6-speed
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: 6-speed
ORIGINAL: pococj
You might not like the messengers, but factor out personalities, and let the actual facts speak for themselves.
You might not like the messengers, but factor out personalities, and let the actual facts speak for themselves.
ORIGINAL: pococj
What I found was that straight cut gears are noisier, more efficient power transmitters, and are generally considered stronger, with a caveat attached to the strength part. That caveat is that a helical gear set can be stronger, but only because there are more teeth, thus more surface area, engaged at any one time. But this isn't always the case, due to physical size limitations in some applications. I also found that helical gears transmit axial thrust. That is, in operation they try to move away from each other, and this means they thrust against one of the support bearings. This results in the requirement for a bearing that resists thrust as well as supports the shaft, and also results in a necessary increase in the bearing housing size and/or strength to support the bearing.
I found that usually a manufacturer will choose the helical bearing for the noise reduction aspect, and this is often driven by the EPA, and OSHA, depending upon applications. After choosing the helical gear, the manufacturer specs it out, and can generally get by with using a lesser quality material for the same loading, because of the increase in the number of teeth engaged, spreading the forces out over a larger area. Then he must lose some of his savings by specifying the more expensive bearing(s), and by designing the casing or housing to withstand the increased axial thrust.
All this stuff has been presented in this thread. It ain't made up out of nothing, but is easily verified if someone is willing to do the research.
What I found was that straight cut gears are noisier, more efficient power transmitters, and are generally considered stronger, with a caveat attached to the strength part. That caveat is that a helical gear set can be stronger, but only because there are more teeth, thus more surface area, engaged at any one time. But this isn't always the case, due to physical size limitations in some applications. I also found that helical gears transmit axial thrust. That is, in operation they try to move away from each other, and this means they thrust against one of the support bearings. This results in the requirement for a bearing that resists thrust as well as supports the shaft, and also results in a necessary increase in the bearing housing size and/or strength to support the bearing.
I found that usually a manufacturer will choose the helical bearing for the noise reduction aspect, and this is often driven by the EPA, and OSHA, depending upon applications. After choosing the helical gear, the manufacturer specs it out, and can generally get by with using a lesser quality material for the same loading, because of the increase in the number of teeth engaged, spreading the forces out over a larger area. Then he must lose some of his savings by specifying the more expensive bearing(s), and by designing the casing or housing to withstand the increased axial thrust.
All this stuff has been presented in this thread. It ain't made up out of nothing, but is easily verified if someone is willing to do the research.
Thread Starter
|
Novice
Joined: Dec 2005
Posts: 15
Likes: 0
From:
RE: 6-speed
There have been some great responses here. It seems Harley has played around quite a bit with different bearings. As someone who has done a bit of high performance work on cars, including engine rebuilds, I totally understand the importance of the internals and the bottom end of a V-Twin. Cams, heads, top end can all be changed alot easier than bottom end components.
There has also been alot of talk about the gear ratios. The Harley website posts very different "Gear Ratio (overall)" figures for the 5-speed and 6-speed. Are these ratios reflecting some other changes, besides the transmission? The 5-speed ratios don't seem right to me.
6-speed:
1st 3.337
2nd 2.313
3rd 1.718
4th 1.391
5th 1.175
6th 1.000
5-speed:
1st 10.110
2nd 6.958
3rd 4.953
4th 3.862
5th 3.150
There has also been alot of talk about the gear ratios. The Harley website posts very different "Gear Ratio (overall)" figures for the 5-speed and 6-speed. Are these ratios reflecting some other changes, besides the transmission? The 5-speed ratios don't seem right to me.
6-speed:
1st 3.337
2nd 2.313
3rd 1.718
4th 1.391
5th 1.175
6th 1.000
5-speed:
1st 10.110
2nd 6.958
3rd 4.953
4th 3.862
5th 3.150
Advanced
Joined: Oct 2005
Posts: 79
Likes: 1
From:
RE: 6-speed
ORIGINAL: ChromeScoot
There have been some great responses here. It seems Harley has played around quite a bit with different bearings. As someone who has done a bit of high performance work on cars, including engine rebuilds, I totally understand the importance of the internals and the bottom end of a V-Twin. Cams, heads, top end can all be changed alot easier than bottom end components.
There has also been alot of talk about the gear ratios. The Harley website posts very different "Gear Ratio (overall)" figures for the 5-speed and 6-speed. Are these ratios reflecting some other changes, besides the transmission? The 5-speed ratios don't seem right to me.
