Author Topic: New/Old Bob Jackson World Tour  (Read 649 times)

New/Old Bob Jackson World Tour
« on: December 04, 2019, 09:45:14 pm »
Hi folks,

I just bought this Bob Jackson world tour from a guy on ebay for £200 and I'm confused by a couple of things.



The head tube looks a lot shorter than other BJ world tours that I've seen (I don't know what age this is - it's made from 531). Have they changed the geometry at any point? And that leads to my other bit of confusion about geometry in general. A touring bike is supposed to be more relaxed, but the head tube on this is short, and the top tube is longer than the seat tube. Shouldn't all of that be the opposite? I'm 5'10" with an 87 cm inseam (short body, long legs), so wanted something very relaxed for winter and light touring. This is a 54. Would I actually be more upright on a larger frame? Would the reach be about the same but the seat tube longer?

Cheers all...




Re: New/Old Bob Jackson World Tour
« Reply #1 on: December 04, 2019, 09:47:38 pm »
Dammit. How do I insert a pic?

https://ibb.co/7S52Cw0

Re: New/Old Bob Jackson World Tour
« Reply #2 on: December 04, 2019, 10:23:47 pm »

S2L

Re: New/Old Bob Jackson World Tour
« Reply #3 on: December 05, 2019, 08:22:48 am »
In a traditional frame with a horizontal top tube, the height of the head tube is simply dictated by the size of the frame (length of the seat tube)... angles make very little difference.

It does look like a fairly standard 54 frame to me... I am not sure how else it is supposed to look like.

Re: New/Old Bob Jackson World Tour
« Reply #4 on: December 05, 2019, 08:48:18 am »
Whatever the angles that is an absolute steal at £200.
Hear all, see all, say nowt

Re: New/Old Bob Jackson World Tour
« Reply #5 on: December 05, 2019, 02:47:47 pm »
Don't think it is a World Tour as it does not have front fork bosses for rack nor does it have bosses for three bottle carriers. However it is a lovely bike and well worth what you have paid for it. The current World Tour is 631 tubing.
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Re: New/Old Bob Jackson World Tour
« Reply #6 on: December 05, 2019, 10:03:48 pm »
one of the options  when ordering a BJ is an extended head tube.I think its an early one, maybe 1970's 80's,

Re: New/Old Bob Jackson World Tour
« Reply #7 on: December 05, 2019, 10:30:40 pm »
I dunno if it is just the photo or what but it looks as if it has a high BB, a steep head angle as well as a long-ish TT.  To me it looks more like a 'cross frame that has been refurbished with mudguard eyes, rear rack bosses etc than anything else.

Remember that BJ's models have changed as time has gone on and many of their frames used to be custom made too; the idea that they might all be the same as one another and/or the same as current models is just plain daft.

  It might well be a much older frame than you think; I can't be sure from a single photo but the fork looks like the 'old' 531 pattern that was used in the 1970s, with a more extreme oval section and much slimmer tips to the blades. [If so it will ride beautifully, BTW.]

If the frame is older then the rear end spacing may be either

- still set narrower than is standard today or
- reset to a wider standard eg 130mm.

If the latter then it is not unusual to be able to see that the seat stays are no longer perfectly straight.

[edit; I've taken a closer look at the photo and there are good signs that it is a much older frameset that has been modified in more recent years; AFAICT there is a stop under the DT for band-on levers, the front mech cable run has a tunnel guide on it (that went out of fashion in the 1970s) and (again it is not possible to be sure from a single photo) it looks as if the canti-bosses (on the fork but not the stays) are set to the 'old' spacing (~65mm) rather than the more recent MTB-inspired ~80mm spacing.]

cheers

Re: New/Old Bob Jackson World Tour
« Reply #8 on: December 05, 2019, 10:42:41 pm »
Whatever it's a really nice bike. Slightly small for you, perhaps (sorry). I ride that size and I'm a good 1.5" smaller than you. Because top-tube length is roughly proportional to seat-tube length, it may be hard to get the bike long enough for you and still relaxed.

Re: New/Old Bob Jackson World Tour
« Reply #9 on: December 06, 2019, 11:01:15 am »
That's all really interesting. Thanks for the insight. I sent an email to BJ with the frame number to see if they can give me any info out of interest. Donald wrote straight back and said it would be 85/86 but I'd have to pay £25 for full detailed info. I might do that.

In terms of the size, because my body is short, the reach when i'm on the hoods feels okay. Just need to get the bars up a bit. Might cycle over to Spa and see what they say about it.

But, yeah, I thought it was a steal at £200. Aside from the saddle that i've put on, it's exactly as I bought it. It's a mixture of LX and 105 with Mavic rims that are true.

I just need to get out on it to see how it's all running.