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General Category => General Discussion => Topic started by: Moto on February 27, 2016, 03:03:54 PM

Title: Table of flywheel weights for Guzzi big twins -- REVISED
Post by: Moto on February 27, 2016, 03:03:54 PM
Dear all,

I just created a table of flywheel weights for most of the big twins (excepting the 8V models in particular).

This is a topic that often comes up, and I have not found a similar reference before. Let me know of corrections (and your sources for them).

Some of the weights from Stein-Dinse might be shipping weights. It's just hard to be certain. If so, they would be about 0.3 kg more than the actual flywheel weights.

As you peruse the table, remember that the inertia of a flywheel also depends on its distribution of mass, so the weights themselves are just suggestive of the effects of the different flywheels.

Enjoy!

Moto

(http://i127.photobucket.com/albums/p135/motocomo/Guzzi%20flywheel%20weights_1.png) (http://s127.photobucket.com/user/motocomo/media/Guzzi%20flywheel%20weights_1.png.html)

[EDIT -- SEE REVISED VERSION BELOW FOR COMPLETE ASSEMBLY WEIGHTS.]

Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Antietam Classic Cycle on February 27, 2016, 03:22:40 PM
What, no Convert flywheel weights?  :wink: I can get those for you if you'd like. Good job!
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: oldbike54 on February 27, 2016, 03:52:12 PM
 Interesting  :thumb:

 Dusty
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 28, 2016, 06:17:27 PM
What, no Convert flywheel weights?  :wink: I can get those for you if you'd like. Good job!

Happy to put them in if you've got em! Do the Convertocenti swap them for "improved" performance?

Also, does anyone know the weight of the flywheel on the 8V Griso? And is that the same exact flywheel for all the 8V's?

M.

Title: Re: Table of flywheel weights for Guzzi big twins
Post by: John A on February 28, 2016, 07:34:19 PM
Has anybody made the flywheel heavier ? I'm thinking that might be good for a sidecar rig. Inertia rings I think they are called. I expect that's just a fancy term for a machined chunk of steel bolted to the flywheel.
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Antietam Classic Cycle on February 28, 2016, 08:20:04 PM
Has anybody made the flywheel heavier ? I'm thinking that might be good for a sidecar rig. Inertia rings I think they are called. I expect that's just a fancy term for a machined chunk of steel bolted to the flywheel.

The V7/Ambassador/Eldorado flywheel pretty much uses all of the available space in the "bellhousing". At 13 lbs. for just the flywheel (without plates, springs and cover plate/ring gear) it's plenty heavy for sidecar duty.  :wink:
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: kfz on February 29, 2016, 03:28:29 AM
Assume this is just the flywheel and not the ring gear or anything else.  Which I guess is a constant anyway.


Kev
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: pauldaytona on February 29, 2016, 03:43:47 AM
I have an 8V clutch , weigh it tonight.
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: pete mcgee on February 29, 2016, 04:04:54 AM
Indisputable proof that cabin fever is alive and well in the northern hemisphere.
Your hard work is appreciated and it will be useful for someone, somewhere.
Nice one.
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: John A on February 29, 2016, 07:15:12 AM
The V7/Ambassador/Eldorado flywheel pretty much uses all of the available space in the "bellhousing". At 13 lbs. for just the flywheel (without plates, springs and cover plate/ring gear) it's plenty heavy for sidecar duty.  :wink:
I've been useing a ten spring, the eight springs slip for me on a hard pull unless they are almost new. I spose I could detune( yeah like I'm gonna do that!) maybe I could machine the pockets in a Ambo clutch for some springs, years ago I searched for some stronger springs, other than Barnette, no luck. Which led me to the inertia ring option but like you pointed out, I will run out of room fairly quickly.
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Antietam Classic Cycle on February 29, 2016, 09:38:50 AM
Assume this is just the flywheel and not the ring gear or anything else.  Which I guess is a constant anyway.


Kev

The V7/Ambassador/Eldorado ring gear is heavier as well.
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Roach Carver on February 29, 2016, 09:50:26 AM
Sorry for the noob question... Are these all interchangeable?
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 29, 2016, 11:13:02 AM
Sorry for the noob question... Are these all interchangeable?

Mostly, depending on the work you're willing to do. They differ in the presence or absence of electronic timing triggers or (nonelectronic) marks for various applications. They also take either 8- or 10-spring clutch assemblies, but those can be substituted as necessary. There may be other problems that come up in certain cases that I'm not aware of. Swaps among the pre-electronic bikes are pretty straightforward.

Guzziology is the best place to see the details.

I'm reluctant to simply copy all additional information into my table from Guzziology, since that book should be purchased by anyone contemplating flywheel changes. It's money you won't regret spending: 770 or so pages in the latest edition. Get it brand new and up to date for $65 directly from motointerntional.co m. (Avoid resellers looking for a quick buck on Amazon.)

Moto

Cabin fever is the right diagnosis, Pete McGee!
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Roach Carver on February 29, 2016, 11:49:17 AM
I have my guzzioligy book already. Used it for my last cylinder replacement . Thanks for the help!
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 29, 2016, 12:02:09 PM
The V7/Ambassador/Eldorado ring gear is heavier as well.
Charlie,

I have read before that the first bikes had heavier ring gears, but don't know the exact history.

