Kickstand, either at the rear stays or the BB.....
.... Voids Thorn frame warranty.
This still perplexes me
Hi Pete!
Thorn explain their position here:
http://www.thorncycles.co.uk/FAQ/prop.pdfNothing is infallible: Click-Stands can sink in soft soil and spill the bike, too. One has to survey the surface and then take reasonable preventive measures (can lid, FatFoot, tennis ball) to ensure success in those particular conditions. Just as with a frame-mounted kickstand, it'll work well the majority of time and poorly on occasion. When those occasions appear more likely than not, I lay the bike down or lean it against something instead.
A number of the damaged frames given to me by the friend with the used-bike shop had brazed-on kickstand brackets. Most were fine, but three had been torqued off the frame. My guess is the damage was caused by people balancing atop the bike with the kickstand deployed, way overloading the connection. I know some European makers specifically forbid installing a kickstand to such brazed-on brackets if a touring load is to be supported; the disclaimer is included as part of their (translated) warranty conditions. They think it too likely for failure to occur and want to indemnify themselves against what they see as greater risk. Since in many cases these brackets replace the chainstay bridge, a failure can compromise frame structure. A couple of those damaged examples tore out a small chunk or two of chainstay steel along with the bracket. Ouch.
Here's Rivendell's take on the matter:
http://www.rivbike.com/category-s/335.htmI think rear-mounted kickstands -- those clamped to a bracket that captures the seat- and chainstays on either side of the left-rear dropout, as yours does -- are perhaps the most stable of bike-mounted kickstands and cannot be fouled by a crankarm (backing up a bike in low gear and fouling the BB-mounted kickstand with the left crankarm can cause some real damage at the clamp; someone did that to one of my bikes once). My father is pleased with the rear-mounted stand I installed on his touring bike and no damage has occurred in the many years it has been used unladen. He simply preferred not to use it when the bike was loaded for touring.
Here's one way to look at it: If someone like yourself uses care and respect for the materials and forces involved and has no problems...Thorn won't see a warranty claim and the user will remain happy 'cos the frame won't be damaged. However, they have found kickstands can cause problems in some cases and have decided not to cover any resulting damage under warranty. I really don't think it is just about cost-containment and reducing warranty claims. Thorn have shown every sign of wanting a positive, long-lived experience for owners/users of their bikes and I think they have made this recommendation in good heart based on their experience for the majority of riders and as a result of their experience. They've seen a lot, and not all of it good.
Here's an example from the other side: I saw a kid amusing himself as I walked past McDonald's yesterday; he was having fun balancing between the kickstand and rear wheel with his feet on the pedals, front wheel in the air as he talked on his phone! A lot of stress went on his chainstays through the kickstand clamp. People do dumb or thoughtless things on occasion, and the result is not always the manufacturer's fault.
There's a little different angle in this, too...
When researching rear pannier racks, I came across several instances where Tubus denied coverage in fallovers, claiming such damage was outside the scope of their "no-breakage-in-use" warranty. Just another example of stated limits for warranty coverage.
Sure, loads of bikes have kickstands and nothing bad happens. However, Thorn have decided against kickstands for some specific reasons based on their experience, so warranty coverage is another factor to weigh when deciding on the means to a self-propping bike.
All the best,
Dan. (...who offers no warranty on opinions, expressed or implied)