Loose rear end?

And a 750 twin is not 100lb lighter than a 180 triple, maybe 20lb max.
 
Thanks guys, I will check the choke cables, the choke plungers are new but I may have insufficient slack in the cables.

NGK BP9ES plugs are the correct plugs to use?

I got the bike through its provincial inspection yesterday with no faults (relief), and now am fully road legal.

Too bad its raining this weekend, but I am off for a weeks riding bringing my RT1150 from Phoenix to home through California, Oregon, Idaho and Montana before I cross the border into Alberta. Looking forward to open mountain roads for a week.
 
Grant said:
And a 750 twin is not 100lb lighter than a 180 triple, maybe 20lb max.
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They're near enough to the same weight. Although some of the triples are actually lighter than the 750 twins.

For example:
SF2/SF3 = 218 kg dry weight
3C = 214 kg

RGS tips the scales at a porky 244 kg
 
NGK BP9ES
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Good plug for the SF and pay no attention to the 3 Cly Mongers.

They're near enough to the same weight. Although some of the triples are actually lighter than the 750 twins.
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Dellortoman: I challenge you to weigh my 2 Cly against your 3 Cyl including a 3/4 fairing and excuse me if I don't take the rear rack off unless you want me to take the fairing off as well.

When I said 100lbs lighter - Depends how you build a Breganzie.

Bet I'm 30 to 60Lbs lighter with the same revs: Don't you 3 Cyls Guys underestimate the Breganzie 2 Cly ;o)

Sorry Clem but SF1's came with Dellorto open mouth VHB30 A's in Canada. Would not mind a set 36's so I could Filter Air. The VHB 30A is a racing Carb and spits at idle - Very dirty Carb with performance.
 
Laverda SF said:
Sorry Clem but SF1's came with Dellorto open mouth VHB30 A's in Canada. Would not mind a set 36's so I could Filter Air. The VHB 30A is a racing Carb and spits at idle - Very dirty Carb with performance.
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The VHB was Dellortos first effort at a large "concentric" type carb.  It was introduced to replace the old types with side float chambers, mainly because these are rather fickle in regard to lean angles.  The VHB was used on just about all types of road machines, EXCEPT racers... italian race/sports bikes were usually still fitted with Dellorto SSI carbs, until the PHF/PHB arrived on the scene.

If your VHBs spit at idle, they're not set up correctly. ::)

piet
 
I do that large sprocket carrier nut up not too tight, that way, it doesn't need loosening for chain tension.
Mixture screws are 1 1/2 turns out if you have an air filter.

Paul
 
sfcpiet said:
The VHB was Dellortos first effort at a large "concentric" type carb.  It was introduced to replace the old types with side float chambers, mainly because these are rather fickle in regard to lean angles.  The VHB was used on just about all types of road machines, EXCEPT racers... italian race/sports bikes were usually still fitted with Dellorto SSI carbs, until the PHF/PHB arrived on the scene.

If your VHBs spit at idle, they're not set up correctly. ::)

piet
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VHB 29's were stock on Moto Guzzi V750 and V850 (Ambassador and Eldorado) Guzzi switched to VHB 30's on the V7 Sport, 750S, 750S3, T and T3 and some of the SP 1000's. Nothing special about a VHB, definitely not a 'racing' carb, they have a simple accelerator pump.



The little brass component at the end of the spring unscrews in half and a tiny plastic ball sits inside. the ball is a valve that lets a sprits of gas into the mixture, the springs often have rusted through and the little brass carrier is plugged solid. I replace the springs on all rebuilds.





VHB's are flat slide and the cap to body joint is prone to warping causing air leaks. I have smeared a tiny bead of clear silicone around the cap to body joint to stop annoying air leaks. I am planning on having a run of Viton cap gaskets made up for the VHB carbs to solve the air leak that the paper gasket will not seal.

Guzzi used the PHF 36 on the 76 and onwards Le Mans 850.

My 73 SF1 came stock with the PHF 36 carbs.

 
Canuck750 said:
VHB 29's were stock on Moto Guzzi V750 and V850 (Ambassador and Eldorado) Guzzi switched to VHB 30's on the V7 Sport, 750S, 750S3, T and T3 and some of the SP 1000's. Nothing special about a VHB, definitely not a 'racing' carb, they have a simple accelerator pump.


