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pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 12:49am
by Brucey
The very first book (that was any use) I ever read on bicycle maintenance had a whole chapter on pedals, despite being a relatively slim volume. This was surprising in that there were not that many types of (half-decent) pedal in common use; they pretty much all had adjustable ball bearings, no seals, and things such as clipless pedals had yet to be dreamt of. IIRC the chapter started (from memory) roughly thusly;

...pedals live hard, dissolute lives, in an oft-forgotten and neglected part of the bicycle, where they see the least maintenance and the worst conditions, being showered liberally in the muck that comes off the front wheel....


-or words to that effect. It is probably as true now as it was then, fifty odd years ago. The difference is perhaps that today, half decent pedals can be bought very cheaply; so cheaply in fact that folk tend to neglect them and then chuck them away when they go wrong, rather than to maintain them and/or repair them. This is a shame because many inexpensive pedals are actually far better made than budget pedals used to be. Years ago, cheap pedals (eg 'Union' ones) had non-adjustable ball bearings (which were often slack from day one), and spindles that quite often bent or just broke. They really were not very good. If you were lucky enough to have a set of adjustable pedals, chances are that they had pressed steel bodies, assembled by riveting (that often worked loose) and/or a feeble tab washer inside the pedal, that fitted a single tab into a narrow, stress raising groove in the pedal spindle. Often the tab on the tab washer didn't survive the first adjustment without failing.

By contrast today's cheap pedals usually have very strong CrMo spindles (when was the last time you saw one break?) and the tab washer is usually built like the ones in the very excellent MKS pedals, even if the pedals in question are cheaper than that. The pedal spindles have a smaller stress-raiser in them, and the tab washer works better too.

IMHO the best kind of budget pedals to buy are ones with adjustable cup and cone bearings; be wary of those which say 'sealed bearings' and/or 'cartridge bearings' especially if the pedal bodies are appealingly slim; both statements may be true but the bulk of the load may be borne by a thing called 'a DU bushing' which is cheap, nasty, high in friction, and potentially rather short lived. So what to look for when buying inexpensive pedals with cup and cone bearings?

There are pedals with a plastic body; these are best avoided. You don't have to spend much to get ones with a cast aluminium body; into this the cups are set. Avoid the ones that are cheaply made and have very slim bodies; if they do have cup and cone bearings they may be rather undersized ones. it is possible to make good pedal bearings with tiny parts in them (eg Shimano SPDs etc) but these are an exception. Typically in 'normal' pedals the spindles use 1/8" or 5/32" ball bearings and the cups are usually about 20mm OD or 22mm OD depending on the ball size used. the cups are the same OD at each end of the pedal but have a different bore size, so that balls cannot escape through the centre hole, given that the spindle is tapered. 5/32" balls make for a stronger (and lower friction) bearing than 1/8" ones, but if kept adjusted and lubricated properly, either can give a smooth and reliable bearing.

Dustcaps are either pressed into a recess (and need to be pried out) or are screwed into position. Plastic dustcaps which are smooth on the outside are almost invariably pressed into place. Removal of the dustcap usually presents this kind of view;

Image

Which comprises a locknut (11, 12 or 13mm usually, for which you will need a full-hex socket, ideally) behind which there is a tab washer and a cone which has the bearing surface on it, and behind that you can see the balls (12 of them in this case). The tab washer bears against two flats on the spindle and it prevents the cone from turning wholesale as the locknut is loosened/tightened. It should be noted that the tab washer always has some backlash on the spindle; this can make cone adjustments a little hit and miss, until you learn to keep track of whether the tab washer has or has not moved with the cone. The cone is best adjusted by teasing it round using a small screwdriver.

Obviously the locknut pushes the cone down onto the thread flanks, so the correct adjustment is obtained by tightening the cone finger tight, and then backing it off about 1/6th of a turn (to allow for the clearance in the threads). Trial and error from there will get it spot on; the objective is (with the locknut tight) to have no free play and no roughness or binding.

This photo shows the alternative (older type) design ( locknut removed)

Image

with a single tab on the tab washer. This design commonly has less backlash but isn't as strong.

