Chain slap

[Zambam]

Is it normal for the chain to make a loud slapping noise when going over bumps and the chain hits the chain stay? There are lot's of marks on the paint on the chain stay. Is there an adjustment to get rid of the noise? It's really loud and annoying. I thought the noise may be coming the the center stand so had it removed but the noise is still there.

If the noise is indeed coming from the chain, I am thinking of removing the chain and ride it throttle only. The ebike is nearly 70 lbs and a real dog to pedal. I get plenty of exercise on my 16 lb carbon fiber road bike which is fun to ride and go fast on. I see no point pedaling a heavy ebike if it has a big enough battery and range.

 

[Zambam]

As for removing the chain, I do not see any removable links. Do I need a chain breaker tool? Can you recommend a good but inexpensive one from Amazon? I do not need the best, like Park Tools etc.

 

[Chalo]

The chain won't slap if you're pushing pedals at the time it bounces. But if you don't pedal all the time, and if you can't tolerate chain slap, you could switch to a clutched derailleur and compatible shifter. That's what they're for.

No e-bike in the "slightly above garbage" category will fail to chainslap. They have cheap rudimentary derailleurs and that's just the deal.

Don't shorten the chain if you aren't very sure what you're doing. Just one link too short, and things will break expensively when you shift to the low gear.

 

[Zambam]

The chain won't slap if you're pushing pedals at the time it bounces. But if you don't pedal all the time, and if you can't tolerate chain slap, you could switch to a clutched derailleur and compatible shifter. That's what they're for.

No e-bike in the "slightly above garbage" category will fail to chainslap. They have cheap rudimentary derailleurs and that's just the deal.

Don't shorten the chain if you aren't very sure what you're doing. Just one link too short, and things will break expensively when you shift to the low gear.

It still slaps when I am pedaling going over bumps.

 

[Chalo]

It still slaps when I am pedaling going over bumps.

If the chain is taut because you're pedaling in earnest, it won't slap. If your feet are going around but not pulling the chain, it will slap.

 

[Zambam]

If the chain is taut because you're pedaling in earnest, it won't slap. If your feet are going around but not pulling the chain, it will slap.

I was pedaling hard, chain still slaps over bumps. Could the chain be too long or derailleurs springs shot? How do I test?

 

[Chalo]

I was pedaling hard, chain still slaps over bumps. Could the chain be too long or derailleurs springs shot? How do I test?

In that case, the slap could only be on the bottom run of the chain, so against the underside of the chainstay. Is that what you're getting?

 

[scianiac]

While I think clutched derailleurs are really the optimal solution for a cheaper option you could just install some form of soft chain stay protector. Options here include a wide variety of cheap to cheapish commercial solutions to numerous DIY solutions like wrapping an old inner tube around it.

 

[99t4]

I do see the paint chips on the top of the chainstay in your photo. That chain slap can happen (as others have mentioned) when not pedaling, or when lightly pedaling. If you are actually mashing on the pedals with good force, that top section of chain cannot possibly have enough slack for it to slap down on the chainstay. Picture it in your mind.

 

[Zambam]

In that case, the slap could only be on the bottom run of the chain, so against the underside of the chainstay. Is that what you're getting?

There are wires zip tied to the underside of the chain stay. Wires are not chewed up so the slap is only on the topside. Maybe I wasn't pedaling hard enough? I will wrap some foam on the chain stay tomorrow, go for a test ride and see it the slap is quieter. If so that chain is coming off.

 

[amberwolf]

If you can live without the chain (and thus no pedal-drive possible) then you're not providing enough pedal force to prevent the chain slap.

 

[Zambam]

If you can live without the chain (and thus no pedal-drive possible) then you're not providing enough pedal force to prevent the chain slap.

How do I stop chain slap on bumpy roads when the traffic light is about to turn red and I need to come to a stop? Keep pedaling hard while squeezing the brakes?

 

[lnanek]

I use a cheap 3D printed hoop chain guide on bottom that works fine to prevent slap:

Amazon.com

There's way more advanced chain tensioners out there, though, like the gear on a spring derailleurs use.

Never had any issues top side, though. I use a really huge front cog and really small back cog, so my pedaling can keep up with the hub motor and keep the top of the chain tensioned.

 

[amberwolf]

How do I stop chain slap on bumpy roads when the traffic light is about to turn red and I need to come to a stop? Keep pedaling hard while squeezing the brakes?

No, but you would need something that keeps the chain tensioned sufficiently,(a clutched derailer might do this)

What Is A Bicycle Clutch Derailleur? - The Ultimate Guide

If we are used to talking about clutches for motorcycles and cars, they do exist for bicycles and are becoming more and more widespread. What are they?

backbiker.com

or otherwise prevents it from moving outside the straight line the top of the chainline should be in.

If tensioning doesn't fix it, you could add a chain-guide-tube such as those on various long-chain recumbents or other bikes; you'd need to make a standoff mount to the stays to keep the tube from being "sucked" on to the chainwheel(s) on the cranks. But they have disadvantages such as extra friction/drag on the chain, noise from chain rubbing on it if it's not aligned right, etc. They can also interfere with shifting gears depending on size, placement, length, etc.

chain-guide-tube such as those on various long-chain recumbents or other bikes - Google Search

Replacement Chain Guide Tube - Bike-On

Replace old and worn chain tube with new, sturdy chain protection. Choose from various lengths and flaring if needed for your trike.

bike-on.com

 

[richj8990]

Is it normal for the chain to make a loud slapping noise when going over bumps and the chain hits the chain stay? There are lot's of marks on the paint on the chain stay. Is there an adjustment to get rid of the noise? It's really loud and annoying. I thought the noise may be coming the the center stand so had it removed but the noise is still there.

