#40 Chain Stretching, chain only 2 months old.

[ZnsaneRyder]

My New Bicycle Trailer has a #40 chain from clutch to wheel. Last week, I broke my Master-Link when I was riding, and had a LONG pedal back home over 10 miles until I replaced the Link, then all was good and I've been riding fine since.

Today, I was doing a check-over of my ride, for the usual maintenance, and I noticed the chain is stretched. What I mean is that on the top of the sprocket, the rollers touch the front of the sprocket teeth, but on the bottom of the sprocket, they touch the back of the teeth. I've had to re-tension the chain a few times before, and now I see why.

It's a bit of a surprise how it lines with the teeth, because I only have a 32T sprocket, so it's not a very big sprocket. The chain still sits deep enough in the teeth fine, but I'm wondering for how much longer.

They make both #35 and #40/41 chain clutches for your typical small 3/4 shaft engine, (196cc Honda Clone) so I can't go any bigger on chain size. My 10T clutch and 32T sprocket both fit a #41, but I'm using a #40, which works great, is slightly wider, and was slightly less $$$ than a #41.

What causes chain stretch like that on a new chain? It is from going 50Mph, or having the trailer bounce on bumps, or dirt and sand on the chain, or is it that these go-kart chains are meant to wear out and not meant for transportation use? I like having a chain compared to a V-Belt for sure, but it would be a bummer if I still have to get a new chain every few months.

 

[ZnsaneRyder]

BTW, these pics are older, it has a cargo rack on it now. I used these pics to show the drivetrain setup.

 

[ZnsaneRyder]

For the life of the chain, would a #41 chain on #41 sprockets be any different than a wider #40 chain on the #41 sprockets?

 

[BradenM]

Znsane, how tight are you setting it up?
To me, a new chain stretching means it's excessive load and little flex.

 

[Kaptain Krunch]

All chains have a break in time where they "strench more" rider for another few weeks, then if it got bigger, you probably need a stronger chain.

 

[ZnsaneRyder]

Znsane, how tight are you setting it up?
To me, a new chain stretching means it's excessive load and little flex.

Only as tight as I should. I don't overtighten it to extend the life of my clutch bushing, but I make the chain firmly tight, then it gets just a little loose the first ride, but stays right, but over time, I have to re-tension it.

I need to do it again, that would make it 4 times.

It rides good, and I've been going easier on the throttle today, by allowing it to slip the clutch up to speed, instead of just jamming on it and making it lock up.

I'm having a feeling it's the really tall gear ratio of 10T-32T that's stressing the chain.

 

[ZnsaneRyder]

All chains have a break in time where they "strench more" rider for another few weeks, then if it got bigger, you probably need a stronger chain.

Ok, I'll keep that in mind. I tensioned my chain again. It was getting a bit loose. I rode for 16 miles tonight and it's still tight. That's a good sign. I'll see if it stays tight tomorrow.

 

[doesgo]

ZnsaneRyder, do you have a thread for this build-up or an explanation of your ride? I'm extremely curious about it but don't want to hijack this thread.

 

[ZnsaneRyder]

ZnsaneRyder, do you have a thread for this build-up or an explanation of your ride? I'm extremely curious about it but don't want to hijack this thread.

I need to make a thread for my new trailer. I am just short on pictures, but maybe I'll do it anyway. I have a rack with a small cooler, gasoline can, and backpack to carry stuff on it now.

 

[ZnsaneRyder]

New Thread in the Project Forum:
http://www.diygokarts.com/vb/showthread.php?p=44660

 

[newrider3]

Stretching is fairly normal with any roller chain, as long as it isn't really excessive. Also, if a 10 mile ride unpowered is long for you, you need to get out without the engine more often.

 

[doesgo]

Towing a 100lb trailer adds a bit to the strenuousness of it, though.