With cheap pedals it isn't a bad idea to check that the correct number of balls is actually installed; quite commonly there is one ball missing in one or more of the four pedal bearings. Each bearing takes approximately 11, 12, or 13 balls, depending on the design. If in doubt, add an extra ball, tighten the cone finger tight and see if the bearing feels nice or bindy. If bindy, and there is no longer any gap visible between the balls, maybe it was one too many.

Obviously the inboard bearing is susceptible to getting water in it. It is also easy enough to lubricate, if there are no seals; the lazy way of keeping on top of this is to simply spray the bearing with an aerosol SFG (or motorcycle chain lube) through the gap. If this is done once every couple of weeks most unsealed pedals will survive the winter OK. Oil works too but it doesn't persist in the same way, so repeat applications are required more often. The outboard bearing is protected by the dustcap but this doesn't entirely prevent corrosion; repacking the bearing with grease every year or two isn't a bad idea. Better yet fit a lube port to the pedal.

Clearly one important factor is the design of the pedal; will your foot slip on it, or be comfortable in the shoes you intend to wear? Might you want to fit toe clips? Are you going to keep the (legally required) reflectors? Are the reflectors liable to be knocked off or are they positioned in a recess in the pedal body?

Another important factor is how the pedal body is put together. There are commonly several different options

1) cast one-piece body
2) cast centre body with wrought cage plates, riveted in position
3) cast centre body with wrought cage plates, screwed in position.

The first of these is OK provided the body is designed to be made that way, i.e. so that there are not too many delicate protrusions that can get knocked off; cast aluminium is usually a lot less ductile than wrought stuff.
The second of these is OK provided the rivets are good and strong. Good rivets are seen on pedals like the MKS sylvan models, and making pedals this way is impossible with poor quality (brittle) cast bodies.
If screws are used to hold the pedal together then the screws need to be strong, well fitting, and properly tight and/or threadlocked. Screws vary from 'thread forming' type to nicely machined screws that fit well into tapped holes and are usually in either M4 or M5 size.

The photo below shows how this can all go horribly wrong;

a dodgy bunch of pedals
a dodgy bunch of pedals


Clockwise from top left they are VP-516A, one-piece Wellgo LU-962, and an unknown pedal with no markings. The last of these had problems from the start with the cage screws backing out, but at least the cage was ductile. The LU-962 RH pedal has had all four cage projections broken off its cast body and then the dustcap was lost; the left pedal somehow survived unscathed. Both these pedals sets had bearings that had never been adjusted or lubricated, and were variously bone dry and/or very loose, but would come good again with a little TLC . The VP pedals have wrought cages held on with (unthreadlocked) screws and may well have suffered the same fate as the no-name pedals in time; however the bearings were set so tightly from new that the pedals were removed from a new bike and unceremoniously hoyed into the LBS scrap bin before they had even done a turn.

Note that the VP pedals don't have a full shoulder on the pedal spindle; this allows more room for a decent sized spanner but it also allows chews the crank up (if a pedal washer is not used) and allows water to penetrate the pedal thread more readily. Such pedals can seize into the crank more easily and there is no such thing as 'too much' anti-seize in the pedal threads; best if you coat both the crank thread and the pedal thread before the parts are assembled; this prevents the anti-seize being wiped off the pedal thread on the way in, leaving none on the backside of the thread.

The above all applies to good/medium quality pedals such as MKS ones, as well as cheaper ones (like Wellgo or VP) that come from Taiwan or China. Even the latter can last well; I had a set of cheap VP ones that I eventually retired (after at least 30000 miles); despite a 'corrosion incident' early in their life they were amongst the smoothest pedals I have ever used by the time they came off the bike, and they hadn't needed any further adjustment for several years, just an occasional squirt of lube through the lube port.

Now it may seem a waste of time, servicing a £10 pair of pedals, but IME this can make them work as well and as reliably as a much more expensive set. In this day and age any re-use and life extension of anything is one tiny act that spares the planet, just a little bit, too.

