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PostPosted: Thu May 08, 2008 10:09 am 
Dirt Disciple

Joined: Tue Jan 09, 2007 10:50 pm
Posts: 47
Location: London
Hi,
i picked up a Raleigh Ti frame recently and wonder if anyoe knows anything about them. I've looked on the net but i'm not sure if i've been looking in the right places. It's not the bonded dynatech type and looks more like a traditional Litespeed. It's lovely, slightly polished and (seems to be) crack free. It's also amazingly light, i've not had a ti frame before but it's turning me.

Thanks,


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 Post subject: Frame
PostPosted: Thu May 08, 2008 10:27 am 
Retro Guru
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Joined: Thu Oct 18, 2007 9:46 am
Posts: 328
I've had one of these too, believe it or not!

There are two 'types', one with a standard round section downtube and the other with a oval 'aero' style downtube.

The one I had was almost identical to a Litespeed Classic frame.

The story is that they are made with military grade Russian titanium. They don't shine up as brightly as say, a Litespeed or Merlin but they remain light, sprightly and very hard wearing.

You can use the old scotchbrite trick, cut a long strip, wrap it round the tube and pull back and forth like towel-drying your back. This will give you the lustre you will want.

I had mine for a few years with a Record groupset and even did the E'Tape du Tour on it. They are a bit flexier than a good 753 or 531c frame of the same size but a bit lighter and certainly wont rust.

Partner it with good forks though. Try looking on eBay for a 1" pair of Litespeeds (made by Kestrel). You wont go wrong there.

Oh, and get the BB reamed. It can destroy alloy cups if the threads aren't perfect.

All the best.

NB: Coming to think of it, I wish I still had that frame. If you have a source for a 58/60cm one, please let me know. It had a certain 'rightness' about it.


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PostPosted: Thu May 08, 2008 3:16 pm 
Dirt Disciple

Joined: Tue Jan 09, 2007 10:50 pm
Posts: 47
Location: London
H,

thanks for the info. Mine is a 55cm sans headtube badge and has round profile tubing. Was an ebay find and is in very good condition.
I'll be dumping a collection of 9spd campag stuff on it pretty soon and take it out for a ride. Here comes the summer!

You don't happen to know what years they were made do you?

Thanks again,


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 Post subject: Frame
PostPosted: Thu May 08, 2008 7:14 pm 
Retro Guru
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Joined: Thu Oct 18, 2007 9:46 am
Posts: 328
I think they were made right up to the end of Raleigh 'Special Products' which would be late 1990's.

http://www.hadland.me.uk/raleigh.htm

and

http://homepage.ntlworld.com/catfoodrob ... tory1.html


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 Post subject: Raleigh titanium
PostPosted: Sat May 10, 2008 11:31 pm 
Devout Dirtbag
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Joined: Tue Oct 30, 2007 1:28 pm
Posts: 133
Location: The people's republic of South Yorkshire
I had one of these too in a 54cm and really regret selling it though I actually made money on it after having it for 2 years!. The titanium is Timet, commercial grade 2 titanium (not an alloy!) which doesn't make much difference to the ride or weight of a titanium frame, but does allow crack propogation and hence limits the fatigue life of the frame.

The frame was superb, I had the oval downtube version and it was superbly light and stiff around the bb giving great acceleration, I just got used to Colnago geometry and went off the steering feel. It has a 26.8 or 27.0mm seat tube on it which made it awkward to source a seat post ( I used a USE 25.0 with a shim).

I got it from Samways in Derby having searched the country, the shop keeper reckoned it was the last of the RSP stock, he even gave me the sticker set for it and a head tube badge, claiming they never really got finished at the factory.

A superb bike, you've got yourself a true bargain.

The finish is shot peened to stop crack propogation, DO NOT POLISH THIS FRAME! you will introduce surface microcracks and limit the frames lifespan. (I am a materials scientist so do have a clue).

Enjoy the frame,

Stuart


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 Post subject: Frame
PostPosted: Mon May 12, 2008 12:55 pm 
Retro Guru
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Joined: Thu Oct 18, 2007 9:46 am
Posts: 328
I wonder why shot-peening is a technique used to avoid crack formation?

I would have thought a smooth surface would be less prone to cracks as it has a smaller surface area and therefor less areas for cracks to propagate from.

The frame I had was just 'dull' and not shot peened. I could be wrong though - but it polished up nicely!

Let us know about this surface thing if you can plasma2873. And what is Grade2 Titanium?

Cheers!


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 Post subject: Raleigh titanium
PostPosted: Tue May 13, 2008 10:01 am 
Devout Dirtbag
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Joined: Tue Oct 30, 2007 1:28 pm
Posts: 133
Location: The people's republic of South Yorkshire
Polishing is actually a procedure introducing millions of tiny sharp edged scratches into a surface. It is the acute angle at the base of these scratches that acts as a stress concentration and crack propogation point. We are talking on a micro scale here so it is hard to imagine. Polishing acts to dazzle by light reflection but view a polished surface under an electron microscope and you will always see scratches.

Shot peening introduces no such acute angled scratches and so there is less chance of crack propogation.

Commercial grade 2 titanium is a very pure grade of titanium, I'm not sure if Timet still make it, but is a reference to the degree of refinement in the metal extraction process.

If you look at the fatigue cycle of the materials you would have to be doing an amazing mileage per annum over a long period of time on some shocking roads to fail one of these frames. I don't have the figures to work it out. Check the book "bicycling science" for more info (or study materials for 10 years at Sheffield university!)

Regards


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 Post subject: Ti
PostPosted: Tue May 13, 2008 7:17 pm 
Retro Guru
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Joined: Thu Oct 18, 2007 9:46 am
Posts: 328
Thanks for that comprehensive explanation.

Sorry to go a bit off-thread here but these frames are nice - and if I see another in my size I will be going for it.

All the very best with the Raleigh. It'll be a beauty!

Post some pics.

Cheers!


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 Post subject: Re: Raleigh titanium
PostPosted: Thu May 15, 2008 3:37 pm 
Old School Grand Master
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Joined: Wed Feb 20, 2008 12:21 pm
Posts: 5785
Location: Lost in Translation
plasma2873 wrote:
Polishing is actually a procedure introducing millions of tiny sharp edged scratches into a surface. It is the acute angle at the base of these scratches that acts as a stress concentration and crack propogation point. We are talking on a micro scale here so it is hard to imagine. Polishing acts to dazzle by light reflection but view a polished surface under an electron microscope and you will always see scratches.

Shot peening introduces no such acute angled scratches and so there is less chance of crack propogation.

There's also the effect of putting the surface layer in compression:

http://en.wikipedia.org/wiki/Shot_peening

Quote:
Peening a surface spreads it plastically, causing changes in the
mechanical properties of the surface. Shot peening is often called
for in aircraft repairs to relieve tensile stresses built up in the grinding
process and replace them with beneficial compressive stresses.

Plastic deformation induces a residual compressive stress in a peened
surface, along with tensile stress in the interior. Surface compressive
stresses confer resistance to metal fatigue and to some forms of
corrosion.

Mavic now peen some of their rims to reduce the risk of cracking.


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 Post subject: Shot peening
PostPosted: Thu May 15, 2008 4:28 pm 
Devout Dirtbag
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Joined: Tue Oct 30, 2007 1:28 pm
Posts: 133
Location: The people's republic of South Yorkshire
I didn't want to enter into the field of surface tension and compression but you are spot on with your comments there one eyed Jim.

If you ever come across one of these frames languishing in an old Raleigh dealers, buy it and don't sell it as us previous owners really regret it now.

Regards


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