Surly LHT fork on a Mountain Bike frame?
 

Hey folks-

I'm curious about using a non suspension corrected Surly LHT fork (one for the 26 inch) on a newer steel mountain frame (Soma Groove) that has geometry for a 80mm suspension fork. It's mostly been my mountain bike, and winter commuter, but I'm wanting to turn it into a touring bike, and I'm curious which rigid fork to buy. I was thinking the 1x1, but I prefer the mid blade eyelets for a lowrider.

Will using a non-suspension corrected fork like the LHT on a mountain frame totally ruin the handling? Would it be better or worse for touring?

That would be a horrible idea. A shorter fork will cause the handling to be twitchy, which is not something you want when fully loaded. Soma has a rigid fork that is made for the Groove or you could get the Surly Troll fork which has the eyelets. The Troll was designed for a 100mm suspension fork, so it might cause the handling to be a little slower and will raise the bottom bracket, but that's better than going the other direction. Skinnier tires would help to mitigate the issue a little bit. Better yet, just buy an Old Man Mountain rack and keep the fork you already have.

Kona sells the Kona Project 2-26 inch forks in two axle crown lengths 410mm and 440mm This fork has eyelets at the dropout but not at mid fork. You can use p-clips as a mid blade mounting point here is tech instructions from Jandd on how to mount them http://www.jandd.com/Technotes/technotes_front_rack.asp

Suspension correction is about blade length, so the head tube will not be lowered,
changing the steering geometry.

So you need to match the fork crown race seat to axle distance with in a few cm.
there is some sag when you get on the bike from your weight, on the suspension fork,

so an inch shorter is probably close to design..

Get the 1X1 Surly fork and forget about using a LHT fork: http://surlybikes.com/parts/1x1_fork

Just use P clamps to install your front rack.

If 453 mm works for your frame:

http://www.nashbar.com/bikes/Product...0052_174928_-1

I'd order one. Be sure wherever you order whatever from, you can return it cheaply. Then check it for straightness when you get it.

Hi Barrettscv
Curious as to this recommendation as opposed to the Troll fork with all the bolt on ability?

After reviewing the post, I agree that the Troll fork would provide more rack options.

From FAQ at

http://www.somafab.com/archives/product/groove

"Hardtail geometry is based on a 440mm fork (approximately 80mm travel fork)".

430-450mm should do fine.

This is close:

http://classic.aebike.com/product/su...k0098-qc30.htm

OIC now it is already mentioned.

The tubus adapters for front forks are really well designed in my opinion. I've seen perfectly fine touring done with u-bolts holding the front rack on the forks. Since you're in Portland there must be a neighbourhood frame builder or two you can get to put eyelets into the fork.

Here's my notes from when I was researching replacing a Rockshox 21R on a GT Pantera for my girlfriends new commuter build:
(IIRC, I measured it at 430mm, and it was an 80mm travel fork, but I could be mis-remembering, 440mm seems to be a common replacement size for this, but as noted there are 453mm forks available as well.)

Kona Project 2: 60-70$, ugly?, eyelets, crown hole, no disc tabs, 440mm, 1040g/813g(triple butted)
disc tabbed http://www.cycle-solutions.com/Project-2-26-P4797.aspx
http://www.cambriabike.com/shopexd.asp?ID=87429
http://www.bikeman.com/KON-P2MTN440.html

IRD MTB CrMo Canti rigid 26" 440mm fork
96$ IRD 440, 40mm rake, black, unicrown, 907g, eyelets,
http://www.speedgoat.com/Catalog.asp...116&Prod=22806

$103 for Soma, canti, 40mm rake, 440mm length,
http://www.niagaracycle.com/product_...ucts_id=802955
http://store.somafab.com/socrmtbfoca.html

One One Inbred fork is 440mm.
Van Nicholas VNT TRX Alloy MTB Fork is only 420mm
IndyFab no-Travel fork is 430mm for 80mm fork replacement.


She doesn't really ride in foul weather, so I have yet to tackle the MTB conversion build, I've still got my fingers crossed that the fork I picked up will end up matching correctly, given I had to guess at how much it compresses usually. I'll dig it out of that parts box tomorrow and post which one I chose. I want to say it was the IRD, which it doesn't look like they are offering right now, but could probably be tracked down somewhere.

EDIT: Yeah, this was the fork I got --> IRD MTB CrMo Canti Fork Black, 1-1/8" Threadless, Cantilever, 26", 440mm fork, 40mm rake, black, unicrown, 907g, eyelets, 96$


I might have some more notes in an earlier draft of my research for her bike that I edited out as I narrowed down my search. If I come across those, I'll post them up too. Hope this helps!

Here is some errata from my research, quotes from sources all over the internet that I was using to inform my decision:
" Kona and Surly forks are too short at 410mm, unless you want crazy twitchy handling. Vicious and Salsa are the only two currently available that (I know of that) are the correct lenght 425mm (or so). "
" Surly 1x1 100mm for is 453mm long which would make the HT angle about 1 degree more slack, one set of eyelets, rim brake mounts, the disc caliper mount, and the line guides but it is corrected for frames designed for 100mm suspension forks. Straight blade."
" The 21 R uses the Mag fork brace, MCU spring, SL crown to give 60mm of travel while weighing in at 3.0 lb. "

And a note to myself about forks I found that I coveted, but were too rich for my blood:
Vicious Cycles forks are very expensive i.e 275+15 for fender tabs + 60 $ for low rider rack mounts, Straight blade.


All that said, I wish I knew about the Troll fork when I purchased the IRD. The Troll has mid fork eyelets and double eyelets down low, making it easy to mount both fenders and a variety of racks, and cleanly at that. Myself, I'd be tempted to cut off the disc tabs and repaint it, but then again, I'll probably experiment with discs up front at some point on one of our rigs.

I attached the Nitto Big Front Rack to an old mountain bike ('93 GT Outpost) with homemade P clamps out of aluminum stock bent to fit because the P clamps that came with it were a little small. It's holding on like a champ and I've had two large Ortlieb panniers filled to the brim with books hang off it for an 8 mile hilly ride home from work. P clamps are definitely a viable solution.