1 down = ?
11-23-2004, 11:26 AM
#22
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Join Date: Mar 2003
Location: San Diego, CA
Posts: 784
Re: 1 down = ?
Originally Posted by iceberg
see what i am talking about , everyone has diff views on this but thats cool and your point is well taking .
heres my
for some reason 1 down on 900 RR dident do much for me ,but when i went up 3 on my gsxr it made the world of diff . i know there 2 diff bikes but why did it seem like that for me with 3 up on gsxr i could gas it up in 3rd , on my 900 i have a hard time geting it up in 2nd with the one down .
heres my
for some reason 1 down on 900 RR dident do much for me ,but when i went up 3 on my gsxr it made the world of diff . i know there 2 diff bikes but why did it seem like that for me with 3 up on gsxr i could gas it up in 3rd , on my 900 i have a hard time geting it up in 2nd with the one down .I know others may disagree with me, but I am just sharing my opinion and personal experience with many sprocket set-ups.
I maintain that while making changes that have an equal ratio at the end still have a different effect based on where you add or subtract teeth.
11-23-2004, 11:35 AM
#23
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Re: 1 down = ?
example 1: if you were to leave stock rear sprocket and only go down 2 in the front, it would not be equal to going up 6 in the rear.- your top speed would stay very high, but there would be alot more torque from the engine making wheelies easier and making the bike much faster off the line.
example 2: if you were to leave the front stock and go up 6 in the rear, again it would not give you equal results to 2 down in front.- your top speed will reduce because the wheel cannot rotate as fast anymore and the rpm at which your powerband kicks in will be reached at a slower travel speed.
either way or a combination of the two ways will make wheelies easier, but i belive that they yeild different effects/results.[/QUOTE]
Using my earlier examples again...
#1 (2 dn, 0 up) will make the engine work harder, will keep a higher top speed, and as mentioned by F4irider, will cause more stress to the chain and sprockets.
#2 (0 dn, 6 up) will be easier on the engine than stock, will significantly decrease top speed, will cause less stress to the chain and sprockets.
for slow stuff, dropping the front wil make throttle response more 'twitchy', where less in the front and more in the rear will make it 'smoother'
example 2: if you were to leave the front stock and go up 6 in the rear, again it would not give you equal results to 2 down in front.- your top speed will reduce because the wheel cannot rotate as fast anymore and the rpm at which your powerband kicks in will be reached at a slower travel speed.
either way or a combination of the two ways will make wheelies easier, but i belive that they yeild different effects/results.[/QUOTE]
Using my earlier examples again...
#1 (2 dn, 0 up) will make the engine work harder, will keep a higher top speed, and as mentioned by F4irider, will cause more stress to the chain and sprockets.
#2 (0 dn, 6 up) will be easier on the engine than stock, will significantly decrease top speed, will cause less stress to the chain and sprockets.
for slow stuff, dropping the front wil make throttle response more 'twitchy', where less in the front and more in the rear will make it 'smoother'
11-23-2004, 02:10 PM
#25
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Join Date: Aug 2004
Location: fort collins, co
Age: 44
Posts: 43
Re: 1 down = ?
the sprocket ratios are exactly that (ratios) you take the large sprocket divided by the small sprocket. it is very simple. the only thing that matters is the RATIO. changing either sprocket to produce the same ratio will produce exactly the same result (top speed and torque multiplication), except for miniscule differences in weight. the only reason a smaller front will cause more wear is the chain has to wrap around a smaller sprocket and will cause more and faster chain flex. Its just like putting gears in a car changing the ratio but no-one ever thinks about it the same way in a car because the gears are hidden, but a higher ratio improves acceleration and reduces top speed period.
for those who sa they saw a difference between 3 up and 1 down do the calculations of the two different sprocket sets and you will probably find the ratios were not exactly the same
2003 gsxr 1000--------------------- 12250rpm in 6th
stock 17 42 = 2.47----------------- 194.1mph
1down 16 42 = 2.625-------------- 182.7mph
3up 17 45 = 2.647---------------- 181.2mph
huge 16 70 = 4.375---------------- 109.6mph
thats pretty close as are most rules of thumb but not exact. with other bikes the difference can be even greater.
if you want to know in more detail what a gearing change will do just make a excell spreadsheet and calculate the speed to rpm for you bike. you will need the primary reduction, tire diameter, gear ratios and make the sprocket ratio adjustable. then you can tell exactly how fast you are going in a gear at any rpm with any sprocket ratio.
for those who sa they saw a difference between 3 up and 1 down do the calculations of the two different sprocket sets and you will probably find the ratios were not exactly the same
2003 gsxr 1000--------------------- 12250rpm in 6th
stock 17 42 = 2.47----------------- 194.1mph
1down 16 42 = 2.625-------------- 182.7mph
3up 17 45 = 2.647---------------- 181.2mph
huge 16 70 = 4.375---------------- 109.6mph
thats pretty close as are most rules of thumb but not exact. with other bikes the difference can be even greater.
if you want to know in more detail what a gearing change will do just make a excell spreadsheet and calculate the speed to rpm for you bike. you will need the primary reduction, tire diameter, gear ratios and make the sprocket ratio adjustable. then you can tell exactly how fast you are going in a gear at any rpm with any sprocket ratio.
11-23-2004, 05:03 PM
#27
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Join Date: Mar 2003
Location: San Diego, CA
Posts: 784
Re: 1 down = ?
Ok, this thread made me research it and is making me change my input.
If final drive ratio is the same, then all results are the same.
There is actually an advantage to having a larger front sprocket in that the engine has more leverage to turn the chain and so effectively has more torque with a larger front.
The disadvantages to going down much in the front is that the engine works harder (as stated before) and there is more stress to the chain trying to go around a smaller diameter...also if you go too small, the chain willl rub on the swingarm.
So bottom line is that it is better to go up in the back. If you go really big in the back and still need more, then drop one in the front.
If final drive ratio is the same, then all results are the same.
There is actually an advantage to having a larger front sprocket in that the engine has more leverage to turn the chain and so effectively has more torque with a larger front.
The disadvantages to going down much in the front is that the engine works harder (as stated before) and there is more stress to the chain trying to go around a smaller diameter...also if you go too small, the chain willl rub on the swingarm.
So bottom line is that it is better to go up in the back. If you go really big in the back and still need more, then drop one in the front.
11-24-2004, 07:46 AM
#28
Registered User
Thread Starter
Join Date: Nov 2003
Location: RACINE, WI
Age: 45
Posts: 373
Re: 1 down = ?
Originally Posted by SIC GSXR
Ok, this thread made me research it and is making me change my input.
If final drive ratio is the same, then all results are the same.
There is actually an advantage to having a larger front sprocket in that the engine has more leverage to turn the chain and so effectively has more torque with a larger front.
The disadvantages to going down much in the front is that the engine works harder (as stated before) and there is more stress to the chain trying to go around a smaller diameter...also if you go too small, the chain willl rub on the swingarm.
So bottom line is that it is better to go up in the back. If you go really big in the back and still need more, then drop one in the front.
If final drive ratio is the same, then all results are the same.
There is actually an advantage to having a larger front sprocket in that the engine has more leverage to turn the chain and so effectively has more torque with a larger front.
The disadvantages to going down much in the front is that the engine works harder (as stated before) and there is more stress to the chain trying to go around a smaller diameter...also if you go too small, the chain willl rub on the swingarm.
So bottom line is that it is better to go up in the back. If you go really big in the back and still need more, then drop one in the front.
