chain and sprocket size 41, 40, 420, 428

#1
I bet this has been beat to death on here, but I did a search and didn't find what I was looking for.
From what I can tell all sprockets marked #40 are not the same. 40 and 41 are the same pitch but different width. 2 sprockets I have are marked "40" but are thinner, I think to fit 41 chain. 2 of my sprockets are marked "40" and are thicker and do not fit the chain I have. I thought I had both 40 and 41 chain, but neither fit, too narrow. I will take a sprocket to Tractor Supply and match it up to chain to see what fits. My question is if the only difference is width, then the wider chain will fit on the narrower sprocket, but is this a good idea? Will the extra slop cause wear issues or make it more prone to jumping off the sprocket? And how the hell do I tell what I am buying when they all say "40" but some are a 1/16th of an inch narrower? Or am I picking the fly poop out of the pepper here? (meaning it aint an issue?)
 
#2
Maybe this will help a little.

ChainGuide.jpg

Note the in between plates size/gap, this is where the sprocket thickness has to match the chain.
 
#3
View attachment 98538

Note the in between plates size/gap, this is where the sprocket thickness has to match the chain.
This was info I had found and that using a wider chain on a narrower sprocket could be done. One of my sprockets is sold as a 40, but is narrow enough for a 41. So I assume, that putting a 40 chain on a 41 sprocket is done a lot. But with that much slop will the chain stay on or wear like it should? In my old age I have learned just because you can do something doesn't mean you should do it. Looking for real life experience advice here. Running a 389/13hp motor with loads over 500lbs, so I think the chains will earn their keep.
 
#4
I bet this has been beat to death on here, but I did a search and didn't find what I was looking for.
From what I can tell all sprockets marked #40 are not the same. 40 and 41 are the same pitch but different width. 2 sprockets I have are marked "40" but are thinner, I think to fit 41 chain. 2 of my sprockets are marked "40" and are thicker and do not fit the chain I have. I thought I had both 40 and 41 chain, but neither fit, too narrow. I will take a sprocket to Tractor Supply and match it up to chain to see what fits. My question is if the only difference is width, then the wider chain will fit on the narrower sprocket, but is this a good idea? Will the extra slop cause wear issues or make it more prone to jumping off the sprocket? And how the hell do I tell what I am buying when they all say "40" but some are a 1/16th of an inch narrower? Or am I picking the fly poop out of the pepper here? (meaning it aint an issue?)
Goggle and chain suppliers
 

chrisr

Active Member
#5
The wider 40 sprockets with a 40 chain will be stronger than the skinnier 41 sprocket and chain. The wider the sprocket the better to help distribute the load across the teeth.
 
#6
Then again you may have a mix

of standard us made chain or sprockets, even when they have the same spec numbers they will not match/fit like they should.

The chart below is a Chinese spec chart that I will figure will only fit correctly on a Chinese manufacture sprocket hint hint ;).


926574917_770.jpg

PS the load is more of a concern depending on how harsh is the stop and start, this will really increase tear and wear on your chain and sprockets provided lubrication is taken care off.
 
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