MG Cycle lists part number 17067900 as suitable for all the M8 screw models, including the Ambo and Eldo right through the Vintage, and says it weighs ~4.6 lbs. (2.09kg).

They also list a substitute number 12067900 for all the same models. They say this one weighs 4.73 pounds (2.15kg).

Am I right in thinking 12067900 is really the Ambo/Eldo item and 17067900 the one for the later bikes? What about the V7 Sport of 1974 and the T?

Do you have better weight figures than MG Cycle's? If so, I'll add it to the table.

Moto

P.S. The ring gear (strangely listed as a "chain ring") for the V11, the Griso and all the 2V Carcs is 01067930. Stein-Dinse lists its weight at 1.6kg (it could be a shipping weight). Any other info?

Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 29, 2016, 12:07:09 PM
I have my guzzioligy book already. Used it for my last cylinder replacement . Thanks for the help!

You're welcome! Anyone who owns Guzziology and has replaced a cylinder is a most honorable Guzzista.

Moto
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Antietam Classic Cycle on February 29, 2016, 12:10:31 PM
Charlie,

I have read before that the first bikes had heavier ring gears, but don't know the exact history.

MG Cycle lists part number 17067900 as suitable for all the M8 screw models, including the Ambo and Eldo right through the Vintage, and says it weighs ~4.6 lbs. (2.09kg).

They also list a substitute number 12067900 for all the same models. They say this one weighs 4.73 pounds (2.15kg).

Am I right in thinking 12067900 is really the Ambo/Eldo item and 17067900 the one for the later bikes? What about the V7 Sport of 1974 and the T?

Do you have better weight figures than MG Cycle's? If so, I'll add it to the table.

Moto

P.S. The ring gear (strangely listed as a "chain ring") for the V11, the Griso and all the 2V Carcs is 01067930. Stein-Dinse lists its weight at 1.6kg (it could be a shipping weight). Any other info?

That aftermarket 12067900 is quite a bit different than an original, looks like some material has been machine away on the outer side and the holes are larger. I'll weigh the Convert flywheels and some o.e. ring gears later today.
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Groover on February 29, 2016, 01:25:33 PM
Nice chart. Thanks for making it! Do all the flywheels in that chart interchange?

Title: Re: Table of flywheel weights for Guzzi big twins
Post by: JeffOlson on February 29, 2016, 02:05:01 PM
I like the idea of a heavy flywheel for the relatively relaxed riding that I do. Any guesses as to the weight of my 8V Norge's flywheel?
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 29, 2016, 03:28:39 PM
That aftermarket 12067900 is quite a bit different than an original, looks like some material has been machine away on the outer side and the holes are larger. I'll weigh the Convert flywheels and some o.e. ring gears later today.

Charlie,

I just checked Greg Bender's copy of the V700 parts list. The correct number for the ring gear is indeed 12067900. So if the ones you have turn out to weigh more than MG Cycle claims for theirs, that would be very interesting.

The same number is listed in parts catalogs for the Ambo, Eldo, 850 GT and V7 Sport (1973).

The 750-S and 850-T, however, list the lighter 17067900 used by the T3 and the vast number of later Tontis. The S3 parts catalog just lists differences from the T3, and since it doesn't show a different ring gear the S3 must also have used the 17067900.

So the transition to the lighter ring gear was roughly between the V7 Sport and the 850-T.

Moto
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: pauldaytona on February 29, 2016, 04:37:12 PM
The 8v clutch is build completely different, so flywheel is irrelevant.  Complete it is 6.3kg, the starter ring alone is 538 grams from that.

(http://s8.postimg.org/bdu3v78w5/2016_02_29_23_31_02_Medium.jpg)
(http://s8.postimg.org/5bmh4pkg5/2016_02_29_23_31_58_Medium.jpg)
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 29, 2016, 04:58:54 PM
The 8v clutch is build completely different, so flywheel is irrelevant.  Complete it is 6.3kg, the starter ring alone is 538 grams from that.

Perfect! I'll modify the table.

If anyone could provide a total weight for the components of the dual-plate (pre-8V) clutch assembly besides the flywheel and ring gear, I could improve the table further.

This would be: the friction and driven plates, the pressure plate, the springs. (All weighed together, not separately.) Am I forgetting something? Those components are pretty constant across the various applications, aside from minor differences due to types friction plates, etc.

Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Antietam Classic Cycle on February 29, 2016, 06:10:33 PM
Okay, here's what I got, all weighed on my electronic postage scale, rounded to the nearest tenth.

Convert:
- early stamped "flywheel", w/o ring gear: 3 lbs., 3 oz.
-   "          "             "       , with ring gear: 4 lbs., 12 oz.
- late machined flywheel (with integral ring gear): 11 lbs., 8 oz.
- torque converter (drained): 7 lbs., 15 oz.

California II:
- flywheel: 9 lbs., 5 oz.
- ring gear: 4 lbs., 14 oz.

