jeffieh

A Kiwi O'Brien, that is. Signed by Liam O'Brien, and built in all likelihood by kiwi veteran framebuilder Eddie Bosomworth . Never thought I'd get to own a 753, but there it was on trademe a couple of years ago, going for a song. Cost around USD130 without wheels. Must say it's not my fave ride (sorry, but how could any bike compare with an '82 Pinarello?). You really feel the bumps. Nice to own though, and in pretty good original condition.

My question to all you northerners out there, is have any of you heard of O'Briens or Bosomworths? Down this end of the world, Bosomworth 531s were the dream of every bike loving boy through the dark days of 1970s import protection. Eddie earned his rep - builders didn't get to play with 753 unless they knew their stuff, eh?

And if you have a 753 in your collection. I'd love to see it.

East Hill

Where is Sianelle when you need her?

Lordy, that is a spectacular paint job!

(and if I have not already welcomed you, then Welcome to Bike Forums ! )

East Hill

tricky 

I thought I was looking at 3 different bikes when I looked at the pictures one by one.

Your assessment of the ride coincides with how the seatstays come into the seat tube so low like that. I bet it is a great sprinter, though.

Reminds me of my friends coppi.

jeffieh

Yeah Tricky. I was thinking that was why the ride was so rough on the old spine. And yes, it does get up to speed rather quicky (arguably a liability when you're not in, err, optimum shape).

lob753

hi came across this just now, i am Liam O'Brien and i can asure you i never put my name on another bulders frame, they on the other hand may of to sell product. but the one in the pic is mine, how do i know? just do mate

luker

good to hear that you're still with us, and welcome to Bike Forums, C&V style! I don't believe I've ever seen another of yours, although we live a good long distance apart...

jeffieh

OK. I take everything back about the frame maybe being built by E Bosomworth.
The man himself has spoken. As the rest of you know, only the guns got to work with 753. Maximum respect to you. Jeff
Ps - any old frames hanging up in your garage? If so, PM me

javal

Spectacular bike! I like the seatstays agressive angle! What year?

cs1

This is my offering for the 753 bike show. While not a first year it the first model Waterford made after the Schwinn bankruptcy. It was originally a Team Mak red, white and blue with Campy 8 sp. I sold off the groupset and had it repainted in yellow. Even though I don't race I can feel the difference between 753 and 531. It's got a Daytona 10 sp group with Zonda wheels.

Spinz

Outstanding bikes. The paint on the O'Brien is super cool. Lp

johno'brien19

hi im john o'brien and my dad made this bike, he spoke to you before. he has great interest in this o'brien 753 and so do i, my dad has no trace of the bikes he made and i would love to suprise him by getting him one of his bikes, would you ever sell it to me? and how much? name you price! please consider what i have said. thank you. john

jeffieh

Hi John,
I've been meaning to get back to you on this for ages.
You must have the seen the bike on trademe? Yes, I had it listed. Loads of views and watchers, no bidders. I had the price set real high because...well...because in my heart I didn't really want to sell it.
Your dad built very good bikes!
My O'Brien fits me perfectly, is in VERY good nick, and is made from highly exotic Reynold 753. These are all big ticks.
The downside is it's not a comfortable ride. Partly the short seat stays, partly the fork rake (maybe, haven't ever checked it), but it rides hard. Very fast and light, of course, But being lazy and old I prefer a frame that's a bit more forgiving.
But I still keep it as one of my four ready-to-ride bikes on the wall of the garage. It's in good company: a 1982 Pinarello Record, 1984 Peugeot PSV, and a 1976-ish powder blue Zeus Pro. The O'Brien is a very classy bike that isn't out of place in that kind of company. And a bike that gets compliments pretty much every time I ride it. No kidding.
So no, I can't sell it to you John. It was silly of me to ever try.
But.
If you'd like to have it for a while, to show your dad, ride, hang on the wall - whatever - give me a call or email. It's the least I can do. I can live without it for a month or two if I know it's somewhere safe.

