In search of taller gearing for v-11 sport

[Murray]

Rather than messing with crown wheel and pinions would it be easier to get a gear set for 6th custom made and put in your box ie further overdrive it. So you still have the round town flexabilty but top is a high speed long haul gear you'll probally also have to adjust the speed you shift into top to say minium 100mph.

 

MGS gearing is seriously tall I dunno how Gyles gets on with standing starts but it would be pretty tricky IMO. The 1100 sport is hard enough to get off the line in a hurry cleanly.

[Guest ratchethack]

Somebody correct me if I'm wrong, (too lazy to check) but at 73 mph in 6th, you're (if I'm not mistaken?) at about 4300 RPM or thereabouts? This puts your motor in the "hole" in the torque curve, where it's developing somewhere less than 40 lbs./ft. (and only at WOT) -- towing a 550 lb. Guzzi plus y'er own contributions to gravity and mass against the wind blast?? Now this is just me, but I seldom even consider using 6th until 80 at the very least (maybe less on a downhill and/or with a tailwind), and almost NEVER on much of an uphill pull, well above 80. Just out o' sheer kindness -- as any Gent should his best Gal.

 

But o' course. . . (well, you know).

[Ryland3210]

Somebody correct me if I'm wrong, (too lazy to check) but at 73 mph in 6th, you're (if I'm not mistaken?) at about 4300 RPM or thereabouts? This puts your motor in the "hole" in the torque curve, where it's developing somewhere less than 40 lbs./ft. -- towing a 550 lb. Guzzi plus y'er own contribution against the wind blast?? Now this is just me, but I never even consider using 6th until 80 at the very least, and NEVER on an uphill pull, well above that. Just out o' sheer kindness -- as any Gent should his best Gal.

 

But o' course. . . (well, you know).

 

My bike runs about 60 mph at 3,000 RPM, from recollection. If so, at 73 it's doing 3650.

 

My philosophy is somewhat different from yours and Murray's (except I think he missed my earlier post suggesting changing the 6th gearset ratio). I don't feel the need to keep the RPM's in a range that allows turning up the wick for instant torque reserve when I'm spending lots of time on the slab at a constant 73. I believe in the best maintenance and tuning as my form of TLC, but happy to run the engine at lower RPM with taller gears, as long as they are high enough to maintain decent oil pressure.

 

I come from a background when Honda's big engine was the 450, and I did everything practical to change the primary and final drive ratios on my Harley to drop the RPM's. With wife in the sidecar and vacation and overnight camping gear on board, I would lug that 1200 cc beast up long hills in top gear with wide open throttle whenever necessary, and only downshifted when it wouldn't hold 55. I had designed a diagnostic panel for it which had an LED energized by the points on each cylinder. You could practically count the pulses. On another 10,500 mile trip across the country, down to Mexico and back in July, I did the same thing with my Honda 450, fully loaded with wife, full camping gear, etc. Neither engine showed any signs of harm.

 

When I learned that Mercruiser's V8 engines were purchased from the same assembly line GM used for cars, I gained a great deal of confidence in the basic ability of piston engines to be able to run long term at much higher loads than they encounter on cars and bikes. Mercruiser simply made the changes to "marinize" the automobile engines.

 

I might be missing something about the idiosyncracies of Guzzi engines, but I suspect that they are just as robust, based on comments from people like Pete Roper and others.

[Skeeve]

I thought you just came out of a deep sleep or something.

 

Just call me "Rip van Skeevenkle..."

[Skeeve]

Smells like a troll to me...

 

A stock V11 isn't going to be able to pull much more gear than it has.

 

The Sport 1100 is geared a little taller, for something like 150mph, and can't pull it.

 

145mph at just under redline is what they'll do.

 

Unless a person is running at someplace like Daytona, that kind of top speed is hypothetical anyway.

 

I suspect that much of this discussion is of the hypothetical, purely-for-the-Bonneville-LSR-group sort. So in that regard, you're entirely correct, & I don't plan on changing anything either!

[Murray]

The 1100 sports are geared for around 220-230kph (130ish mph?) and will pull near enough to reline in top just with slight breathing and exhaust mods (haven't tried it on a dead stock one). Daytona's AFAIK have the same gearing with a slightly higher redline so in theroy should be faster. Seat of the pants the MGS is significantly taller and I would say would be close to your 150 mph (250-260kph) but it also has a higher redline and more hp to push it. The V11's are somewhere in the middle of these two.

[Steve G.]

I have an inexpensive way [free] to change the ratio of your bike. Get a higher profile side wall tire, a 70 or 75% side wall.

