bradw

I'm thinking of using these:

https://www.bikescor.com/product/knee.htm

These are little widgets that screw onto the end of your pedal's axles, then you screw them onto the crankarm in the usual way. It moves the pedals out about 3/4" of an inch to increase the Q-factor. I've determined that this is something I want to do.

If you have any experience with these, or know of someone who does, I'd like to hear about it.

Are they reliable? In other words, do they hold up under workload or do they cause crankarm or pedal failure?

Thanks

RacerX

That is stupid. Sorry but that is a dumb product. Most people want narrow Q-factor and if you have knee pain, toe-in usually cures that by taking stress off the knee.

You can toe out but the amount they are advocating is ridiculous and will probably cause injury.

If you still want to blow $50, it's just a simple extender so it shouldn't break. It will increase the leverage on the crankarms so you might get more flex or stress on the bottom bracket and arms but I don't see any problems.

bradw

sorry, rex racer, that wasn't one of the questions.

And out here in the real world, not all people are alike and some people may need a wider q-factor.

Again, does anyone actually have any experience with the product? If you wish to insult me, don't.


BTW - the amount of extension they will provide will make the q-factor on my road bike to be roughly equal to that on my MTB.

late

Hi,
yup, I used a pair with a road bike about ten years ago. I have wide hips, and they seemed to help. They are rugged, and caused no problems I am aware of. If your knees are bowing out; I would say try them.

Raiyn

Wow that's the first time I've seen RacerX shut down so effectively!

RiPHRaPH

but it is also one of those times i actually agree with RacerX. rock on RacerX. I have toe-out syndrome and making conscious effort to decrease Q-factor and have my knees closer to the top tube as i pedal helps my efficiency.

what kind of riding do you do? perhaps RacerX was thinking about this product in the context of all out racing.

RacerX

I wasn't insulting you. I was insulting the product. It is designed without real thought to the mechanics of the knee.
The reason mtb Q factor is wider is for the triple crank. They also try to keep the Q factor on mtb as narrow as possible. If they could make mtb Q factor more narrow, they would.

If you want to equal the Q factor, get a wider bottom bracket. Pulling your feet out to exaggerate a knee problem isn't going to help you, but go ahead and try it if you want. It won't damage your components.

Rotifer

I thought exactly the same thing as RacerX, but decided against posting it. These things are ridiculous. First rule of cycleclub, keep your knees in.

bradw

My concern was with the reliability of the product.

I wouldn't be so quick to assume there is a rule for fit that applies to all people. There are enough threads running right now about how unhappy some people are with the popular bike-fitting methods. I agree with the folks who basically say "Use what works."

Some people seem to be assuming I want to alter the q-factor due to a knee problem. I have no knee problems. I just know that I cycle with less discomfort on my wide Q-factor MTB, even though the angles, reach, saddle height, etc. are about the same on each bike.
The only difference I can find is that the pedals are about 1/2" farther out on each side on the mountain bike than on the road bike, and I really like it that way. It feels like I'm fully using my legs and hips to drive the pedals, not fighting with the pedals like I do on other bikes.

I'm not going to buy the pedal extenders anytime soon. They cost way too much and push the pedals out a little too far.
An archived article on VeloNews by Zinn indicates you can make adjustments with a few washers. I'll make gradual modifications and see how it goes. I know I can't push the pedals out a full 1/2", but there is probably some point around 1/4" that will provide a comfortable fit without compromising the pedal/crank interface.

And I'm just a recreational cyclist. I'll rarely ride more than 100 miles a week.

oscaregg

To add another angle to this, what kind of pedals/shoes do you use? Various kinds have different amounts of lateral adjustment in the cleat ranging from Speedplay Frogs and Time road pedals (none) to Look road pedals (about 6mm.) Also, if you need just a little addition, like 1mm or less, TA pedal washers which were originally made to keep pedals from galling the face of crankarms can add a tiny amount. 2 or 3 TA washers per side would be a safe amount to stack up if you are not using either very cheap or very worn (lots of pedal removal and reinstallation) cranks. That's another thing--the 3/4" addition may turn your pedal into a long enough lever to rip the threads out of a crank made of cheap metal. Everybody does need different "Q" factors, but you are talking about adding an enormous amount so be cautious.

oscaregg

A PS--increasing Q by using a longer bottom bracket will certainly have an effect on your shifting, probably not a good one. Don't do it if you like how your bike shifts now!

bradw

I'm using old-style pedals with clips and straps, and as I stated in my previous posting, I'll be shooting for only about 1/4" of change.

The crankset is a Suntour Superbe. Not too fancy, but looks more than strong enough as long as I leave most of the spindle screwed in.

For such a small amount of change I see no reason to switch bottom brackets.

I'm guessing that hardware store washers will do just fine for this task. If there is some reason why they won't please let me know.

Michel Gagnon

I don't like the idea of using washers to push the pedals out. It may be a good way to try it and see if it works, but having the pedals only partly engaged could lead to premature failure... just when you stand on the pedals.

The main use for pedal extenders is to allow more room for people with ultra-wide feet or those whose ankle hits the crank at each revolution. Some people whose knees always hit the top tube might find a little advantage also. But on the whole, the extenders sound like a bad idea.

