Geometry advice needed on a prototype Merckx frame

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Fatbiker
Posts: 874
Joined: Tue Aug 08, 2006 1:41 pm

by Fatbiker

Image


I was thinking about maybe building this up for myself. It is a prototype Merckx titanium frame. I have no idea whether I will fit on this frame though, seeing as my expertise on geometry is pretty much non-existent. My instinct says no, giving the short head tube, but the top tube says yes. For your information, my length is 1,90m and my inseam is 90cm (if I recall correctly). Any thoughts on this matter?

The geometry specifics are:

Head tube: 11,9 cm
Top tube: 61 cm (C-C)
Seat tube: 54,5 cm (C-C), 55,5 cm (C-T)
Seat tube angle (approx): 63 degrees, measured between top tube and seat tube
Head tube angle (approx): 69 degrees, measured between top tube and head tube.
Chain stay length: 48 cm, measured from center of BB to the back of the dropout

More pictures of the frame can be found on my Flickr page: http://www.flickr.com/photos/quality_vintage_bikes/

Super_fast
Posts: 337
Joined: Tue Nov 01, 2005 9:36 am

by Super_fast

The top tube is this long due to the extreme seat tube angle. When you would compare the reach of the frame, you'll see the reach of the frame also is far to small.

by Weenie


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bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

That's interesting because I too have a Merckx frame with stretched dimensions. And strange angles. Mine's a TT frame but I always thought it had to have been custom made for an individual with very long torso and arms. Sort of ape-like. Mine also has a number hanger.

So, if anyone knows who Eddy might have been building these for in the late '80's, please chime in.

In our terms you are 6' 3", so a 61cm TT while being perhaps a cm or 2 too long should be workable. I have a seatpost with zero setback and the shortest stem I could find, to make mine rideable for me. And I'm "only" 6' 1".

The bar height is a different issue. It all depends on what drop you can ride with. I'd be dummying up a saddle at your height and then looking at stems to see what you can achieve and whether it's likely to be rideable.

Here's mine. Tubing is modified Columbus TSX.

Image

I see OP is in the Netherlands. My frame came to me from there. Coincidence??
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

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DMF
Posts: 1062
Joined: Sat Dec 06, 2008 10:14 am
Location: Sweden

by DMF

I can never seem to wrap my head around these old odd STA's... 63 degrees. I mean even with a by todays standards extremely slack 71 degree and a 35mm setback seatpost, you're still off by like 4,5cm in seat position even with an inline seatpost.

And these are seldom tourers, hey have proper drop. So who the heck rode these things? The hip angle must by all accounts just have been absolutely horrible?! And I do ofcourse not buy the KOPS-crap, but even that seems to have some limitations before knee propblems strike...

Don't get me wrong, that is one seriously awesome looking frame!!

I just don't understand the reasoning for these STA's.

GT56
Posts: 570
Joined: Fri Jun 05, 2009 9:40 am
Location: Switzerland

by GT56

isn't this a younger version of the frame that steve bauer rode paris roubaix early 90s ?

google steve bauer paris roubaix bike and you'll know what i mean

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bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

GT56 wrote:isn't this a younger version of the frame that steve bauer rode paris roubaix early 90s ?

google steve bauer paris roubaix bike and you'll know what i mean


I looked this up and found this:

Image

http://www.bikehugger.com/post/view/the-ugliest-eddy-merckx-ever

OP's frame does not look quite as radical, but there's definite similarities. The writeup confirms that this was custom geometry.

It would help to put a couple of wheels on the frame for another photo.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

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ergott
Posts: 2870
Joined: Tue Apr 18, 2006 3:03 am
Location: Islip, NY
Contact:

by ergott

I don't know how you measured, but that head tube angle doesn't look like 69deg.

I would make sure you are measuring with the dropouts level and headset in place. Don't assume the top tube is perfectly level.

Fatbiker
Posts: 874
Joined: Tue Aug 08, 2006 1:41 pm

by Fatbiker

I suppose the slack seat tube angle explains why the head tube is relatively short, seeing as a larger seat tube angle also lowers the saddle position at a given saddle height. On Steve Bauer's bike Merckx spec'd a very short stem, which would explain the relatively long top tube. Anyway, if I do really want to ride this frame I will need to find a high tail saddle. A damn shame I sold my Selle Ultra Pro (Corima) saddle last year.

Down at the Retrobike forum someone suggested this frame may have been built for Olaf Ludwig when he rode for Telekom.


Image

Valbrona
Posts: 1629
Joined: Fri Oct 28, 2011 3:25 am
Location: United Kingdom of Great Britain and Northern Ireland

by Valbrona

That's no Steve Bauer-type frame, but a regular frame one of the pro's would have been on, many of whom used very slack seat angles compared to the frames they ride these days.

Fatbiker
Posts: 874
Joined: Tue Aug 08, 2006 1:41 pm

by Fatbiker

I took a picture this morning of the frame with some wheels in it:

Image

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bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

Hardly a "regular" frame now is it?

48cm chainstays when "regular" would have been 41cm.

I think that your main problem is going to be trying to get fitted to that thing. In the thread I posted, it looks like Bauer tried it a few times and gave up.
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

User avatar
bikerjulio
Posts: 1900
Joined: Fri Dec 11, 2009 10:38 pm
Location: Welland, Ontario

by bikerjulio

Perhaps build up a cool city bike? :)

Image
There's sometimes a buggy.
How many drivers does a buggy have?

One.

So let's just say I'm drivin' this buggy...
and if you fix your attitude you can ride along with me.

http://www.youtube.com/watch?v=GekiIMh4ZkM

Geoff
Posts: 5395
Joined: Sat Dec 13, 2003 2:25 am
Location: Canada

by Geoff

That is a really special frame. Great find.

Fatbiker
Posts: 874
Joined: Tue Aug 08, 2006 1:41 pm

by Fatbiker

No matter how hard I try to imagine a way to make this frame work for me, in the end it just isn't right for me :cry: .

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legs 11
Posts: 3602
Joined: Tue Jan 23, 2007 11:22 am
Location: Leg hurty

by legs 11

Try not to worry too much dude, I don't think this frame will fit anyone who is human shape...lol.
Valbrona......Just no, this was an odd experiment, it is in no way a standard frame or typical of pro frames in 'the old days'.
It is true to say that seat tube angles were slightly slacker back in the day, but not anywhere near this extreme.
It belongs in a museum along with various other odd things they made in the name of experimentation.......the full suspension Bianchi, the 'V' frame mountain bikes, the dog leg cranks etc. :noidea: :wink:
Pedalling Law Student.

by Weenie


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Great Prices ✓    Broad Selection ✓    Worldwide Delivery ✓

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