I run with a GPS sometimes with my bike. I can confirm the Veglia speedometer reads 4 mph [6kph]optimistic pretty well from 40mph right up to the maximum it can do. At a GPS indicated 150kph, my Vegila tachometer [again taken with a grain of salt ] reads engine revs @ 5500rpm.

My personal thoughts are that the gearing is just fine. The maximum I can legally go in Canada is 110kph, and find that a fine cruising speed for this machine is a GPS indicated 125kph @ 4000rpm.

Mechanically, if you were to find a lower revving axle ratio, I think it would be harder on the gearbox bearings, which will be spinning slower, yet accepting the same output from the engine.

Steve

[dlaing]

I think some of the pre-1999 spines had 160/60 on 18inch wheels.

Converting to those might should make some difference, especially with higher profile tires, but you would have to calculate the diameter at the tire not the wheel.

The skinny tire might improve the handling, too!

Watch for fender clearance!

[rocker59]

1996 and back Spineys had a 160/60-18 rear tire and no cush drive. The tranny gears are straight-cut.

 

So enough speculation... Here are some real-deal numbers to crunch:

 

 

Here are the gear ratios straight out of my owners manuals:

 

.....................................Nero Corsa:.............Sport 1100:

 

Primary drive:.................1.16842:1.................1.3529:1

 

Gearbox:..................1st...2.4000.......................1.812

................................2nd...1.778.......................2.50

................................3rd...1.3636......................1.00

................................4th...1.1111.......................0.833

................................5th...0.9655.......................0.730

................................6th...0.8519...............................

 

Final Drive:......................2.9091.......................4.125

 

Overall ratio in top gear:...4.1737.......................4.0783

 

 

So there you have it. The Sport 1100 is geared slightly taller than the V11 Nero Corsa even though it's a gear short.

 

I can also say that neither of my two bikes likes to be in top gear below 4,000 rpm.

 

The Nero Corsa gets measurably better fuel economy on the highway at 4,500 rpm than it does at 4,000 rpm. Something like 2 to 3 mpg.

 

 

Here's the formula for figuring speed from RPM: "MPH = TIRE RADIUS ÷ 168 x ENGINE RPM ÷ GEAR RATIO"

 

Sport 1100: 145.4687 mph = 12.75 tire radius / 168 x 8,000 rpm / 4.1737 So, hypothetical top speed is 145mph at 8,000 rpm with a 160/60-18 BT-014 tire.

 

V11 LeMans: 144.7848 mph = 12.4 tire radius / 168 x 8,000 rpm / 4.0783 So, hypothetical top speed is 144mph at 8,000 rpm with a 180/55-17 BT-014 tire.

 

 

 

 

Source for formula: Edelbrock Tech Center

Source for tire specs: Bridgestone

Source for gear ratios: 1996 Sport 1100 owners manual & 2004 V11 LeMans Nero Corsa owners manual.

[Paul Minnaert]

so mine is doing 9000rpm in 6th gear, with v11 le mans gearing that makes 162 mph (261km/h), that sounds pretty fast. My own calculations were lower

[Guest ratchethack]

I can also say that neither of my two bikes likes to be in top gear below 4,000 rpm.

 

The Nero Corsa gets measurably better fuel economy on the highway at 4,500 rpm than it does at 4,000 rpm. Something like 2 to 3 mpg.

Interesting comparo there, Rocker. Your observations agree with wot I've long observed. Unlike the Motor Davidson Harley Cycle donk, with which the V11 is so often compared (and often most improperly, IMHO), the V11 has to BREATHE not only to do work (see torque curve) but to be efficient at it. A Bloat-o-Glide is far closer to agricultural equipment than the V11, IMHO, with an incredible torque curve, the likes o' which is not to be found much of anywhere in the moto world. F'er cryin' out lout, a HD can fairly easily chug away from a standing stop in 3rd gear with a little clutch slip -- like a Farmall tractor. IMHO it's easy (and mighty tempting at times, I admit!) to "lug" the V11 motor at a steady crusing speed. NOT a good idea, even when she seems willing enough to "pull" herself out without a downshift, and without complaining. IMHO she's got to be up near 5K RPM and above to run where she likes it the best -- and that includes when steadily pulling against the wind blast at anything above 70-80 mph. Climbing long uphill grades in top cog in the "torque curve hole" -- not a nice way to treat her.

 

She's got a fine set o' pipes, she wants to sing, and in our case, she's got 6 -- count 'em, SIX -- ranges to sing in! I figure long as she's got 'em -- why not let her enjoy 'em?!

 

BAA, TJM, & YMMV

[rocker59]

so mine is doing 9000rpm in 6th gear, with v11 le mans gearing that makes 162 mph (261km/h), that sounds pretty fast. My own calculations were lower

 

What formula were you using to make the calculations?