Re: pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 8:16am
by francovendee
Very interesting Brucey.
I usually don't buy high end stuff and this includes pedals.
The last pair I bought cost less than £10 and were of the flat metal type. We ride on very dusty tracks and after 3 years use and around 15000 miles they had a small amount of play in the bearings.
I decided to take a look inside before deciding whether to buy some new ones.
I was very surprised as to how well they were made and the condition of the cones and cups. Absolutely no signs of pitting.
I've now done a further 5000 miles with them and they haven't got any play. Maybe I'm lucky and don't have to contend with wet salty conditions but cheap stuff isn't always rubbish.

Re: pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 10:47am
by Thornyone
Thanks Brucey, interesting article. I have had some Evans pedals for about 3 months now. They were very smooth and totally without play when I bought them, but have developed a small amount of play since then (done a bit over 2,000 miles on them). Reading your piece, I took the plunge. Removal of the dust-cap (6mm hex screw type) revealed a nut. I tried unscrewing it anti-clockwise (this was the right pedal) but it would not budge, so I thought I would confine myself to adding some extra grease by filling the hollow of the cap and screwing it in*). After doing this a couple of times the “rubber” seal popped out of the crank side of the pedal and the pedal would not rotate. I said “Oh, bother!” (or maybe not :lol: ).

I discovered that the nut would unscrew, clockwise. Pulled the spindle out, cleaned off some of the excess grease, and managed to re-locate the displaced seal and re-assemble the pedal. There now seems to be no play at all and the bearing feels very smooth.

So it is presumably a non-adjustable bearing, and I don’t think I’ll mess with the left pedal, which feels very smooth but with a tiny amount of play.

*In the past I have adjusted ball-bearing type pedals like those you describe but found it so much hassle that I have confined myself to adding extra grease by forcing it in using the dust cap. I have used MKS pedals and find that the dust caps, being of the press-in rather than the screw-in variety, are not easy to pop out and tended to get a bit chewed up.

Re: pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 2:03pm
by colin54
About 5 years ago I swapped over to using flat pedals with pins, I bought a set of Revolution ones from

Edinburgh Bikes, the bloke in the shop told me they were a knock off copy of 'Gusset' pedals (I'd never

heard of them either).I used them for a couple of years and one side developed a bit of play ,so I

stripped it and found it used bushes at both ends of the spindle. I started looking for a replacement set

and found a set of Gusset 'Slim Jim' which looked exactly the same as the Revolution ones, except they

were specced with ball bearings. I bought a set and took them apart to give them a bit of an adjustment

and grease up before use, big mistake.There was no locking washer to enable adjustment, no groove in

the thread to take one either.I tried my best tricks with screwdrivers down the side and thin sockets etc

to adjust them but couldn't do it.Luckily I hadn't stripped the one the same side as the worn existing

pedal.I then rode around on odd but identical looking pedals for a couple of years until the Gusset one

started to giving trouble , possibly not unconnected to the fact it used 12 x 2 rows of tiny 3/32''bearings,

with no form of sealing whatsoever, I ended up putting the old bushed pedal back on which I use to this

day,play and all.The locknut was 10mm and cone 11mm on the Gussets by the way.

The Gusset pedals came with a 'witty' instruction leaflet...a sample from it attached and a sheet of

Gusset stickers.If they'd paid an engineer the money they paid the writers and designers of this tosh

they might have made a decent pedal as they are comfortable in use.

These pedals got a 4.3 star rating on Chain Reaction's site!

I've bought some of the Wellgo V8 copies to use on various bikes and as you've mentioned before Brucey

the main thing that could be improved is the in-board seal as there is quite a large clearance between it

and the spindle for some reason, nice big bearings though, straightforward to adjust and best of all

cheap.
P1100660 (640x389).jpg


P1100661 (640x280).jpg


P1100663 (631x640).jpg


I've always had good service from MKS pedals in the past' nicely made pedals for the money if they suit

your style of riding

.I don't think they do a pinned BMX / MTB type pedal though,or didn't when I last looked.

On the bike I use the most, I splashed out on some Shimano Saints which I've greased regularly but

notice they have started to develop play between the bronze outer of the bearing cartridge and the

pedal body itself somehow, so expensive pedals may not necessarily be the best choice.