6-speed:
1st 3.337
2nd 2.313
3rd 1.718
4th 1.391
5th 1.175
6th 1.000
5-speed:
1st 10.110
2nd 6.958
3rd 4.953
4th 3.862
5th 3.150
There have been some great responses here. It seems Harley has played around quite a bit with different bearings. As someone who has done a bit of high performance work on cars, including engine rebuilds, I totally understand the importance of the internals and the bottom end of a V-Twin. Cams, heads, top end can all be changed alot easier than bottom end components.
There has also been alot of talk about the gear ratios. The Harley website posts very different "Gear Ratio (overall)" figures for the 5-speed and 6-speed. Are these ratios reflecting some other changes, besides the transmission? The 5-speed ratios don't seem right to me.
6-speed:
1st 3.337
2nd 2.313
3rd 1.718
4th 1.391
5th 1.175
6th 1.000
5-speed:
1st 10.110
2nd 6.958
3rd 4.953
4th 3.862
5th 3.150
1st 9.878
2nd 6.846
3rd 5.085
4th 4.112
5th 3.478
6th 2.96
These seem more similar to the 5 speed ratios.
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: 6-speed
OK, Jamie, well its well known by now that your my biggest fan. Just by posting what you did below, its obvious you skipped alot of what myself and others have posted so do us a big favor, put the big walking stick down and read through thoroughly with proper insight.
This whole paragraph is nothing more than your opinion. You feel there is no reason to bash the 6 speed, but I think differently than you. Facts make me question(NOT BASH)the long term durability of the new 6 speed.
A. Buyer must sign waiver form. Since when has anyone ever had to sign a waiverform when buying a HD bike ever in the past?
B. Bearing will be replaced free of charged by a dealership every 15k miles. Since when has any HD transmission ever needed this type of service to be done on a regular basis?
C. H-D is in its first generation of transmissions using helical cut gears in some of their bikes including the new Dyna, and the 06' Sporty.
D. Already one recall on a safety issue with the new transmission in which people were HURT.
I myself LOGICALLY take A,B,C, and D along with a strong understanding of how implementing a style of gears(to HD anyway)can cause problems or potential future problems with the transmission. Now I never said the new transmission is "no good" in the same sense your trying to paint, but I am smart enough to know that the new transmission has issues that are NOT YET worked out. So you hate the pool of info become tainted? Then look at the real situation with open eyes instead of someone who obvious owns the product and feels the need to defend it at every turn because he feels it infringes on his buying decision.
Well, glad to see you did some research. And what you said here is correct. Guess what? I have been stating the same thing since day 1.
This is a mythical number that nobody seems to know what it really means. Ive made a number of calls,probably a couple dozen and I have gotten a couple dozen DIFFERENT answers back from various people who work for HD, and those who supply parts to HD, and those who make aftermarket parts for HD bikes. HD is very vague on what 28% torque capacity means. It could mean the transmission case is 28% stonger, it could mean the shaft bearings carry a 28% higher rad
ORIGINAL: JamieWG
First off, I apologize if my posts have offended anyone. I feel there is no reason to bash the new 6-speed and it annoys me when I read misinformation being spread here (what I consider to be misinformation). When it comes to HDs, I've found this forum to be the best source of knowledge on the net. I hate to see that pool of info become tainted. If someone has the opinion that the new 6-speed is no good, I've got no problem with that. When they make statements that are unfounded, I get riled up. In the future I will no longer respond.
First off, I apologize if my posts have offended anyone. I feel there is no reason to bash the new 6-speed and it annoys me when I read misinformation being spread here (what I consider to be misinformation). When it comes to HDs, I've found this forum to be the best source of knowledge on the net. I hate to see that pool of info become tainted. If someone has the opinion that the new 6-speed is no good, I've got no problem with that. When they make statements that are unfounded, I get riled up. In the future I will no longer respond.
A. Buyer must sign waiver form. Since when has anyone ever had to sign a waiverform when buying a HD bike ever in the past?
B. Bearing will be replaced free of charged by a dealership every 15k miles. Since when has any HD transmission ever needed this type of service to be done on a regular basis?
C. H-D is in its first generation of transmissions using helical cut gears in some of their bikes including the new Dyna, and the 06' Sporty.
D. Already one recall on a safety issue with the new transmission in which people were HURT.
I myself LOGICALLY take A,B,C, and D along with a strong understanding of how implementing a style of gears(to HD anyway)can cause problems or potential future problems with the transmission. Now I never said the new transmission is "no good" in the same sense your trying to paint, but I am smart enough to know that the new transmission has issues that are NOT YET worked out. So you hate the pool of info become tainted? Then look at the real situation with open eyes instead of someone who obvious owns the product and feels the need to defend it at every turn because he feels it infringes on his buying decision.
