GT85 Bike Silicone Shine is claimed to provide 'an all-over showroom shine and glossy finish to your bike'. Obviously a no-no for matt and satin finishes, it's reputedly kind to rubber, reduces friction, and translates well to rubberised/suspension components.
Credit where it's due, it does a decent enough job but, speed aside, polymer waxes achieve longer-lasting effects and, for most jobs, good quality furniture polishes will achieve very similar bang for considerably less buck.
Exact composition is a trade secret but it seems to be a blend of solvents and silicone polymers. The solvents gobble surface dirt on contact and then evaporate, leaving only a gleaming bike behind. It's literally blow 'n' go, too – at least on bikes sporting a little filmy road spatter. Workhorses and mucky cross/mountain bikes demand a good bucket wash and dry first.
Shake the silicone spray vigorously for 30 seconds or so and then apply in short bursts from 25-30cm. In close proximity to disc brake rotors, saddles, handlebar coverings and other situations where overspray spells trouble, squirt into a lint-free rag/micro-fibre cloth, then apply. Although buffing afterwards is unnecessary and does dull the sheen very slightly, it has prevented dirt sticking as readily in the longer term.
Overall effects are really sharp, especially on metallic enamels, carbon fibre, black anodising and electroplate. It has transformed weathered lighting brackets, computer mounts and chrome-plastics too. GT85 reckons it lubricates and protects rubberised components such as suspension/seals without doing anything unkind, and in a pinch, light dustings will keep control cables slick.
It's less sticky than some bike-specific, silicone-based formulas I've used, and machines entering season-specific storage sport precious little dust several weeks later. Following a few wet rides, my Holdsworth's rear triangle, chainstays and bottom bracket shell all wore some residual spatter, but this was dismissed in seconds with a clean rag.
Durability depends on the context but is broadly on par with other bike-specific formulas I've tested over similar timescales. One light coat has lasted several weeks on most of my fleet, exposed to a mixture of sun and showers. Light dirt is easily shifted without stripping the protective layer, although bikes in daily service have required fortnightly applications.
Several weeks' neglect saw my rough stuff tourer cum workhorse cultivating a deeper layer of grime, though still less than WD40 and similar water displacers in comparable contexts. It also kept a stone chip or two from succumbing to the dreaded orange taint. Two squirts applied via clean kitchen towel restored the showroom sheen.
Convenience is the main draw here: if you're short on time and/or didn't like polishing, it's one for the toolbox. That said, so long as you minimise contact with rubberised/plastic regions, good quality beeswax furniture polish achieves similar results and is considerably cheaper.
Convenient, relatively long lasting and on par with other silicone-based formulas
road.cc test report
Make and model: GT85 Bike Silicone Shine
Size tested: 400ml
Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
GT85 says: "Provides an all-over showroom sheen and glossy finish to your bike. It's fast acting and dries quickly without the need for polishing.
PRODUCT FEATURES & BENEFITS *Triple acting - cleans, freshens and shines *Helps restore colour and shine *Reduces friction, ideal for suspension parts etc. *Helps prevent cracking/premature ageing of rubbers *Characteristic GT85 fragrance *Fast acting, virtually instantaneous evaporation *Silicone film acts as a release agent to make future cleaning easier
RECOMMENDED USES Paintwork Metal Rubber Plastic Parts".
Useful do-all preserve.
Tell us some more about the technical aspects of the product?
Physical Properties Appearance: A colourless liquid with a characteristic GT85 odour. pH: Not applicable Specific Gravity: 0.788 – 0.808 Viscosity: Thin liquid Flammability, as supplied: Extremely flammable, flash point below -20oC Composition Data, as supplied: A solution of silicone fluids and synthetic fragrance in hydrocarbon solvents and butane/propane/isobutene based propellant. Service temperature: Designed for use at ambient temperatures. Simple to use and requires minimal time to apply, simply spray"
Certainly on par with other bike-specific formulas.
Quite long-lived and attracts less dirt than some bike-specific competitors.
Competitive alongside similar bike specific products, but pricey compared with furniture polishes.
Tell us how the product performed overall when used for its designed purpose
Overall, it achieves a really deep gloss on all surfaces and does a decent job of restoring tired/faded anodising, plastic surfaces, nourishing them too. Cleanliness in the longer term is better than several competitors I've used in the past. However, good quality furniture polishes achieve similar results with marginally more effort and cost around £2 for 500ml.
Tell us what you particularly liked about the product
Very deep protective sheen, no need to buff. Fairly economical when used carefully.
Tell us what you particularly disliked about the product
Nothing specific when considering the design brief.
Did you enjoy using the product? Yes
Would you consider buying the product? Possibly, but not at full RRP.
Would you recommend the product to a friend? Equal to some established brands.
Use this box to explain your score
Versatile polish and a useful workshop staple, but in the everyday sense, furniture polish will achieve similar results on painted, plated and anodised surfaces.
About the tester
I usually ride: Rough stuff tourer based around 4130 Univega mountain bike frameset My best bike is: 1955 Holdsworth Road Path and several others including cross & traditional road
I've been riding for: Over 20 years I ride: Most days I would class myself as: Experienced
I regularly do the following types of riding: cyclo-cross, commuting, touring, fixed/singlespeed, mountain biking
Shaun Audane is a freelance writer/product tester with over twenty-eight years riding experience, the last twelve (120,000 miles) spent putting bikes and kit through their paces for a variety of publications. Previous generations of his family worked at manufacturing's sharp end, thus Shaun can weld, has a sound understanding of frame building practice and a preference for steel or titanium framesets.
Citing Richard Ballantine and an Au pair as his earliest cycling influences, he is presently writing a cycling book with particular focus upon women, families and disabled audiences (Having been a registered care manager and coached children at Herne Hill Velodrome in earlier careers)