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Old 07-06-17, 04:10 PM   #1
Brian Charles
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How much clearance should you have from the pedal to ground to be safe ?

We bought a tandem bike and the pedal clearance is approximately 1 3/4" from the ground when riding and the pedal hits the ground very easily. What should be a safe clearance from the ground to the pedal ?
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Old 07-06-17, 04:13 PM   #2
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How much clearance should you have from the pedal to ground to be safe ?

We bought a tandem bike and the pedal clearance is approximately 1 3/4" from the ground when riding and the pedal hits the ground very easily. What should be a safe clearance from the ground to the pedal ?
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Old 07-06-17, 04:15 PM   #3
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Originally Posted by Brian Charles View Post
We bought a tandem bike and the pedal clearance is approximately 1 3/4" from the ground when riding and the pedal hits the ground very easily. What should be a safe clearance from the ground to the pedal ?
Pedal clearance is 1.75in and it hits the ground easily.

Colour me confused?????

It either is 1.75in or it isn't?????
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Old 07-06-17, 04:18 PM   #4
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Inside pedal up whenever you corner.
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Old 07-06-17, 04:42 PM   #5
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Pedal clearance reply

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Originally Posted by acidfast7 View Post
Pedal clearance is 1.75in and it hits the ground easily.

Colour me confused?????

It either is 1.75in or it isn't?????


I presently have 1.75" clearance from the ground to the pedal. Needless to say you can't even casually turn and some times the pedal hits the ground when pedalling in areas where there are bumps, we have to be careful going over the standard round curb or the pedal hits the ground. Schwin is telling me there is nothing wrong with the bike even though the front fork is bottomed out when we ride our tandem bike.
It's not a weight issue as we weigh 195 & 135. How much clearance does the standard bike pedal have from the ground ?
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Old 07-06-17, 05:09 PM   #6
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Originally Posted by Brian Charles View Post
I presently have 1.75" clearance from the ground to the pedal. Needless to say you can't even casually turn and some times the pedal hits the ground when pedalling in areas where there are bumps, we have to be careful going over the standard round curb or the pedal hits the ground. Schwin is telling me there is nothing wrong with the bike even though the front fork is bottomed out when we ride our tandem bike.
It's not a weight issue as we weigh 195 & 135. How much clearance does the standard bike pedal have from the ground ?
1. Don't pedal around corners.
2. Don't ride over curbs unless the pedals are parallel.
3. Get a better fork.
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Old 07-06-17, 05:12 PM   #7
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Sure sounds like a problem. Mine is about 3 1/4"

I'm no bike expert but it sounds way too close, like your wheels are not the correct size.

What bike is it?
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Old 07-06-17, 05:16 PM   #8
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Honestly, this is a weird thread ... Either one gets pedal strike from a ****tly fitted bike or not.

Is this worth debate as I don't want to acquisition 1000fps cameras to determine what is optimal as it must already be in the literature, surely????
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Old 07-06-17, 05:17 PM   #9
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A standard road bike (700 x 23mm) has a diameter of 668mm (334mm radius), and a bottom bracket drop of 78mm, and 172.5mm cranks.
So 334-78-172.5 = 83.5mm = 3.2in which is much higher than your numbers...
My road bike has approximately 3.5in which is consistent.

1.75in seems very low, are you measuring correctly (pedal level)?
What type of pedals?

The front fork being bottomed out isn't particularly surprising. It's probably a standard coil fork designed for a ~200 lbs rider not a tandem. What is the model of fork.
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Old 07-06-17, 07:06 PM   #10
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On my wife's hybrid. it's about 4" from ground to pedal axle center and it's about 6" from ground to the pedal axle center of the stoker crank of our recumbent tandem. (Captain's crank is much higher on this bike.)
What kind of tandem do you have and are the wheels the original size? Stock crank size/s?
Pedal/ground strikes should be rare events and easily avoided.
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Old 07-06-17, 09:35 PM   #11
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I was overcome by curiosity and measured the pedal clearance on my rando bike just now. It's about 3.75".

I agree that 1.75" sounds way low, and even if nothing is technically wrong with your fork, it's not the right one if it is completely bottomed out whenever both of you are on it.
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Old 07-06-17, 10:21 PM   #12
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My Raleigh Competition has 2 1/2". I call it the slinky. (My other bikes have far more.) I hit the pedals regularly. Now it was designed for 27" wheels and I am running 700c, currently with 28c tires. I also run 175 cranks and SPD MTB pedals.

What kind of bike is your tandem? Is the fork original? The wheels? What cranks and what pedals are you running? (Pedal depths and widths vary over an almost incredibly range and can make a huge difference in lean angle before striking,

Somebody at Schwinn should know the design distance for the fork, dropouts to fork crown with your weight on it.

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Old 07-06-17, 11:49 PM   #13
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Quote:
Originally Posted by Brian Charles View Post
We bought a tandem bike and the pedal clearance is approximately 1 3/4" from the ground when riding and the pedal hits the ground very easily. What should be a safe clearance from the ground to the pedal ?
Minimum standards required by CPSC is that nothing touches the ground when the bike is at a 25° lean with pedals in the lowest position. This doesn't necessarily determine the exact height as the pedal length and shape plays a role.
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Old 07-07-17, 08:58 AM   #14
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I put larger, wider pedals on my touring bike, and took my 40mm tires off and put 25mm tires on. I now have to be pretty conscious of pedal strike. But I'm SURE I have more than 1.75 inches of clearance. I'd do something about it if I were you...Wheels or tires, or the fork. Something needs to change.
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Old 07-07-17, 10:12 AM   #15
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I have a tandem with low bottom brackets ( '98 Santana Arriva) and I have to remember to keep the inside pedal up when turning or else we we get pedal scrape. It's good discipline to have on any bike when leaning into turns because you put your weight on the opposite pedal and your butt unweighted which is a low center of gravity and you're ready for bumps.
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Old 07-07-17, 10:25 AM   #16
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Quote:
Originally Posted by Brian Charles View Post
We bought a tandem bike and the pedal clearance is approximately 1 3/4" from the ground when riding and the pedal hits the ground very easily. What should be a safe clearance from the ground to the pedal ?
Something is very wrong here. Maybe a prior owner changed the wheels to smaller ones.

