable, much less of any practical significance.

BTW, it would be interesting to have a pic or link to the chainguard being considered.

rccardr 

Couple options here:
1) have Pastorbobinnh make you a custom freewheel, but smallest cog would be a 13. BTW, I have a 48/34 13-28 combo on my Cannondale SR and don't spin out until well over 30mph. I really like the combination, even though I have other bikes with a 50-11 option, which gets used rarely. And we have steep hills and downhills here as well.
2) lace an 8-9-10 speed hub to your existing rim or buy a new rear wheel. You would have to get your dropouts spread to at least 126-128 if they are currently 120, but it would give you many options into the future. A 6 or 7 speed HG cassette is easy; 7 speed ones are out there but personally I would buy a ten speed one, drop the cogs you don't want and buy some six or seven speed spacers. You'll need to put a 4.5mm one behind a 7 speed ucassette.
3) buy a one shimano tricolor 126 OLD freehub that takes both HG and UG and make your own 6 or 7 speed cassette as above; no need for a spacer on 7 speed, will need one on a 6 speed.

maddog34

don't even try.

here's how i keep my pants out of the chain... i stuff the drive side pant leg into my SOCK. "i don't wear socks", you say?, then find a velcro'd strap, and put it around the bottom 2" of your pant leg... "but it will get lost!"... when you remove the velcro strap, place it around the upper tube of your bike frame.

OR... just wear shorts ALL the time, like i do... even in the coldest winter weather. Be bold, start a fashion trend!

Barabaika

Yes, almost no chainguards work with front derailleurs.

Barabaika

I don't think you need a 48->11 combination in Florida. It's for spinning while going down a steep hill.

If you want a chainguard, use a single chainring crankset or install an internally geared hub.

Roadwanderer

CHAINBOARD SILVER 199 MM - SKS-Germany

You might be right about me not being able to feel a one gear inch difference.

I'm fit enough. I spend most of my time in the top gear. I am happy with the feel (I could handle a little more resistance), and I like that I can maintain a higher speed with less effort. I ride 6-10 miles per day, both for recreation/exercise and for running errands.

Roadwanderer

Roadwanderer

I already do that. It still manages to get my pants on occasion, and it only takes one brush.

And, as to shorts, no.

I wear pants, even in the hottest weather. I'm not a fan of skin cancer. Or sunburns.

fietsbob

fi;fy

Jeff Wills

Changing cogs on 5-speed freewheels was relatively easy- 30 to 40 years ago. Good bike shops had spare cogs, tools, and the knowledge to change them out.

Nowadays? You'd have to find a bike shop that still has a stock of parts from back then and a mechanic willing to take on disassembling a 40-year-old freewheel.

And Shimano never made a 6-speed freewheel cog smaller than 13 tooth. Sorry- they just don't exist.

fietsbob

Its all about inventory costs... Cog boards were done, kaput, in the 80s, but the cost of shipping a box of cogs
and a box of ready to use freewheels is the same , it just stopped being adequately profitable..

70sSanO

Sachs made a 7 speed 12-30 freewheel. I found an NOS one a couple of years ago. Only problem was the 12-14-17 gearing. But if you can find one, eBay, it should work. Sachs Aris freewheels from the early 90's are pretty bulletproof.

John