spring loaded chain tensioner
- Thread starter Blazecc
- Start date
Well, Blazecc
I cant tell you right off hand where to get one, but I have seen them somewhere...cant remember where though.....
I know the spring loaded tensioner is like other bike kit mods in that you will get different opinions on them, all I can give you is what I have experienced myself so I will tell you to stay away from a spring loaded chain tensioner, I never had any luck with one, I'm not saying that it cant work and others dont use it.....but I had multiple chain issues, the main problem I had was when starting the engine, because all the force is on the bottom section of the chain when you release the clutch to start and this would overpower the spring on the tensioner and cause a lot of slack to be in the chain which caused it to come off the sprocket multiple times, also when you are going down a hill and let off the gas all the tension goes to the bottom of the chain which in my case also over powered the spring and caused the chain to come off.
I'm sure I could have used a much stronger spring and help that problem but I didn't want to put that much continuous pressure on my chain so I ditched the spring set up and just used a stationary Idler/Tensioner setup that has worked great on both my bikes for a combined 1400+ miles now.
If everything is adjusted correctly and in line a spring loaded tensioner is not an advantage at all in my opinion.
Hope this helps, best wishes
Peace
I cant tell you right off hand where to get one, but I have seen them somewhere...cant remember where though.....
I know the spring loaded tensioner is like other bike kit mods in that you will get different opinions on them, all I can give you is what I have experienced myself so I will tell you to stay away from a spring loaded chain tensioner, I never had any luck with one, I'm not saying that it cant work and others dont use it.....but I had multiple chain issues, the main problem I had was when starting the engine, because all the force is on the bottom section of the chain when you release the clutch to start and this would overpower the spring on the tensioner and cause a lot of slack to be in the chain which caused it to come off the sprocket multiple times, also when you are going down a hill and let off the gas all the tension goes to the bottom of the chain which in my case also over powered the spring and caused the chain to come off.
I'm sure I could have used a much stronger spring and help that problem but I didn't want to put that much continuous pressure on my chain so I ditched the spring set up and just used a stationary Idler/Tensioner setup that has worked great on both my bikes for a combined 1400+ miles now.
If everything is adjusted correctly and in line a spring loaded tensioner is not an advantage at all in my opinion.
Hope this helps, best wishes
Peace
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i found that if you can't take enough slack out of the chain to begin with you'll be asking for problems as well. i have one that mounts under the drive sprocket cover. the angle of the motor is all wrong. the tensioner pushes the bottom of the chain right into the top.Or it wanted to pull into the tire. mind you they are like 2.25'' wide. not to say others won't work but not for me.
I don't know of any commercially available spring loaded tensioners that have proven successful. There are a few members here who have designed and fabricated their own but the jury is still out on the success rate.
As Mapbike said, There really is no need for a spring loaded chain tensioner. The kit supplied items as well as those made by other bike builders all incorporate a slotted, or adjustable position bracket to allow compensation for chain/sprocket wear.
The real issue with the chain drive system is proper alignment and tension. You want a rear sprocket that spins true, no wobbling, and a chain that has 1/2 to 3/4" slack in the top run. The alignment is critical as well as the sprocket being installed with no wobbles.
Good luck.
Tom
As Mapbike said, There really is no need for a spring loaded chain tensioner. The kit supplied items as well as those made by other bike builders all incorporate a slotted, or adjustable position bracket to allow compensation for chain/sprocket wear.
The real issue with the chain drive system is proper alignment and tension. You want a rear sprocket that spins true, no wobbling, and a chain that has 1/2 to 3/4" slack in the top run. The alignment is critical as well as the sprocket being installed with no wobbles.
Good luck.
Tom
Good decision IMO, just get everything inline and adjusted properly and you will have a good set up that will give you many many miles of trouble free motorized bicycle riding, in many cases on these bikes I believe keeping things as simple as possible is the best route.
Good luck on the build, keep us posted with info. and pics if you can most of us here really enjoy being on the outside looking in at other peoples projects as they come together......
Peace
Good luck on the build, keep us posted with info. and pics if you can most of us here really enjoy being on the outside looking in at other peoples projects as they come together......