Normal pedal to ground clearance is something between 3 and 4".

The actual distance is less critical than the fact the you report frequent pedal strikes. Occasional strikes when turning is fairly normal, and easily solved by pausing with the inside foot up through the turn.

I don't get how one would get a pedal strike when riding straight, so it's either that you're riding toe down, or possibly the long wheelbase is allowing the bike to beach on humps. But either way, it's not a good thing, and you'll probably want to find a way to raise the BB, either with larger wheels or fatter tires.
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Old 07-07-17, 12:40 PM   #17
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Quote:
Originally Posted by Brian Charles View Post
I presently have 1.75" clearance from the ground to the pedal. Needless to say you can't even casually turn and some times the pedal hits the ground when pedalling in areas where there are bumps, we have to be careful going over the standard round curb or the pedal hits the ground. Schwin is telling me there is nothing wrong with the bike even though the front fork is bottomed out when we ride our tandem bike.
It's not a weight issue as we weigh 195 & 135. How much clearance does the standard bike pedal have from the ground ?
Is this a fixed gear? Or are the two cranksets out of phase? If both of these answers is no, then pedal strike is the result of user error.
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Old 07-07-17, 03:10 PM   #18
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Is this a fixed gear? Or are the two cranksets out of phase? If both of these answers is no, then pedal strike is the result of user error.
That simply isn't true. With 1.75" clearance, you would have to stop pedaling every time there was a speed bump, or significant camber in the road, even in straight line, no turning.
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Old 07-07-17, 06:54 PM   #19
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Old 07-09-17, 10:19 PM   #20
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Sure sounds like a problem. Mine is about 3 1/4"

I'm no bike expert but it sounds way too close, like your wheels are not the correct size.

What bike is it?
It's a brand new 26" Schwinn Twinn Tandem purchased from Amazon sold by Pacific Cycles
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Old 07-09-17, 10:24 PM   #21
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That simply isn't true. With 1.75" clearance, you would have to stop pedaling every time there was a speed bump, or significant camber in the road, even in straight line, no turning.

That's correct, it's a brand new 26" Schwinn Twinn Tandem bike and you have to be extremely careful when riding or you will hit the pedal. It's dangerous, I don't think the front fork is rated or has the capacity for 2 riders.
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Old 07-09-17, 10:29 PM   #22
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Originally Posted by cyccommute View Post
1. Don't pedal around corners.
2. Don't ride over curbs unless the pedals are parallel.
3. Get a better fork.

I'm no expert but I think the front fork isn't rated or have the capacity needed for 2 riders.
It's a brand new 26" Schwinn Twinn Tandem I bought from Amazon sold by Pacific Cycle.

Can I purchase a fork that has higher weight capacity and possibly an inch or 2 taller ?
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Old 07-09-17, 10:36 PM   #23
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Originally Posted by gsa103 View Post
A standard road bike (700 x 23mm) has a diameter of 668mm (334mm radius), and a bottom bracket drop of 78mm, and 172.5mm cranks.
So 334-78-172.5 = 83.5mm = 3.2in which is much higher than your numbers...
My road bike has approximately 3.5in which is consistent.

1.75in seems very low, are you measuring correctly (pedal level)?
What type of pedals?

The front fork being bottomed out isn't particularly surprising. It's probably a standard coil fork designed for a ~200 lbs rider not a tandem. What is the model of fork.

It's a brand new 26" Schwinn Twinn Tandem bike I bought from Amazon sold by Pacific Cycles.
It doesn't have a model # on the fork, it's just the fork the bike comes with and I don't think it has the correct capacity for a Tandem bike.
I'm not really getting anywhere with Pacific Cycle, they sent me a new front fork thinking the one I had could've been defective but it's the same. Now waiting for a response back from Pacific Cycle.
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Old 07-09-17, 10:46 PM   #24
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Minimum standards required by CPSC is that nothing touches the ground when the bike is at a 25° lean with pedals in the lowest position. This doesn't necessarily determine the exact height as the pedal length and shape plays a role.
Thanks for the info. I replied back to Pacific Cycle and am waiting to see if they are going to do anything as they sent me a new fork and there is no change. This is a brand new 26" Schwinn Twinn Tandem I purchased from Amazon sold by Pacific Cycle.
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Old 07-10-17, 10:27 AM   #25
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@Brian Charles The 3.75" number people are quoting is for level ground straight up to center of pedal spindle, it's not really the same thing as clearance. If you measure up from ground to a big platform pedal that's tilted and if the bike isn't perfectly right angle to the ground when you did so, you could easily get under 2"

Pedal strike still shouldn't happen, though. Can you max out the preload in the fork, or lock it out? Or is it not adjustable?

I'd expect the fork on a cheap department store tandem to be pretty bad compared to a Rockshox Pike, but I'd also expect it to be adequately strong and sprung for riding down the road under normal sized Americans.
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