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Hi all, bit of a basic question for many I'm sure, but I'm in need of a wee explanation please. On occasion someone in the house loses a bolt on their bike. I keep old and unused bolts, but appear to have run out and am looking to buy a selection to have when needed. So, basically what do I need?
Q1 What does M5 for example mean?
Q2 What thread do they have?
Q3 What is their diameter?
and any other useful information +/- links greatfully received.
This is quite useful -
[url= http://www.ebay.co.uk/gds/Your-Guide-to-Metric-Bolt-Sizes-/10000000178761277/g.html ]Your Guide to Metric Bolt Sizes[/url]
Thanks Pinkster, but I am still unclear what type are commonly used on bicycles. Perhaps I'm being a bit slow ?!
Apart from pedal and BB threads, bikes use standard ISO/Metric threads of standard pitch. M4 = 4mm, M5 = 5mm etc. Standard sizes for bikes are M4, M5 and M6. The likes of bottle cages, rack mounts, disc brake hub, stem face plate are typically 5mm. Headset topcap, brake disc caliper mount and seat collar are often 6mm
Thanks again, I think I'm getting it now. M4 (for example) requiring a 4mm Allen key I guess?
Amazon as good as anywhere else?
I get all my bolts off bolt base on eBay. Based in Scotland and always had what I needed for my bikes.
I think I'm getting it now. M4 (for example) requiring a 4mm Allen key I guess?
No, that would be too useful!
The number is the (approx) diameter in mm's.
Thanks everyone, I think I have it now. Bolt base seem to have just what I'm looking for.
Usually size down for the allen key.
M4 = 3mm allen key etc.
Usually size down for the allen key.
But depends on type, eg, cap head or button head (button head are smaller).
Bound to be a local fasteners place. Mine does SS bolts at a fraction of a cycle shops price.
Screwfix do a good range of Allen keyed bolts and nuts, they have stainless ones too
If you are unsure about correct sizing of bolts then you may find [url= https://www.pro-bolt.com/pro-gauge-bolt-measuring-tool-essential-item-for-tool-box-5.html ]this pro-bolt measuring gauge handy[/url]
Screwfix is a great shout thanks, as there's one local and they've always been very helpful in the past.