Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Clydesdales/Athenas (200+ lb / 91+ kg) Looking to lose that spare tire? Ideal weight 200+? Frustrated being a large cyclist in a sport geared for the ultra-light? Learn about the bikes and parts that can take the abuse of a heavier cyclist, how to keep your body going while losing the weight, and get support from others who've been successful.

Reply
 
Thread Tools Search this Thread
Old 12-19-12, 12:55 AM   #1
tergal
Senior Member
Thread Starter
 
tergal's Avatar
 
Join Date: Nov 2011
Location: Logan, QLD ,Australia
Bikes: Trek 4300
Posts: 790
Replacing Suspension with Rigid

Asking in here, since the crowd is nicer most of the time


As some know I use a trek 4300 for Commuting to work,

Well I noticed a few weeks ago a large amount of build up one of the pistons... tube.. stanchions.. the shiny silver things that i can not for the life of me remember their name while typing this .

Anyway ,after cleaning it and taking note there is a slight break in the seal i believe , instead of replacing it with the same suntour fork i figured i would go for a ridged fork since i only use this bike for commuting these days.

Ok so getting on with it ,

http://mountain-bikes.findthebest.co...Trek-4300-Disc

--The forks have 100mm of travel , how do you take that in to account on the ridged forks.

--What would be your suggestion on steel or aluminum



Ok just those two for now ,


Oh and yes i am still working on the other frame and bike sanding paint sucks
tergal is offline   Reply With Quote
Old 12-19-12, 01:19 AM   #2
jsigone
got the climbing bug
 
jsigone's Avatar
 
Join Date: Jan 2005
Location: San Diego
Bikes: one for everything
Posts: 8,373
I've ridden both alum and steel rigid 29er forks. While the design of the alum fork I have was very nice and the flex was comfy over the rock garden, if it failed it would just snap/crack. Which is always in the back of you mind. Though I really did try to make the fork fail, I actually cracked the top tube of my frame doing so LOL (jumping). I'd pick steel for vote of confidence, but you can't argue that against as greatly engineered alum fork.

When picking out a rigid, they will usually say something like " 80mm suspension corrected" or "100mm suspension corrected". If you get it wrong, it only changes the head tube angle by about 1*
__________________
Rule #10 // It never gets easier, you just go faster.
jsigone is offline   Reply With Quote
Old 12-19-12, 06:04 AM   #3
Arvadaman
Senior Member
 
Join Date: Dec 2008
Bikes:
Posts: 268
I have done it a number of times. I generally get a Surly 1x1 fork. I run 26" wheels.
Arvadaman is offline   Reply With Quote
Old 12-19-12, 10:37 AM   #4
sstorkel
Senior Member
 
Join Date: Apr 2008
Bikes: Cervelo RS, Specialized Stumpjumper FSR Pro, Schwinn Typhoon, Nashbar touring, custom steel MTB
Posts: 5,416
Quote:
Originally Posted by jsigone View Post
When picking out a rigid, they will usually say something like " 80mm suspension corrected" or "100mm suspension corrected". If you get it wrong, it only changes the head tube angle by about 1*
I don't know about that... I (mistakenly) put an 80mm-corrected fork on a bike designed for a 100mm suspension fork and it made the handling so nervous the bike was almost unrideable! The handling was so nervous, it was very difficult to keep the bike moving in a straight line!

My advice would be to measure from the front fork axle to the crown race bearing and look for a replacement fork that's within 5-10mm of the same length. As far as steel vs. aluminum, I don't think it makes a different. If you were going to use low-volume road tires (ex: 700x23) I'd tell you to go with steel. With higher-volume tires I don't think it matters. Aluminum road bikes are known for having a harsh ride, but my mountain and touring bikes combine aluminum forks with high-volume tires (26x1.95 and 700x35) and ride beautifully.
sstorkel is offline   Reply With Quote
Old 12-19-12, 12:22 PM   #5
jsigone
got the climbing bug
 
jsigone's Avatar
 
Join Date: Jan 2005
Location: San Diego
Bikes: one for everything
Posts: 8,373
Most MTBs are designed to handle either 80 TO 100mm forks. Swapping out 1* of head angle is like going down hill vs going up hill seating possition. It shouldn't make the front twitchy. Twitchy fronts comes from handlebars being to narrow and following the shoulder movements faster. Key to riding XC stlye 23" wide bars is to keep your head up and look forward. Another effect could be the offset was wrong/shortened, this would make more sense to me. Mt MTBs I run 27-28" wide bars, this helps opens your lungs and slows down the steering for more control.

his bike i s a 26" MTB, smallest tires he can get are like 1.5" slicks
__________________
Rule #10 // It never gets easier, you just go faster.
jsigone is offline   Reply With Quote
Old 12-19-12, 01:59 PM   #6
fietsbob 
coprolite
 
fietsbob's Avatar
 
Join Date: Jun 2010
Location: NW,Oregon Coast
Bikes: 7
Posts: 18,086
The axle center to fork crown-race seat distance is what a suspension corrected fork is meant to maintain.

That retains the Head angle..

