What's your favorite speed?
Club Member
Joined: Jan 2005
Posts: 1,633
Likes: 54
From: GA
RE: What's your favorite speed?
ORIGINAL: warren888
No offense to Doug, but I disagree re: RPM at 70 mph on an '06 lowrider.
Here is the math (but it really depends on your particular tire size)
On both '06 and '07, stock rear tire is 160/70. That means 160 mm tread width, and sidewall is 70% of treadwidth.
That means 16" rear wheel with tire has an actual diameter of 24.82 inches (16+ sidewall*2) ... and sidewall = 160*0.7/25.4 (convert mm to inches)
Now, overall drive ratio of highest gearare as follows (according to other posts on the forums):
2005 (5th) = 3.15
2006 (6th) = 2.96
2007 (6th) = 2.79
If you do the math - circumference of tire = pi * D = 3.14 * 24.82 inches = 77.97 inches
At 70 mph = 70*5280*12 = 4435200 inches per hour
That translates into 4435200 / 77.97 = 56883 revolutions per hour, or 948 revolutions per minute
However, 05 had a 150/80 tire I believe (different circumference).
Given the overall drive ratios above and the different tire sizes, that means the following RPM level at 70 mph for different years
2005: 2912 (with 150/80 tire)
2006: 2806 (with 160/70 tire)
2007: 2645 (with 160/70 tire)
BUt ... after all of this, was just looking at the Dunlop web site.
They claim: 150/80 tire is 25.25 inches in diameter
160/70 tire is 25.80 inches in diameter (which doesn't make sense to me)
If you use these number, then RPM@70 mphare:
2005: 2935 (with 150/80 tire)
2006: 2700(with 160/70 tire)
2007: 2544 (with 160/70 tire)
ORIGINAL: cadillac
Ive seen similar posts about this and wondered. My 2000 FXDS is turning 3000 rpm at 70 mph. And you are right about the purring.. what a groove! But I would have thought the difference between a 6 speed and 5 speed would be greater. Internally by bike engine is factory.. just added Thunderheader and SE Stage 1 kit. Dont mean to hijack the thread but I was just wondering.
bob
Ive seen similar posts about this and wondered. My 2000 FXDS is turning 3000 rpm at 70 mph. And you are right about the purring.. what a groove! But I would have thought the difference between a 6 speed and 5 speed would be greater. Internally by bike engine is factory.. just added Thunderheader and SE Stage 1 kit. Dont mean to hijack the thread but I was just wondering.
bob
Here is the math (but it really depends on your particular tire size)
On both '06 and '07, stock rear tire is 160/70. That means 160 mm tread width, and sidewall is 70% of treadwidth.
That means 16" rear wheel with tire has an actual diameter of 24.82 inches (16+ sidewall*2) ... and sidewall = 160*0.7/25.4 (convert mm to inches)
Now, overall drive ratio of highest gearare as follows (according to other posts on the forums):
2005 (5th) = 3.15
2006 (6th) = 2.96
2007 (6th) = 2.79
If you do the math - circumference of tire = pi * D = 3.14 * 24.82 inches = 77.97 inches
At 70 mph = 70*5280*12 = 4435200 inches per hour
That translates into 4435200 / 77.97 = 56883 revolutions per hour, or 948 revolutions per minute
However, 05 had a 150/80 tire I believe (different circumference).
Given the overall drive ratios above and the different tire sizes, that means the following RPM level at 70 mph for different years
2005: 2912 (with 150/80 tire)
2006: 2806 (with 160/70 tire)
2007: 2645 (with 160/70 tire)
BUt ... after all of this, was just looking at the Dunlop web site.
They claim: 150/80 tire is 25.25 inches in diameter
160/70 tire is 25.80 inches in diameter (which doesn't make sense to me)
If you use these number, then RPM@70 mphare:
2005: 2935 (with 150/80 tire)
2006: 2700(with 160/70 tire)
2007: 2544 (with 160/70 tire)
I like to ride faster than you...whoever you is.
