Uh OH! Hole in Chainstay (93/94 Dave Yates Diabolo)

I'd clean up, ensure there's no further damage and wrap some carbon fibre around it. But I have the cf tow & laminating epoxy readily available + some skill to use it.
Cf means you don't need to respray the frame, and it will reinforce the rest of the [potentially rusty] stay.

You're saying it's only intended for light trail riding, in which case you should be fine. Even a crack in that area will not necessarily result in a critical failure - you'll probably notice it before you crash, and be able to get home + your teeth are reasonably safe.

PS It's probably safe to ride as is, but at the end of the day it's your teeth we're talking about - not mine 😆

PPS If you're really uncomfortable riding a bike like that, send it to me. ;)
 
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Definitely brazing silver solder, not electrical stuff (mostly lead/tin/silver/copper alloys), or the higher silver content solders used in jewellery. Neither of these have sufficient strength for the job.

Brazing silver solder commonly varies from 39 to 55% silver, the remainder being copper and zinc. Higher silver content helps the filler flow, but is not really worth the expense here, it's mainly for lug work. They are made to international standard formulations, referred to as Ag40, Ag49, Ag55 etc. Make sure it's cadmium-free, too...Older alloys included cadmium to help flow, but it's very nasty stuff, so generally avoided these days if at all possible.

Temperatures needed for range from 6-700°C, so possible with propane and some patience. For small work like this, 1mm or 0.75mm filler is good, and is available for less than £10 for a 50cm rod of Ag40.
You'll also need a compatible flux, which will probably be the biggest expense (£20-30) since it usually comes in nothing smaller than 1Lb tubs. I've not seen silver solder flux coated or flux cored anywhere.

Also...to add a little confusion, make sure you avoid what the Americans often call 'Nickel Silver' rods. This is a high temperature (950°C), high strength brazing rod that has no silver in it at all, but more nickel than standard silicon bronze brazing rods, so has a similar silvery colour.

All the best,
Thanks Dan. Seems like a lot more work than its worth. If I repair it I think I'll find a local welder who can sort it out for me.
 
Thanks for this - I was looking for Toby's Cycle Works and my search didn't bring him up. Looking at the prices of those other builders I don't think I could afford them any more than Dekerf. Nice bikes though.

I really appreciate what a good deal my Elephant NFE was now - and Marino in Peru.
 
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