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One tooth larger on the front sprocket


RodeRash

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I'm gonna take a shot at this...

Assuming you're running the stock 530 chain, the correct diameter of the stock 17 tooth sprocket is around 3.4". An 18 tooth sprocket would be around 3.6", a difference of .200".

However you would have to halve that because the chain is working on the radius of the sprocket. So were down to .100".

However, the chain operates on the root radius of the sprocket, so that number may be off a little.

However .100" assumes you have the chain adjusted exactly the same for both applications. A loose chain with the stock sprocket may have the same wheelbase as a tight chain with the bigger sprocket.

I wouldn't worry too much about it

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Mike, RoadRash you are going the wrong direction, 16 man 16, drives out of corners like a mofo

I already have enough power. (It's a BUSA). :)

What I'm really looking at is up one in the front and up 3 in the rear. (So, almost no effective change in overall gear ratio)

It's something Suzuki did with the Gen II and I'm trying to decide if I have enough swingarm adjustment.

I'm looking for a few improvements from this setup.

A little more clearance between chain and swingarm at either end of suspension travel, which is worth looking at since I raised the ride height.

A little less wheelbase for improved handling.

Less stress on the chain going around larger sprockets.

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Personally the wheelbase length changr will be do minimal that you wouldnt notice.

Go with a more triangle shaped tire if you want turn in.

I know of one person who did a gen 1 wheelbase shortning by cutting the swingarm down 2 inches.

Granted he probably had 30k tied up in his busa. She was awesome, and just nasty. This was probably 15 yrs ago.

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D.I.D x... Chain, 18 tooth sprocket. Was in the green when I installed it.

The only problem is that I have to adjust my speed reference.

60 in a 55 was good for the first 14 years that I owned her.

Now 60 indicated in a speed trap IS 60.

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The 3 up in the rear will do a lot more for changing length than the 1 up front will. I've never geared a busa, or played with one at all; maybe you can grind the adjustment slots longer if needed.

Edit-there are certain combinations to avoid based on the number of teeth interacting negatively, but if Suzuki used what you're after then I assume they did the math and it should be fine.

Edited by superhawk996
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Just thought, since you're only trying to shorten up; how bout just removing a link or two from the chain?

Edited by superhawk996
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Mike, I didn't notice any differance in wheelbase length. The speedo is accurate according to my GPS.

Lost a little acceleration. I like how it loafs at near triple digit. The 18T has been on there for about ten years.

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On my bike, changing from 17-40 to 18-43 will shorten the distance from sprocket to sprocket by a little under .65 inch.

I have enough adjustment for that. I will probably make this change next time I need a new chain.

Posted Yesterday, 03:51 PM

Edit-there are certain combinations to avoid based on the number of teeth interacting negatively

Please explain, if not here, start another thread.

Here is a link that will let you calculate most everything related to chain and sprocket changes.

It has a section where they look at possible chain wear.

The same tooth same link section can show you combinations to avoid.

Gearing Commander

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Mike, RoadRash you are going the wrong direction, 16 man 16, drives out of corners like a mofo

Isn't this opposite? Larger front on a road bicycle means harder to push since more drag due to more wheel friction. You go a greater distance per revolution. So would that not equate to greater torque with same rpm?

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Mike, RoadRash you are going the wrong direction, 16 man 16, drives out of corners like a mofo

Isn't this opposite? Larger front on a road bicycle means harder to push since more drag due to more wheel friction. You go a greater distance per revolution. So would that not equate to greater torque with same rpm?

Wheel friction has nothing to do with sprockets. Larger front will have the same effect whether bicycle or motorcycle; it's harder to get going but you'll get more speed for a given input RPM, whether that RPM is legs or pistons.

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I wouldn't worry about the wheelbase. But it will look pretty awkward.

attachicon.gifmacrodontia.jpg

I was gonna stay outta this thread due to my ignorance on the subject.

But damn, Joe. What was THAT all about?

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Mike, RoadRash you are going the wrong direction, 16 man 16, drives out of corners like a mofo

Isn't this opposite? Larger front on a road bicycle means harder to push since more drag due to more wheel friction. You go a greater distance per revolution. So would that not equate to greater torque with same rpm?

Wheel friction has nothing to do with sprockets. Larger front will have the same effect whether bicycle or motorcycle; it's harder to get going but you'll get more speed for a given input RPM, whether that RPM is legs or pistons.

