In search of taller gearing for v-11 sport

[Guest jamesmachine]

Im the owner of a 2004 V-11 Sport and I really enjoy the bike, however if I had a complaint about the bike it would be that the final drive ratio is to low. When cruising down the hiway at say 110 MPH with a steady throttle the tach hanging at 6500 RPM, I find the RPMs to be to high for my liking. I feel as if the engine is screaming and working harder than it has to. The V-11 sports engine makes big torqe and should easily be able to pull a higher gear ratio without loosing to much acceleratin in the process while yeilding a significantly higher top speed. In my opinion the V-11 sport can easily redline its sixth gear while yeilding only about 137 MPH acording to published specifications. The bike is low gear ratio limited and can benefit greatly with higher gearing, which begs the question, is there a higher gear ratio avalible for the rear bevel drive? The rear bevel drive housing apears to be exclusive to the V-11 sport chassis and I've visually noticed that the same rear bevel drive housing is employed by the MGS01. I was under the impression that V-11 sports are raced in Europe, if this were the case one might think that opional rear drive ratios would have to be avalible so as to tailor the race bikes to the various tracks. Opional gear ratios wanted here.

[pete roper]

Alas, unless there is some aftermarket specialist in europe, (and I don't know of one.) who is putting alternative crownwheels and pinions into production I'm afraid the answer is no. The situation is further complicated by the V11 bevel set being unique in that a.) the crownwheel is machined along with the splined hub as a single part as opposed to the earlier bikes which have the crownwheel bolted to the hub and b,) the V11 pinion has an outrigger bearing at the end of the shaft for additional support meaning that even if you could cobble something together, (Unlikely.) using and earlier CW&P it still wouldn't work right. There is also the issue of pinion splines and the ratios themselves. I can't offhand remember what the ratio or tooth count is on the V11's??????

 

Pete

[Paul Minnaert]

If you really, really want it, you can exchange the primary ratio in the gearbox for the one from the mgs01, that's taller. 20-31 for the mgs01, 19-32 for the v11, so in numbers now you have 113 mph at 6500 then you have that at 6000.

[Skeeve]

If you really, really want it, you can exchange the primary ratio in the gearbox for the one from the mgs01, that's taller. 20-31 for the mgs01,  19-32 for the v11,  so in numbers now you have 113 mph at 6500 then you have that at 6000.

59407[/snapback]

 

Thanks Paul, that's good information! So the final drive ratio on the MGS is 1.55:1, the V11s are 1.68 (roughly, lots of less significant digits there.) Notice that in both cases, there's an odd # of teeth on one gear; that's important. Other combinations (assuming the mmpbflmpblplg [yes, I can't remember the technical term for fitting up gear radius' vs. their teeth shape, whatever it is] is compatible) would be 20/32 & 19/31. These work out to 1.60 & 1.63, except you never want two even-toothed gears to be working on each other, since they wear into each other because the same teeth are always in contact & then when they get taken apart & put back together, suddenly they don't work right anymore...

 

So of the options, it would be the 1.68 of the original V11 final drive, the 1.55 of the MGS, & hypothetically, a 1.63 ratio of the combination of the V11 shaft & MGS crown wheel. This last would give a (theoretical) top speed of 141mph vs. the 137mph claimed; the 1.55 MGS drive ratio would yield a 148.5mph top end [again, highly theoretical!]

 

Seems like a lot of work & expense for 11.5 measly mph on top, but then again, being able to cruise at even a few rpm less can make ALL the difference, comfort wise.

 

Ride on!

[droydx]

For gods sake, don't believe a Guzzi speedo!

 

110 fo extended time on a V11 sport! You go, right on!

 

Droyd

[O2 V11]

jamesmachine, does your bike consistently run to redline in 6th? If it does what mods have you done to it and what model is it? I would like very much for mine to be able to do this. I feel lowering the final drive ratio would not give a higher top speed if it can't redline in top already.

Rob

[richard100t]

This is a good thread for me because I was wondering just the opposite. I was interested in lowering the gears for more power 0-100. Since I have 2 rear drive units I can swap them out depending on what type of riding I want to do. Unfortunately we v11 guys are rare birds so if we want something like that it appears as though we'll have to make it ourselves. Theres 2 gear shops here where I live, sooner or later I'm going to have the pinion gear made for the original rear drive that I broke. When I do I'm going to inquire about having a lower ratio pinion & gear made for the rear drive. The pinion should only cost about $80 but I dont know what the gear would be to have made yet. I will certainly update you guys on that when I do get around to having the work done. Does anyone have a really good idea for a superpower "wheelie" fun gear ratio for the v11?

[pete roper]

Hmmm, sorry, but you can't just have a pinion made. Crownwheels and pinnions have to be lapped together and you certainly can't have one made with fewer or more teeth than standard because even if you could get the toothform to match the different number of teeth would require the axis of te pinion to be moved appreciably closer or further away from the crownwheel. If you were to do that you'd need to reposition the drive box in relation to the rear wheel or run the wrear wheel with an offset to the centreline of the bike.

