Reverse conversion 700cx to 27 ?
#1
Thread Starter
Newbie
Joined: Aug 2010
Posts: 1
Likes: 0
Reverse conversion 700cx to 27 ?
Hello all- pardon if this has been answered elsewhere...
The time warp situation is that I've wound up with late - 1980s Guerciotti-Alan aluminum cyclocross frame made for 700 c wheels and cantis; and a 27" wheelset from the mid-1970s with high-flange hubs and a five-speed freewheel.
1. The frame has plenty of clearance for the wheels and tires, but it seems like I am compressing the fork and stays when i install the wheels -- could it be the hubs (front is marked Shimano, rear is marked "Sunshine" ) are unsuitably narrow for the frame? (probably shouldn't be stressing the AL fork & stays, eh?)
2. Will most any standard canti brakes be tall enough to reach the rims? or do I need special brakes or something different ?
3. Does anyone know what type of BB threading this frame has? Italian I assume?
Thanks & rgds - Ross
The time warp situation is that I've wound up with late - 1980s Guerciotti-Alan aluminum cyclocross frame made for 700 c wheels and cantis; and a 27" wheelset from the mid-1970s with high-flange hubs and a five-speed freewheel.
1. The frame has plenty of clearance for the wheels and tires, but it seems like I am compressing the fork and stays when i install the wheels -- could it be the hubs (front is marked Shimano, rear is marked "Sunshine" ) are unsuitably narrow for the frame? (probably shouldn't be stressing the AL fork & stays, eh?)
2. Will most any standard canti brakes be tall enough to reach the rims? or do I need special brakes or something different ?
3. Does anyone know what type of BB threading this frame has? Italian I assume?
Thanks & rgds - Ross
Last edited by Ross99x; 08-30-10 at 06:18 AM. Reason: clarity
#2
Senior Member
Joined: Mar 2008
Posts: 8,687
Likes: 301
...late - 1980s Guerciotti-Alan aluminum cyclocross frame made for 700 c wheels and cantis; and a 27" wheelset from the mid-1970s with high-flange hubs and a five-speed freewheel.
1. The frame has plenty of clearance for the wheels and tires, but it seems like I am compressing the fork and stays when i install the wheels -- could it be the hubs (front is marked Shimano, rear is marked "Sunshine" ) are unsuitably narrow for the frame?
1. The frame has plenty of clearance for the wheels and tires, but it seems like I am compressing the fork and stays when i install the wheels -- could it be the hubs (front is marked Shimano, rear is marked "Sunshine" ) are unsuitably narrow for the frame?
Never seen a Shimano front hub be anything but 100 mm. Doesn't mean there isn't one out there though.
That is point of almost religious debate. While it's easy to say that it isn't ideal, it's really hard to say how far from ideal it actually is. Unless too cumbersome to get the wheel to seat properly I'd ride it w/o hesitation.
No way of telling. Generally speaking it seems like frame manufacturers have a fairly relaxed attitude to the standard of where to put brake posts, their position can vary a surprising amount from one bike to another. Unless someone here comes along with experience from that exact frame I doubt if you're going to get anything else than a referral to trial and error and some good luck wishes.
#3
Senior Member
Joined: Jul 2009
Posts: 11,128
Likes: 39
Bikes: 1986 Alan Record Carbonio, 1985 Vitus Plus Carbone 7, 1984 Peugeot PSV, 1972 Line Seeker, 1986(est.) Medici Aerodynamic (Project), 1985(est.) Peugeot PY10FC
Don't take too many chances with stressing aluminum frames. Can't you just trade in/sell those wheels instead and get a wheelset with the proper spacing and dishing? Plus you will have better tire choices in the future with a more modern standard 700C wheelset.
Chombi
Chombi
#4
Senior Member
Joined: Jun 2007
Posts: 12,257
Likes: 5
From: A Coffin Called Earth. or Toronto, ON
Bikes: Bianchi, Miyata, Dahon, Rossin
depending on how wide your rims are, you might not find a single cantilever brake that will work with the height difference.
__________________
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
Food for thought: if you aren't dead by 2050, you and your entire family will be within a few years from starvation. Now that is a cruel gift to leave for your offspring. ;)
https://sanfrancisco.ibtimes.com/arti...ger-photos.htm
Thread
Thread Starter
Forum
Replies
Last Post
jambon
Bicycle Mechanics
12
07-29-18 11:39 PM
woodrupjoe
Classic & Vintage
14
01-22-12 09:48 AM





