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


Go Back   > >

Bicycle Mechanics Broken bottom bracket? Tacoed wheel? If you're having problems with your bicycle, or just need help fixing a flat, drop in here for the latest on bicycle mechanics & bicycle maintenance.

User Tag List

Reply
 
Thread Tools Search this Thread
Old 09-23-11, 03:17 AM   #1
Slaninar
Bike Gremlin
Thread Starter
 
Slaninar's Avatar
 
Join Date: Nov 2010
Location: Novi Sad
Bikes: Custom made on Scott Speedster frame, Custom made on a 1996. steel MTB frame (all but frame changed at least once in the past 20 years).
Posts: 2,115
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Conversion to stiff from suspended front

I have a bike with front suspension. Here is the pic:



Uploaded with ImageShack.us

Considering geometry of this bike, do you think it would be OK to change the front suspension for a pair of normal, stiff, forks? I hate suspension.

The bike is used for a 7 mile commute to work (and 7-10 miles back) all year round.
Slaninar is offline   Reply With Quote
Old 09-23-11, 05:36 AM   #2
goatalope
Biking Viking.
 
goatalope's Avatar
 
Join Date: Nov 2007
Location: Camp Hill, PA
Bikes: '01 Lemond Buenos Aires, '11 Specialized Stumpjumper FSR, 70s Austro Daimler Inter 10, 80s Motobecane Mirage 10 Fixed Gear
Posts: 317
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Yeah, it would be fine. You just need to find a fork adjusted for suspension. Measure from the axle to the crown and try to find a rigid fork with a similar length. Only trick might be finding a threaded fork these days.
goatalope is offline   Reply With Quote
Old 09-23-11, 05:45 AM   #3
dabac
Senior Member
 
Join Date: Mar 2008
Bikes:
Posts: 5,360
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Quote:
Originally Posted by goatalope View Post
Yeah, it would be fine. You just need to find a fork adjusted for suspension. Measure from the axle to the crown and try to find a rigid fork with a similar length. Only trick might be finding a threaded fork these days.
+1 on the above. When you measure axle-to-crown, do it with weight on the bike as it's the normal ride compression length you want to mimic to keep the handling as before. It doesn't have to be spot on.

Quote:
Originally Posted by goatalope View Post
.. Only trick might be finding a threaded fork these days.
+1 again. You might want to consider switching to threadless headset (and a new stem) while you're at it.
There are various workarounds that sometimes allow you to use a quill stem in a threadless fork, but I'd just go for the replacement instead.
dabac is offline   Reply With Quote
Old 09-23-11, 01:19 PM   #4
robert schlatte
Senior Member
 
robert schlatte's Avatar
 
Join Date: Dec 2007
Location: columbus, ohio
Bikes: Soma Saga, 1980 Schwinn Voyageur 11.8
Posts: 650
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 2 Post(s)
I did the same thing with my mountain bike. I took the crown race off the suspension fork and re-used it on the rigid fork. Mine was threadless so a had to cut the steerer tube and install a new star nut. The conversion was fun and easy. In your case, I checked on line parts suppliers, and there are threaded forks available for 26" mountain bikes. Good luck.
robert schlatte is offline   Reply With Quote
Old 09-24-11, 01:43 AM   #5
Slaninar
Bike Gremlin
Thread Starter
 
Slaninar's Avatar
 
Join Date: Nov 2010
Location: Novi Sad
Bikes: Custom made on Scott Speedster frame, Custom made on a 1996. steel MTB frame (all but frame changed at least once in the past 20 years).
Posts: 2,115
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Thanks for help. I measured compressed forks. From bottom (axle) to the part where they come inside the frame, it is about 18-18,5 inches. However, all the bike shops I went to (3 so far) convinced me that I can't find forks that long and that frame is made for suspension. Bollox?
Slaninar is offline   Reply With Quote
Old 09-24-11, 03:14 AM   #6
dabac
Senior Member
 
Join Date: Mar 2008
Bikes:
Posts: 5,360
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Quote:
Originally Posted by Slaninar View Post
....I measured compressed forks. From bottom (axle) to the part where they come inside the frame, it is about 18-18,5 inches.
So about 460 mm.

Quote:
Originally Posted by Slaninar View Post
.... However, all the bike shops I went to (3 so far) convinced me that I can't find forks that long...
I really doubt that.

Does the bike have 26" or 29" wheels?

If it's a 29er/hybrid I had no trouble at all finding a rigid fork with a fitting length.

If it's a 26" I reckon a rigid fork suspension corrected for 100 mm travel should be a decent fit. Didn't find one of those as easily though.
If you're willing to switch to disc brake front as well, you can certainly get away with using a 29er front fork and a 26" wheel.


