420 chains and sprockets

[chunky0071]

Ok here is a can of worms has any one tryed running a 420 chain and sprocket combo why you ask by going to a 420 set up you could drop almost 2lbs in rolling weight or mass increasing hp torque and speed. I know 420 chain is smaller than 428 but in HD chains strength diiference is only by a few hundred pounds. EX. a EK 420 Mx chain has a tensile strength of 5200 lbs most 428 hd chains are around 4900 to 5400 so the only thing to find is the sprockets since strength is not a problem! Now that your gears are turning does any one know of some where to get the front sprockets cut for the slipper sprockets?

[Logan #34's Dad]

Great idea! As long as we can find a strong enough chain, It makes sense. Is there a stronger chain out there than the one you mention?
I'm sure Rebel Gears will make what you want and they have all the right measurments already.

[chunky0071]

Thats the best I have found so far but I would be willing to bet that there are better ones out there but even so the standard 428 is between 4200 and 4800 which is what most run. You only get into the 5000 plus range when you get into the gold and mx series chains. The DID 428 HD chain is only 5500 so you are not loosing much to strength specially if you figure in the loss in weight.

[Coley'sdad#8]

with all the twisting, bending and flexing of this high quality steel the sprocket alignment is really crappy on these machines anyway and even on a really nice built quad there is still more flex than on a motorcycle that has several guides. Being said the 420 chain has an inside width of 6.35mm and the 428 has a inside width of 7.95, i would personally take the extra width which will aid in axial strength (side flex) to keep from pitching a chain.
2# is not alot of weight and the fact is that all of the weight is not "sprung" or "unsprung" weight since 1/3 of the combo is on your fixed in place motor and ft sprocket and the other 2/3 is on your swingarm.
Here's the food for thought aspect, when that chain / sprocket combo is spinning it has centrifugal force slinging outward , it is acting like a gyroscope so is it actually "sprung" at all.:confused:

[chunky0071]

Sprung and unsprung weight is not my piont to going to a 420 chain but that is a good point. It's the reduction in rolling mass that increases HP. If you have a sport bike and you are building it to get more power to the ground one thing you need to do is put a 530 chain in place of the 630 in some cases you would even use a 520 . The reason for this is to reduce the rotating mass. Just like a lighter fly wheel or lighter rear clutch. The less weight you are having to turn over through out the drive train the more power that can reach the ground.

[chunky0071]

[QUOTE]Originally posted by Logan #34's Dad
Is there a stronger chain out there than the one you mention?



To answer this ? yes http://sidewindersprockets.com/titanium_chain.html
4000 to 10000LBS

[LT80]

I run 428 sprockets with #40 chain and can push a machine with one finger.
I've never had a chain break.

[jweidner]

Hey Guys,

I would agree that Side Winder will have everything you need. I ran TRX 90 last year and Raptor 125 this year and have changed the chain and sprockets both years. Have run half season so far and there isn't any signs of wear.

Thanks,
Precision Motor Worx
Tuski #99 Youth ATV PA STATE Champ series Hare Scramble

[Logan #34's Dad]

Originally posted by LT80
I run 428 sprockets with #40 chain and can push a machine with one finger.
I've never had a chain break.

You ain't had that #40 chain break cause them LT80's don't put out any power.....:devil:

[jweidner]

I think you get what you pay for when it comes to all ATV equipment. I've had the $25 chains that stretch one inch in an hour of riding. Will not buy another one.

[LT80]

Originally posted by Logan #34's Dad
You ain't had that #40 chain break cause them LT80's don't put out any power.....:devil:


Ok,OK..I get it...no more doughnut jokes....:D :D