Park Tool has made what are arguably the ultimate screwdrivers for bicycle derailleurs, the DSD-2 and DSD-4.
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I wrote about these beauties when I first saw them at Eurobike last year, and now I’ve laid hands on a set to play with.
Why do these even exist?
What if I said you’ve been using the wrong screwdriver for your bikes this entire time? Until Shimano started using hex-head screws on some of its derailleurs relatively recently, you needed a cross-head screwdriver to adjust your high and low limits.
You’d be forgiven for assuming Shimano limit screws have a Phillips head but, in reality, they’ve always been JIS (Japanese Industrial Standard), which require a subtly different screwdriver tip design for the best possible fit.
The subject of standards is a confusing and murky one, as it appears the JIS specification for screwdrivers has been absorbed into the current DIN 5260-ph (DIN is the Deutsches Institut für Normung or German Institute for Standardization). If you’re interested in geeking out on this subject, this article on motorcycle site webBikeWorld is worth a read.
In any case, Park Tool describes the DSD-2 as being “built to exceed JIS standards” and since it’s made specifically with limit screws in mind, you can be confident it’s going to fit.
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The flat blade DSD-4 is meant for limit screws with a full-width slot on the head, like those found on Campagnolo derailleurs.Otherwise, large, flat-bladed screwdrivers don’t have many applications on bikes other than as a general purpose bodge-lever. Yes, I know you do that, we all do.
Beautiful tools are the best tools
If you love tools, Park Tool’s new screwdrivers are delightful. They have a real heft to them, weighing about 50 percent more than the working man’s SD-2 Phillips screwdriver.
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The aluminium handles are pleasingly knurled and have two rubber ring sections for grip. A depression in the end gives you somewhere to rest a finger or thumb when you’re engaged in acts of fine adjustment.Compared to the fat, rubbery handle of the SD-2, the new DSDs are slim and not at all soft. This makes them less suited to acts of vicious torque, but then they’re not really designed for that.
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It should go without saying that the DSD-2 fits Shimano limit screws really well. My trusty SD-2 was always my go-to for limit adjustments, but using it side-by-side with the DSD-2 makes me realise just how poor a fit it is.
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The DSD-2 slots into the screw head like a perfectly square peg into a perfectly square hole. Screw and screwdriver move as one, with none of the wiggling you get using a standard Phillips.
Do I need Park Tool’s new screwdrivers in my life?
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At £30 / $35, Park Tool’s new screwdrivers are a bit of a luxury and the flat blade DSD-4 is hard to justify over more affordable alternatives.
If a better cross-head for derailleurs is what you’re after, you can buy a Vessel 'JIS' screwdriver from Amazon.co.uk / Amazon.com for under £10 / $10.
All the same, the new Park Tool offerings are lovely objects that fit their intended usage perfectly. I’ve long been of the opinion that you’ll never regret buying good-quality tools, and I can’t imagine you’d feel much buyer’s remorse with these in your toolkit.
- Buy the Park Tool DSD-2 now from Amazon.co.uk / Amazon.com
- Buy the Park Tool DSD-4 now from Amazon.co.uk / Amazon.com
Thanks to my former BikeRadar colleague Dave Rome for piquing my interest in niche screwdrivers way back in 2015. If you like tools, I’d recommend following him on Instagram.