If you want some pedals to join your 'dodgy bunch', you would be welcome to these Gussets.

Re: pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 7:46pm
by Brucey
shimano saint pedals PD-MX80 are that rare thing, a pedal with a slim body that has half-decent bearings

http://si.shimano.com/pdfs/ev/EV-PD-MX80-3390A.pdf

Image

They are built the same way as the bearings in SPD pedals. They are adjustable ball bearings, mounted a 'cartridge' arrangement. There is no 'bronze bushing', the coloured part is an anodised aluminium sleeve; in the picture above the ball bearings are in the left side of the cartridge assembly, just like in an SPD pedal. Keep on top of the adjustment and lubrication and they should outlast most of the other parts on your bike.

Regarding the locknut that "wouldn't loosen" in one of the above posts. There are some pedals (with slim bodies) which have adjustable ball bearings (often 12 x 3/32" ones) with no tab washer between the cone and locknut. The reason the locknut won't undo is usually that it is on a left-handed thread, in the RH pedal. Years ago this used to be not uncommon, then died out, then reappeared. in theory the locknut/cone thread ought to be handed in order to resist the effects of precession. Some shimano SPD pedals have a left-threaded locknut/cone in the RH pedal too, but most don't. Most cheap Taiwanese/Chinese pedals (and all MKS ones) which have 1/8" balls or 5/32" balls have right threaded locknuts both sides.

The same (expensive) shimano tool that is required to adjust bearings in PD-M323, PD-M324, PD-M505, PD-M535 etc will often work with the slim bodied pedals which have 3/32" balls in them too. Unfortunately the bearings are made in such a way as once they have a little free play, the load is not shared between balls very well and the rate of wear increases dramatically.

The above explains why I suggest that (with a few exceptions) you avoid pedals with slim bodies; they nearly always have a bearing design that (one way or another) is troublesome.

cheers

Re: pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 8:17pm
by Cunobelin
Worst and most dangerous pedals that I ever had was not that cheap

MKS removable SPDs

Image

I cannot say thatthey were a false description.... they are certainly removable.

You press the small collar and the pedal is released, absolutely fine for the Brompton.

They then provide a small plastic "safety clip" that breaks / falls off in the first mile.

So there I am stopping at traffic lights, and disengage... except instead of the cleat, the whole pedal disengages, and instead of aft sole, you are now trying to balance your foot on an SPD pedal attached to the shoe.

After the third dodgy stop I removed the pedals and put them in teh bin.

Dangerous to say the least and at £90 certainly not cheap

Re: pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 8:31pm
by Brucey
plastic clips are consumables that need to be replaced as they wear/fail/are damaged.

If you want the convenience of removable pedals but with a more robust (and expensive) retention system MKS now do an 'EZY superior' model, with a more robust and secure clutch on it.

cheers

Re: pedal perils; can cheap pedals be any good?

Posted: 16 Sep 2018, 8:37pm
by colin54
Brucey wrote:


They are built the same way as the bearings in SPD pedals. They are adjustable ball bearings, mounted a 'cartridge' arrangement. There is no 'bronze bushing', the coloured part is an anodised aluminium sleeve; in the picture above the ball bearings are in the left side of the cartridge assembly, just like in an SPD pedal. Keep on top of the adjustment and lubrication and they should outlast most of the other parts on your bike.





Thanks Brucey, I'll adjust them up, I've had them apart before, but a while ago, I'd forgotten how they

are constructed since.

Re: pedal perils; can cheap pedals be any good?

Posted: 17 Sep 2018, 4:42am
by MikeDee
Shimano PD-M520 pedals. Bought some for $25 a set. One of the best pedals I've ever used. Have them on multiple bikes. Rarely ever need service. Bearings are adjustable and have true ball bearings (not bushings).

Re: pedal perils; can cheap pedals be any good?

Posted: 17 Sep 2018, 6:23am
by Cunobelin
Brucey wrote:plastic clips are consumables that need to be replaced as they wear/fail/are damaged.

