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 06-22-06, 04:26 PM   #1
ason
Newbie
Thread Starter
 
Join Date: Jun 2006
Bikes:
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
convert from 700 cm to 26 inch mountain wheelset

I recently purchased a cannondale touring bike - and was quite happy with its performance -

one problem - the larger road wheels kept clipping my toes.

I am looking to install 26 inch mountain wheels to rectify the situation, esp when wanting to take some off-road trips.

The only problem i forsee is brake lever compatibility. Cantilevers are currently installed, any way to convert? Or any other small reach cantilevers to purchase?

Also, I am looking to install downtube shifters on the bike as well. But there are no downtube bosses as there were on the older model cannondale tourers! Any way to get a reliable clamp around that fat downtube for 9 speed in the rear? I read campy has a clamp-on 9 speed but will it fit my extra wide tubing?

regards
ason is offline   Reply With Quote
Old 06-22-06, 05:28 PM   #2
broomhandle
Senior Member
 
broomhandle's Avatar
 
Join Date: Dec 2004
Location: Orangevale, CA
Bikes:
Posts: 389
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
can you post some pictures? how old is it? whats the modle number? you can go 650...

http://www.sheldonbrown.com/650b.html
broomhandle is offline   Reply With Quote
Old 06-22-06, 05:35 PM   #3
ason
Newbie
Thread Starter
 
Join Date: Jun 2006
Bikes:
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by broomhandlde
can you post some pictures? how old is it? whats the modle number? you can go 650...

http://www.sheldonbrown.com/650b.html
quite new actually- took a 3 week tour of US, but am looking to for off-road touring -make is cannondale t800- 2005 or 2006.

i want to stay away from weird sizing, but i was just looking at bmx u-brakes- they may go too LOW, as I am looking at a 2.5 inch differential with 26 inch rims.

any ideas on these types of brakes?
ason is offline   Reply With Quote
Old 06-22-06, 05:49 PM   #4
Rincewind8
Radfahrer
 
Rincewind8's Avatar
 
Join Date: Mar 2004
Bikes:
Posts: 656
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by ason
quite new actually- took a 3 week tour of US, but am looking to for off-road touring -make is cannondale t800- 2005 or 2006.

i want to stay away from weird sizing, but i was just looking at bmx u-brakes- they may go too LOW, as I am looking at a 2.5 inch differential with 26 inch rims.

any ideas on these types of brakes?
That is a touring bike, right? Then it probably has a little more tire clearance than a road bike. Maybe some cyclocross tires or 29er tires would do the trick?!
__________________
TH 1.81 (133kg*62)
Rincewind8 is offline   Reply With Quote
Old 06-22-06, 06:05 PM   #5
yes
Senior Member
 
Join Date: Feb 2006
Bikes:
Posts: 675
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Are you putting your feet on the correct part of the pedal? The ball of your feet should go over the spindle. Do you have excessively large feet for the bike size?
Sounds odd to me. You should probably try figuring out why it happens.
yes is offline   Reply With Quote
Old 06-22-06, 06:18 PM   #6
Thor29
Senior Member
 
Thor29's Avatar
 
Join Date: Aug 2005
Bikes:
Posts: 757
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
My guess is that you are riding a smaller sized frame. Toe overlap can be a problem when the frame gets really small and the wheels are the same size. Trying to convert the Cannondale to 26" wheels is not a good idea. First, the bottom bracket will drop, which will cause your pedals to hit the ground when going around corners. Secondly, the brakes won't work. You would be much better off buying a Surly Long Haul Trucker frame, which your local bike shop can order for you - the smaller sizes are built for 26" wheels and it comes with downtube bosses. Just swap the parts from the Cannondale, sell the wheels and frame on Ebay, and buy new wheels. The Surly is a better ride anyway - steel is real!
Thor29 is offline   Reply With Quote
Old 06-22-06, 06:22 PM   #7
ason
Newbie
Thread Starter
 
Join Date: Jun 2006
Bikes:
Posts: 3
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
big feet yes - small wheel handling no

on tour, on u-turns, i nearly fell a number of times - maybe too big feet, maybe poorly designed bike.

mountain wheels would give me more clearance for clean waterbottles and buying power at walmart.

i am looking at those sun ryno rims that never go out of true - so i don't have to worry about the wheel building aspect of bicycle ownership.

at any rate, conceptually, it should be possible to install smaller radius wheels on an american touring bike for off-road riding in the outer reaches of mongolia for example.(making a koga-miyate out of a cannondale) but i perhaps have to play with the wheels in reality instead of trying to figure out sizing and compatibility using little preview pictures of canti v. u-brake brake systems

kind regards.
ason is offline   Reply With Quote
Old 06-22-06, 06:31 PM   #8
Mchaz
Dances a jig.
 
Mchaz's Avatar
 
Join Date: Sep 2005
Location: Central, Ok
Bikes: 2007 Surly Long Haul Trucker 54cm (Commuting/Wanna' go tour so bad), 1985 Trek 670 21" (Road), 2003 Gary Fisher Tassajara 17" (MTB), Cannondale DeltaV 600 (commuterized MTB), some junker bikes in my garage
Posts: 403
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
The easy way to work around the problem is to just be careful when you are making sharp slow turns. I have toe overlap on my road bike, but it doesn't really bother me. If I need to make a turn like that, I will just keep the outside pedal in the farthest back position. 9 o'clock or 6 o'clock position. If you need to pedal during the turn to maintain speed, just do half strokes, never bringing the outside pedal around far enough to hit the tire. Works for me, but YMMV.
Mchaz is offline   Reply With Quote
Old 06-22-06, 06:53 PM   #9
ZachS
\||||||/
 
ZachS's Avatar
 
Join Date: Mar 2006
Location: pdx
Bikes: highly modified specialized crossroads and GT hybrid (really a [formerly] 12-speed bmx cruiser, made before 'hybrid' took on its current meaning), as yet unmodified redline 925, couple of other projects
Posts: 1,360
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
you will not be able to make brakes work easily, unless your frame's set up for discs. what size shoes do you wear, anyway?!?
ZachS is offline   Reply With Quote
Old 06-24-06, 04:35 AM   #10
MichaelW
Senior Member
 
Join Date: Feb 2001
Location: England
Bikes:
Posts: 12,932
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 5 Post(s)
How tall arr you , what size frame and what length cranks?
You can often reduce toe clip overlap (TCO) by switching to shorter cranks ( which may be better suited to your leg length).
On a trail touring bike, TCO is not good. Yes you can avoid overlap by careful pedalling but you are going to flip at some time due to this problem when your mind is full of other problems. TCO is totally avoidable by proper bike designers and as suggested, Surley solve the problem by using proportionate wheels in smaller frames.
The switch from 700c to 26" is not really feasable. You may be able to switch if you have disk brakes but it will also change the bottom bracket height (and pedal cornering clearance)
MichaelW is offline   Reply With Quote
Old 06-24-06, 06:48 AM   #11
Retro Grouch 
Senior Member
 
Retro Grouch's Avatar
 
Join Date: Feb 2004
Location: St Peters, Missouri
Bikes: Catrike 559 I own some others but they don't get ridden very much.
Posts: 26,903
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 206 Post(s)
I can see why you might have toe clearance problems if your bike really has wheels with a 700 centimeter diameter.
Retro Grouch 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 02:36 PM.