Is it possible to replace the flat-top pins on flat pedals with ones that have a dome top?

Question

Is it possible to replace the flat-top pins on flat pedals with ones that have a dome top?

I'm finding that SPD pedals are a bad idea — for me. If I make a mistake while trying something new, I'm much more likely to go down with the bike. But unclipped I feel a lot safer, which in turn makes me experiment more.

But if I miss catching a flat pedal at the right moment, and it hits my shin, it's a nasty tear, hence my search for pins that provide grip, but ones that won't rip my skin.

Context

Three years ago I followed the advice of Paul H in a comment: "You seem to underestimate the chaos of technical mountain bike terrain," and chose double-sided SPD pedals for single track mountain biking. I'm now convinced that clipless pedals are the wrong choice while learning. Flat pedals are best. But I have enough scars from past experiments with flat pedals, hence the question.

Clarification (edit)

Wearing MTB-specific shoes when riding with flat MTB pedals is a good idea, but most or all wounds I've had from pedal pins occurred because I was unable to catch a pedal in time, not because I caught the tip of the pedal with the tip of my shoes and slipped. In other words, wearing better shoes is not a solution to this problem. The shape of the pins (or, failing that, protection) is.

Basically I'd like to replace the bolts on an MTB pedal such as the PD-GR500 with pins that have the following elevation and side-view.

Answer 1

You’d have to see what type of pins your pedals use and find suitable replacements. Some thread in from the top, some thread in from the bottom, some are fully threaded vs partially, some have the tool fitting on the top vs bottom… make sure you match all those parameters. An alternative idea is to grind down your existing pins. This may not be possible if for example the tool fitting is at the tip of the pin.

However, I really don’t believe the shape of the pin tip will make any appreciable difference. Maybe a rounded tip won’t break the skin if you just brush your leg against the pedal, but with anything more than that, the forces involved will be enough to impale you regardless of tip shape. Also, consider that over time, grinding your pedals on rocks and stuff will resharpen the pin tips, and so you’ll need to replace or re-round them on an ongoing basis. You may be better off wearing long pants or some kind of shin guards instead.

Answer 2

I completely agree with MaplePanda that domed metal pin is any less likely to do shin damage than a flat top if one were to slip off the pedals. I would be leery, too, of the possibility of less grip a domed pin might provide. Definitely not looking for less grip on a flat pedal.

I ride flat pedals and would say I'm about middle of the road in terms of aggressive riding single track. I enjoy the drops and jumps that aren't completely insane, and it's these features where I've come off the pedals due to poor foot position and less than adequate control coming into the lip of of a jump. In the few instances where that happened, I was far more concerned for my jewels than my shins since the seat is the next stopping point for the body that has only air under its feet.

At any rate, your grip on a flat pedal is chiefly provided by an adequate amount of well placed pins that have a decent amount of height to gain excellent purchase into a rubber sole riding shoe. Other factors like platform size and a nice dished shape are helpful as well, but ultimately it is the pins which make the foot stay in place.

I ride Shimano XT flat pedals with the long, 6mm pins on both sides of the platform. My properly positioned foot is stuck to the pedal as if I were clipped in. Speaking to your concerns specifically, I'll use the XT pedals (PD-M8140 is the Shimano model number) as an example, although there are certainly other flats on the market with similar features I'm gonna relate. The XT flats come with short, 3mm, pins installed. These pins have rounded upper body and in the center is a 2mm hex tool hole. The bottom is an M3 thread that goes into the platform until the flanged part of the upper pin stops at its seat in the platform. So there are your round profile pins. Also provided with the pedals are long pins these also have an M3 thread that terminates at a small flange. Above that the business end, is a 6mm tall, cylindrical pin that has a round, flat top and the hex tool hole at the center.

Both sides of the platform have pins. You could if you wanted have one side short pins and the other side long pins. You could even mix short and long pins on the same side, perhaps installing the short, round ones in the holes along the long edge of the pedal where you'd most likely scrape your shin should you come off the pedals. I, myself, would not prefer the short pins at all for reasons mentioned above, but wanted to alert you to the possibilities.

Overall flat pedals are the best for developing skills on since you need to have good technique to, say, bunny hop. Also the ability to come off the pedals quickly can be comforting, though one easily get stuck on a flat pedal (I've endo'd a few wheelies not being able to get my feet off the flat pedals and having no more leg extension to kick out off of them), and getting unclipped can be lightning fast with experience (both in technique of the clipless system and anticipating trouble).

Answer 3

I presume you are riding of proper shoes designed for flats. If you are on 'street trainers' this would be my first recommendation. While the pins on good flats can do a lot of damage, you should not really be separating that often.

Less aggressive pins, or removal of pins and using fully molded pedals, will lead to more encounters between you shin and the pedals. You may merely reduce scaring only to replace it with bruising of the shin, or worse, more crashes and more damage elsewhere.

Given you appear to be wanting to push your limits (which is awesome), and find clipless unacceptable (completely acceptable), perhaps you need to consider increasing the aggressiveness of you pedals so your feet remain in contact more often. A foot in contact with pedal means no chance of shin to pedal contact (ignoring the undesirable obvious :) ). Another approach while learning is protection, consider shin guards and wearing protective long trousers (hot and sweaty, but that washes off painlessly at the end of ride). This will mean you do not have to compromise your bike setup and riding, and can walk away from "learning opportunities" unscathed and ready for another attempt.

Answer 4

On my flat pedals the pin thread are M4 and I replaced mine with M4x6mm to fasten half-toe clips on them.

The flat pedals should come with a special wrench to remove the pins. Take one pin off or better yet, if you have spare ones, take one to the hardware shop and try to match the pin thread with those in the metal screw isle, taking into consideration the length for your application.

Ask for help if need too. Some shops don't mind opening a packet to test the thread matches your sample. If you don't mind, take the pedal off the bike and take it with you to the hardware shop and that way you can test the thread of the screws.

On the attached image, you can see the packet of black screws I've used.

I suggest you don't replace all pedal pins with round head screws, but just the ones you suspect to be the most like to cause damage to your shin.

My flat pedals are on a commuter bike and I don't have any experience with MTB riding.

I don't know if the half toe-clip idea is appropriate for MTB riding. I would think it could catch on something if up-side-down and through you out of balance.

Having said that, if you want to try it, it's up to your discretion.

I have more photos with other details to share if you are interested.

Hope this helps.