 

pete

[Paul Minnaert]

Ok for the wheelieking we have something else: the reardrive from the convert:

 

Final 9/34 = 3,7778 now you need 8500 rpm for 113mph in 6. The splines from the convert reardrive are small, maybe Pete can try once if it realy fits, the number of splines is the same. then to fit the convert reardrive, a spacer from 20mm on the right is needed. And a construction to hold the reaction rod. The housing from daytona rs/centauro is the easy way.

[Skeeve]

Ok for the wheelieking we have something else: the reardrive from the convert:

 

Final 9/34 = 3,7778 now you need 8500 rpm for 113mph in 6. The splines from the convert reardrive are small, maybe Pete can try once if it realy fits, the number of splines is the same. then to fit the convert reardrive, a spacer from 20mm on the right is needed. And a construction to hold the reaction rod. The housing from daytona rs/centauro is the easy way.

 

Isn't that the reverse of what he was looking for? The lower the final drive ratio, the taller the gearing, right? So the 9/34 gear pair is significantly taller than the usual 7/33? 8/35? 6/32?(sidecar) pairs. [Question marks added 'cause I'm not certain about the correct #s for any of the Guzzi final drive ratios offered over the years, but seem to remember numbers vaguely like these being mentioned here & elsewhere.]

 

None of which has any relevance, of course, given the huge departure from tradition that the v11 6-speed encompassed. But just came across this thread again after so long & thought that some clarification was called for.

[Dan M]

None of which has any relevance, of course, given the huge departure from tradition that the v11 6-speed encompassed. But just came across this thread again after so long & thought that some clarification was called for.

 

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

[rocker59]

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'd rather have a bike that pulls redline at 135/140mph and enjoy the better accelleration at legal speeds than to have a bike that's geared to the moon and can't pull top gear.

 

The Triumph Sprint I had was geared for something like 180mph from the factory. Of course there was no way it would pull all that gear. 7,000 rpm in top gear with a redline of 9,500rpm. In fact is was a dog in 5th and 6th gears because of the tall gearing. When it was time for a chain and sprockets, I ordered an OEM set for a Tiger from Triumph. What an improvement! Now it would pull redline at about 145mph and had great accelleration all the way there!

 

One of the first things I noticed about my Nero Corsa was the great gearing as compared to my Sport 1100.

 

Personally, I wouldn't change a thing.

[Ryland3210]

I liked the gearing on my 6 Speed Z28. 5th was designed for max speed at peak HP, while 6th was an overdrive. Five gears for racing was plenty for me, and 6th yielded 23.5 MPG on average, in spite of 5.7 liters producing 315 HP with a conservative compression ratio I could feed with regular gas.

 

Here's my I'd love it if my '04 sport had the same arrangement. Can't be too difficult to change the 6th gearset. Wouldn't that be a lot easier than changing the crown and pinion? And that would retain the 1st to 5th ratios.

[Guest ratchethack]

I've always been very pleased with the ratios on the 6-speeder. Though that gorgeous torque spread certainly doesn't NEED all those ratios, it sure is nice to have 'em -- nicely spaced, too:

 

1st = 1:2.4

2nd = 1:1.7778

3rd = 1:1.3636

4th = 1:1.1111

5th = 1:0.9655

6th = 1:0.8519

 

Yep. Both 5th and 6th are overdrives thru the box.

 

Overall (engine to wheeel) thru the bevel drive in 6th = 1:4.1737

 

SOURCE: Service Manual, Moto Guzzi S.p.A. Tech Pub Cod. 01 92 01 31

 

Not that I don't take the Guzzi out and let 'er "breathe" now 'n then , but unless you're racing, why f'er the luvva Mike would ye be messin' with that??!! unless you ride the Autobahn -- or here in the USA, if you frequently consider y'erself exempt from the law by +(40-70) mph North o' the max posted limit?!

 

Saw a guy on the 11 o'clock news awhile back doin' semi-spectacular "on location" heli-cam footage on the I-5 (in traffic) for his upcoming trial. . . looked a coupla times like he could've used another cog -- or maybe even 2. D'ya reckon it'd have made a better news clip if he'd had 'em?!

[Ryland3210]

I like having a real tall top gear just for long distance slab cruising. I typically do 73 when the limit is 65, and higher when the limit is higher, or when I'm buzzing along with lots of others doing the same thing. E.g. on the New Jersey Parkway, the posted speed limit is 55. The average speed in the two fast lanes is 75, even when traffic is heavy. Under those conditions, going with the flow is the safe way to drive and saves time, too.

 

Seems to me the 1100 is up to the task of a taller top gear for cruising purposes.

 

Unfortunately, in taking a look at the service manual, near as I can tell, the driven 6th gear is already about as small as it can be. Thought I had a neat project to work on, now that my warantee is about over. I'm sure something else will come along.