Peace
I bought the one from pirate , but with add on sprocket.
With the supplied spring , it was garbage , the spring is way too weak.
Found a different spring , much much stronger , and its working now , but it still jumps off the odd time. Kinda thinking to switch from the toothed idler , to the smooth might help , i think the teeth are to long and making it jump off.
Well we shall see if i can work the bugs out but for the cost , atm Im really not impressed.
<If I try to run without a tensioner >For whatever reason if i try to shorten the chain to the point that a tension er is not needed , the chain ends up too short (cant reconnect)or too long(jumps off).
With the supplied spring , it was garbage , the spring is way too weak.
Found a different spring , much much stronger , and its working now , but it still jumps off the odd time. Kinda thinking to switch from the toothed idler , to the smooth might help , i think the teeth are to long and making it jump off.
Well we shall see if i can work the bugs out but for the cost , atm Im really not impressed.
<If I try to run without a tensioner >For whatever reason if i try to shorten the chain to the point that a tension er is not needed , the chain ends up too short (cant reconnect)or too long(jumps off).
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All the reasons you just described are exactly why I stay away from the spring loaded tensioner set up, my chains never come off and the only time I have ever had a chain come off was when I was dabling with the spring loaded set up, a fixed, adjustable Idler/Tensioner set up works the best on these bikes IMHO, I have zero issues with mine.
If you want to make one heck of a good one use a skateboard wheel and groove out the center 5/16" deep for the chain to ride down in and with the good double bearings that are in the skateboard wheels you'll have an almost bullet proof Idler/Tensioner.
I included a pic of one that I made for one of my bikes, it works great, very simple to do, with very easy to find parts & pieces.
Peace
If you want to make one heck of a good one use a skateboard wheel and groove out the center 5/16" deep for the chain to ride down in and with the good double bearings that are in the skateboard wheels you'll have an almost bullet proof Idler/Tensioner.
I included a pic of one that I made for one of my bikes, it works great, very simple to do, with very easy to find parts & pieces.
Peace
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In my personal experience the durability of the spring loaded tensioner was not the trouble with them, I built one that was made from heavy steel that had zero flex in any area and also used a very strong spring with perfect chain alignment and it was still not reliable and would allow the chain to really dance around while coasting down a hill which would cause the chain to sometimes jump off the sprocket on a rough road or while leaning the bike into a turn, it would also jump off when I would pop the clutch to start the bike sometimes..... I actually broke one chain this way.
The conditions I just described here could be very dangerous if at any time the tensioner fails, allowing the chain to get hung up and lock up the rear wheel, could make for one heck of a wreck.
This is why I try to steer anyone clear of the spring tensioner, they are fine between an engine and a jackshaft where there isn't more than about 6-8 inches of space betwen the sprockets, but the longer the distance is between the sprockets the more side to side play you will have in a chain and this is where the problem is for using one on these bikes in my opinion, the distance between the sprockets is just to far and allows the chain to get too lose both up & down and side to side when the tensioner is overpowered by the amount of extra tension on it created by coasting the bike under no power or when popping the clutch to start the engine, under these two conditions all the pull is on the bottom portion of the chain which can potentially overpower even a strong spring.
Try one if you must, but It's not worth the possible risk in my personal opinion.
Peace
The conditions I just described here could be very dangerous if at any time the tensioner fails, allowing the chain to get hung up and lock up the rear wheel, could make for one heck of a wreck.
This is why I try to steer anyone clear of the spring tensioner, they are fine between an engine and a jackshaft where there isn't more than about 6-8 inches of space betwen the sprockets, but the longer the distance is between the sprockets the more side to side play you will have in a chain and this is where the problem is for using one on these bikes in my opinion, the distance between the sprockets is just to far and allows the chain to get too lose both up & down and side to side when the tensioner is overpowered by the amount of extra tension on it created by coasting the bike under no power or when popping the clutch to start the engine, under these two conditions all the pull is on the bottom portion of the chain which can potentially overpower even a strong spring.
Try one if you must, but It's not worth the possible risk in my personal opinion.
Peace
The stock kit idler works just fine if you bend it a lil bit to match chainstay angle and don't overtension the chain.