ORIGINAL: JamieWG Before I bought my bike I did some research on the 6-speed. It was all done on the net, and if you want to learn about gears, you can do it too. Here is what I learned - When straight cut gears are engaged, all forces are applied to one tooth on each gear. When helical cut gears are engaged, depending on the angle of the teeth, the forces are distributed between 1.2 - 1.9 teeth per gear. This means, given equal materials, the helical cut gears can carry a heavier load. The trade off for that extra strength is thrust loads. The gears try to move away from each other, sort of like a screw turning out of a bolt. Helical cut gears are also quieter and the general consensus seems to be that they provide smoother shifting.
ORIGINAL: JamieWG HD states the new 6-speed is able to carry 28% more torque than previous transmissions. I don't know what kind of steel the new gears are made of, but considering that helical cut gears have more than one tooth engaged, plus, the cases were beefed up to handle the additional thrust loads, I see no reason to doubt the 28% claim.
Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: 6-speed
ORIGINAL: ChromeScoot
There have been some great responses here. It seems Harley has played around quite a bit with different bearings. As someone who has done a bit of high performance work on cars, including engine rebuilds, I totally understand the importance of the internals and the bottom end of a V-Twin. Cams, heads, top end can all be changed alot easier than bottom end components.
There has also been alot of talk about the gear ratios. The Harley website posts very different "Gear Ratio (overall)" figures for the 5-speed and 6-speed. Are these ratios reflecting some other changes, besides the transmission? The 5-speed ratios don't seem right to me.
6-speed:
1st 3.337
2nd 2.313
3rd 1.718
4th 1.391
5th 1.175
6th 1.000
5-speed:
1st 10.110
2nd 6.958
3rd 4.953
4th 3.862
5th 3.150
There have been some great responses here. It seems Harley has played around quite a bit with different bearings. As someone who has done a bit of high performance work on cars, including engine rebuilds, I totally understand the importance of the internals and the bottom end of a V-Twin. Cams, heads, top end can all be changed alot easier than bottom end components.
There has also been alot of talk about the gear ratios. The Harley website posts very different "Gear Ratio (overall)" figures for the 5-speed and 6-speed. Are these ratios reflecting some other changes, besides the transmission? The 5-speed ratios don't seem right to me.
6-speed:
1st 3.337
2nd 2.313
3rd 1.718
4th 1.391
5th 1.175
6th 1.000
5-speed:
1st 10.110
2nd 6.958
3rd 4.953
4th 3.862
5th 3.150
5 speed values for 03' and up stock:
1st 3.21:1
2nd 2.21:1
3rd 1.57:1
4th 1.23:1
5th 1:1
6 speed "Screamin Eagle"
1st 3.21:1
2nd 2.21:1
3rd 1.57:1
4th: 1.23:1
5th 1:1
6th .89:1
6 speed "cruise drive":
1st 3.34:1
2nd 2.31:1
3rd 1.72:1
4th 1.39:1
5th 1.18:1
6th 1:1
Picture getting a little clearer yet folks?
Advanced
Joined: Oct 2005
Posts: 79
Likes: 1
From:
RE: 6-speed
The picture is fuzzy and getting fuzzier.
If the old 5 speed had a final of 1:1 and the cruise drive 6 speed has a final of 1:1, how does the new 6 speed drop the revs by 200 rpm at 70 mph vs the old 5 spd? And where did you get your figures? The figures I found were in line with Chrome Scoot's
If the old 5 speed had a final of 1:1 and the cruise drive 6 speed has a final of 1:1, how does the new 6 speed drop the revs by 200 rpm at 70 mph vs the old 5 spd? And where did you get your figures? The figures I found were in line with Chrome Scoot's
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Banned
Joined: Nov 2005
Posts: 802
Likes: 3
From:
RE: 6-speed
ORIGINAL: ItsaHarley
The picture is fuzzy and getting fuzzier.
If the old 5 speed had a final of 1:1 and the cruise drive 6 speed has a final of 1:1, how does the new 6 speed drop the revs by 200 rpm at 70 mph vs the old 5 spd? And where did you get your figures? The figures I found were in line with Chrome Scoot's
The picture is fuzzy and getting fuzzier.
If the old 5 speed had a final of 1:1 and the cruise drive 6 speed has a final of 1:1, how does the new 6 speed drop the revs by 200 rpm at 70 mph vs the old 5 spd? And where did you get your figures? The figures I found were in line with Chrome Scoot's
HD regeared the primary(the compensator sprocket and clutch basket both use different amounts of teeth)drive to allow the engine to turn less rpms in its 6th gear. In reality if someone had a 5 speed and they didnt want to buy a 6 speed, they could change the primary gearing to lower their engine rpms in 5th gear if they wanted to. Though the bike would probably be pretty sluggish off the line if the engine was stock with no power upgrades.
