Early Tonti Horsepower

[swooshdave]

Its a bit of a head scratcher.   The new v9s are claimed to put out 55hp at the crank.  Yet every dyno I have seen puts them at 50-51hp to the ground?  How can that be?

That seems right. What don't you like about that?

[tpeever]

Your 850T is putting out about the same as your Commando. Superbike numbers in the day. Don't worry about it, just ride and enjoy. The fact is that 50 hp at the rear wheel is plenty to have fun with. As my Britbike buddy likes to say, "they roll down the road just fine"

[swooshdave]

Your 850T is putting out about the same as your Commando. Superbike numbers in the day. Don't worry about it, just ride and enjoy. The fact is that 50 hp at the rear wheel is plenty to have fun with. As my Britbike buddy likes to say, "they roll down the road just fine"

What I found fascinating was the numbers listed for the LeMans. They were probably that high to look similar to the 900SS.

[pete mcgee]

My LeMans 3 @ 186000 km, 180 psi compression 44 rwh, the wife's somewhat newer K75s 45rwh.
Post rebuild about 10,000 km, big bore kit, mid range cam, 210 psi compression, 60 rwh.
Why a mid range can? Because you go to jail here and they crush your bike if you are caught using it to its full "potential" plus I do a lot of mountain riding where more torque is "nice"
So Peters sieve like memory would seem to be correct.
Also every dyno will read differently on different days etc etc.
Factory horse power figures are as reliable as a politicians promises........

[Rough Edge racing]

 Ok, I ran a stripped down 85 Cali 2 at the one mile standing start LSR track in Ohio. Stock gearing and the engine was stock but no mufflers and revised carb jetting.. Made four runs between 116-117 MPH. The bike may have went a few MPH faster with a longer run.
  My 650 Triumph is a dedicated naked frame LSR bike holding a few speed records...Speeds are 125-128 MPH ,the bike is lower with less frontal area than a Guzzi. The Triumph on the dyno makes 55 rear wheel HP and 46 ft lbs of torque...
 You can't compare different dynos and an inertia type "DynoJet", the most commonly used for bikes, will give slightly higher power readings than a "load" dyno like Superflow or Mustang.
 So...I would say my 950 cc Cali 2 made about 50 rear wheel hp, or 55-57 at the flywheel..
 

[donn]

I know the couple times I've cranked my 1985 California II up all the way, it scared the crap out of me!  This is not my lovely touring barge!

[bad Chad]

That seems right. What don't you like about that?

Its just under a 10% loss, thats extremely good for a Guzzi shaft system.  The v7 series is rated at 48Hp, but usually puts down about 40hp to the ground, a substantially higher loss rate percentage wise.

[Moto]

Its a bit of a head scratcher.   The new v9s are claimed to put out 55hp at the crank.  Yet every dyno I have seen puts them at 50-51hp to the ground?  How can that be?

I don't remember this. Can you give a link to such a dymo test result?

Thanks.

[Chuck in Indiana]

To answer the OP's original question.. No. 

[swooshdave]

To answer the OP's original question.. No. 

Yes, I already knew that. Marketing was fast and loose back in those days.

I was just bemused by the vast difference in stated hp between the 850T and 850 LeMans (55 vs 70/80). I obviously need a LeMans...

[bad Chad]

Google will get you what you ask for.

[Huzo]

Its a bit of a head scratcher.   The new v9s are claimed to put out 55hp at the crank.  Yet every dyno I have seen puts them at 50-51hp to the ground?  How can that be?

Wouldn't that be due to the frictional losses through the drive train ? Power is a rate of doing work, force x distance/ time , in the case of a rotating crank it's torque x rpm. If there were no losses in the drive train then the calculation of torque x rpm at the crank would be the same as that at the rear wheel. If you had say 10 Nm x 5,000 rpm at the crank the calculated figure would be 50,000 watts or 50 KW , with no frictional losses that figure at the rear wheel after the gearbox has it's say, could be more like 50Nm x 1000 rpm for a power rating of  again 50,000 watts or 50 KW . That's an idealised example obviously, but the point is that an engine doesn't "put out" power, it's a mathematical expression of a rate of doing work. If a Guzzi Le Mans goes up a one mile hill in one minute a certain amount of work has been done in a given time, an equally weighted Suzuki GSXR 1,000 might do it in 30 seconds, the power figure would be double that of the Guzzi in that case given that the work was done in half the time. FORCE x DISTANCE / TIME

[oldbike54]

 Huzo , go back and reread Chad's post , you aren't understanding his point .

 Dusty

[swooshdave]

Google will get you what you ask for.

Are you sure?

