Modifying MC Pegs for Edirtbike

[DingusMcGee]

It seems to be the consensus that when using edirtbikes on steep difficult terrain foot pegs provide better control than pedals on the cranks.

My first peg installation was just simple a simple add on version.

The pegs are now on one my edirtbikes — simple ones — not the 45 degree break away, yet.

It seems much easier to get far over the handlebars with these foot pegs than the offset standard bike pedals.

I employed a couple methods to stop rotation. Sleeves on end of the spindle are tightened to a part on the bike that does not rotate.



My next prototype was attaching the 45 degree mounted MC pegs to the spindle.


See the StopRotation feature. The tire studs on the pegs make them quite grippy.

I am working on a 45 degree peg mount in which you screw on your pedals of choice. They would be like the high $$$ MC Pivot Pegz.

 

[DingusMcGee]

DanGT86

endless-sphere.com

With his permission from our PM conversations DanGT86 had this useful input:

“It is something I would like to try but its not really an urgent priority.

I think I would likely start with some aluminum plugs that thread into the bottom bracket and put the 14mm threads in like you mentioned. That way I could use standard bike pedals to explore the concept.

Another thought would be to make some bottom bracket mounted plates similar to the ones on cyclone mid drives. You could put a bunch of holes in them and try lots of different peg locations to see which one works best for riding style. Again I think regular bike pedals are the quickest and easiest way to try the pivot concept.

I think motorcycle pegs are the way they are because of stiff moto boots. The small contact area is unpleasant in standard shoes. On a motorcycle we need to be able to pivot the sole of the shoe a lot to operate clutches and brakes. On a bicycle frame based ebike I think good grippy mtb pedals would best compliment my preferred riding shoes.

Seems like some clever dowel pin placement could allow rotation travel limiters.

Some challenges to this idea that come to mind are:
How do I select the proper width similar to a bike Q factor?
How easily would these want to unthread from the bottom bracket?
How necessary is it that they fold up like moto pegs during rock strikes?

The evolution and convergence of heavy ebicyle with light motorcycle is interesting to me. So much of motorcycle and bike design seem to be built for opposite use. Specifically vehicle weight vs rider weight. On a gas dirt bike you typically weigh less than the bike. So you grip the frame/tank with your knees and have a long seat to dynamically move your body about the frame. With a bike you are top heavy and outweigh the bike. So you throw your body around and drag the bike with you without rigidly fixing yourself to it. I feel like this difference makes it hard to know which features like pegs, grips, brake levers need to be carried over to these vehicles we create that are half bicycle half motorcyle.

A good example of this is half twist vs full twist vs thumb throttle. My gas dirt bike is 250lbs. Inertia and big travel keeps it pretty well stable when bouncing over ruts in the trail. I can squeeze the frame with my knees and use way less arm muscle on the bars. My Specialized BigHit 2 ebike with a full twist throttle is way less confidence inspiring on those same trails. It requires a lot more pulling on the bars which is tricky with the full grip twist throttle.

Anyway, I could ramble forever about this stuff. I think I am going to try some 1-3/8-24 BB threaded plugs with 14mm pedal holes first and see how it feels.”

 

[DingusMcGee]

Another person in a talk about MC pegs was

https://endless-sphere.com/sphere/members/bananu7.106180/

To see his experienced commentary see the second page of Myth Busting. The dialogue begins at post 27.

 

[DingusMcGee]

My current question is about peg height.

On an edirtbike what’s the optimal height of the top of the peg platform? Is a mount closer to the seat better than the center of the spindle ( peg platform top location) for navigating steep trail?

My pivot pegz version will likely mount very close to having top of peg(pedal) (45 degree hinged) at the center of the spindle.

 

[bananu7]

I am really liking your practical approach. Instead of just talking, make them and try them out, great!

One more "upgrade" I can offer is that there's a compromise between being able to pivot on the stationary pegs but also get the surface area needed so that your feet don't hurt. Even in MX boots, the small pegs can be quite troublesome during long days where you're mostly standing. Rally-style pegs are more or less the same width but extend outwards more, spreading the load on larger surface area.

On an edirtbike what’s the optimal height of the top of the peg platform? Is a mount closer to the seat better than the center of the spindle ( peg platform top location) for navigating steep trail?

Generally speaking, you want them as low as possible. Most often that will be the lowest point of the frame, as that can come in contact with the obstacles, and you want your boots higher than that. The main reason for that isn't actually for weighing (although it does put rider weight and thus system CoG lower), but the knee bend. It is impractical to make the seat height very tall because that restricts ground access, especially for shorter riders. Instead of the absolute peg height, we often talk about peg-to-seat distance instead, as that's a good indicator of how comfortable you're going to be when sitting down. Check out cycle ergo for some real world examples: Motorcycle Ergonomics

On road motorcycles, the pegs will migrate much higher and towards the back; this allows the rider to push against them during heavy acceleration. Especially in the case of superbike racing, almost all cornerning force comes from countersteering, and the riders will often hang out from the bike to the inside because the turning forces balance out into such extremes.

 

[DingusMcGee]

Pegs Lowered — about 3” — easier to get feet back on pegs. Peg height is now about even with BB spindle retainer bolt hole.

I was able salvage the high MC peg mounts shown earlier in this post. Some grinding needed.






I am waiting for delivery of a piece of small box beam before starting the MC peg mount for the adding of pedals of choice.