Warm regards

Jeff Howell
021 380 882
jeff@morepork.co.nz

Nessism

753 is a very thin tubeset, so accordingly it builds up into a more flexible frame than a similar 531 frame that has thicker tubes. Of course, differences in the build configuration can make a difference though - Waterford for example built some OS sized 753 frames which most likely would feel more ridged than a STD sized tubed 531 frame. The details do matter but it's a matter of physics that 753 is flexy, not stiff.

lob753

Totally the opposite mate, the 531 is soft and flexible, the 753 is thinner and stiffer, different metals totally

devinfan

LOL there's zombies and then there's Zombies... it must've taken some serious voodoo magic to being this thread back!

Scooper

Hi Liam,

I find your comment that 753 is thinner and stiffer than 531 somewhat confusing.

The Young's Modulus (modulus of elasticity, or "stiffness") of both 531 and 753 is the same: ~200 GPa. In fact, all steels have virtually the same stiffness. 531 and 753 have exactly the same manganese-molybdenum chemistry, but 753 is heat treated to provide higher ultimate tensile strength and yield strength. Because 753 is stronger it can be drawn with thinner walls to make the tubes lighter.

Nessism is correct about 753 not being as stiff as 531. Because they have the same Young's Modulus, its thinner walls make 753 flexier than 531 for a given diameter tube. Nessism correctly points out that by going to oversized tubing, 753 frames could be made as stiff or stiffer than 531 frames with standard sized tubing and still be lighter because of 753's thinner walls.

lob753

im not a chemistry buff mate, but im sure if you contact Reynolds they
will put it in technical terms for you. the 753 is absolutely the
stiffest tube on the market and the 531 is there low end tube, but im
only a licensed frame maker what do I know. lol

this might explain it to you, as you forgot to factor in the tensile
strength
753 - Heat-Treated Manganese-Molybdenum. The most exclusive tube set
from Reynolds. Essentially 531 made with reduced wall thickness and
heat treated to increase tensile strength. UTS: 1080-1280 MPa (70-83
Tsi, 157-186 ksi) Complete tube set of 11 tubes (Frame 8, Fork 3). 753
can only be lugged and fillet-brazed with an alloy of 56% silver below
700 degrees Celsius and sale is restricted only to approved builders

wintermute

(Ultimate) tensile strength has nothing to do with stiffness. It is the amount of tensile (not compressive) stress the material can handle before it fails. Scooper hit the nail on the head. But I'm just a Professional Engineer.

BTW, that is one CRAZY colored bike, in a good way. I don't think you need reflectors for night riding on that thing.

Why am I helping feed the zombie?

Someone call an exorcist.

lob753

im not a chemistry buff mate, but im sure if you contact Reynolds they
will put it in technical terms for you. the 753 is absolutely the
stiffest tube on the market and the 531 is there low end tube, but im
only a licensed frame maker what do I know. lol

this might explain it to you, as you forgot to factor in the tensile
strength
753 - Heat-Treated Manganese-Molybdenum. The most exclusive tube set
from Reynolds. Essentially 531 made with reduced wall thickness and
heat treated to increase tensile strength. UTS: 1080-1280 MPa (70-83
Tsi, 157-186 ksi) Complete tube set of 11 tubes (Frame 8, Fork 3). 753
can only be lugged and fillet-brazed with an alloy of 56% silver below
700 degrees Celsius and sale is restricted only to approved builders
531 and 753 were both originally same size tube. oversize came much later

lob753

well you must be a clever guy, because if your right then that makes Reynolds, wiki and all the professional frame builders wrong. but maybe we are just zombies and you are the clever one. maybe you could explain why a lot of riders for long races changed the front forks for either 531 or carbon fibre to make bike less stiff? oh you were probably in your nappies then lol

sloar 

what are nappies?

Scooper

Diapers.

sloar 

thats what i thought, never heard that one before.

wintermute

Many shubs and zuuls knew what it was like to be roasted in the depths of the Sloar that day, I can tell you!

miamijim

First, I was like, WTF is a 'trademe' and then I like, whoa, easthill's back from the dead.

All we need know is for Kurt to make a cameo....