I can see how the swing arm being hung from the top like that would work if done right, because if the spring is over powered, the swing arm itself can be limited in how for it can travel downward so, if the travel is limited to a very short distance then there will never be enough slack in the chain to cause it to come off the sprockets, and under normal acceleration the chain will be kept in a constant tension, that design will work if set up so that the swing arm with the chain idler wheel has a very limited amout of travel in the negative.
I still don't believe a spring tensioner is needed on these bikes but if one was to be used for whatever reason, that design would be the way to go as long as the amount of downward travel was very limited.
Great post, this was a learning experience and just shows that a self adjusting spring tensioner can be designed to work on these bikes.....
Peace
Peace
I still don't believe a spring tensioner is needed on these bikes but if one was to be used for whatever reason, that design would be the way to go as long as the amount of downward travel was very limited.
Great post, this was a learning experience and just shows that a self adjusting spring tensioner can be designed to work on these bikes.....
Peace
Peace
That would take me a while to explain since it is a southern engineered proccess I used but I'll try to explain it best I can in the fewest amount of words possible.
The sketboard wheels that I have, have a recess on each side and the size of it across is the same size as a standard 3/8" ID hole size flat washer, I got a 3/8" bolt that is 2 1/2" long and put one flat washer on the bolt and then inserted the bolt through the bearing that are in the skateboard wheel and then put another of the flat washers on the bolt and then tighten a 3/8" nut all the way down so that the wheel is clamped tight and then the bolt becaomes a mandrel shaft that can be chucked up in a drill press.
(The cutter for making the groove).....I got a piece of 3/16" square keystock about 4" long and then I ground an opprox. 45+ or - degree angle, ( the angle isnt that important as long as it's a long enough angle so that it will work as a single knife edge and it needs to be fairly sharp so it will cut/groove the plastic material well, after sharpening the piece of key stock I tighten it up real good in my drill press vise that bolts to the bed/table of the drill press, the cutting edge of the keystock should be pointed at the wheel in a way so that when the drill press is on and spinning the wheel, the angled side of the keystock is facing the direction the wheel is spinning I then loosen the drill press table just enough that I can rotate it with a little pressure but not so lose that it will slide down when it's move slightly back and forth.
I then adjust the height of the cutter (keystock) so that when I rotate the press table it will line up where I want to start cutting the groove and then I turn the drill press on and very slowly move the cutter into the wheel and it starts removing material.....I cut the groove to roughly 1/2" and then I loosen the table and move it down about 1/8" of an inch and repeat this proccess until I get the groove cut to the 1/2" depth and the groove width wide enough for my chain to fit in with about 1/8" room to spare.
I hope this is understandable........it's kinda hard to explain some of this stuff when a few pics would sum it up real quick......which I dont have...!
At some point I may make a short video of the entire proccess and upload it on my youtube and then provide the link for anyone who is interested in doing this with the skateboard wheels and has these couple of tools, there are other ways to do this same thing if someone only has a 1/2" chucked hand drill and a bench vise, then all that would be needed to cut the groove would be the edge of a coarse wood rasp to cut the groove while the hand drill was secured in the vise and the wheel with the bolt/mandrel was being spun in it, this might take a little bit longer to do but would not be that hard at all.
Hope something I said here helps you out, sorry it's so dang long, just didn't know how to make it any shorter and still make the needed points.
Peace
The sketboard wheels that I have, have a recess on each side and the size of it across is the same size as a standard 3/8" ID hole size flat washer, I got a 3/8" bolt that is 2 1/2" long and put one flat washer on the bolt and then inserted the bolt through the bearing that are in the skateboard wheel and then put another of the flat washers on the bolt and then tighten a 3/8" nut all the way down so that the wheel is clamped tight and then the bolt becaomes a mandrel shaft that can be chucked up in a drill press.
(The cutter for making the groove).....I got a piece of 3/16" square keystock about 4" long and then I ground an opprox. 45+ or - degree angle, ( the angle isnt that important as long as it's a long enough angle so that it will work as a single knife edge and it needs to be fairly sharp so it will cut/groove the plastic material well, after sharpening the piece of key stock I tighten it up real good in my drill press vise that bolts to the bed/table of the drill press, the cutting edge of the keystock should be pointed at the wheel in a way so that when the drill press is on and spinning the wheel, the angled side of the keystock is facing the direction the wheel is spinning I then loosen the drill press table just enough that I can rotate it with a little pressure but not so lose that it will slide down when it's move slightly back and forth.