 

[zero1dhd]

first off, isn't #40, 41, and 42 just bicycle chain?? Definitely not meant for a 200cc motor. You need a heavier chain for sure. I think #42 is heavier than 41 too. (it might be #420) And I'm not 100% sure, but I think #35 is stronger than #40 even though the links are smaller, they are built heavier. Motorcycle/dirtbike chain would be much more appropriate, I don't remember the # offhand, but it's like some odd # like 2a or something.
Also/Or devise a chain tensioner with a heavy spring. Having the chain tight with that much torque will stretch chain no matter what. Even though it's a roller chain, when you lay on the gas, the chain wants to wrap around the motor sprocket, so if it's tight it'll just stretch it, think about the torque of the motor, a motor like that is probably putting out something around 10ft/lbs of torque (just guessing) wrapping around a sprocket that's what like two inches in diameter.
Understanding the clutch issue, devise a chain tensioner with a nice heavy spring, push or pull, depending on what makes most sense for the positioning, and put some slack in the chain.

 

[jr dragster T]

Dirtbikes and motor cycles commonly use #520 chain zero1dhd. 41 chain is NOT bicycle chain and is pretty heavy duty. Look at its static load. Its more then plenty for this pusher trailer. A good #35 pitch chain will hold up to 50+ HP.

 

[ZnsaneRyder]

Well, the chain so far appears to have stopped stretching, and I've had it really tight since the last time I mentioned it. It has more drag, when pedaling it, but takeoff with engine is much tighter, and shakes less at high speed with a tight chain. I had to lubricate the teeth on the clutch though, because it was wearing the teeth some on my clutch, but adding the lubricant helped a lot with that, and the drag.

The chain still is very tight. I don't want to eat the teeth off my clutch. Should I just keep it lubed, or should I loosen it a little bit?

Or should I just get a new chain??? I'm really thinking about it.

 

[ZnsaneRyder]

Update, I checked on it today, and realized the chain is not overtight, and has over 1/4 of wobble if I wiggle the chain. I guess it still stretched a tiny bit. I'm leaving it alone. I sprayed the sprocket and whole chain again with white lithium lubricant. It's riding really nice, and smooth now that it's lubricated. I'm wondering if a stretched chain puts wear on the clutch sprocket.

I have an extra clutch, but I'm trying to make this one last. I'm going to keep after it with heavy lubrication. I'm still going to get a new chain to have when I go to use my new clutch.

 

[ZnsaneRyder]

Update, I'm replacing the chain. I just got 10FT of new #40 chain, so I'll be fitting the replacement. The stretched old chain is not good for my sprockets. Also the old chain is loose AGAIN. Also the links and rollers now have spaces in them. This chain is toast!

To prevent future wear of the chain, I'm going to accelerate slower, pedal more, lube the clutch more often, ride slower than usual by keeping it under 40 most of the time, and not let anymore 15 year old neighborhood kids ride it. (I tell him to throttle easy on takeoff, he rolls about 20 feet easy, then floors it to max, I was pissed, even I don't ride it like that, lol)

My old clutch is still good, despite the worn teeth. I'm going to keep this clutch for around town, and use my extra clutch for long trips. I also find you can buy replacement clutch sprockets.

 

[EagleTalons]

Did you buy the economy chain or performance chain?

 

[ZnsaneRyder]

The chain I used is whatever #40 chain that Tractor Supply sells.

I am wondering if other places have a #40 with a higher grade steel. I did look up stainless steel chains, but they are super expensive, nearly $80 for a chain!

My 10T clutch sprocket, has a funny wear pattern. Every other tooth is broken in half. 5 short teeth, 5 long teeth, but spaced evenly.

I put the new chain on tonight, and it seems to roll fine on the clutch, much smoother than the old chain.

I'm worried about the sprocket wear on my clutch. I'm going to take it for a ride tomorrow and see how it rides. If it rides ok, then fine, but if it's noisy or shows wear, I'll change to my other clutch.