VHB's are flat slide and the cap to body joint is prone to warping causing air leaks. I have smeared a tiny bead of clear silicone around the cap to body joint to stop annoying air leaks. I am planning on having a run of Viton cap gaskets made up for the VHB carbs to solve the air leak that the paper gasket will not seal.
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Laverda versions of the VHB do not have the pumps.  In fact, the pumps open a whole new can of worms when fitted to a Lav.  Almost drove me mad trying to set up a set of Guzzi VHBs to my GTL, finally reverted to stock Laverda spec VHB 30s.

Never had any issues with air leaks at the cap, reckon any air finding its way in there would be negligible, unless of course the slide is excessively worn.  Found quite a few cracked carb bodies though... usually from one of the slots under the clamp to the mixing chamber.

piet
 
Thank you Guys in defense of my take on Open Mouth VHB30's. Yes not tuned correctly will spit at idle but do fog and no matter how you jet them will never accept an Air Filter.

Because the VHB 30 is Open Mouth - Stay off gravel roads not saying they will not eat bugs.
 
All Laverda 750 GT and American Eagles, as well as the GTLs, were equipped with exactly the same VHB carbs and came with a very efficient air filter as standard... ::)

Much the same at Moto Guzzi, Moto Morini, Gilera, Benelli, etc, etc.  I think only MV Agusta totally ignored the benefits of an air cleaner.

piet
 
I foolishly removed the air filter from my SF1, kept the airbox. After riding for 2 years, including 800+km of dirt and bulldust from Darwin to Perth (before they sealed it all) my bores were totally shot, top rings in pieces, power down about 50% - rebore went straight to 2nd OS.

Never ridden again without airfilters on a road-going bike. If you use big top quality filters, there is no performance loss, so why throw away all those potential km??!!
 
My SFC obviously ran without filters.

When we opened it this winter, bores and rings were fine after extensive road and track use in the  years I've owned it.
Still on 80  mm pistons which will be going right back in.

Paul
 
Wilfred just did 2 months touring Oz on a twin without air filters, I was shocked to see that. Be interested in his opinion after some Bull Dust track trips. Fesh Fesh to the Africans.
 
Vince said:
Wilfred just did 2 months touring Oz on a twin without air filters, I was shocked to see that. Be interested in his opinion after some Bull Dust track trips. Fesh Fesh to the Africans.
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Vince,

Wilfried already reported the bike was blowing out the breather, but I don't think the Oz trip is to blame.  The bike was pressed into service after a longer hibernation, reckon it will be the rust-ring-in-the-bores syndrome to blame... will see when it gets back.

My 3C hasn't seen an air filter since 1980.  Last set of bores was still very servicable after 60000km, just the pistons were shagged (top grooves worn).  I use an empty air box, seems to keep out the gravel well enough.

piet
 
I just put some pod filters on my track bike. It was a weekend of riding it at Broadford convinced me to do it. The actual track is OK, but the access road from our campsite (we didn't stump up the cash for a pit garage) was a dusty gravel road. There was a lot of traffic on that road so there was dust in the air all day. They'd water it down a couple of times a day, but that just turned the dust into mud for about an hour until it dried out again. At the end of the weekend the entire bike was covered in a layer of dust. Some of it must have got sucked into the engine. The thought of that abrasive stuff getting into my nice new Redax engine made me wince.
 
Dellortoman: My advice is to stay off gravel roads with open mouth carbs.

You don't want to scratch the bores and wreck the rings.

An if you find yourself on gravel be a ponzie.

One thing about open carbs is that kick is FAST and you need rear rubber on asphalt to hold on.
 
Ponzie = Don't Dance. Use your open mouth Carb Breganzie like a scooter on gravel and sand.

PS: Hope the right side don't walk froward if you don't lock that Nut over chain tension - Granted it's all by feel on the rear axel compression carrying the hub.
 
I should have added that when I pulled my top end off for the first time it had done 62,500 miles (100,000km) so would have been due for a rebore anyway. But riding Oz backroads and bulldust with no air filter was never going to help.

I love the airbox - I run big pods onto short tubes that fit neatly into the intake bellows. A bit of still air and weather protection, but plenty of Oxyjeen available! I reckon a track bike would be fine without, but if it swallows a load of kitty litter at redline ... fun fun fun!!  :o :o :o
 
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