I actually did that with my current project, but I went the other way in the gearing( I wanted to improve low end acceleration instead of lower rpm's in 5th gear since I was adding an overdrive 6th gear). I wanted to improve low end acceleration in my bike, so I took my stock 3.15(25 tooth compensator sprocket, 36 tooth clutch basket) gear setup, and changed the primary gear setup to give me a 3.37(24 tooth compensator,37 tooth clutch basket)gearing which helps significantly in off the line acceleration. Now, at the same time I also increased the rpms the engine would be running in 5th gear, but thats what I wanted since I now have an overdriven 6th gear setup. So 1-5 gears in myself will be geared steeper for better acceleration and more torque for performance, while the 6th gear will act as a cruising gear where rpms will be lowered for a more relaxed ride and for economy. And since 6th gear is under 1:1 I get the full benefit of overall lower engine rpm's as the speed increases.
Road Master
Joined: Oct 2005
Posts: 1,034
Likes: 3
From:
RE: 6-speed
ORIGINAL: MegaHDman
D. Already one recall on a safety issue with the new transmission in which people were HURT.
D. Already one recall on a safety issue with the new transmission in which people were HURT.
http://articles.news.aol.com/busines...23144209990008
ORIGINAL: MegaHDman
I myself LOGICALLY take A,B,C, and D along with a strong understanding of how implementing a style of gears(to HD anyway)can cause problems or potential future problems with the transmission. Now I never said the new transmission is "no good" in the same sense your trying to paint, but I am smart enough to know that the new transmission has issues that are NOT YET worked out. So you hate the pool of info become tainted? Then look at the real situation with open eyes instead of someone who obvious owns the product and feels the need to defend it at every turn because he feels it infringes on his buying decision.
I myself LOGICALLY take A,B,C, and D along with a strong understanding of how implementing a style of gears(to HD anyway)can cause problems or potential future problems with the transmission. Now I never said the new transmission is "no good" in the same sense your trying to paint, but I am smart enough to know that the new transmission has issues that are NOT YET worked out. So you hate the pool of info become tainted? Then look at the real situation with open eyes instead of someone who obvious owns the product and feels the need to defend it at every turn because he feels it infringes on his buying decision.
ORIGINAL: JamieWG Before I bought my bike I did some research on the 6-speed. It was all done on the net, and if you want to learn about gears, you can do it too. Here is what I learned - When straight cut gears are engaged, all forces are applied to one tooth on each gear. When helical cut gears are engaged, depending on the angle of the teeth, the forces are distributed between 1.2 - 1.9 teeth per gear. This means, given equal materials, the helical cut gears can carry a heavier load. The trade off for that extra strength is thrust loads. The gears try to move away from each other, sort of like a screw turning out of a bolt. Helical cut gears are also quieter and the general consensus seems to be that they provide smoother shifting.
ORIGINAL: MegaHDman
Well, glad to see you did some research. And what you said here is correct. Guess what? I have been stating the same thing since day 1.
Well, glad to see you did some research. And what you said here is correct. Guess what? I have been stating the same thing since day 1.
ORIGINAL: MegaHDman
This is a mythical number that nobody seems to know what it really means. Ive made a number of calls,probably a couple dozen and I have gotten a couple dozen DIFFERENT answers back from various people who work for HD, and those who supply parts to HD, and those who make aftermarket parts for HD bikes. HD is very vague on what 28% torque capacity means. It could mean the transmission case is 28% stonger, it could mean the shaft bearings carry a 28% higher radial load(or axial). It could mean some of the gears themselves are capable of carrying a larger torque carrying(twisting force)load. It could mean all of them together, or none of them.
I do know one thing, there are already parts that require replacement regularly in the transmission. So obvious the parts that need replacement CANNOT handle to new forces adequately for long duration periods. I also do know that "torque carrying capacity" has never been an issue ever in any past HD transmission. So the need to mention this to me is nothing more than a promotional tool for HD on the launch of the redesigned Dyna bike.
This is a mythical number that nobody seems to know what it really means. Ive made a number of calls,probably a couple dozen and I have gotten a couple dozen DIFFERENT answers back from various people who work for HD, and those who supply parts to HD, and those who make aftermarket parts for HD bikes. HD is very vague on what 28% torque capacity means. It could mean the transmission case is 28% stonger, it could mean the shaft bearings carry a 28% higher radial load(or axial). It could mean some of the gears themselves are capable of carrying a larger torque carrying(twisting force)load. It could mean all of them together, or none of them.
I do know one thing, there are already parts that require replacement regularly in the transmission. So obvious the parts that need replacement CANNOT handle to new forces adequately for long duration periods. I also do know that "torque carrying capacity" has never been an issue ever in any past HD transmission. So the need to mention this to me is nothing more than a promotional tool for HD on the launch of the redesigned Dyna bike.