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-   -   Old crappy 5 speed to 6 speed (https://www.bikeforums.net/bicycle-mechanics/1144936-old-crappy-5-speed-6-speed.html)

unclejemima 05-23-18 02:51 PM

Old crappy 5 speed to 6 speed
 
My sons bike has a crappy old 5 speed falcon rear derailleur and grip shift. The bike has 20Ē wheels.

The derailleur is a pos from day one and has never worked good, and Iíve adjust it for hours and itís just a poor quality part. (And old)

My other son has a 6 speed shimano unit on his bike and it works great. I want to get something like that to replace the 5 speed on my other sons bike so his shifts and works nice as well.

my question is how and what do I order for a derailleur, cog set, shifter and chain? Iíve heard a 5-6 speed cog set are identical width and should interchange just fine, but can I use a shimano derailleur with say a sram grip shift?

at what point do the cog sets get to wide to work on a smaller kids bike? (Example can I use 7 speed cog set?). Looks like there is approx 130mm between the dropouts. Is this standard? Itís a steel frame so I could bend it out a bit if needed.

thank you!!

5 speed chain ok with 6 speed?

ThermionicScott 05-23-18 02:53 PM

You'll want to get a new chain no matter what. Any chain marked 6/7/8 speed will do.

Ghrumpy 05-23-18 03:30 PM


Originally Posted by unclejemima (Post 20356360)
My sons bike has a crappy old 5 speed falcon rear derailleur and grip shift. The bike has 20Ē wheels.

The derailleur is a pos from day one and has never worked good, and Iíve adjust it for hours and itís just a poor quality part. (And old)


A 6-speed setup is not necessarily better quality than a 5-speed. It just goes to 6. Quality is a matter entirely unrelated to how many cogs it has.


Originally Posted by unclejemima (Post 20356360)
My other son has a 6 speed shimano unit on his bike and it works great. I want to get something like that to replace the 5 speed on my other sons bike so his shifts and works nice as well.

The shift quality may have as much to do with the shifter as the derailleur. It has nothing directly to do with how many clicks it has.

See where I'm going with this?


Originally Posted by unclejemima (Post 20356360)
my question is how and what do I order for a derailleur, cog set, shifter and chain? Iíve heard a 5-6 speed cog set are identical width and should interchange just fine, but can I use a shimano derailleur with say a sram grip shift?

Certain SRAM shifters work with standard spacing and Shimano derailleurs. The gaps between the cogs are the same for 5s and 6s standard freewheels. But some shifters have more clicks.
A 6s freewheel is wider than a 5s of course, so you will probably have to respace the rear axle to accommodate the wider freewheel. Then you will have to re-center the rim.

Originally Posted by unclejemima (Post 20356360)
at what point do the cog sets get to wide to work on a smaller kids bike? (Example can I use 7 speed cog set?). Looks like there is approx 130mm between the dropouts. Is this standard? Itís a steel frame so I could bend it out a bit if needed.

Not needed. 130mm will certainly accept a 7s freewheel. But you would have to respace the rear axle even more because the 7s freewheel is wider still than the 6s.

So, yes, 130mm will accept anything from 7s to 11s rear hubs, but they would be kind of a silly indulgence on such a bike.

Originally Posted by unclejemima (Post 20356360)
5 speed chain ok with 6 speed?

Depends on the cogset. Flat cogs, no problem. Cogs that have Hyperglide-style ramps will not work with a standard 5s chain if the chain pins protrude from the side of the plates.

Allow me to suggest you replace the derailleur first, before attempting to change to a 6-speed setup. Might save you a lot of unnecessary work.

unclejemima 05-24-18 12:11 AM

Thanks for the replies :)

sorry did not mean that 5 speed was worse or better than 6 speed only that I though 5 speed was old school and Iíve not seen it used much now-a-days.

ive tried replacing the shifter as well with a quality sram unit and no luck.

knowing what sram shifters will work and what donít is what Iím not sure. How do I know? Something to do with ratio???

respacing the rear wheel is something I never thought of, not have I had to do that before so better to leave it alone. Just curious is it difficult to do?

Iím going to try and find a new 5 speed derailleur, cog set (as Iíd imagine the hyperglide style is newer and easier to move between gears) as well as a new chain. This cogset is old anyhow and looks abit warm.

thanks for the info!!


