Half Link Chain?

[NATURAL ANKLING]

Hi,
The reason for a half link chain

[SimonCelsa]

They may come in handy if running a single speed bike with relatively short horizontal dropouts.

If required to shorten or lengthen a 'normal' chain then each link removed can result in the wheel shifting too far to safely be secured in the dropouts. A half link chain obviously gives less of a shift when removing links.

Probably not explained so well but that is the gist of it I believe. I have never used one but do possess a couple of 'half links' for this purpose,

All the best, Simon

[foxyrider]

BMX'ers use them as they are much tougher than a 'normal' chain. You can only use them on single speed set ups, they lack the sideways flex required for multi sprocket set ups.

[Gattonero]

BMX'ers use them as they are much tougher than a 'normal' chain. You can only use them on single speed set ups, they lack the sideways flex required for multi sprocket set ups.

The main reason for BMX is that an 1/2 link chain does allow the use of small cogs, like 9t drivers used on modern quality BMX hubs.
On normal setups there's no real need for the 1/2link chain, one can add a single 1/2 link to a normal chain when the combination of chainring+sprocket+dropouts does not allow for a decent chain tension.

[KM2]

I married a normal chain with few half links to run an hub gear on vertical dropouts. Fiddly but works.

[Gattonero]

I married a normal chain with few half links to run an hub gear on vertical dropouts. Fiddly but works.

The chain will get slack with the time, on hub gear you can be ok but not on a single-speed and on a fixed sprocket the slack becomes annoying

[NATURAL ANKLING]

Hi,
Isn't it all to do with even elongation on every link, not so on a standard chain?

I always thought that the bent plates could straighten on a half link, but I imagine that manufactures would of thought of that.........

[ukdodger]

Hi,
The reason for a half link chain

The main reason I think is to accommodate bikes with vertical (and therefore can make no allowance for chain stretch) dropouts. I've had to use one half link in a normal chain on every hubgear I've ever used. You just cant get the right chain tension by removing or inserting two normal links.

[Brucey]

Individual half-links are used for chain adjustment purposes.

Chains made entirely of half-links of course also allow this adjustment, but that is not the primary reason for their use.

Nor is it anything to do with 9T sprockets, not really. Most half-link chains have very deep side plates and I have seen some small sprockets where the chain stands off on the base circle if the side plates are too deep, and some half-link chains cannot be used.

No, the real reason for such chains on BMX bikes is to allow easier 'grinding'. You can tell this is the case because nearly all such chains have asymmetric side plates so that the 'outside' of the chain presents a smooth and flat surface.

Also, the chain should be fitted so that when pedalling, the open end of each half link is facing forwards. The means that the lower run presents the narrower (inner) end of each link to obstacles 'being ground' first and this means that the side plates are less likely to catch on something and then pop open. If a normal chain is used or a half-link chain is fitted facing the other way, the side plates are at a greater risk of snagging and the chain popping open.

cheers

[NATURAL ANKLING]

Hi,
So the fact that every link has even stretch and wear unlike normal chain (even as in- every link has one fixed pin and one hole for the adjacent link pin) has nothing to do with it and is not a considering factor?

[Brucey]

not that I have heard.

In point of fact 'other users' i.e. who don't 'grind' (eg fixed gear types) usually report that half-link chains don't last that long. Probably the bushings are not well made or something, although it could be that every link appears to go out because the joggle in every side plate just straightens slightly if the chain sees a high tension load.

cheers

[NATURAL ANKLING]

Hi,
I've never used half link chains before so I don't really know, the forum type info on the net seems inconclusive.
I have only used a half link once to correct axle position when using a different front sprocket on a motorcycle.
Don't hear much from users here so I guess there is not much to be gained.

[Gattonero]

Individual half-links are used for chain adjustment purposes.

Chains made entirely of half-links of course also allow this adjustment, but that is not the primary reason for their use.

Nor is it anything to do with 9T sprockets, not really. Most half-link chains have very deep side plates and I have seen some small sprockets where the chain stands off on the base circle if the side plates are too deep, and some half-link chains cannot be used.

No, the real reason for such chains on BMX bikes is to allow easier 'grinding'. You can tell this is the case because nearly all such chains have asymmetric side plates so that the 'outside' of the chain presents a smooth and flat surface.

Also, the chain should be fitted so that when pedalling, the open end of each half link is facing forwards. The means that the lower run presents the narrower (inner) end of each link to obstacles 'being ground' first and this means that the side plates are less likely to catch on something and then pop open. If a normal chain is used or a half-link chain is fitted facing the other way, the side plates are at a greater risk of snagging and the chain popping open.

cheers

Not many people do grind on the chain, unless it happened by mistake. I don't know anyone that does bother using a standard 1/2" link chain on small drivers (you can get 8t). The dudes just buy the 1/2 link type 'cause they know it works, and are happy with that