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Old 09-05-06, 11:01 AM   #1
piwonka
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Bob Jackson track frames

Does anyone know what the "off the peg" geometry for the BJ track frames are?
I sent an email to them but don't really expect a reply too quick and I'm not too interested in making a call from the US to the UK.
I'm curious about headtube and seattube angle, and chainstay length mainly.
I've read that they are pretty relaxed track geometry, can anyone comment on this?

this guy told me that his frame is "off the peg".
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Old 09-05-06, 09:26 PM   #2
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what makes that bike looks odd are the wheels and the ROAD fork. Off peg means that it was built in series at manufaturers specifications. SO basically u have there a fixed gear frame built to ride in the street. Even the fork match the frame, im quite sure a real track fork will screw up the whole geometry. But well, Bob Jackson build racing track frames also that Im quite sure are very nice also... to finish what else u can xpect of a £295.00 frame? Go to bob jackson web site and take a look...
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Old 09-06-06, 09:25 PM   #3
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the front end looks fairly relaxed for track, but the rear looks pretty tight. probably made that way for easy ride-ability.
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Old 09-07-06, 08:11 AM   #4
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I actually got numbers...

The 22" frame has a 22" (56cm) top tube
The headtube angle is 73* and the seattube is 75*...rake is 1.75" which should be 44.5mm.

All Vigorelli frames have 11" (28CM) BB heights and 15.75" (40cm) chainstays.


My beater conversion already has 73*(atleast that is stamped in the lug) headtube and I think 40cm chainstays....56cm seat and top tube lengths...what's the point in the same geometry on two bikes???

I was hoping for something more around a 74.5* seat and head angle with around a 38mm chainstay. I guess I could get a custom one.
I wasn't sure what numbers to specify for BB height and rake....

I'm gonna ride a 55cm Pake and see what it feels like that has a 55cm top tube so if that feels good i might get 57cm seat length with 55cm toptube, 74.5* angles on both seat and headtube, 38cm chainstay length.
11" BB height and not sure on the rake...the custom Pista comes with a steel fork....any recomendations on BB height and rake???

We have no Velodrome here (but there are petitions for one i think) so I'm just looking for a tighter more responsive bike to ride...right now atleast...I think I've only ridden like 200 miles in the last month and a half so I don't ride on long rides that much.
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Old 01-04-07, 04:17 PM   #5
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A friend of mine bought a BJ frame off the rack and had a series of problems, finally we realized that the rear triangle was misaligned by 5mm!
I don't want to hate, they are nice frames, however, I think there is a tendency to assume that handmade frames cannot be wrong and that factory frames are always less than...

So, nice frames but doublecheck the lines befoe you build. I mean its steel so, it is really easy to correct.
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Old 01-14-07, 03:57 AM   #6
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I think the off the peg has a grasstrack style geometry, so slightly relaxed angles, more fork rake than you might expect and greater tyre clearances. Also a very high BB for cornering on a flat track, and the fork is drilled for a brake. These characteristics obviously transfer well for street FG riding, but not so great on a banked velodrome. Shell out the extra 55 quid and go custom, enjoy a bike built exactly the way you want it.
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Old 01-16-07, 12:47 PM   #7
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Quote:
Originally Posted by Rattlebag
Shell out the extra 55 quid and go custom, enjoy a bike built exactly the way you want it.
that's what i did, i'm happy.
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