Bill Kapaun 05-24-18 12:18 AM

When I flipped bikes, I wouldn't touch anything with a Falcon on it.
They were typically low end (overweight) bikes with the cheapest wheels & drive train.
I never got a Falcon to shift/index well. Maybe with a friction shifter?

You might just want to look at a better used bike.

Kontact 05-24-18 02:05 AM

There are all sorts of potential problems with this conversion that could turn this project into a money pit. How about a used bike off CL as an upgrade? You might be able to buy something decent for the money you would have spent on freewheel, chain, derailleur, shifter and cables.

fietsbob 05-24-18 07:57 AM

6 speed is certainly wider than 5 .. Frame has ro be spread wider to get a wheel with that now wider axle in..


Why not just get a nicer quality 5 speed freewheel .. Sun Race , IRD.. Shimano-Singapore..


I suspect the (unstated) bike selling price was low, allowed by a parts pick with cost as the most important criteria..



..

unclejemima 05-24-18 08:27 AM

Itís a bit of a story...the pedal bike looks like a dirt bike and the kids love it. Itís a Kawasaki stickered bike, with front and rear suspension, steel frame, heavy...but to a kid whoís 7, itís the coolest thing in the world. I could buy him a carbon s-works bike and he would rather have the kawi bike. Ah to be a kid again ;)

the falcon will not index correctly, yes. This is the main problem.

im going to try and keep it cheap as possible donít worry :). Thatís why Iíd hate to be a bike mechanic who gets paid to fix Walmart bikes. ďHey man it cost more to get a new chain installed than I paid for the bikeĒ mentality. This is why I do my own wrenching and I enjoy it :)

Is it true a derailur is the same (within reason) so that I can have a low end shimano derailur that can index for 5, 6, 7 speed just needs a different shifter on the bars?

fietsbob 05-24-18 08:30 AM

Wall mart does not fix them, if returned, they dumpster them..

they may not even have anyone, there, to even put them together right, in the 1st place..

Retro Grouch 05-24-18 10:08 AM

What do you mean by crappy shifting?

Everything on a bicycle works together. Even low end Shimano Tourney equipped bikes can be made to index reliably. The trick is that everything: shifter, derailleur, freewheel, chain and even cable housings all have to match. That's a lot of stuff to have to buy to fix up an old crappy 5-speed bike.

unclejemima 05-24-18 11:19 AM

Sorry I meant that bringing a Walmart bike to a pro bike shop will cost more to fix than the bike is worth.

ive relaxed the shifter cable and all the housing with new. Iíve also tried to replace the shifter with a sram unit and spent an hour trying to get it to index correctly. As the previous poster suggested the falcon units are not unheard of to index correctly. So Iíve tried the simple (cheap) stuff.

Iíve actually got an old shimano xt unit (9 speed) floating around that I might have a go with but could I use a derailleur that was 9 speed with index shifters (index shifter is long gone) with a 5 speed and grip shift??

so those worried about cost fear not! The xt derailleur I have is free and has been sitting in a box for years :)

Phamilton 05-24-18 12:24 PM

Time to teach the kids how to friction shift, then almost any rear derailer will do. All my geared bikes as a kid were friction shift, they'll do fine. They won't gain anything tangible from adding a cog, moving from 5 to 6 speed the top and bottom will probably stay the same and there will be one more in-between gear. Put the xt on and a cheap thumb shifter, viola. Better yet, have them help you do it, then they learn mechanical skills, shifting skills, and their beloved bike is back in action.

Mickey2 05-24-18 03:38 PM

Some of the old 5 speeds were rather good, I promise. I haven't seen them new since the mid 1980s though, but vintage bikes turn up now and then. They weren't indexed like later shifters, you developed a feel for them and it was all fine. Some had a sort of very fine indexing, just tiny clicks in the shifter when you moved it. but no numbers or indications which gear it was. Some were better than others. I think I had a Simplex on a Peugot, it might have been Hurret, I can't remember anymore, It had 5 speed cassette in the rear and two cogs in front. The trick was to keep everything clean and well oiled from shifter to derailleur. The cogs were much thicker on these and lasted noticeably longer than what we get today.

Either way, better gears can probably be found, and you might even find a 3 or 7 speed gear hub that will work with the frame.


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