Titanium bolts question

[MOBB]

I fancied upgrading my bottle cage bolts etc to fancy ones

Bought some from TI Parts and very happy with them

However my gravel bike has loads of bolts all over it for bags, mudguards etc and I assumed they would be the same bolt thread, but they appear to be very slightly different to bottle cage bolts, look almost identical but wont turn as soon as you try

Any pointers to what I might need instead of bottle cage bolts?

[SlimJim16v]

https://www.amazon.co.uk/Stainless-Thread-Imperial...

[Rough101]

Assuming it’s also 5mm, the thread pitch should be the same, M5/0.8.

You sure they aren’t M4?

[MOBB]

Just checked and the bolts I bought are M5x12

They fit the bottle cage recesses fine, but are too tight for the frame ones

[oddball1313]

M5 is right ahole as there’s two different pitches in common use (0.8 & 0.5). it’s possible they are imperial as well 3/16 is quite close

[hidetheelephants]

MOBB said:

Just checked and the bolts I bought are M5x12

They fit the bottle cage recesses fine, but are too tight for the frame ones

Hold the threaded part of the new bolts against those of the existing frame bolts; do they match? Holding them up to a light source will help. If not you'll need to identify what the frame bolt thread is.