If you want the convenience of removable pedals but with a more robust (and expensive) retention system MKS now do an 'EZY superior' model, with a more robust and secure clutch on it.

cheers


Twice daily?

Re: pedal perils; can cheap pedals be any good?

Posted: 17 Sep 2018, 7:58am
by Brucey
see
http://www.elessarbicycle.it/mks-pedals-with-ezy-and-ezy-s-review/

for a comparison of the new and old EZY systems. I suspect that in the SPD-esque pedal, if you have shoes with a wide sole, they can perhaps (especially if the foot tilts at all as you are doing it) push the collar inwards when you go to release. This can also happen with the flat pedals that use the same release design.

However that this does not happen with all users is clear from the review above, in which he describes using the clipless pedals without the plastic collars fitted and that he found it 'virtually impossible' to push the release accidentally. Needless to say if the pedals are not correctly fitted in the first place, they can come out without the collar being moved at all.

However if accidental release is a persistent problem (and it must have been common enough else MKS would not have revised the design) then it may be possible revise your shoes (to prevent collar contact) or to do something different to that, eg

- use an O ring to impede the collar movement or
- use a zip tie to prevent collar movement (just cut it off when you want to release the collar) or
- use a re-usable zip tie to secure the collar, or
- use a short length of skinny inner tube to impede the collar movement

There are probably other ways too.

BTW I only mentioned MKS pedals because their basic designs for standard flat pedal bearings/cones/locknuts are those which have been widely copied in cheaper pedals. Maybe another thread would be the best place for a discussion of the EZY release system.

cheers

Re: pedal perils; can cheap pedals be any good?

Posted: 17 Sep 2018, 9:23am
by Brucey
FWIW I overhauled the 'dodgy' VP-516A pedals seen in the first post and I found the following things;

- the bearings were adjusted too tightly (so they were binding) but
- the locknuts were nowhere near tight enough, so in use, one pedal would have become looser and the other tighter, through the effects of precession. [This can destroy the bearings.]
- there were the correct number of balls installed, but nowhere near enough grease
- the screws holding the cage plates on were not tight enough (little more than finger-tight) and
- said screws had no threadlock on them, so surely would have fallen out in just a short period of time and
- the dustcaps are quite a loose fit in the pedal body; in service they will probably fall out and be lost.
- the pedal spindles have burrs in exactly the wrong place, so they will chew the cranks up worse than usual.

once set up correctly the pedals span freely, the various screws were threadlocked and (apart from the dustcaps) I think the pedals will work well now.

cheers

Re: pedal perils; can cheap pedals be any good?

Posted: 8 Jan 2020, 1:06pm
by 9494arnold
I have used a small self tapping screw to trap an 'interference fit' dustcap in the past.

Re: pedal perils; can cheap pedals be any good?

Posted: 8 Jan 2020, 1:40pm
by bgnukem
I usually keep the bearings greased by filling the end cap with grease and pushing/screwing into the pedal body. Do this a few times when the pedal is new until grease comes out of the other end of the axle, then occasionally to purge fresh grease through after riding in wet or dirty conditions.

These days I use Wellgo WPD801 clipless pedals but these have removable end caps and the same approach can be used. With the Shimano SPDs it's necessary to remove the whole axle assembly but grease can still be injected into the end of the axle housing and gets forced back through the bearings when the axle assembly is screwed back into the pedal body.

Re: pedal perils; can cheap pedals be any good?

Posted: 8 Jan 2020, 1:47pm
by Brucey
in a similar vein pedals can usually be filled with grease by using thumb pressure (repeatedly) in the (grease filled) dustcap aperture; the amount the thumb 'bulges' by when pressure is applied is enough to force grease through the mechanism.

It is often also possible to make a 'bung' (eg out of a synthetic wine cork) with a hole in it, and use that in combination with a grease-filled syringe to force grease through.

In any event if a pedal is entirely filled with grease, you can expect some to come out of the pedal as soon as it is used. This can make a mighty mess (if it gets on your shoes it can ruin carpets and other flooring) and (often) will force a push-fit dustcap out.

cheers