Downtube shifter bolt broken

rolf_f

Set off on my nice 70 miler today on the old Dawes. Got less than one mile and 'ping' off comes the left side downtube shifter lever. After searching to find the bits that had come off, I hurried home, changed bikes, did the run and have now got back. To reality. And one broken Dawes

Anyway, I potentially have a source for a replacement lever but the question is - how easy is it to extract the broken bolt end. I don't think I'll have a go myself as I don't want to end up making a mess of a nice bike so I'll probably bob it over to Spa Cycles this week. But I would like to know that it is a straightforward job

Presumably just a case of carefully drilling the bolt stub out?

Also, is there likely to be any issue over braze on mounts? The lever is Sachs Huret from 1990 and I'd like to get similar to replace it.

Thanks in anticipation!

(Edit: at least it had the decency to brake near home - being stuck on a single ring on todays route would have been tedious!)

sungod

if the thead goes all the way through and out the other side then you can drill a hole in the end of the snapped bolt and screw another, smaller, bolt into it to drive it out

otherwise drill a hole in the end and use a screw extractor, like...

http://www.google.co.uk/products/catalo ... ps-sellers

it's straightfoward to do, although with small bolts it needs care to drill the hole without damaging the surroundings, use a new bit and go easy

a dremel or something similar would be ideal i reckon, but i've done it with a normal powerdrill on an m5 stem bolt, was ok

if there's a chance the old bolt is gundged up, put some acf-50 or penetrating oil on it and leave for a day before trying to get it out

rolf_f

Thanks for that. I'll see how much Spa will charge and then decide if I have a go! I have a feeling that the bolt hole isn't blind (I'll get the other side out and check in a bit). It certainly won't be bunged up - I only just refitted it in January but presumably overtightened it (though the fracture looks a bit crystalline...). Am wondering if I can just get a replacement bolt...........