ChainKASE 7' Ebike Chain Lock – 8mm Hardened Steel, Combination

Seven feet of 8mm hardened steel, and a combination instead of a key. That makes this the outlier in our lock lineup, and it is worth being upfront about who it is for: this is the lock you buy when you need to reach around something big, or lock more than one bike at a time, and you would rather not keep track of a key.

• 7-foot chain built from 8mm hardened steel links
• Resettable 4-dial combination with 10,000 possible codes — set your own, no keys to carry or lose
• Steel ball click gear mechanism in the lock body
• Nylon chain sleeve resists water and heat and keeps the chain off your paint
• Weight: not published by BiKASE. Seven feet of 8mm chain is genuinely heavy — expect this to be the heaviest lock we sell, by a wide margin.

Which lock do you actually need?

This is the fifth lock in our lineup and the most specialized of the group. Here is how we would pick between them, and our ebike lock buying guide compares them side by side.

• Buy this one for length, not for security tier. Seven feet is roughly two bike lengths. That is what lets you chain two or three bikes together at a trailhead, wrap a fat post or a picnic shelter upright, or run through both wheels and the frame in one pass. If you only ever lock one bike to a normal rack, the 4-foot ChainKASE X-TREME does that job in less chain for $20 less.
• Combination is a convenience trade, and we are not going to pretend otherwise. No key to lose, none to leave at home, and easy to share with a partner or a kid. But a 4-dial combination is a different kind of mechanism than the Z-Key BumpBlok cylinder in our UKASE MAX and ChainKASE X-TREME, which is built specifically to resist picking, pulling, and drilling. If your concern is a determined thief rather than a lost key, buy keyed.
• It does not live on your bike. No frame bracket, no case, no bottle bosses to worry about. Seven feet of chain goes in a pannier, a rack bag, or over your shoulder, and you will feel it either way. If you want reach you can actually carry, the folding Link Lock opens to 34" at 2 lbs.
• No published security rating. BiKASE does not publish a Sold Secure or ART rating for this lock, so we are not going to invent a tier for it. Judge it on the construction listed above and on how you actually plan to use it.

7-foot combination chain lock FAQ

Why would I want 7 feet instead of 4?

It comes down to what you are locking to, or how many bikes you are locking. Four feet handles one bike and a normal rack. Seven feet handles two or three bikes chained together, oversized posts, trailer hitches, and the awkward trailhead structures a shorter chain will not reach around.

Can I lock two ebikes with it?

Yes, and that is the strongest reason to pick this over the 4-foot version. Run it through both frames and the rack. Just remember the flip side: one lock securing two bikes means one cut loses you both.

Is a combination lock less secure than a key lock?

Generally, a well-made keyed cylinder is the harder target, and BiKASE's own keyed locks use a cylinder built specifically to resist picking and drilling. The combination buys you convenience instead. That said, on a chain lock the bigger question is the chain: an attacker still has to get through 8mm of hardened steel, and that takes real tools either way.

Can I set my own code?

Yes. The combination is resettable, with 10,000 possible codes across the four dials. Change it off the factory setting before you trust the lock with anything.

How much does it weigh?

BiKASE does not publish a weight for this lock, so we are not going to make one up. What we can tell you is that seven feet of 8mm chain plus a lock body is the heaviest thing in our lock lineup. Plan on carrying it in a bag rather than on the bike.

Will it fit in a pannier or rack bag?

Coiled, yes, in most full-size panniers and rack bags. It will take up most of that bag and add real weight to one side, though. If you ride with it regularly, a rear rack bag centered over the rack is more comfortable than one loaded pannier.

Will the chain scratch my frame?

The nylon sleeve is there specifically to prevent that, and it also sheds water and resists heat. It is still worth being deliberate about where you drape the chain while you thread the lock.

Is one lock enough for an ebike?

For short, attended stops, usually. For overnight parking or anywhere bikes actually get stolen, two locks of different types is the honest answer, because it forces a thief to carry two different tools. This chain pairs well with the UKASE MAX U-lock for exactly that reason.

Comparing locks? See the 4-foot ChainKASE X-TREME, the UKASE MAX U-lock, the UKASE MAX with cable, or the folding Link Lock. Still deciding? Start with the ebike lock buying guide.