Late model pork chop to engine brace

[Greg Field]

Well, hell. You're all right. No one needs a tire wider than a 4.00-18. My Eldo keeps up with V11 Sports just fine on these bicycle tires. Nothing but fashion upgrades ever since . . .

[Guest ratchethack]

Well, hell. You're all right. No one needs a tire wider than a 4.00-18. My Eldo keeps up with V11 Sports just fine on these bicycle tires. Nothing but fashion upgrades ever since . . .

Wot d'you figure Tenni would've given to ride on a 4.00/18 mfg'd. to current sport/touring standards??

 

Omobono Tenni, Isle of Man TT, 1937. On a 500 Guzzi.

[FuelCooler]

FC: I think I have one of those block at work. I'll check on Tuesday. If I do, we can discuss options such as lending it to you or measuring it.

 

Thanks, Greg. Any help is more than apprieciated.

 

Steve

[FuelCooler]

If you're going to the trouble of doing it at all, have you considered more elegant ways to brace the frame/sideplates. I think the Guzzi method is pretty slapdash & ugly. Sportis had a brace between spine & top of gearbox.

 

I have installed the Sporti brace already, and the biggest diffence I can tell (like Ratchet) is a bit more vibration!

The late model Guzzi method isn't very elegant, but they are the ones who counted the beans and did it that way. It cost them $ to put that extra / different part on the bike, I figure there is sound engineering behind it. Some folks might not realize this, but the late model brace triagulates the porkchops together as well as run up to the motor. The early brace does neither.

Cheers

Steve

[FuelCooler]

As an alternative idea, one could fabricate some brackets to run from from the left pork chop to the starter mounting bolts, and from the right porkchop to the case.

And then make some bracket like the one on the Japanese site

 

That stuff looks pretty good dlaing, and I was thing of making something similar, until I got my hands on the Guzzi parts....

Quoting myself from my repliy to Baldini:

"Some folks might not realize this, but the late model brace triagulates the porkchops together as well as run up to the motor. The early brace does neither."

 

Cheers

Steve

[FuelCooler]

Let me put it this way: If you had your suspension setup correctly, had a decent set of tires, and aggressively rode your favorite twisting mountain road (using all the tread to the edges) with your 180 on a 5.5" wheel, then ran it the same way with a properly matched 160/60 on a 4.5" wheel (all other parameters being equal), I reckon you'd arrive at the same conclusion, and there wouldn't be anything close to any doubt about it . . .

 

 

OK, just for some reference: I am older and slower now, but in 1993 WERA sent me an expert license after 5 weekends of racing (including the GNF), I was hoping they would let me race the Seca II Challange, which was novice only. Nope. Didn't even get a full season as a novice!

Plus, I have always been my own tuner. Not that I am a master tuner or rider, but I am no beginner either!

 

Ratchet, I like you.

Answer me one question, yes or no. Just yes or no.

 

Have you ridden a properly set up SHORT FRAME V11 with a 5.5 rim and 180 tire?

 

EDIT: Have I ridden a properly set up SHORT FRAME V11 with a 4.5 rim and 160 tire?

No.

But I have ridden mine with the 160 and the forks dropped 9mm. It handled fine like that if you didn't pitch it around too hard (soft springs).

[Skeeve]

Yes, indeed. The highly sought after, and oh-so-rare "piastra colleg". I've made one up and installed it. IIRC, Docc put one in same time I did, about 4 years back. "Short frame" sports came with the welded-in frame tang to attach it installed -- but with no plate. Does it do anything at all? Without a strain gauge, I reckon it's impossible to tell. Apparently Guzzi didn't think so, or they'd have saved us the trouble.

 

Well, a certain motorcycle design expert (who incidentally hints that Dr. John "lifted" the whole spine frame idea from one of his designs) suggests when modifying old Superbike frames [AHRMA variety now; current "back in the day"] which were notoriously flimsy, he'd mount the frame on the wall, stick a bar through the headstock, give a measured pull & record the deflection. After making the mods, giving another pull & checking deflection, it was readily apparent how much improvement there had or had not been. So you could always try that method, Ratch'!

 

As for Guzzi's thinking on it's importance, something to consider is their financial situation when the part was deleted. A seemingly minor part that from your own admission, is a b!tch & a half to get in place: yes, on the bare frame on the construction line it wouldn't be near as hard, but it still may have (probably) represented a considerable savings of employee time to eliminate a $.20 part which provides a benefit that the vast majority of riders would never notice or lament its passing. So if Guzzi was making 3000 bikes/yr and could eliminate that part it's only $600 saved in parts for the year, but the $3 in employee time to get that mierda lined up w/ frame & engine & get it all torqued down & then have it in the way for later stages of construction, etc. etc.: heck, at the end of the year, that's close to $10k saved!

 

And bean-counters LOVE that kinda sh!t. The factory test riders can piss & moan all they want about how much less planted the bike feels: the accountants are just going to shrug & say "you can keep one on your bike if you like it so much... but the rest of the bikes out the door live without!"

 

On a related note: how hard would it be to set up a couple of small cables w/ turnbuckles from clutch bell to spine? Steel is much stronger in tension than compression, and drilling/tapping a couple holes in the spine for mounting could be down w/ engine in place. By "anchoring" the midpoint of the spine in this fashion, it would use the mass of the engine to damp out any torsion f/x on the headstock while leaving the sideways deflection of the frame relatively unchanged [which is what the racing people had to start dialing back in after getting everything too rigid a few years back, and realizing that some of the "suspension" used when leaned way over was in fact frame flex...]