Measure and compare..
fietsbob is offline   Reply With Quote
Old 12-19-12, 01:59 PM   #7
maidenfan
Senior Member
 
maidenfan's Avatar
 
Join Date: Aug 2006
Location: Portland, Or
Bikes:
Posts: 570
I've run Salsa and Surly steel forks - great products for a decent price.
maidenfan is offline   Reply With Quote
Old 12-19-12, 02:37 PM   #8
tergal
Senior Member
Thread Starter
 
tergal's Avatar
 
Join Date: Nov 2011
Location: Logan, QLD ,Australia
Bikes: Trek 4300
Posts: 790
http://www.wiggle.com.au/surly-instigator-rigid-fork/

I like that one... just have to paint over the surly brand name .


Thoughts ?
tergal is offline   Reply With Quote
Old 12-19-12, 03:00 PM   #9
Arvadaman
Senior Member
 
Join Date: Dec 2008
Bikes:
Posts: 268
Quote:
Originally Posted by tergal View Post
http://www.wiggle.com.au/surly-instigator-rigid-fork/

I like that one... just have to paint over the surly brand name .


Thoughts ?
Looks good to me.

Most of my bike forks are for 26" with 80mm travel so I use the 1x1. If the Instigator is a 26", 100mm travel,
and fits the tires and brakes you want to use, I am sure it will work well for you.

I have had good luck with Surly stuff.
Arvadaman is offline   Reply With Quote
Old 12-19-12, 03:16 PM   #10
sstorkel
Senior Member
 
Join Date: Apr 2008
Bikes: Cervelo RS, Specialized Stumpjumper FSR Pro, Schwinn Typhoon, Nashbar touring, custom steel MTB
Posts: 5,416
Quote:
Originally Posted by jsigone View Post
Most MTBs are designed to handle either 80 TO 100mm forks. Swapping out 1* of head angle is like going down hill vs going up hill seating possition. It shouldn't make the front twitchy.
And yet, installing a fork that was 40mm longer magically cured all of the bike's handling problems! I no longer have the CAD files used when laying out the frame, which I built myself under the guidance of a master frame builder, but I have to wonder if your 1-degree calculation is correct...

Quote:
Twitchy fronts comes from handlebars being to narrow and following the shoulder movements faster.
That is one possible explanation, among many. Steepening the steering angle, reducing trail, or putting more weight on the front tire (all three of which happen when the axle to crown race distance is reduced) can also cause problems.

Quote:
his bike i s a 26" MTB, smallest tires he can get are like 1.5" slicks
I'm sure that any of the readily available 26x1.0 or 26x1.25 tires would also fit. In my experience, 26x1.5 works well with an aluminum fork.
sstorkel is offline   Reply With Quote
Old 12-19-12, 03:21 PM   #11
tergal
Senior Member
Thread Starter
 
tergal's Avatar
 
Join Date: Nov 2011
Location: Logan, QLD ,Australia
Bikes: Trek 4300
Posts: 790
Actually I run 1.75s but will be ordering 26x1.5

http://www.chainreactioncycles.com/M...?ModelID=24542

That Surly Fork supports 2.7 tyre, and disc brakes.

Unless someone can point out a flaw i think i will order one next pay

hmm wonder if I can use this as a excuse to replace my handlebars
tergal is offline   Reply With Quote
Old 12-19-12, 03:36 PM   #12
sstorkel
Senior Member
 
Join Date: Apr 2008
Bikes: Cervelo RS, Specialized Stumpjumper FSR Pro, Schwinn Typhoon, Nashbar touring, custom steel MTB
Posts: 5,416
Quote:
Originally Posted by tergal View Post
http://www.wiggle.com.au/surly-instigator-rigid-fork/

I like that one... just have to paint over the surly brand name .


Thoughts ?
I own one. It's a good fork given the price. On mine, the Surly branding is done with stickers. You might be able to remove the branding without needing to repaint...
sstorkel is offline   Reply With Quote
Old 12-19-12, 03:38 PM   #13
tergal
Senior Member
Thread Starter
 
tergal's Avatar
 
Join Date: Nov 2011
Location: Logan, QLD ,Australia
Bikes: Trek 4300
Posts: 790
Quote:
Originally Posted by sstorkel View Post
I own one. It's a good fork given the price. On mine, the Surly branding is done with stickers. You might be able to remove the branding without needing to repaint...
Great, was that or find some mud puddles on the road to ride though everyday
tergal is offline   Reply With Quote
Old 12-19-12, 03:39 PM   #14
sstorkel
Senior Member
 
Join Date: Apr 2008
Bikes: Cervelo RS, Specialized Stumpjumper FSR Pro, Schwinn Typhoon, Nashbar touring, custom steel MTB
Posts: 5,416
Quote:
Originally Posted by fietsbob View Post
The axle center to fork crown-race seat distance is what a suspension corrected fork is meant to maintain.

That retains the Head angle..
Not necessarily. Like many things in the bike industry, there's no standard on what the axle to crown-race distance should be for a given suspension fork. Does "100mm of travel" mean 100mm of travel with a 26x1.5" tire installed or 100mm of travel with a 26x2.7" tire installed? Depending on how much tire clearance the fork designer wants to allow the length of the fork can change, sometimes dramatically so. For this reason, you always want to know the axle to crown race distance of the original fork and the replacement before buying. Trust me: I've learned this the hard way!
sstorkel is offline   Reply With Quote
Old 12-19-12, 09:42 PM   #15
tergal
Senior Member
Thread Starter
 
tergal's Avatar
 
Join Date: Nov 2011
Location: Logan, QLD ,Australia
Bikes: Trek 4300
Posts: 790
Thanks for all your help.

Fork added to X-mass shopping list.

o/
Tergal
tergal is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 05:21 PM.