The CM-25 is a fantastic chain cleaner, that will probably outlast your next two bikes and would be an asset to any shop or pro wrench. The only thing holding it back from a higher score is the price
Buy if, You're cleaning lots of chains or never want to buy another chain scrubber
Pros: Solid construction, replaceable parts, does exactly what it's supposed to
Chain scrubbers are not a new innovation, and there are some really good ones out there, including Park Tool’s own Cyclone, Pedro’s Pig and Finish Line’s Shop Quality Chain Cleaner.
There are some cheapies that get the job done too, but make a huge mess in the process. The vast majority are made from plastic, which keeps them cheap, and for some the guts can be changed when they begin to wear out.
Last year, however, Park Tool introduced the CM-25 Professional chain scrubber — essentially a shop quality version of the brand’s CM-5.2 Cyclone scrubber.
Made from die cast aluminium, this new chain cleaner is designed to stand up to some abuse, and essentially every part is replaceable, including the brushes and sponges, which are housed in convenient trays for fast swaps.
The case is made from die cast aluminium, which provides for the majority of its nearly 500g weightColin Levitch / Immediate Media
Other than the obvious metal exterior, this CM-25 also sees an upgraded cleaning system. There’s an additional sponge and two felt wipers, which not only give all four sides of the chain a healthy scrub, but also help to keep the degreaser inside the scrubber.
Drips are always a problem with just about every other scrubber I’ve used before. Usually, as you run the chain through the scrubber, a good bit of degreaser drips out the end, or splashes out if something seizes on the inside and jerks the whole unit — if you’re working in your garage or the back of a shop, you probably don’t want dirty degreasers dripping on the floor.
The additional sponges and wipers do a good job on the CM-25 of soaking up all the excess liquid as the chain leaves the housing, and I’m yet to experience any jerk and spill.
The latch is as sturdy as the rest of the unit and provides a satisfying pop when engagedColin Levitch / Immediate Media
Speaking of the sponges and wipers, they’re not actually connected to the trays they sit in, meaning they can be removed and individually cleaned should they need it.
The problem here is that they’re not connected, and the first time I used the CM-25 my chain spat both sponges and wipers out of the cleaner like sour milk. They are easily replaced and with a bit of deliberate tucking of corners I’ve not had the problem since.
The new scrubber system works well too, and your chain comes out sparkling clean. I’ve run some pretty nasty mud and grease encrusted chains through and with a few revolutions of the crank they look almost brand new. Whether or not it cleans any better than Park Tools’ own Cyclone, or similar offerings from other brands, is hard to say.
The RBS-25 Replacement Brush Cartridge, which the scrubbers and sponges are mounted to, is easily replaceable and pops in and out of the cleaner. A new set will cost you $18.95 / AU$39.99.
The guts of the CM-25 consists of three brushes, two sponges and two felt wipersColin Levitch / Immediate Media
Like most chain cleaners, there is a hole in the lid so that the unit can be put on the chain and the reservoir filled once everything is lined up. However, because the unit has a metal casing you’re unable to see how much liquid is in there, so I found it much easier to pour degreaser in the reservoir first and then close it on the chain.
So overall, the new CM-25 is a fantastic chain cleaner and will probably outlast your current bike, and the next two after that, but the burning question is, is it worth the money? This is a question I have struggled with for some time.
The internals are completely replaceable and are housed in easy to remove traysColin Levitch / Immediate Media
When you factor in that CM-25 costs £79.99 / $98.95 / AU$189.99, the RBS-25 Replacement Brush Cartridges cost £7.99 / $18.95 / AU$39.99 and a Replacement Brush set costs £10 / $10.49 / AU$TBC it’s a tough sell, especially as Park’s own Cyclone costs just £27.99 / $26.49 / AU$54.99.
Cheaper plastic chain cleaners still last a fair while before they or their interior parts need to be replaced, too.
To be frank, for shops and pro mechanics that are cleaning dozens of chains a day I think the CM-25 will be a big hit because of the quick change internals and bombproof build quality, and might even appeal to the home mechanics who love tools. But for everyday riders who might clean their chain a few times a week, the price tag will likely prove too heavy.