Do pedals need to be that tight?

[Pale Rider]

How tight do pedals need to be?

Pedal spanners are generally very long and give lots of leverage.

Handy for trying to undo seized pedals, but I reckon applying a lot of grunt on the pedal spanner when fitting - as most bike shop do - does them up far tighter than needed.

I've just done some pedal changing using my standard length 'garage' spanner.

The pedals I removed must have done a thousand or two miles with no problems.

It didn't take a lot of effort to undo them, but they were still nipped up.

I fitted the new ones with just a firm pull on the same spanner, and from experience, know they will not undo in use.

So why the need to hang off a long spanner when fitting pedals?

 

[ianrauk]

I have never gone crazy with force or hamfisted when putting on pedals. All the ones I have are tightened using Allen key types so unless you have an extended key for extra leverage then they're not going to be done up too tight anyway.

 

[S-Express]

So why the need to hang off a long spanner when fitting pedals?

no need at all

 

[Pale Rider]

I have never gone crazy with force or hamfisted when putting on pedals. All the ones I have are tightened using Allen key types so unless you have an extended key for extra leverage then they're not going to be done up too tight anyway.

Good point, I've never used the allen key type, but as you say it would be impossible to apply a great deal of leverage.

Presumably, the type of pedal makes no difference to required tightness.

Mine are all standard platforms.

 

[Deleted member 26715]

As they should tighten as you pedal then they shouldn't need to be too tight

 

[mjr]

No. Pedalling tightens them. As long as the threads are clean/grit-free and it's not rocking to-and-fro on the threads, I've not had problems. I've had more trouble from gorillas having dug the shoulder of a pedal bolt into its crank so it can never tighten properly again.

 

[midlife]

BITD when I put bikes together for sale the pedals went up pretty tight with a pedal spanner. Last thing we wanted was a pedal to fall off.!!

A bit over the top, my own pedals were put on with just a normal flat spanner

Shaun

 

[Pale Rider]

No. Pedalling tightens them.

I wondered about finger tight and relying on the rotational effect, but I suspect my plodding cadence might not be up to getting that particular job done.

BITD when I put bikes together for sale the pedals went up pretty tight with a pedal spanner. Last thing we wanted was a pedal to fall off.!!

A bit over the top, my own pedals were put on with just a normal flat spanner

Shaun

Exactly what the owner of my local bike shop told me.

He also passed on a good tip.

The left pedal has fine grooves on the spindle so you can tell the difference quickly.

The grooves are just about visible in this pic in which the left pedal is on the, er, right.

 

[midlife]

I wonder if the groove thing is modern?

No sign of them on my fave pedals... Kyokuto Pro Ace... gratuitous pic below

Shaun

 

[MontyVeda]

...
The left pedal has fine grooves on the spindle so you can tell the difference quickly.

The grooves are just about visible in this pic in which the left pedal is on the, er, right.

View attachment 149430

those grooves are so obvious... i've never noticed them before!

 

[Pale Rider]

I wonder if the groove thing is modern?

No sign of them on my fave pedals... Kyokuto Pro Ace... gratuitous pic below

Shaun

Could be a modern thing, or possibly a quality one.

The Kyokutos were/are expensive, so maybe there was an assumption the user would be bike savvy.

 

[alicat]

Isn't the pedal spanner to get them off when they have been on a while with no grease? (damhikt!)

 

[Yellow Saddle]

PR, to give you an exact answer, about 40NM. You can concoct a crow-s foot gadget on your torque wrench or you can just practice on a bolt in a vice, using the same grip length on your testing torque wrench as you would on the pedal spanner.
Pedals have to be tighter than most people think because of the faulty design. Unfortunately we are sitting with a legacy that's hard to reverse.
In engineering terms, just about any left hand thread other than a turnbuckle and some obscure items, a left hand thread is never the solution for things undoing themselves.

When I was a kid my father had an American car, a Valiant. My mom had to do a long trip on her own with just us kids accompanying her. My father showed me how to change a wheel and I had to practice it a few times, including memorising the fact that the left wheels had left hand thread wheel nuts. Today we don't have such wheel nut, they all being right hand thread.
The secret is the taper interface between nut and wheel. A wheel nut/bot is not a flathead. It has a taper under the head that fits into a countersink hole in the wheel rim. This centres the wheel and allows for larger clearances between bolt and rim and eliminates precession, which is the force that undoes bolts like pedals and BBs.

Cranks and pedals should have been designed like that and then we would not have had the problems @mjr reports or, loosening pedals. Powerful riders regularly eat away their crank eyes causing cracks in the crank eye from the stress risers in the gouged-out area.

The way our pedals are currently engineered relies on the pedal axle shoulder resting against the crank resisting the bending force we put onto the pedal. These forces are exactly the same on a car wheel bolt with none of the problems of pedal fixings.

So yes, pedals have to be made disproportionally tight and hence the need for long spanners. Not to mention the poor workshop sod who has to remove overtightened pedals. Godzilla doesn't understand torque.

 

[Yellow Saddle]

You will only find those indicator splines on some cheaper pedals. They are by no means ubiquitous. Some have R and L stamped on them, others rely on a bit of thumbnail threading to give away their handedness.

 

[Pale Rider]

You will only find those indicator splines on some cheaper pedals. They are by no means ubiquitous. Some have R and L stamped on them, others rely on a bit of thumbnail threading to give away their handedness.

Cheaper pedals is about my stamp, so I'm sure you are right.

Maybe I'm imaging this, but I'm sure I saw one set of pedals with compression locking washers.