queerpunk

The point is that with horizontal dropouts (what you call "FFDOs", but can just be called horizontal dropouts because if they're not horizontal, they're vertical, and if they're rearward facing, then they are not dropouts, they are trackends), there must always be some room between the tire at the most forward wheel position, and the seattube - otherwise you wouldn't be able to get the wheel out without deflating the tire.

with track ends, since you remove the wheel rearward, this isn't necessary. so yes, you can have the most forward position be just a pube hair away from the seat tube. or have seat tube cutouts, for a super short rear end. which many companies have done with sprint bikes.

kyle!

Note a lot road TT bikes have track ends for the reasons stated above.

Gordy748

Having just built my track bike up (pics a-comin') this weekend, I know a little more about this now. Yes, you need a little space for tension and it's very unusual that you would butt the axle right up against the end of the dropout. But often the space is very short, e.g. my Felt TK2 with a 48/16 set up needs to be extremely close to the front of the dropout in order to have the right chain tension. If the dropout was forward facing I wouldn't be able to run this gearing because the dropout would have already ended (else you'd need to dismantle the entire rear hub and extract the axle just to get the wheel out).

Might I add, I got a chain tensioner (mainly because the Felt dropouts are alloy and I heard don't like long term abuse from over tightening the rear wheel nuts) which fits over the rear end of the dropout. Finding the right tension was as easy as turning an allen key, so I would rate this as another advantage RFDOs have.

queerpunk

Track ends. Please, just call them by their name.

carleton

My 2 cents:

The rear-facing track end (not "dropout") is used for multiple reasons:

- If you pull a wheel (apply so much torque that the bolts don't hold the wheel in the frame) during a standing start the wheel won't come off. It will simply cock to one side and lock up.
- Chain tensionsers are used to keep from pulling a wheel (see above), they only work on rear-facing track ends. I can't see how one would work if the ends opened forward.
- Multiple gear combinations require a long track end to keep from using multiple chains.

You don't have to be Chris Hoy to pull a wheel. Here is a young lady doing it:

pstock

"with track ends, since you remove the wheel rearward, this isn't necessary"
and how do you tension the chain?

Nagrom_

words falling on deaf ears.

IvyCap

kyle!

....anddddddd scene.


(Seriously, wiki "bicycle". You've got a lot of catching up to do.)

bitingduck

You haven't done it very much, have you.

carleton

I think we are done here. Closed.