Clutch plates:
- friction plates:
  - slotted/spoked, pair: 1 lb., 8 oz.
  - solid, pair: 1 lb., 12 oz.
- intermediate plate: 9.5 oz.
- pressure plate: 1 lb., 15 oz.

Clutch springs (8): 3.2 oz.

V7, Ambo/Eldo original flywheel: 12 lbs., 15 oz.
V7, Ambo, Eldo original cover plate/ring gear (1206 7900): 5 lbs., 3 oz.
                   
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 29, 2016, 11:14:44 PM
(http://i127.photobucket.com/albums/p135/motocomo/Guzzi%20flywheel%20weights_3.png) (http://s127.photobucket.com/user/motocomo/media/Guzzi%20flywheel%20weights_3.png.html)

Notes on the revised table:

I. The ring gears.

There are two versions for the pre-CARC big twins:

Version 1 (1206 7900):

   Charlie reports (1206 7900): 5 lbs., 3 oz., or 5.25 lbs., or 2.38kg.

   Stein-Dinse lists a �starter ring big models, original form� 17067900, weighing 2.33kg,
which is 5.14 pounds, close to Charlie�s 5.25 lbs.

   MG Cycle lists 12067900 at 4.73 pounds (2.15kg), but Charlie says this version looks cut down.

   Original parts lists show ring gear 12067900 for the V700, V7 Special, Eldo, Ambo, 850 GT and V7 Sport (1973). (The 850-T, 750-S and 750-S3 had the later version, below.)

   Verdict: The correct number is 12067900 (Stein-dinse has it wrong), and I take the weight to be 5.25 lbs. for the original version, per Charlie�s measurement today.

Version 2 (1706 7900):

   Charlie reports a California II ring gear at 4 lbs., 14 oz., or 4.88 lbs., or 2.21kg.

   Stein-Dinse lists a second flywheel under the same number, 17067900, at 2kg.

   MG Cycle lists 17067900 at �~4.6 lbs.,� or 2.09 kg.

   Verdict: The proper number is 17067900, and Charlie�s weight of 4.88 lbs. or 2.2kg, since it was taken today for this table, is taken as accurate.

II. Weight of usual big twin clutch plates, springs:

   Charlie�s inventory [w/ oz. conversions]:

     Clutch plates:
     - friction plates:
       - slotted/spoked, pair: 1 lb., 8 oz. [24 oz.]
       - solid, pair: 1 lb., 12 oz.         [28 oz.]
       - intermediate plate: 9.5 oz.        [9.5 oz]
       - pressure plate: 1 lb., 15 oz.      [31 oz.]

     Clutch springs (8): 3.2 oz.            [3.2 oz]

     Total = 95.7 oz., or 5.98 lbs., or 6 lbs. rounded.

   Kirby1923 reported:

      With all components stacked..

      Two clutch plates (SD-TEC)
      One intermediate plate
      All 8 springs
      Pressure plate
      4.1 lbs

   Kirby used a bathroom scale, while Charlie used a postage scale. I judge the postage scale to be presumably more accurate in this range (especially since its results get checked by the post office when a package is mailed). So I again use Charlie�s figure.

The new �COMP. ASSY.� column shows an estimated complete weight of the clutch assembly, calculated by adding flywheel + ring gear + 6 lbs. But the complete weight of the 8V assembly, which doesn't have a separate flywheel, is Paul's direct measurement.
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: Moto on February 29, 2016, 11:22:04 PM
I like the idea of a heavy flywheel for the relatively relaxed riding that I do. Any guesses as to the weight of my 8V Norge's flywheel?

See the 8V line in the revised table.

Update: Checking some 8V parts diagrams I now see that there are different part numbers for the California 1400, Griso 1200, and Norge 1200, though the pictures look the same. I don't know if the weights differ, and I'm not sure which 8V clutch Paul weighed.
Title: Re: Table of flywheel weights for Guzzi big twins -- REVISED
Post by: Antietam Classic Cycle on March 01, 2016, 07:16:42 PM
 :thumb: :thumb:
Title: Re: Table of flywheel weights for Guzzi big twins -- REVISED
Post by: Matt on March 20, 2016, 04:16:17 PM
I have a flywheel from my old Quota and the flywheel I just pulled out of a T-3 on the bench. T-3 is 9.4lb and the 1100ES Quota is exactly three lb lighter on my certified  :wink: bathroom scale. Call it 6.4lb. I can't imagine Guzzi would make a special run just for the Quota but I don't see any like it on the chart.

I put a T-3 flywheel in my Quota for more mass, made it a better bike for my purposes and 5th gear was actually usable on the highway. 

Matt
Title: Re: Table of flywheel weights for Guzzi big twins
Post by: pauldaytona on March 20, 2016, 06:32:13 PM
See the 8V line in the revised table.

Update: Checking some 8V parts diagrams I now see that there are different part numbers for the California 1400, Griso 1200, and Norge 1200, though the pictures look the same. I don't know if the weights differ, and I'm not sure which 8V clutch Paul weighed.

 That is a  stelvio 2012 one. The weight of the 8v clutches is all the same.