[Ion66]

MY Breva 1200 is rated at 95 hp. I have yet to see a dyno test of that 2 valve head, motor, Breva, Griso or Norge, that makes over 73. Not sure if my Sport makes a touch more or not, but even for a shaft drive bike, that's a pretty hefty drop. Mind you, that's 95 measured at the brochure. Most Japanese manufactures of sporting bikes have moved on from horsepower lies, and now lie about dry weight and rpm's. If my Breva was Japanese, it would weight 450 pounds and rev to 11 grand! :)

[Ion66]

There's only 2 things in this world guaranteed to increase horsepower, without touching the motor, and that's a brochure, and nostalgia.

[canuck750]

There's only 2 things in this world guaranteed to increase horsepower, without touching the motor, and that's a brochure, and nostalgia.

I can offer a third,

get the rider to loose 15 lbs, that should add the equivalent of 5 hp.

My bikes keep loosing hp as the years go by and my waistline swells

[charlie b]

LOL, yep.

I listened a a guy at the Sun morning gathering go on and on about his Duc 1199 and how much money he was spending to save a few ozs here and there which really added up to about 5lb saved in weight.  He was so proud he looked like a new father.  No one bothered to point out to him the 30lb gut he was carrying on the bike.

My brother does long distance bike racing and they have the same type.  Save a few oz by spending several hundred/thousand more on the bike, yet are 20lb overweight.

PS when I had to lose weight a few years ago (30lb) I was shocked at the difference in the feel of the bike.  Gave me more incentive to not gain it all back.

[Gliderjohn]

My losing 35ibs and when I don't need them removing the side bags makes a noticeable difference.
GliderJohn

[Huzo]

Huzo , go back and reread Chad's post , you aren't understanding his point .

 Dusty

Yeah Dusty, with me that's always a distinct possibility, but I thought it was addressing the issue that Chad raised regarding how you can have a claimed figure higher at the crank than what is shown at the rear wheel, but sorry if I'm off topic.

[oldbike54]

Yeah Dusty, with me that's always a distinct possibility, but I thought it was addressing the issue that Chad raised regarding how you can have a claimed figure higher at the crank than what is shown at the rear wheel, but sorry if I'm off topic.

 No worries mate , it was kind of confusing . I think he was referencing the lesser reduction of HP on the V9 as compared to the losses on the V7 .

 Dusty

[Huzo]

Yeah no worries mate. BTW how ya' been ?

[mgmark]

A friend put his 1000 LMIV on the Dyno at the Parry Sound Sport Bike Rally and got 62HP. Heads were done by Manfred along with the usual carb and exhaust mods. His bike would pull my 850 LM also with Manfred Hecht headwork so I assume mine is less.

Pete

I put my '89 LeMans 1000 on the Dynojet dyno at Daytona Bike Week years ago, when the bike was only a couple of years old. K&N filters, rejetted, Dyna ignition, Staintune exhaust. It pulled 67 on their dyno, and it was the roll-on king against any other Guzzi of the time I tried it against. Big Harleys on the same day were pulling low 60s so I guess it compares somewhat accurately.

Mark

[oldbike54]

Yeah no worries mate. BTW how ya' been ?

 Ripper . And you ?

 Dusty

[Kai]

I put my '89 LeMans 1000 on the Dynojet dyno ... It pulled 67 on their dyno.......
Mark

That's good!

Had my LM 1000 on the dyno with new piston rings, overhauled heads, Sachse ignition, Mistral manifold and crossover, Lafranconi Comp,  Scola 3.2 cam,  original air filter housing without filter, properly jetted to finally achive 75 hp at the rear wheel, yahoo  That are roughly 84-85 crankshaft hp, barely a few more than the claimed 82 brochure pony's. This number was imho a pure marketing value to be far enough above the BMW R 100 RS. A "7" as first number did for sure not sound impressive enough, 82 suggested 80 for sure   

Kai

[bad Chad]

Pete has said that about 75hp to the floor is the most your going to get out of a 2v big block, seems reasonable, to me.

The b1100 claimed 86hp, and I think the b1200 was 95hp.  9 more hp, from 80 odd cc?  Seems like a big stretch to me!

[Chuck in Indiana]

Pete has said that about 75hp to the floor is the most your going to get out of a 2v big block, seems reasonable, to me.

The b1100 claimed 86hp, and I think the b1200 was 95hp.  9 more hp, from 80 odd cc?  Seems like a big stretch to me!

<throwing down gauntlet> Ok, that does it. I gotta dollar that sez the Mighty Scura will do more than 75 hp. 

[LowRyter]

I hear that Scura has so much power that it will eat the transmission. 

[pete roper]

<throwing down gauntlet> Ok, that does it. I gotta dollar that sez the Mighty Scura will do more than 75 hp. 

Dunno how much outright power that thing makes but it's midrange torque is just stupid.

For most 2V big blocks in *Normal* trim though mid seventies is where it's at, carbed or FI. Yes, you can extract more, a fair bit more, but it will reduce service life and reliability exponentially.

Pete

[mtiberio]

My 990cc race bike with all the neat-o manfred hot cams and porting dyno'd at 70HP rear wheel, and a boat load of torque. YMMV