[rocker59]

Interesting comparo there, Rocker. Your observations agree with wot I've long observed. Unlike the Motor Davidson Harley Cycle donk, with which the V11 is so often compared (and often most improperly, IMHO), the V11 has to BREATHE not only to do work (see torque curve) but to be efficient at it. A Bloat-o-Glide is far closer to agricultural equipment than the V11, IMHO, with an incredible torque curve, the likes o' which is not to be found much of anywhere in the moto world. F'er cryin' out lout, a HD can fairly easily chug away from a standing stop in 3rd gear with a little clutch slip -- like a Farmall tractor. IMHO it's easy (and mighty tempting at times, I admit!) to "lug" the V11 motor at a steady crusing speed. NOT a good idea, even when she seems willing enough to "pull" herself out without a downshift, and without complaining. IMHO she's got to be up near 5K RPM and above to run where she likes it the best -- and that includes when steadily pulling against the wind blast at anything above 70-80 mph. Climing long uphill grades in top gear in the "torque curve hole" -- not a nice way to treat her.

 

She's got a fine set o' pipes, she wants to sing, and in our case, she's got 6 -- count 'em, SIX -- ranges to sing in! I figure long as she's got 'em -- why not let her enjoy em?!

 

BAA, TJM, & YMMV

 

Yep the HD and MG are completely different animals.

 

V11 = 1064cc. Bore 92mm. Stroke 80mm. It's on "oversquare" engine.

 

1200 Sportsters = 1203cc. Bore 88.90mm. Stroke 96.77mm. It's an "undersquare" engine.

 

That's part of the reason why the Sportster can get away with lugging around in top gear at 2500 - 3000 rpm and return 50mpg.

[Skeeve]

1996 and back Spineys had a 160/60-18 rear tire and no cush drive. The tranny gears are straight-cut.

 

So enough speculation... Here are some real-deal numbers to crunch:

 

 

Here are the gear ratios straight out of my owners manuals:

 

.....................................Nero Corsa:.............Sport 1100:

 

...

 

Overall ratio in top gear:...4.1737.......................4.0783

 

 

So there you have it. The Sport 1100 is geared slightly taller than the V11 Nero Corsa even though it's a gear short.

 

I can also say that neither of my two bikes likes to be in top gear below 4,000 rpm.

 

The Nero Corsa gets measurably better fuel economy on the highway at 4,500 rpm than it does at 4,000 rpm. Something like 2 to 3 mpg.

 

 

Here's the formula for figuring speed from RPM: "MPH = TIRE RADIUS ÷ 168 x ENGINE RPM ÷ GEAR RATIO"

 

Sport 1100: 145.4687 mph = 12.75 tire radius / 168 x 8,000 rpm / 4.1737 So, hypothetical top speed is 145mph at 8,000 rpm with a 160/60-18 BT-014 tire.

 

V11 LeMans: 144.7848 mph = 12.4 tire radius / 168 x 8,000 rpm / 4.0783 So, hypothetical top speed is 144mph at 8,000 rpm with a 180/55-17 BT-014 tire.

 

All well & good, & thank you very much for the hard data, and lest I sound critical w/ the next bit, let me assure you it's not intended as such in any way, I just feel that I should point out a small detail... you crossed up the overall drive ratios at the very last!

 

Easy to do in the heat of the moment; transcription errors are a particular plague of my own, so I totally understand... Let's try those calcs over, shall we?

 

Nero Corsa [17" wheel w/ lower profile but wider tire]: (12.4*8000)/(168*4.1737)= 141.5(plus many digits) = 139mph claimed top speed

Sport 1100 [18" wheel w/ narrower but taller profile tire]: (12.75*8000)/(168*4.0783)= 148.9(plus many digits) = 150mph claimed top speed

 

By "claimed top speed," I'm using figures drawn from memory that either originated w/ the moto press or with the factory. Sue me.

 

Anyway, I'd say that once the correct figures are dropped in, your (Edelbrock's) formula works out pretty close to "empirical" data.

[Skeeve]

Yep the HD and MG are completely different animals.

 

V11 = 1064cc. Bore 92mm. Stroke 80mm. It's on "oversquare" engine.

 

1200 Sportsters = 1203cc. Bore 88.90mm. Stroke 96.77mm. It's an "undersquare" engine.

 

That's part of the reason why the Sportster can get away with lugging around in top gear at 2500 - 3000 rpm and return 50mpg.

 

Only part of it. The other part would be you're quoting 883 Sportster mileage figures for the 1200!..