Front suspension forks... how does the sizing work?

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Front suspension forks... how does the sizing work?

Postby MJF » Sat Mar 01, 2008 8:21 pm

I've just discovered a split shaft seal on the hybrid. Being low-end RST Omni forks, I'll assume at this point that the seals are not available to allow them to be rebuilt. And I quite like the idea of going for non-suspension forks anyway... The fork isn't leaking oil yet, but Murphy is bound to make an appearance soon, so I'd like to get this sorted sooner rather than later.

So - 700C front road forks make sense, the brake pivots are in the right place. 26" MTB forks ditto. So, how does it work for Hybrids??!? Are my front forks specific for a hybrid, or is it the V-Brake parts that are different, or is it just assumed that the slots on the V-Brake carriers have enough adjustment to put the pad on the rim?
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by BNA » Sat Mar 01, 2008 8:40 pm

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Postby Bnej » Sat Mar 01, 2008 8:40 pm

If you have 700c wheels then get a 700c fork, and the brakes ought to line up if you have V brakes. If you have calipers you need to make sure you get a fork that takes the same brake reach.

A change of fork will probably change the geometry of the bike a bit too.
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Postby MJF » Sat Mar 01, 2008 9:25 pm

Thanks Bej - your response got me thinking, so I googled the right thing this time ("700C suspension fork") and came up with a bunch of answers.

So - Hybrid MTB's with 700C rims need a specific fork. I bet my chances of finding one of those on the shelf at a bike shop tomorrow are somewhere between buckleys and none. :evil:
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Postby Bnej » Sat Mar 01, 2008 9:36 pm

MJF wrote:So - Hybrid MTB's with 700C rims need a specific fork. I bet my chances of finding one of those on the shelf at a bike shop tomorrow are somewhere between buckleys and none. :evil:


If you can get a rigid "suspension corrected" 29" MTB fork it may suit, I think Surly and Salsa have cro-mo ones that might suit. There are carbon ones too but they're generally disc brake only.
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Postby MJF » Sun Mar 02, 2008 6:43 pm

AAAAAAAAAAAAAAAAAhg!

Rang around the bike shops, was told by one they had the parts and to bring the bike in so they could check. They tried to 'take' my bike so they could do the job in the workshop sometime this week, eventually sold me a CrMo fork that they said would fit which, when I measured it at home (and with the knowledge obtained by an afternoon on the web), turned out not to be suspension corrected and the steerer tube was ~ 2cm shorter. That will be going back tomorrow.

I also visited the local Shogun shop which specialises in bike repairs - he couldn't tell me what suspension corrected was. The only useful thing is that one of his customers has just swapped the fork on his Shogun flat bar roadie from stock Carbon to Surly long-haul trucker because he wanted to run wider tyres, and the Carbon fork may be available - but didn't offer to ring the guy, will wait until he picks up his bike some time in the next week. But - the shogun rigid forks are NOT suspension corrected, the bikes with suspension just ride higher at the front...

Now I've spent an afternoon on research, the Surly Karate Monkey front forks appear to be the ones I'm after - ~$220.
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Postby MJF » Sun Mar 02, 2008 10:10 pm

In fact - I've now realised I have no choice. I run the seat as far back as I can already, and dropping the front of the bike would rotate the seat forwards.

So - Surly it is.
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Postby MJF » Wed Mar 05, 2008 1:16 pm

And... now the bike had a metallic brown Surly Karate Monkey front fork to complement the metallic silver frame.

The front is slightly higher than it was previously (~2cm), so I had to adjust the seat angle, but initial riding impressions are : no real difference to ride quality (I used to have a lot of preload set on the suspension) and the bike is noticeably lighter.
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Postby gsxrboy » Wed Mar 05, 2008 1:26 pm

We probably need some before and after photos 8)
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Postby MJF » Wed Mar 05, 2008 7:36 pm

Lol - maybe not such a good idea.

My cycling partner at work went down this afternoon for a look, and when he came back said "I'd rather kill myself than ride a bike that ugly".

I'm thinking about painting it a more suitable colour... but perhaps I'll just leave it as it is - might keep people from stealing it. :P
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Postby Bnej » Wed Mar 05, 2008 9:45 pm

I always go on the principal that you ride it you don't look at it. How bad it looks is a problem for other people to deal with. ;)
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Postby Whitz End » Sat Mar 08, 2008 8:34 pm

Uh, might be a little off track but I believe Manitou used to make the 'Luxe' suspention fork for hybrid. SR Suntour still make a trekking serious also...uh..."TX" I think they were named.

RST 'Omni' series of suspention forks were your plain-Jane elastomer set up and are unlikely to have any oil whatsoever in them. that said, if any residual rings are present, it would be grease. You might be able to get by but as soon as water/dirt penetrate in, there your in trouble.

Rigids are likely to be the better way to go, especially if you are predominatly on road. Hybrid forks are notoriously basic when it comes to performance...then again, they dont really need to perform as such...not exactly hucking gutters now are we.

Good luck
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