Now, if you want a long-term solutions that would widen the pedals just a little bit, there might be another model of pedals that would be a little bit wider.
Finally, there are differences between your two bikes. The geometry of the road bike might entice you to push it harder, and if, as it is most often the case, it doesn't have low gears, you probably push harder when you climb hills. Also, if the saddle is different, you might be sliding more on one bike than on the other. Those little differences might be all that matter in terms of comfort.

Regards,

darelldd

I'm bringing this back from the dead after all these years. Found this while doing some research for my knees. I own five bikes. I can ride the ones with bigger Q longer and more comfortably than the ones with narrow Q. I have blowed legs, and when I stand or run, my feet are naturally farther apart than most other people.

I'm not sure of your biomedical qualifications, but this seems to assume that all people are the same? I have been to three doctors for this (two of the bikers) and every one has suggested that I widen my Q to help solve my knee issues.

Norrower may make for better efficiency. Certainly is it better for aero. It is NOT the best situation for everybody who rides. I don't give a damn about efficiency if I end a ride by sitting with an ice pack on my knee for a couple of days. We don't use our legs the same way for any other sport - and biking is the only sport where our feet are held in place wherever the bike/crank/pedal mfg things they should be held. The Q factor seems to be one of the least-studied aspects of bike fit. And I think that needs to change. People think nothing of chaning the stem length by 5mm. Or even moving the saddle up/down, fore/aft by a few mm's. But move the pedals!? The horror!

jaxgtr

Save some money and check ebay. I found some for $18 and they are stainless steel and solid. I see he now is selling them for $24. They work great, but...if you use clipless and your pedals do not accept a pedal wrench, get your pedals tightened properly can be a bear. Since they are solid, same as the one you ref, you can not use the allen wrench to tighten. I had to get rid of my Look pedals for my CAAD9.

https://cgi.ebay.com/Bicycle-Pedal-Ex...3%3A1|294%3A50


Now, then, I had a need for a wider Q factor and the CAAD9 Q factor was too narrow for me, so I was riding on the outside of my foot and was having massive foot pain. Once I opened the Q factor up a little, 18mm on each side, I was able to put my foot square on the center of the pedal, so while this may be a dumb product to you, it allowed me to ride my road bike in comfort.

esther-L

I have been using kneesavers for 5-6 years. I have had no mechanical problems with them. They are well machined and hold up. I have just the left kneesaver on my commuter bike and our tandem, with Look FQV pedals. I have both kneesavers on my road bike, with speedplay frog pedals.

I have wide hips, and I have a below knee artificial leg. I cannot use clipless pedals without a kneesaver on the artificial leg. My prosthesis would hit the bike frame, otherwise. My prosthetic alignment is very non-textbook.

Kneesavers are not compatible with some crank brothers pedals. The standard pedal wrench does not work on the kneesaver - it needs a slightly larger wrench. I just use an adjustable wrench.

The only thing I disliked about ordering from SCOR was the sheaf of advertising about nutritional products of questionable value that came with the pedal adapters.

darelldd

Thanks for your input, folks! Especially thanks for the Ebay link - I've already ordered more expensive ones, but I figured I wanted two pair anyway.

Panthers007

Shimano Biopace chainrings are said to help people with knee injuries/problems ride with less discomfort - markedly better than round chainrings. Might be worth a shout.

flatlander_48

No, No, No...

Grasshopper should Think Before Speaking.

I have arthritic ankles. One foot is about 10deg out, the other maybe 15deg. When you ride clipless, the distance between the ball of your feet is fixed. Either I twist my knees to force my feet to be closer to being parallel or my heels are almost into the spokes. F+++ Q-factor. It is meaningless for me. The choices are:

• Hurt my knees
• Catch my heels in the spokes
• Ride with flat pedals
• Quit cycling
• Buy KneeSavers extenders or pedal extenders from High Sierra

I have experience with both KneeSavers and the product from High Sierra Cycling. They are essentially the same thing: a chunk of stainless round stock with a male pedal thread on one end, a female on the other and 2 wrench flats.

There is another thread on this issue, to which I also contributed:

https://www.bikeforums.net/fifty-plus-50/370582-knee-saver-pedal-extenders.html

flatlander_48

At question here is how to get your feet into a reasonable position that does not twist your knees; horizontally or vertically. I think the Biopace rings had to do with your leverage on the crank and where it occurred in the pedaling stroke. As far as I can tell, the Biopace rings and pedal extenders work on 2 different issues.

jaxgtr

Oh yea, good point, the ones I got on ebay have this same issue, so people can't steal them with a normal pedal wrench. They are a 19mm wrench size, so I went and bought one to make life easier.

Scor has a fairly easy return policy. I order some and then found the ebay link, so I return the scor version.

flatlander_48

I don't think that is the main reason. Basically it prevents the need to have 2 pedal wrenches if you want to separate the extender from the pedal.

Prabuddhadg

I use toe clips and with one rubber soled shoe which is wide, the inside of the shoe rubs against the crank. So, i have to place my foot hanging out of the outside of the pedal. This extender would be perfect for solving my precise problem.

Neil_B

I use Kneesavers - actually a generic version that costs about a fifth as much - and I love it. I have severely knocked knees, and a right foot turned out 25 degrees. I use them with platform pedals, since there isn't a clipless system with enough float for my joints.

I wouldn't be able to ride a bike without this product.

jaxgtr

True, but a little security is good too.