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reason for adjustable/replaceable rear dropouts?(12 posts)

reason for adjustable/replaceable rear dropouts?kenyee
Nov 29, 2001 1:35 PM
ok, I thought this was just a quirk w/ the Gios Compact Pro frame, but in the latest Excel Sports catalog, I noticed that Look frames also have this "feature". They list this as a feature used to tune handling, but they don't show alternative dropouts to swap in. Excel hasn't answered email about it. I can't find anything on the Look and Gios sites that describe how to "tune" it. All I've found on the net is that it's useful for MTBs because the dropout usually gets trashed on a crash.
Two separate things.MrCelloBoy
Nov 29, 2001 1:57 PM
Replaceable dropouts are just that. Typically on Aluminum frames, they allow replacement of just the dropout if oune gets damaged or bent.
Adjustable dropouts have a set screw adjustment that typically allows about 2cm of adjusment to the wheelbase of the bike. This would affect the overall handling. In basic terms short=quicker handling, long=more stable.
you're talking about derailleur hangersJack S
Nov 29, 2001 2:06 PM
Looks do indeed have adjustables, but the travel is short. I'm not aware of any that have 2cm of adjustment.
hogwashJack S
Nov 29, 2001 2:04 PM
There is rarely enough adjustment to make a significant difference in ride. The only reason I can see would be for clearance of bigger tires.
re: reason for adjustable/replaceable rear dropouts?bikedodger
Nov 29, 2001 2:17 PM
I found this picture of the "GIOS patented investment casting rear fork-ends" on their web site. Looks adjustable, but not much. I can understand the replaceablity for the derailer hanger, but I don't know what the advantage of the adjustablity would be.

Mike
re: reason for adjustable/replaceable rear dropouts?Lone Gunman
Nov 29, 2001 4:33 PM
Adjustable dropouts are supposed to shorten the rear wheelbase by making the rear chainstay shorter and the tighter triangle gets you a bit closer to a climbing setup. Gimmick? Theory? I have no idea if it works. Never rode one to make a comparison.
The main reasonNessism
Nov 29, 2001 5:22 PM
One main advantage of adjustable horizontal dropouts is they allow you to center your wheel between the chainstays of you break a spoke and the rim pulls to one side. A broken spoke on a frame with vertical drop outs can result in a car ride home.
Speaking from experience ...tarwheel
Nov 29, 2001 6:29 PM
I have a Gios Compact Pro with adjustable dropouts. With the dropouts moved all the way forward, the chainstay length is about 40 cm, which is quite short. I moved mine all the way out shortly after I got the bike because I prefer a smoother ride, which supposedly you get with longer stays. With the dropouts fully extended, the chainstay length is increased about 1.5 cm. To be honest, though, I didn't notice much difference in handling after moving the dropouts, although the ride did seem a little smoother. To me, the main advantage of the Gios dropouts is that they are easily replaceable if they ever get damaged. It would be a useful feature, as well, if you used a Gios frame to build a single-speed or fixed gear bike because you could adjust the chain tension that way.
Are you sure it's really 1.5cm?kenyee
Nov 29, 2001 7:38 PM
Someone below looked at the picture and said it looks like it can move only .5 cm at most.

Also, the Look can only be changed a tiny bit. Here's there reply to my inquiry (I'm impressed...only took a few hours for them to reply :-)

Ken, thanks for the inquiry. The adjustment is 6mm fore/aft. Both right and
left dropouts come set up in the middle and can be brought forward 3mm or
back 3mm. It does work for climbing or a full flat road race. They are
adjustable via 2 allen bolts on each dropout.

Rob "Wizz" Whisenhant
Veltec Sports Inc.
Northern & Central California Inside Sales
Email Tech Support
877- 874 - 2849
Wizz@veltecsports.com

-----Original Message-----

I have a quick question on your look frames. Some of them mention:
"Adjustable hangers : Modified wheel base" (from the French site).
How much can the wheel base actually be changed? I haven't found any
replaceable dropouts to swap with in any catalogs. Does this actually make
a difference?
It seems like a gimmickcrankset
Nov 30, 2001 10:03 AM
It seems like something else to go wrong on the bike. I like to keep things simple and adjustable dropouts in my opinion is just asking for trouble. There was a thread somewhere else about people complaining about these dropouts moving even when tight. And the bolts they use are pretty small; get one too tight, strip it and you have a big problem in your hands. Replaceable derailleur hangers make sense and they just fit one way so there,s no chance of them moving around.
have seen them up closeColnagoFE
Nov 30, 2001 10:42 AM
At excel sports...The shop guy said they always adjust them as far from the frame as possible as when they are too close people have gotten road debris and sticks and the like lodged between the frame and the rear tire. Don't really know why this would be a desirable feature on a bike.
Having owned several LOOK framesCT1
Nov 30, 2001 5:00 PM
IMHO, this is mainly an ease of manufacturing issue. Allows them to adjust out tiny alignment variations.

Of course, someone will probably cry foul over this but do I care... LOL

YMMV
JohnG