If the noise is indeed coming from the chain, I am thinking of removing the chain and ride it throttle only. The ebike is nearly 70 lbs and a real dog to pedal. I get plenty of exercise on my 16 lb carbon fiber road bike which is fun to ride and go fast on. I see no point pedaling a heavy ebike if it has a big enough battery and range.

There are now clutch 'chain holders' on 9-speed rear derailleurs, at least some of them (I don't think they have them for 8-speed). 10-12 speed all should have them. It's about $200 to convert to a Microshift 9-speed with the clutch RD, and around $300 to convert to 10-12 speed. Unless of course you have a freewheel threaded hub and then you can't do it.

 

[E-HP]

There are wires zip tied to the underside of the chain stay. Wires are not chewed up so the slap is only on the topside. Maybe I wasn't pedaling hard enough? I will wrap some foam on the chain stay tomorrow, go for a test ride and see it the slap is quieter. If so that chain is coming off.

I like these. They are made to protect the chainstay, but I use them for cable routing along the chainstays too.

Amazon.com

 

[Zambam]

I wrapped the chain stay with a bicycle inner tube. It's less of a slap going over bumps but not totally gone. I ordered a chain breaker kit from Aliexpress. Should be here in less than 2 weeks. That should do the trick hopefully.

My ebike (the type with pedals) is the bike of choice for delivery workers here. I never see any of them use their legs. Throttle only!

 

[99t4]

My ebike (the type with pedals) is the bike of choice for delivery workers here. I never see any of them use their legs. Throttle only!

So look and see what they have wrapped around their chainstays and copy that to yours!

 

[nicobie]

I've been preaching about this stuff forever. Works great for wire/cable control, is kind of waterproof and easily removable, leaving no mess. I used to get the 4" rolls and cut them down but now I see that they make them in 2" size. Reusable if you are careful.

A Color for every bike.

Amazon link

 

[Zambam]

I've been preaching about this stuff forever. Works great for wire/cable control, is kind of waterproof and easily removable, leaving no mess. I used to get the 4" rolls and cut them down but now I see that they make them in 2" size. Reusable if you are careful.

A Color for every bike.

Amazon link

This stuff is made for hands and feet. How well does it hold up to weathering on an ebike? Looks like it can trap a lot of dirt. Can it be washed with cleaning agent without falling apart? Any pics on yours?

 

[Zambam]

So look and see what they have wrapped around their chainstays and copy that to yours!

I don't think they wrap their chain stays with anything. They are busy trying to earn a buck. I will take a closer look and see if their chain stays are chewed up like mine.

 

[Zambam]

I like these. They are made to protect the chainstay, but I use them for cable routing along the chainstays too.

Amazon.com

Looks like a nice product. I may buy one if I decide to keep the chain.

 

[nicobie]

This stuff is made for hands and feet. How well does it hold up to weathering on an ebike? Looks like it can trap a lot of dirt. Can it be washed with cleaning agent without falling apart? Any pics on yours?

I haven't had a problem with weather. Don't notice dirt either, but then again, I use the black stuff. It washes easy. Pics of my bike are in the link in my signature below.

 

[amberwolf]

I have something about like those from Grin ebikes.ca in their wiring tiedown/protection kits that someone gave me, used on the SB Cruiser's steering tiller to cover the wiring there starting a few years ago. The elastic in them is not UV resistant, so they lose their stretchiness / formfittingness, and now just kind of hang on the wiring. I used zipties to hold them after that. The velcro is still fine. They get dusty, but the infrequent rains we have wash them off. Not being down near the ground they don't have any chance to get dirty/muddy like they would on a stay, so I couldn't say how much of that they would trap.

I have considered using some of this instead:

https://www.amazon.com/dp/B07SW2W3N9

which I got to wrap parts of JellyBeanThePerfectlyNormalSchmoo who occasionally gets the notion of licking holes in herself. :/ It's not spectactular or anything, but it does what it is supposed to do, and would probably work for a while on the trike before having to be replaced, and it's cheap enough to not worry about.

There's other versions of it out there, possibly cheaper, or better.

 

[Zambam]

I don't think they wrap their chain stays with anything. They are busy trying to earn a buck. I will take a closer look and see if their chain stays are chewed up like mine.

I looked closely for nicks on the chain stays of a few well used Arrow 9 delivery ebikes (like mine) and surprisingly, none of them have nicks on their chain stay like on mine (their's was not wrapped).

I made this video picking up rear of my bike up a few inches and dropping it which simulates what I'd hear if I rode off the curb from the sidewalk. Chain is on the smallest cog in the rear. The chain stay is wrapped with an inner tube and it does not look like the chain is hitting it, yet you still hear a loud slap. Maybe the sound is coming from the heavy chain hitting other parts of the drive such as the front and rear cogs and derailleur?

Can't wait till the chain breaker arrives so I can remove the chain to find out.