This is exactly how you should not think about it.

You're only confusing me more radical_edward.

I'm just trying to think back to physics class. The total amount of energy is the same either way, but you either spin faster or mash harder. It's the mashing on a high gear ratio that pulls the wheel out. If you put your road bike in the same ratio as your SS/FG, you should experience the same thing with the wheel coming loose.

it's not the gear ratio it's the size of the rear cog. If you use a large cog you move the mechanical advantage to a place where the wheel won't get pulled out.

OH!!!!

You're talking about the distance from the dropout on the plane of the axle!

Ok. Gotcha.

It's funny when people think higher gearing puts more force on the drivetrain just because it's harder to pedal. hahahahah

No I wasn't. I'm not sure there is any lever there.

No but for the same amount of tourque applied to the wheel the one with the smaller cog will put more force on the drive train.

Might be correct if there weren't such a thing as hills. Track riders don't need to deal with hills, that's the main reason they don't have gears.

A heavy tourist on a loaded bike climbing a steep hill puts WAY more stress on the chain than any track rider ever does on the boards.

I think you may be confusing force and work. Work is force times distance. If you lug a 52 tooth chainring at 50 RPM, or spin a 26 tooth at 100 RPM the same amount of work is getting done every second. The rider with the 26 who is spinning twice as fast, is only pushing half as hard on the pedals. The chain can't tell the difference.

However, if the bike is going slow enough that the rider with the 26 is able to lean his/her full weight on the pedal, the pull on the chain will be twice as high.

Sheldon "Physics" Brown

I'm confused, it seems like no one addressed the issue? If so, please correct me.

But it's not apples-to-apples. Compare a derail to a tensioner, both apples.

The springs absorbing the force is the answer, yeah?

Correct. This is a widespread superstition. Good quality quick releases hold as well as nuts, if not better.

See: https://sheldonbrown.com/qr

Does your derailer mount with an adaptor claw like this?


If you removed the adaptor claw with the mangled derailer, the axle stub on the right side may have been long enough to keep the skewer's acorn nut from gripping the dropout...it may have been pressing on the end of the axle. Sometimes removing the coniical spring from the skewer is a quick fix for this.

Sheldon "QR" Brown

RadioFlyer: As far as I'm concerned, the issue is solved.

Sheldon and everyone: I think we're looking at user error here. I have good quality Columbus forged dropouts, a good(?) Campagnolo skewer, and no adaptor claw. I have since put a new derailer on, but before I did I took it out for some serious (single-speed) mashing and it didn't budge a bit.

I don't know what was going on that day: I had the original destruction of the derailer (which I had attributed to bad derailer adjustment, but, in hindsight, may have been caused by a wheel slip) plus one or two slips while in single-speed mode. But given that it hasn't slipped since, I can only assume I wasn't clamping tightly enough.

Is it hard to set a good chain tension and straighten the wheel without being able to loosen one side at a time?

Nope. You just tighten down the QR with one hand and pull the wheel back into the dropout/fork ends and grip down lightly on the QR lever. Once you have the desiered tension (and a centered wheel) you just grip harder on the QR to fully clamp the wheel.

Never had my rear wheel slip on my SS, EVER, when using a steel QR. Had one slip w/ a Salsa ti QR, but those don't have near the clamping force and the aluminum "teeth" don't really grip that well.

I grind up steep hills and never a whimper from the rear wheel..... I can hear my chain groaning, but no slippage.

simple


QR dropouts are fixed position, there is nothing to slide

horizontal dropouts (for adjusting chain slack) can slide, need bolts
or axle stops


no QR will eclipse a grade 8 bolt in tightness
if you tighten the bolt enough. unpossible. qr just cannot do what screw threads can do
for compression force

if you have horizontal dropouts and a qr and it doesn't slip, U are lucky but most peeps need
a surly tuggnut or something similar.

[QUOTE=Sheldon Brown;5297349]Correct. This is a widespread superstition. Good quality quick releases hold as well as nuts, if not better.
See: https://sheldonbrown.com/qr

Mr Brown.
I must preface that you have likely forgotten more about bikes, than I may ever know, but that statement is patently false in regards to my experience.

OFFROAD, I MUST use a tug on my Surly hub and steel track dropouts. The thing would dance with a QR hub on the track ends.

I notice subtle chain tesion variance after several hard backpedals even when using a tug and track nuts.

not trying to be disrepesctful, but my experience is contrary, not a superstition.

I've been losing the proper chain tension repeatedly on my bike (with quick release) during the first few pedals and back pedals immediately after re-setting the rear wheel. I've been periodically re-setting my rear wheel for about 2 months now. Although the slacking chain tension hasn't caused any problems, It just felt sloppy. Today, I'm glad I've finally discovered the problem: The hollow axle can move independently from the acorn nut and skewers; There's wiggle room for the hollow axle; Their centerline do not always align; If the acorn nut is in fixed in a position, it is still possible for the axle to slightly move fore or aft. I don't know if all quick releases are this way.



Previously, I would loosen the quick release and tug on the rim to increase chain tension. This is primarily pulling from the rim to the hub and axle, then the axle pulls the acorn nut and skewers. But this is also moving the axle aft in relation to the acorn nut and skewers. When I begin riding, the acorn nut and skewers doesn't slip on the dropouts (which I thought was the cause of the problem) and do remain where they are but it's the axle, along with the lock nuts, that move slighly forward and would cause the chain to lose tension. That wasn't a problem when the bike had the chain tensioner from the derailleur. I found that the proper way to increase chain tension is not by tugging on the rim but pulling on the acorn nut and skewer instead. This way moves the acon nut and skewers farther back than the axle so that the axle has no more wiggle room to move forward.



I noticed this this morning as I was trying to tighten the chain (again). I tried the newfound method when I got home and I just got back from doing some sprints and immediate slow downs by back pedaling and the chain tension is still how it was.



anyone else with quick release losing chain tension? might want to try this if my explanation even made sense.