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 Post subject: Head angle
PostPosted: Mon Dec 15, 2008 7:47 am 
Old School Grand Master
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Location: North Yorkshire
Head angle is spot on at about 69 69,5 deg, so not too tall! Sids look long travel as they have short slider/lowers but axle 2 crown is as low as anything out there as they are an XC race fork.
If you don't care about looks, your on the wrong site bro! :o


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PostPosted: Mon Dec 15, 2008 9:07 am 
retrobike rider
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I assume after sag it will settle to the more conventional riding angles of 70 to 71deg.


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 Post subject:
PostPosted: Mon Dec 15, 2008 9:14 am 
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FluffyChicken wrote:
I assume after sag it will settle to the more conventional riding angles of 70 to 71deg.

U got that the wrong way round! the bigger the angle the steeper the fork/head 70deg is steep 67 slack. My Merlin XLM is 70.5 which is very twitchey and steep. 69/69.5 is considered the norm for a trail bike, slacker for FR/DH, but tighter for an XC race bike.
I know what you mean tho :wink:


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 Post subject:
PostPosted: Mon Dec 15, 2008 9:24 am 
retrobike rider
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Sag would steepen the angle, would it not ?
(since there is no rear sag here)
or is my brain fried this early in the morning.

70 to 71 being the conventional head angle for retro bikes (we're in pre1998 here, so I think we only have XC and DH ?)

P.S. that Thomson stem does look nice though 140mm with 15degs is equivalent to 135.2mm with zero rise (using trig).
So should be spot on if the current stem is fine.


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 Post subject:
PostPosted: Mon Dec 15, 2008 10:37 am 
The Guv'nor
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bar/stem/end combo aside that looks good.

Not often a fan of the neo-retro or retro-modern style but it works well there. The silver bits on the silver frame are also quite good.

The bar/stem/end combo isn't great. Black stem definitely needed. Risers and bar ends. Well, enuff said...


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 Post subject:
PostPosted: Mon Dec 15, 2008 12:43 pm 
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Location: Platsa, Messinias, Greece
I think that any stem over about 100mm long looks wrong with riser bars and does your technical descending no good either. In fact all this long stem, stretched out riding position is something I wouldn't like to go back to now. Provided that the top tube is long enough (which for me is 22.5" - 23") I think that short (70mm) stems (and risers, of course) are the way to go.
The idea that it's not possible to climb well with shorter set-up bikes is just not true, in my opinion - when you're all stretched out (long stem, saddle shoved right back on the rails) you can't move around the bike easily to get your CofG where you want it. This goes for climbing, descending and everything in between.
Maybe not for tarmac or smooth-as-tarmac fireroads, but then who wants to ride an mtb there anyway ??


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 Post subject: Thomson
PostPosted: Mon Dec 15, 2008 7:33 pm 
Old School Grand Master
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I think its a bit more than 15 deg as it is only 132mm.
70/71 is very steep, but there are other factors! older forks even suspension, had castor or forward offset too! so this actually slackened the head angle even more, depending on whether the fork axle was leading dropout or online! Rigid forked bikes granted had steep head angles, but forks had a lot of lead, so this nullified most of this! When you put suss forks in it gets complicated! Its all down to how it rides at the end of the day and trial and error tends to be the way unfortunately. Modern forks tend to have stanchins in line with the steerer tubes.


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 Post subject:
PostPosted: Mon Dec 15, 2008 8:23 pm 
retrobike rider
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It's all about the rake in the end really.

but we're falling well away from talk about this bike.

side
RM Altitude 1991 - 71 rigid (syncros) & guess at 70 to 70.5 with retro-fit MAG's on , 1992 version corrected this to 71.5 with MAGs on.

RM Fusion 1992 - 70.5 (but 70 I think as the frame is small and a Short top tube version so it was built slackened)

Marin Bear Valley SE 1995 'suspension ready' - 70.5 degree.


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 Post subject: Head
PostPosted: Mon Dec 15, 2008 8:32 pm 
Old School Grand Master
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All pretty steep then, especially with Sag! Not much good for the steep downhills around here!


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 Post subject:
PostPosted: Mon Dec 15, 2008 8:50 pm 
retrobike rider
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Obviously you need to create the right position, but such a long stem as that will really deaden the handling, especially as the SID is already making the head angle slacker than the frame was designed for.

In any case, if the frame really is only ’a tad’ small, you may well find when you get used to it that you don’t really need such a huge stem. That’s a size 17.25 I think, and the next size up was an 18.5, which was only half an inch longer, 12.5mm. So a 140 stem could be over-kill, especially as you have the bar ends for climbing.

To be honest, it’s only helpful to say that the stem/bar/bar ends combination is just about the worst-looking I’ve ever seen, and such a shame when you’ve got such a fine frame and forks to start from. If you tried a 120/10 stem, with flat bars and bar ends, you would find that the bar height was more or less as it is now and the steering would be more like being as sharp as Joe Murray intended.

Superb frame, I'm really jealous as that's just my size and I'd definitely prefer a D'Jab to a Hei Hei. Is it right that you pronounce it DeeHab?


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