Quote:
Originally Posted by Slaninar View Post
...... all the bike shops I went to ..convinced me that .. frame is made for suspension.
Well, sure it is. But I'm betting there's a sus-corrected fork that'd fit it anyhow.
Rigid forks with 430 mm axle-to-crown are easily available. It'd be a bit of a drop, but IMO not enough to render the bike unrideable.
dabac is offline   Reply With Quote
Old 09-24-11, 05:01 AM   #7
Slaninar
Bike Gremlin
Thread Starter
 
Slaninar's Avatar
 
Join Date: Nov 2010
Location: Novi Sad
Bikes: Custom made on Scott Speedster frame, Custom made on a 1996. steel MTB frame (all but frame changed at least once in the past 20 years).
Posts: 2,115
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Quote:
Originally Posted by dabac View Post

So about 460 mm.

Does the bike have 26" or 29" wheels?

If it's a 29er/hybrid I had no trouble at all finding a rigid fork with a fitting length.
Yes, 460 mm. It has the big wheels, bigger than mountain bikes. I thought it is 28". Like 700 tyre (has written 700 x 38 C, or like 40 X 622).

Quote:
Originally Posted by dabac View Post
Well, sure it is. But I'm betting there's a sus-corrected fork that'd fit it anyhow.
Rigid forks with 430 mm axle-to-crown are easily available. It'd be a bit of a drop, but IMO not enough to render the bike unrideable.
If 430 is standard, it isn't that much shorter than this setup, I think. I figure going to a bike shop and asking for 460 mm rigid for for 28" (or 29"?) tyre bike, with normal (v-brake) brakes would be the righ thing to do? If there aren't any such, I'll try 430 ones.


I mean, is it just me or this supended bike seems like the old stiff forked with an under inflated tyre? It sort of goes less fast.
Slaninar is offline   Reply With Quote
Old 09-24-11, 05:23 AM   #8
dabac
Senior Member
 
Join Date: Mar 2008
Bikes:
Posts: 5,360
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 8 Post(s)
Quote:
Originally Posted by Slaninar View Post
Yes, 460 mm. It has the big wheels, bigger than mountain bikes. I thought it is 28". Like 700 tyre (has written 700 x 38 C, or like 40 X 622)..
Well, that is the size currently labeled as 29er, for reasons too arcane for anyone outside the marketing guild to understand. Basically it's the same as the 28" AKA 700C AKA 622 mm road standard, but designed to be a bit more rugged.

Quote:
Originally Posted by Slaninar View Post
If 430 is standard, it isn't that much shorter than this setup, I think. ... I'll try 430 ones.
It'd be entirely rideable. But some people claim to be very sensitive to these changes, while others (like me), aren't bothered at all. If you want to stay with rim brakes, you have to get the right fork for the wheel size - otherwise the brake pads won't reach the rim anymore.

Quote:
Originally Posted by Slaninar View Post
If 430 is standard, it isn't that much shorter than this setup, I think. I figure going to a bike shop and asking for 460 mm rigid for for 28" (or 29"?) tyre bike, with normal (v-brake) brakes would be the righ thing to do?
You can do better than that. Ask for one of these:

Well, or any other fork of similar dimensions.

Quote:
Originally Posted by Slaninar View Post
I mean, is it just me or this supended bike seems like the old stiff forked with an under inflated tyre? It sort of goes less fast.
Oh, sure. Suspension works by soaking up energy, and as it's really hard to separate the bounce introduced by the rider from the bounce introduced by uneven ground - so suspension will steal some energy from the rider.
What merits the use of suspension is that eventually there is a point where a rider will lose more energy by compensating for bumps manually than he'll lose by pedalling.

Last edited by dabac; 09-24-11 at 05:28 AM.
dabac is offline   Reply With Quote
Old 09-24-11, 06:06 AM   #9
JonathanGennick 
Senior Member
 
JonathanGennick's Avatar
 
Join Date: Apr 2007
Location: Munising, Michigan, USA
Bikes: Gary Fisher Hodgepodge 26er Rigid
Posts: 2,500
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Deleted this post. Sorry. Wrote the whole thing thinking the OP had a 26er, when that's not the case.
JonathanGennick is offline   Reply With Quote
Old 09-28-11, 11:16 PM   #10
Slaninar
Bike Gremlin
Thread Starter
 
Slaninar's Avatar
 
Join Date: Nov 2010
Location: Novi Sad
Bikes: Custom made on Scott Speedster frame, Custom made on a 1996. steel MTB frame (all but frame changed at least once in the past 20 years).
Posts: 2,115
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 20 Post(s)
Thank you again for advice. Now I know what to look for. 430mm rigid forks are the longest I could find. My compressed suspension is around 460-470 mm. Still not sure if the difference is too big. If I don't find longer forks in a week or two, I'll probably go for the 430 ones. Or, considering appaling quality of Serbian roads, get a better shock (with a lock option).

Last edited by Slaninar; 09-29-11 at 09:04 AM.
Slaninar 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 05:56 AM.