Seriously though, I ride to the rpms more so than the speed I guess. In other words, if I could have only one gauge, I would choose the rpm gauge. In the twisties, I keep the bike around the 3500 - 4500rpm range and when cruising on back roads, closer to 2000 - 2500. In the twisties, I want instant revving action and my bike responds well in the upper ranges. I absolutely love to come out of a sharp turn at35 in second and wind through the gears WOT.
Account Suspended
Joined: Aug 2006
Posts: 399
Likes: 2
From: Orange County, CA
RE: What's your favorite speed?
ORIGINAL: Dynamite
Can someone please stick pins in my eyes so I don't have to see this rediculous outlay of digital black ink. Nobody asked for a freakin math lesson or what ever study the above litany applies to.
I like to ride faster than you...whoever you is. Seriously though, I ride to the rpms more so than the speed I guess. In other words, if I could have only one gauge, I would choose the rpm gauge. In the twisties, I keep the bike around the 3500 - 4500rpm range and when cruising on back roads, closer to 2000 - 2500. In the twisties, I want instant revving action and my bike responds well in the upper ranges. I absolutely love to come out of a sharp turn at35 in second and wind through the gears WOT.
Can someone please stick pins in my eyes so I don't have to see this rediculous outlay of digital black ink. Nobody asked for a freakin math lesson or what ever study the above litany applies to.
I like to ride faster than you...whoever you is.
Seriously though, I ride to the rpms more so than the speed I guess. In other words, if I could have only one gauge, I would choose the rpm gauge. In the twisties, I keep the bike around the 3500 - 4500rpm range and when cruising on back roads, closer to 2000 - 2500. In the twisties, I want instant revving action and my bike responds well in the upper ranges. I absolutely love to come out of a sharp turn at35 in second and wind through the gears WOT.
Actually, I was interested because I've heard a lot of discussion about the effect of the 6 speed introduced in 2006 vs. the 5 speed previously. There is relatively little RPM difference as you can see (although more so in '07). The gear ratios of the tranny end up the same in top gear, but thefinal drive ratio has changed each year. So the math stuff was really just an interest in getting the detail about the differences between years.
I am curious about these low RPM ranges (2000-2500). I sometimes find myself riding in the lower end (2200-2400 RPM), but I am concerned about lugging the engine at that RPM. I find anything below 2500 doesn't feel right on the engine, but not sure if that is just my imagination.
Road Warrior
Joined: Jul 2006
Posts: 1,308
Likes: 0
From: Detroit
RE: What's your favorite speed?
highway 65-70 but i hate getin tailgated... i like 45-55 on the backroads when i can enjoy my ride without traffic. makes me wish i lived in a rural area sometimes when i get out into the sticks and dont see a car for miles..... of course id always be later for work everyday more then i already am....
Intermediate
Joined: May 2007
Posts: 27
Likes: 0
From: Sedro Woolley, Wa.
RE: What's your favorite speed?
ORIGINAL: Dynamite
[sm=icon_stickpoke.gif]
[sm=icon_stickpoke.gif]
Club Member
Joined: Jan 2005
Posts: 1,633
Likes: 54
From: GA
RE: What's your favorite speed?
Thanks! I have enjoyed getting it where it is, but my wallet doesn't thank me. I have it just about where I want it, but can't decide on a chrome front end. The delima is does the $ to do it = the look I will get.
Thread de-hijacked!
Warren888 I do have a math phobia but I did surprisingly well inCollege...we won't discuss high school. I can appreciate analytical personalities, it was just an easy target.
Thread de-hijacked!
Warren888 I do have a math phobia but I did surprisingly well inCollege...we won't discuss high school. I can appreciate analytical personalities, it was just an easy target.
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Account Suspended
Joined: Aug 2006
Posts: 399
Likes: 2
From: Orange County, CA
RE: What's your favorite speed?
ORIGINAL: Dynamite
Warren888 I do have a math phobia but I did surprisingly well inCollege...we won't discuss high school. I can appreciate analytical personalities, it was just an easy target.
Warren888 I do have a math phobia but I did surprisingly well inCollege...we won't discuss high school. I can appreciate analytical personalities, it was just an easy target.
I agree with 13A77 btw, love the paint job on your bike. Looks great!