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What would you put in this hole to stop the frame filling up with detritus?
So far my muddled brain has come up with Caulk or mastic.
You can buy blanking bolts. On the phone so not good at copying links, but they'll be a neat solution
Well greased ,cut off bolt ?
Bit of silicon would do the job. Or these: http://clee-cycles.co.uk/esite/P17902/product
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is an internal 9mm a 10mm bolt?
eBay has loads of cheap blanking bolts or google for some bling!
have you got any old canti-studs ?
they'll fit just fine, I should think
MPart do cheap ones.
Tapered foam ear plugs weigh nothing and seal it perfectly.
I have some unused xlite red blanking bolts you can have for the price of postage! I bought them but changed to a disk only frame so never ended up using them.
Andysredmini at hotmail dot com
[url= http://www.transitioncycles.co.uk/productdetails.asp?productid=05441 ]Little blankers[/url]
YGM Andy.
Rubber plugs, stainless steel grub screws, fancy bolts as above, circle of helitape (as used in F1 to cover holes in bodywork over things like nose cone attachment bolts or wing adjustment bolts to keep them aerodynamic).