Current Projects chat and miscellany

I don't fully understand that but does chrome on steel lead to hydrogen embrittlement at high temps?

The hydrogen gets into the steel during the electroplating process. I think the fact that my forks have survived 20 years suggests that they are OK, but in the olden days it was common to recommend against chrome plating 753, and the specification delivered to Rourke was that only the dropouts (front and rear) should be plated.

Some nice bikes these couple of pages. You can tell summer is coming up...

Ahh I see, would 753 be more susceptible to damage being thinner tubing?

I think it's something to do with the microstructure of high strength steels. 753 is the same alloy as 531, but the heat treatment regime is different, leading to a different microstructure which gives it the high strength but also makes it more vulnerable to hydrogen embrittlement. I think typical 531 guages are actually run at a higher proportion of UTS in service, so the thinner walls of 753 don't seem to make it more likely to fail.

is that now your roller bike?

No, my roller bike is a Fort. That one went in the bin when I moved house, so I'm now riding my little brother's copy (see above) and Jordan is riding my dad's bike.

in the bin? was it broken?

No, just couldn't see any use or value* for it at the time and didn't have room to keep it hanging around.

*This was before hipsters got interested, and after it became obsolete as a race bike

"before hipsters" says the man with double aerospokes

That fork look like it have a very low trail, is there a reason for it on a TT bike? or optical illusion?

Do you mean trail? It has little offset because it's scaled down for the 26" front wheel.

"before hipsters" says the man with double aerospokes

Spoks were for racing back then, even Boardman used them. I got one of mine as an ex-demo which had been used by CB from Deeside Cycles, who sponsored him at the time.

I think it's something to do with the microstructure of high strength steels. 753 is the same alloy as 531, but the heat treatment regime is different, leading to a different microstructure which gives it the high strength but also makes it more vulnerable to hydrogen embrittlement. I think typical 531 guages are actually run at a higher proportion of UTS in service, so the thinner walls of 753 don't seem to make it more likely to fail.

Interesting stuff :)

P.s. mccd original hipster, literally rode spoks before they were cool ;)

Ahh I see, would 753 be more susceptible to damage being thinner tubing?

its the polishing process that weakens 753 which is also why it shouldnt be carried out on a 653 rear triangle.

Started putting the Denti together today.... awaiting a bb, bartape, and tyres and it will be done...

bad pic...

Spoks were for racing back then, even Boardman used them. I got one of mine as an ex-demo which had been used by CB from Deeside Cycles, who sponsored him at the time.

mccd original hipster, literally rode spoks before they were cool ;)

Well it looks like I was making money off hipsters before it was cool, double win

bad pic...

but GOOD bike, nice paint on that one!

Went down to Sigma Sport and finally found a solution to my Pinarello seapost clamp problem....

....and then found out i have a fork problem. The frame didn't come with the original forks, which would have had the crown race moulded into them. So now I need to track down some Pinarello forks. Sigma suggested looking online and did give me the name of Pina distibutor, so i've sent them an email, but so far haven't had any luck on the internet.

Beginning to realise why the frame was so cheap....

Firstly, I got Ted to hit my bike with a hammer again so now the crank really doesn't hit the chain stay YAY!

This is the new Clearance, still runs close but no more ting, ting, ting, round R Park which is nice.

Secondly Lee Cooper sent me one of his new head badges and a set of decals

So with: and

I did this:

Please ignore tape its only there while the glue dries.

Then I did this:

The frame didn't come with the original forks, which would have had the crown race moulded into them. So now I need to track down some Pinarello forks

There's nothing special about moulded-in crown races - it's just a chamfer at the relevant angle to match the lower bearing. A normal fork crown with the relevant separate crown race will work.

A normal fork crown with the relevant separate crown race will work.

I did enquire about this in Sigma and they said that the crown races just aren't available separately, unless i can use a non-Pinarello one? Would there be any chance I could replace the whole headset with a non-Pinarello one? (I have a feeling the answer is going to be no).

Check the bearing diameters and chamfer angles - it's probably a standard size, most likely Campagnolo 45°/45° but maybe the more common Cane Creek etc. 45°/36° if the frame was made in China/Taiwan.

I'm not sure I know how to measure the angles. From looking at cane creek's headset fit calculator, and other headset information, i think this is what I'm after http://www.canecreek.com/component-headsets?browse=Fitment&name=IS42&product=40.IS42%20Tall%20Cover#40.IS42%20Tall%20Cover which is for 45/45. Also found this http://www.slanecycles.com/cane-creek-aheadset-is-integrated-1-18-p-19555.html?language=en&currency=GBP but there's not enough information to be sure (does say 45/36 on it though). Way out of my depth with all this.

Measure the bearing chamfer with a set sqaure - if it's 45°, the right angle of your set square will sit flat on both chamfers. If it's nowhere near, it must be 36°

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