 

Just some random thoughts. Don't mind me, I've just been wasting my time playing around with updating an old Mac p'book for most of the day. Horribly slow & creaky, but I do love the old "classic" MacOS. It sure does some funny things to my thought processes tho'...

 

[dlaing]

Yes, indeed. The highly sought after, and oh-so-rare "piastra colleg". I've made one up and installed it. IIRC, Docc put one in same time I did, about 4 years back. "Short frame" sports came with the welded-in frame tang to attach it installed -- but with no plate. Does it do anything at all? Without a strain gauge, I reckon it's impossible to tell. Apparently Guzzi didn't think so, or they'd have saved us the trouble.

There were a few V11s that cracked at the mount point near the Piastra Colleg placement point.

I would find it hard to believe those same Guzzis would have cracked at that point if the Piastra Colleg had been in place.

My common sense replaces strain gauges and slide rules

But then again if it transmits more vibration, who knows? Maybe it would crack more easily, but I doubt it.

[Baldini]

I have installed the Sporti brace already, and the biggest diffence I can tell (like Ratchet) is a bit more vibration!

The late model Guzzi method isn't very elegant, but they are the ones who counted the beans and did it that way. It cost them $ to put that extra / different part on the bike, I figure there is sound engineering behind it. Some folks might not realize this, but the late model brace triagulates the porkchops together as well as run up to the motor. The early brace does neither.

Cheers

Steve

 

I wasn't suggesting gbox brace as an alternative fix, just as a related item. Guzzi bracing looks a bit of a lash up, & if you're going to the trouble of pulling it all apart there may be a more elegant solution that you might employ as you have the skills but don't have economies of scale etc to consider. Although it braces the sideplates, & will help, I don't think the bracing contributes that much to firming up the steering head relative to the crosspiece at the bottom of the spine, which is where I suspect some of the problem is. My Scura, which has the bracing feels pretty flexible pushed hard (I've not ridden early V11 or Sporti so can't compare, but Scura is nowhere near as solid as Tonti). Skimpy swingarm probably doesn't help either. Good luck with the job anyhow!

 

KB

[Baldini]

Well, hell. You're all right. No one needs a tire wider than a 4.00-18. My Eldo keeps up with V11 Sports just fine on these bicycle tires. Nothing but fashion upgrades ever since . . .

 

Horses for courses. This 110 was amongst lots of big fat tyres on track the other day. Didn't want for grip. Cornering grip does not depend on width but on tyre type, you only need the width for applying big power (& I suppose braking from big speeds?), which we don't have.

 

KB

[motoguzznix]

I have installed the Sporti brace already, and the biggest diffence I can tell (like Ratchet) is a bit more vibration!

The late model Guzzi method isn't very elegant, but they are the ones who counted the beans and did it that way. It cost them $ to put that extra / different part on the bike, I figure there is sound engineering behind it. Some folks might not realize this, but the late model brace triagulates the porkchops together as well as run up to the motor. The early brace does neither.

Cheers

Steve

Steve

 

Me too - I like the handling of the old short frame KRs.

 

I installed that triangular bracket too and could not find any difference in driving behavior.

I also installed the front bracket from the newer model- no difference either.

I would also like to install the lower bracket with the lower rails to the engine - but welding on the engine block in that area could be some risk as this is the area of the rear crank bearing. If there comes up a good idea on that subject, I am the first to upgrade my frame.

[dlaing]

For some reason I don't think that 110 tire can keep up with what the GP stars are doing.

Try to find a picture of Mike Hailwood getting anywhere near close to this lean angle of Valentino Rossi.

http://www.raptorsandrockets.com/images/Ro...gello06_03r.JPG

There are other reason to select a wide wheel and tire than just power.

Grip, image, Longevity, comfort, feel, hydroplaning resistance, resistance to steel deck bridge weave, weight, and other characteristics all come in to play.

IMHO a bigger tire has greater longevity, better geometry for resisting touching parts, better grip, better with a heavy load, better comfort, and seemingly better resistance to rain groove weave.

A smaller tire can have nearly as good grip when cornering, better hydroplaning resistance, less weight, better fuel mileage if gearing is out of equation, and better feel.

Go ahead and disagree.

I am certainly open to learn.

[FuelCooler]

Steve

 

Me too - I like the handling of the old short frame KRs.

 

I installed that triangular bracket too and could not find any difference in driving behavior.

I also installed the front bracket from the newer model- no difference either.

I would also like to install the lower bracket with the lower rails to the engine - but welding on the engine block in that area could be some risk as this is the area of the rear crank bearing. If there comes up a good idea on that subject, I am the first to upgrade my frame.

 

Hi Motoguzznix,

I did not realize the front motor bracket was different on the late models. I might have to get that one too.

For clarity - the 'lower bracket with the rails' is the one I am refering to when I mention the triagulation of the porkchops, not the triangular shaped bracket that connects the bellhousing to the frame.

I don't believe there is any welding required to add the lower brace. I appears to be machined (after painting) to allow bolts to thread into the thick area of the casting where (internally) the crank case ends and the bellhousing begins. I could be wrong. That's why I would like to get my hands on some late model cases for measuring and comparing.

I promise to post photos as soon as the work begins.

 

Cheers,

Steve

[BRENTTODD]

hey how did this trun into tire thread. Wait till you guys see my new avon 320 rear tire on my west coast chopper 22 inc rim it really hot

[FuelCooler]

hey how did this trun into tire thread. Wait till you guys see my new avon 320 rear tire on my west coast chopper 22 inc rim it really hot

 

Sweet, your bike needed more chrome!