concours
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Straight cut gears, and chains, pretty efficient, compared to some.It's usually thought to be a percentage especially when RPM is a factor. Even so 5HP is almost 10% on the 56 HP cited above.
Straight cut gears, and chains, pretty efficient, compared to some.It's usually thought to be a percentage especially when RPM is a factor. Even so 5HP is almost 10% on the 56 HP cited above.
I like your figure better, when I last dyno’d it, it was 65rwhp… so that means it’s around 81 at the crank.It's usually thought to be a percentage especially when RPM is a factor. Even so 5HP is almost 10% on the 56 HP cited above.
Not all dynos have the same loss factor either. A 350 HP 5.7 Gen III Hemi would pull about 180 RWHP on a Dynojet dyno but only around 245 HP on a Mustang dyno. They used different methods of resistance.I like your figure better, when I last dyno’d it, it was 65rwhp… so that means it’s around 81 at the crank.
Sweet !
I like to cruise about 75 MPH. It won't get you a ticket normally and it eats the miles up.I use gearing equivalent to a 22 tooth sprocket on my 850. I ride mainly two up, and we have use it a lot for long trips. It works great set up that way. I also ride to work and ride in traffic. You will not find first gear to tall. Around town often you are in third. I suppose that might cause gearbox wear, but I have not had any problems in about 25000 miles. I guess if for some reason you never wanted to go more than 60 MPH the lower gearing would be OK. I prefer to be able to use lower revs on the highway. I think if I didn't ride two up all the time I might even put a 23 tooth sprocket on.
What size rubber do you have on back? It seems curious that nobody has addressed tire size in effective gearing. A 22t with my 18" rubber is very close to a 21t with a 19" tire on the back.No cruising here above 70mph and that only on twin highway … I tried a 22T only briefly as made the combat feel a bit sluggish , next was 21T which was perfect for my type of riding , always lots left at right wrist when I gad the urge …maybe just kinda try a few different T counts and decide what best for you , have fun experimenting !
And you bare riding a 750 Combat, not an 850 MK II.No cruising here above 70mph and that only on twin highway … I tried a 22T only briefly as made the combat feel a bit sluggish , next was 21T which was perfect for my type of riding , always lots left at right wrist when I gad the urge …maybe just kinda try a few different T counts and decide what best for you , have fun experimenting !
On the uncrowded highways where I live I will seldom be riding under 60 MPH.I think it a personal preference... 22t saves hassle when changing chains...but the downside is the torque loading from low engine revs.. The hooligan me liked seeing 70odd mph in 2nd and the noise on full shout as well as the ability to cruise in the 90s but on todays crowded and over policed roads it all seems a bit passe . If it were not such a hassle to take the primary drive off, would probably go back to 19 t
If it were me I would set it up for the best fuel economy especially living in rural area.Here's my reasoning:
First of all I live in a rural area about halfway across the Northern tier on New York State. Riding in traffic will be brief, perhaps less than 10% of my riding. I live on the Northern edge of the Adirondack Park.
Second, I want a good highway bike that will also be fun in the twisties. A dual purpose machine so to speak.
Third, I have found that lower gearing can have a "placebo affect'. All the noise and fury gives the elusion of greatly increased acceleration when sometimes, that is not really the case. In fact, too low (numerically high) gearing can actually have a negative effect on acceleration once out of the hole. It all depends on the torque curve.
Last, I have a 110/90 X 18 rear tire that is almost 2% smaller than the stock 19" rubber, so increasing the sprocket tooth count by 5% wont have a significant affect on acceleration but will reduce RPM somewhat..
Here are some screen shots of the various combination. Let's concentrate on the 3500 - 4500 RPM range.
1: Stock 21t with 19" rubber
3500 RPM in 4th = about 64 MPH, not bad.
2: Current gearing 21t with 18" rubber
3500 RPM in 4th now equals just over 61 MPH. heading in the wrong direction IMO
3: Custom gearing 22t with 18: rubber
Now we are doing just over 64 MPH at 3500 RPM, just a bit more than stock. For every 500 RPM the speed in 4th increase by just over 9 MPH so 75 MPH will be at just a little over 4000 RPM and 80 MPH will be attained with less than 4500 RPM. 3rd gear ought to be a hoot for overtaking.
So given the fact that I have 18" rear rubber, my riding style and the environment I will be riding in I think adding a tooth to the gearbox sprocket to be worthwhile, especially since I already have the gearbox exposed.
I'd be careful if I were you, The OP might get upset that you're draining his thread!Yes I know. It is so colorful and funny.
Reminds me of the days when I hunted deer and small game almost exclusively with tradition muzzle loading rifles and shotguns. I called breech loaders "suppository guns" as you loaded them by sticking something in their backside.
I think the 22t will be a good compromise. 3000 RPM at 55 MPH, 75 MPH cruise at just over 4000. And I think acceleration will be better than smaller sprockets under many conditions. A 22t in 3rd will out accelerate a 20t in 4th.If it were me I would set it up for the best fuel economy especially living in rural area.
I am the OP.I'd be careful if I were you, The OP might get upset that you're draining his thread!
Which was my point - dig, dig!I am the OP.
That pretty much says it all then.On the uncrowded highways where I live I will seldom be riding under 60 MPH.
On the uncrowded highways where I live I will seldom be riding under 60 MPH.
60 MPH on my rubber with a 22t sprocket should have me at about 3300 RPM. I can overtake in 4th but I like kicking down into "passing gear" for a more spirited experience. Should put me just over 4000 RPM when I drop to 3rd.That pretty much says it all then.