louky

I needed to break a chain on a bike I am converting to electric. The chain is supposed to be a KMC Z7 according to the specs. I looked for a quick link but all I noted was that one of the pins was black. I pushed this out to break the chain but unfortunately pushed it all the way out. There is a good chance that this chain will need to be shortened a few links with the conversion. Does this chain reattach with a typical "magic link"? If I do have to take some links out, should I just try to reattach by driving the pin back in with the chain tool? What's up with the one black pin anyway? Thanks in advance!

alcjphil

Is the chain really a KMC? Don't rely on the specs, look at the chain. KMC chains usually have the company name engraved on the chain links and they are sold with the quick link included.

louky

I will look at it. The chain is coming off a new Trek Verve 2 that I bought in the fall. It is not a replacement chain.

alcjphil

Manufacturers often will substitute components from other companies due to supply shortages. That different chain pin sounds very much like the joining pin used by Shimano to install their chains

louky

I just looked at the chain closely. It is stamped KMC. It also has "narrow" stamped on the links. Do I have to get a special quick link for this? Is there a specific direction the chain needs to be when I reinstall?

grumpus

Chain is usually directionless, rarely they will have asymmetrical side plates in which case note which way they go before removal. You'll need a quick link to suit the width of the chain - they're pretty generic, so you'll only need to know if it's 6-7-8-speed, 9-speed or 10-speed to order the right part. Beware "bargains" - there are some very cheap and nasty quick links being sold as branded items.

FBinNY 

You always have the option to use a connecting link of the right width. Just cut the chain ending with inner links at each end. Or, if you don't shift aggressively can get by usinf the chain tool in the conventional way pushing one pin out but leaving it in the opposite plate to be pushed back in. I suspect that was the intent of the black pin, but you overshot, and can't go back.

veganbikes

Just FYI they make the Verve 2 electric, it is an expensive bike for what you get and you would be better served on the cheaper but slightly better spec'd Gazelle Medeo T9 but it already exists and would be a more reliable option as they both use Bosch which has good support behind it.

fooferdoggie 

my trek e bike has a kmc chain. that seems typical of e bikes.

louky

I am familiar with the Verve 2 electric. My GF was needing some help on hills and ended up getting one. She liked it OK. I rode hers and decided I would do electric also. I researched and decided my best path was to retrofit a Bafang BBS02 to my 20 year old Trek MB. When I got mine finished, I talked her into riding it. The difference between her "store bought" Verve and my retrofit was so pronounced that she decided that she wanted a larger motor. We shopped for a used step through Verve and bought the Bafang kit for it. She loves the huge increase in power and the hand throttle. She will sell the factory electric bike in the spring. I purchased the Verve 2 to move my electric kit on to. I am 74 and can use the low step through feature. I was also wanting the larger wheels and the disc brakes will be a plus. I agree the Bosch system is better engineered and better supported, but the lack of power would make it hard to go back.

Hondo6

If you've ridden the bike a fair amount since you bought it, you might want to use a new chain. You can keep your current one as an emergency spare if you do, provided you check it for excessive wear and it checks out OK on that score.

Chains are wear items ("consumables"). But if they're allowed to wear too much they start to wear cassettes/freewheels and chainrings rapidly, leading to premature wear-out of those items too. And I understand eBikes tend to be harder on chains than regular bikes.

Further: 6-7-8 speed chains are also cheap compared to cassettes, freewheels, or chainrings. I've seen SRAM 830s (a good, basic 6-7-8 speed chain) for approx $10-12 recently.

Edited to add: to answer your original question, pretty much any 6-7-8 speed quick link should work for your existing chain. KMC quick links of that speed range tend to be re-usable (check the package to be sure; some KMC quick links aren't specified to be re-usable) and are of good quality; ditto for SRAM's. (I'd recommend using 1 link with a chain, then discarding it with the chain or at most keeping it as an emergency spare. Though good, they do wear and don't last forever.) They're typically available in 2- and 4-packs at a fairly reasonable price. It's worth taking an extra one with you while you ride IMO in case you have a chain failure while "out and about". That could be the difference between walking and riding home.

merlin3008

You would need a quick link of matching width for the chain. FYI, if you pushed out a black pin that looked different than others, my instinct would be to move that link when shortening.

louky

I got this put together today and went for a 10 mile ride. I had a cheap link that I installed as I am waiting for the KMC links. I had to remove 2 full links from the chain due to having a smaller gear on the front with the Bafang. Thanks for all the advice! Picture to follow.