I think we are on the same page, but just looking at it differently. We agree that you go farther with each revolution of the larger front spoke. We agree that it takes more effort for turning that larger spoke one revolution (legs or pistons, as you say). I described it as more friction since tires will be in contact with road for a longer distance with the same mass per revolution. Perhaps friction is not technically the correct term, but maybe it is. I dunno. You opined that the larger front spoke equates to faster speed. I would agree if the power turning the spoke at the same rpm as the smaller OEM spoke is present. The question I was raising is why does Roadrash indicate you get out of corners "like a mofo" I.e faster with the smaller front spoke?

I often get confused with these descriptions since it does not make sense to me given the discussions above. I do realize that smaller front spoke is easier to turn so therefore with constant force, getting to higher rev ranges is faster and thus peak torque can be achieved sooner. Is this why smaller front spoke = faster speed?

Next confusing topic: why over square engine (i.e. bigger bore than stroke) works for sport bikes (eg get to higher revs faster) and longer stroke bikes (eg twins) work for low end torque for cruisers? Engineers, feel free to chime in.

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How about this for simple, a 16 tooth front sprocket is like going through the turn in 3rd gear and a 18 tooth like going through in 4th gear. It is the same as a car rear end gearing if you are familiar with that. You can get a Mustang with 3:55 or 4:10 gearing. The 16 tooth would be the 4:10 in my example.

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Mike, RoadRash you are going the wrong direction, 16 man 16, drives out of corners like a mofo

Isn't this opposite? Larger front on a road bicycle means harder to push since more drag due to more wheel friction. You go a greater distance per revolution. So would that not equate to greater torque with same rpm?

Wheel friction has nothing to do with sprockets. Larger front will have the same effect whether bicycle or motorcycle; it's harder to get going but you'll get more speed for a given input RPM, whether that RPM is legs or pistons.

I think we are on the same page, but just looking at it differently. We agree that you go farther with each revolution of the larger front spoke. We agree that it takes more effort for turning that larger spoke one revolution (legs or pistons, as you say). I described it as more friction since tires will be in contact with road for a longer distance with the same mass per revolution. Perhaps friction is not technically the correct term, but maybe it is. I dunno. You opined that the larger front spoke equates to faster speed. I would agree if the power turning the spoke at the same rpm as the smaller OEM spoke is present. The question I was raising is why does Roadrash indicate you get out of corners "like a mofo" I.e faster with the smaller front spoke?

I often get confused with these descriptions since it does not make sense to me given the discussions above. I do realize that smaller front spoke is easier to turn so therefore with constant force, getting to higher rev ranges is faster and thus peak torque can be achieved sooner. Is this why smaller front spoke = faster speed?

Next confusing topic: why over square engine (i.e. bigger bore than stroke) works for sport bikes (eg get to higher revs faster) and longer stroke bikes (eg twins) work for low end torque for cruisers? Engineers, feel free to chime in.

A smaller front sprocket will allow for quicker acceleration since it gives the engine more leverage to rotate the tire and make you go. As for pulling out of a corner, that will depend on what gear you're in. A smaller sprocket may be an advantage or disadvantage as it'll somewhat dictate which gear you can run in the turn. A smaller sprocket will only give you higher speed if you don't have enough power to turn a larger sprocket. Generally speaking, a smaller one will give quicker take off acceleration while limiting the top speed.

As for bore/stroke ratios, it would take hours to type out all the details, but basically the longer stroke gives more leverage to rotate the crankshaft but has a lower RPM limit. With a long stroke the piston speed is higher for a given RPM and is one of the limitations to spinning a long stroke motor at high RPM. A larger piston allows for bigger valves and higher flow rates good for high RPM horsepower. That larger piston is pushing on a shorter lever which limits the torque but it can spin much faster making more horsepower. The long stroker is like a bulked up weightlifter (torque) where the short stroker is like a skinny sprinter (horsepower).

Edited by superhawk996
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I often get confused with these descriptions since it does not make sense to me given the discussions above. I do realize that smaller front spoke is easier to turn so therefore with constant force, getting to higher rev ranges is faster and thus peak torque can be achieved sooner. Is this why smaller front spoke = faster speed?

no it does not equal faster speed. Yes, it will provide faster accelration out of corners.

Jeff, CBR-RR-XX-CESS and I argue about this topic all the time. Jeff rode his 954 at redline all the time and he rides his XX in the same manner. I ride my XX at redline also. I just don't like to shift as much. With an 18 tooth sprocket I can go an honest 105mph in seond gear gps approved. Sure it will not accellerate out of corners as hard as as 16tooth but when Im in high gear it is smooth with the rpms low and the speedo is accurate and the mpg is better, the chain life is great. Too each thier own. I have had the 18 tooth on the XX for well over a decade. Won't go back.

What do you value most?

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"What do you value most?"

Beating you out of the corners

Agree! Grunt out of the corners, I feel pretty good with the grunt I get with an 18. Edited by SLyFoXX
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