What size chain do i use for a lifan mso 140cc
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Cactus Jack
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You need a 102 link chain ...
Cactus Jack
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A #428 will be stronger and last longer but they cost more plus you'd need to buy #428 pitch sprockets to suit ... A high quality #420 like a DID or RK will be OK ... I got the 102 link chain length by counting the links of a new chain taken off a new DHZ twin pipe framed bike with a 138 lifan in it and a 435 mm swingarm ... I don't use the stock chains and replace them straight away ...
The 102 links is a basic size ... when you buy a new chain it will most likely be longer ie 110 or 120 link and need to have links removed to fit your bike ...
To be safe you should do what the guys told you to do on your other thread ... BUT don't do it with the chain tight while the wheel is as far forward as it can go UNLESS you check it with the rear shock off and the axle , swingarm pivot , and engine sprocket shaft centre lines all aligned in a dead straight line ...
The reason why is that the chain pulls tightest when the swingarm passes that parallel alignment point ... so if you do it tight with the swingarm angled down while the shock is on ... when you sit on the bike or go for a ride , the chain will pull hard on the engine shaft and axle bearings and that can stretch the chain unnaturally ... or could possibly damage the wheel bearings , sprocket shaft bearings , or even snap the sprocket shaft ...
Countless people probably haven't got a clue of how basic geometry works and complain that their chain keeps stretching ...
... If the swingarm pivot axis was on the same axis as the sprocket shaft ... the chain would stay the exact same tension everywhere throughout the full range of movement because it's moving thru a constant fixed radius ... but since the swingarms axis point is 85 mm shorter than the countershaft , the chain swings thru a smaller arc meaning it'll get looser when the swingarm is above or below parallel alignment of all 3 axis points ... Anyone can check for themselves in practical or on paper to verify that what I'm saying is correct ... People who sell these bikes should supply chain tensioning info to teach people about all this stuff ... If it's done wrong it can be very damaging to a bike ... I've heard knuckle heads say in threads that they snapped the sprocket shaft off Lifan 140's ... In their heads they'd THINK it happened because the metal was weak or something but what they DON'T understand is that the mechanical leverage via the cam-like action produced by the varying geometry can exert TONS of force on all of the parts ...
The 102 links is a basic size ... when you buy a new chain it will most likely be longer ie 110 or 120 link and need to have links removed to fit your bike ...
To be safe you should do what the guys told you to do on your other thread ... BUT don't do it with the chain tight while the wheel is as far forward as it can go UNLESS you check it with the rear shock off and the axle , swingarm pivot , and engine sprocket shaft centre lines all aligned in a dead straight line ...
The reason why is that the chain pulls tightest when the swingarm passes that parallel alignment point ... so if you do it tight with the swingarm angled down while the shock is on ... when you sit on the bike or go for a ride , the chain will pull hard on the engine shaft and axle bearings and that can stretch the chain unnaturally ... or could possibly damage the wheel bearings , sprocket shaft bearings , or even snap the sprocket shaft ...
Countless people probably haven't got a clue of how basic geometry works and complain that their chain keeps stretching ...
... If the swingarm pivot axis was on the same axis as the sprocket shaft ... the chain would stay the exact same tension everywhere throughout the full range of movement because it's moving thru a constant fixed radius ... but since the swingarms axis point is 85 mm shorter than the countershaft , the chain swings thru a smaller arc meaning it'll get looser when the swingarm is above or below parallel alignment of all 3 axis points ... Anyone can check for themselves in practical or on paper to verify that what I'm saying is correct ... People who sell these bikes should supply chain tensioning info to teach people about all this stuff ... If it's done wrong it can be very damaging to a bike ... I've heard knuckle heads say in threads that they snapped the sprocket shaft off Lifan 140's ... In their heads they'd THINK it happened because the metal was weak or something but what they DON'T understand is that the mechanical leverage via the cam-like action produced by the varying geometry can exert TONS of force on all of the parts ...
Sabertooth_buterfly
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well said cactus
I prefer 428 for the extra strength and life span so when I replace a chain on any bike that has a 420 I always get sprockets to change over to 428 at the same time. This is also good practice because runing a new chain on old sprockets can excelerate chain wear as well.
Saber
I prefer 428 for the extra strength and life span so when I replace a chain on any bike that has a 420 I always get sprockets to change over to 428 at the same time. This is also good practice because runing a new chain on old sprockets can excelerate chain wear as well.
Saber
Sabertooth_buterfly
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I dont buy chain from ebay because it is hard to tell what quality you will actualy get. chains can be best got from a shop. good brands are good insurance against chain snaps and resulting damage, I like DID and RK brands but there other good brands. The main difference between 420 and 428 is that 428 has wider links so there is more contact area between the chain and the sprockets this helps the chain to take the load better
Saber
Saber
I_THUMP
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A good quality chain is a must and I like DID and have never snapped a DID 420 chain. They are available on the net for a good price but you will need to cut it to size which is not that hard to do.
This is a good price 428 DID chain
Dirt Bike Racing Chain D.I.D. #428 140cc 125cc - eBay Other Makes, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 13-Jan-09 22:27:40 AEDST)
You can also buy a chain breaker if you think it will be easier for you to cut the chain.
CHAIN BREAKER - eBay Other Makes, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 04-Dec-08 07:51:46 AEDST)
This is a good price 428 DID chain
Dirt Bike Racing Chain D.I.D. #428 140cc 125cc - eBay Other Makes, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 13-Jan-09 22:27:40 AEDST)
You can also buy a chain breaker if you think it will be easier for you to cut the chain.
CHAIN BREAKER - eBay Other Makes, Bike Parts, Motorcycle Parts, Accessories, Cars, Bikes, Boats. (end time 04-Dec-08 07:51:46 AEDST)
Sabertooth_buterfly
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that looks the goods I THUMP and at a good price
Saber
Saber