I then adjust the height of the cutter (keystock) so that when I rotate the press table it will line up where I want to start cutting the groove and then I turn the drill press on and very slowly move the cutter into the wheel and it starts removing material.....I cut the groove to roughly 1/2" and then I loosen the table and move it down about 1/8" of an inch and repeat this proccess until I get the groove cut to the 1/2" depth and the groove width wide enough for my chain to fit in with about 1/8" room to spare.
I hope this is understandable........it's kinda hard to explain some of this stuff when a few pics would sum it up real quick......which I dont have...!
At some point I may make a short video of the entire proccess and upload it on my youtube and then provide the link for anyone who is interested in doing this with the skateboard wheels and has these couple of tools, there are other ways to do this same thing if someone only has a 1/2" chucked hand drill and a bench vise, then all that would be needed to cut the groove would be the edge of a coarse wood rasp to cut the groove while the hand drill was secured in the vise and the wheel with the bolt/mandrel was being spun in it, this might take a little bit longer to do but would not be that hard at all.
Hope something I said here helps you out, sorry it's so dang long, just didn't know how to make it any shorter and still make the needed points.
Peace
The Beauty of a spring loaded Idler wheel is that it takes up chain lash. For those motors with Auto clutch, this is a critical function. Also.. IT allows for quick gear box sprocket swaps.
If you have access to a lathe................
One thing I didn't see mentioned, or I missed it, is that you need to check the construction of the skate board wheel you plan to use. Some of the cheaper ones are a plastic wheel coated with a rubber layer; sort of like a re-tread tire. If you try to use those the rubber will fly off, just like a re-tread and you'll be left with a plastic wheel, or back to square one.
The pricier wheels are solid, one piece and preferably made of polyurathane.
Ask Bike Guy Joe about cutting into a two layered wheel
If you happen to know anyone in the elevator repair business you might be able to scrounge an elevator guide wheel. I scored a couple of these from a mechanic who serviced elevators in the building where I used to work. These were originally three inches in diameter, I cut them down to two inches and grooved them on a lathe. They have 5/16" bearings, both sides and never show any signs of wear after several hundred miles.
Tom
One thing I didn't see mentioned, or I missed it, is that you need to check the construction of the skate board wheel you plan to use. Some of the cheaper ones are a plastic wheel coated with a rubber layer; sort of like a re-tread tire. If you try to use those the rubber will fly off, just like a re-tread and you'll be left with a plastic wheel, or back to square one.
The pricier wheels are solid, one piece and preferably made of polyurathane.
Ask Bike Guy Joe about cutting into a two layered wheel
If you happen to know anyone in the elevator repair business you might be able to scrounge an elevator guide wheel. I scored a couple of these from a mechanic who serviced elevators in the building where I used to work. These were originally three inches in diameter, I cut them down to two inches and grooved them on a lathe. They have 5/16" bearings, both sides and never show any signs of wear after several hundred miles.
Tom
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Yep........right on brother Tom
Shan
Shan
If you have access to a lathe................
One thing I didn't see mentioned, or I missed it, is that you need to check the construction of the skate board wheel you plan to use. Some of the cheaper ones are a plastic wheel coated with a rubber layer; sort of like a re-tread tire. If you try to use those the rubber will fly off, just like a re-tread and you'll be left with a plastic wheel, or back to square one.
The pricier wheels are solid, one piece and preferably made of polyurathane.
Ask Bike Guy Joe about cutting into a two layered wheel
If you happen to know anyone in the elevator repair business you might be able to scrounge an elevator guide wheel. I scored a couple of these from a mechanic who serviced elevators in the building where I used to work. These were originally three inches in diameter, I cut them down to two inches and grooved them on a lathe. They have 5/16" bearings, both sides and never show any signs of wear after several hundred miles.
Tom
i been using the one from live fast and it works great using one on two bikes been on now for two years and no problems
