Agusta's aweigh..!

weeveetwin

weeveetwin

New member
Hi guys

I've spent the day fitting the newly painted 'Sport' tank to my MV, and I have to say that now it's on there it looks more suited to the bike's 1970s styling than the 'SS' & 'America' tanks I've had on it previously.

So, it's finally sorted. It's now the mirror image of the bike that first sparked my yearning for an MV Agusta all those years ago in the mid seventies (the one on the cover of the Sept. '75 edition of Bike Magazine).

All's left wanting for it now is a new Borrani rim for the rear, and stainless spokes - but that can wait. Finally, it feels/looks like the MV I always wanted! :thumbs:


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Just right on so many levels!
Love the bank of carbs just peeping out. Balancing those will keep you amused I bet.
I picked up a Borrani on fleabay recently for not a lot of money. Surprising what pops up.
Have to make a point of seeing and (as Paul says) hearing this bike one day soon.
You should be pleased and proud of it. (her?)
 
At the time in the 70's I thought that MV's looked to flash but now it just looks fantastic. Well done.:)
 
Cheers guys.


PaulV: The actual exhausts aren't very loud, surprisingly. Nowhere near as loud as Termis, and quieter than my Duc. Most of the real racket comes from the carb. intakes and gear drive for the cams - so it only seems noisy from the rider's perspective (..mind you, this really is blood curdling when on the move. So much so that it physically hurts your ears. MUCH louder than my Ducati). (Nice F4 by the way ;) Another MV-isti!)


239desmo: The carbs are really very basic, and are not difficult to fettle. A piece of tubing pressed to your ear, and listen to the hiss from each intake - and Bob's yer uncle! (Ahh! Those were the days!)
Incredibly, they're only attached to their individual inlet stubs by short pieces of rubber hose and a hose clamp. The four of them can be removed in five minutes flat! (This simple rubber mounting also means they are actually pulled upwards by the throttle slide/throttle cables. Be toooo enthusiastic with the twist grip, and you might even pull the carbs. off!)


Scotty: Yes, I'll be taking it up to Hartside when the weather improves. It won't be on an organised run out though. I'd be left behind. She's 36yrs old, so I'll be 'bimbling' most of the time I'm aboard :o (..notice I said most of the time? :D )


Steve
 
weeveetwin said:
Incredibly, they're only attached to their individual inlet stubs by short pieces of rubber hose and a hose clamp. The four of them can be removed in five minutes flat! (This simple rubber mounting also means they are actually pulled upwards by the throttle slide/throttle cables. Be toooo enthusiastic with the twist grip, and you might even pull the carbs. off!)
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Can't remember the technical reason for being rubber mounted (something about the rubber mounting absorbing vibration and improving atomisation or something...Derek?) but had a problem with getting a bike to idle cleanly.
Turned out the clamp on the rubber mount had caused it to crack over time and it was drawing air through the rubber mount and running permanently lean. Could hardly see the hairline cracks in the rubber.:(
 
239desmo said:
Can't remember the technical reason for being rubber mounted (something about the rubber mounting absorbing vibration and improving atomisation or something...Derek?) but had a problem with getting a bike to idle cleanly.(
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This bike wouldn't idle at all when I got it. The previous owner put it down to the over-large carbs. Said it never had idled correctly. (..and this was after recently having been fettled/shimmed/tuned by the Kays).

All the same, I stripped off the carbs and examined everything. I soaked the rubbers overnight in brake fluid (it's good for rubber!) - and spent much time after re-assembly synchronising throttle slides and fiddling with the air screws. The result is it will now idle, but it has to be fully hot. (..and if ever it won't, it's no prob. Gives a chap a good excuse for 'blipping' the throttle at stop lights, eh?!) :lol2:
 
weeveetwin said:
The previous owner put it down to the over-large carbs. Said it never had idled correctly. (..and this was after recently having been fettled/shimmed/tuned by the Kays).
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Had a similar problem with a supposed over large carb on the bike.
Would start first or second kick from cold and would run for 20 seconds before conking out unless blipping the throttle and then when fully hot she would idle/start fine. Half warm it was a nightmare. After much trial and error procedure was kick her over on full choke once, close the choke and a hint of throttle and she would fire on the next kick. Great fun at lights which have turned to green and angry motorists behind!:comp2:
Developed technique of starting her and immediately riding off gently and hoping no need to stop for a few minutes.
Always will be a compromise with that type of bike......but that gives them character.:)
 
Beautiful bike. When I see such a gorgeous design it makes me ask myself all over again why so many manufacturers today seem to think the way forward is cartoon 'design'
 
weeveetwin said:
This bike wouldn't idle at all when I got it. The previous owner put it down to the over-large carbs. Said it never had idled correctly. (..and this was after recently having been fettled/shimmed/tuned by the Kays).
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Oversized carbs shouldn't affect the idling, after all the slide is virtually closed. The effect of carbs that are too large is that at wide open throttle the gas velocity is too slow to vaporise the fuel properly. The engine can only draw so much air, determined by the valve sizes, cam lift and porting, so there is an optimum size for the carburetor. Too small and the incoming air is restricted and hence performance. Too large and the air velocity through the venturi slows down and presumably doesn't pull enough fuel through the main jet. I'm not sure about the exact effects, it's a while since I read up on this sort of thing, but you get the idea.
The reasons for rubber mounting the carbs are to isolate them from the engine heat and vibration.
I'm not so sure about the notion of pulling the carbs off by winding the throttle open, after all the cable outer is normally stopped against the carb so the cable is only pulling one bit of the carb (the slide) against another bit of the carb (the body) unless the MV has some peculiar cable linkage. :confused:
 
weeveetwin said:
Cheers guys.

(Nice F4 by the way ;) Another MV-isti!)


Steve
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Steve, there are significant differences, you have spent a whole lot of time, money and effort to get your bike to it's stunning condition. I was lucky enough to find a low miler that had been well looked after.... Luck against effort, you have my respect, as does anyone who keeps these classics in mint condition. I doth my cap:hail: :hail: :hail:
 
Derek said:
Too large and the air velocity through the venturi slows down and presumably doesn't pull enough fuel through the main jet. I'm not sure about the exact effects..

I'm not so sure about the notion of pulling the carbs off by winding the throttle open, after all the cable outer is normally stopped against the carb so the cable is only pulling one bit of the carb (the slide) against another bit of the carb (the body) unless the MV has some peculiar cable linkage. :confused:
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Hi Derek

The larger carbs have the effect of reducing torque at low revs (as you say, it weakens the mixture a little).

The throttle cable (outer) doesn't bear on the carb caps with these early MVs. Instead, one cable operates through a fulcrum on a set of four metal lifters which hang directly above the throttle slides (like four separate crane jibs!) These pull directly up on the throttle slides, and thus exert upward lift on the carbs themselves. The only thing stopping you pulling the carbs off with the throttle is the positive stop on the cable/twistgrip. My remark was really a bit tongue-in-cheek. (All the same, the carbs can be see to lift on their mounts when the twistgrip is turned!)

This is the only photo I could find with which to illustrate:
 
weeveetwin said:
The throttle cable (outer) doesn't bear on the carb caps with these early MVs. Instead, one cable operates through a fulcrum on a set of four metal lifters which hang directly above the throttle slides (like four separate crane jibs!) These pull directly up on the throttle slides, and thus exert upward lift on the carbs themselves. The only thing stopping you pulling the carbs off with the throttle is the positive stop on the cable/twistgrip. My remark was really a bit tongue-in-cheek. (All the same, the carbs can be see to lift on their mounts when the twistgrip is turned!)
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I see what you mean :D
 
...I hate you weevtwin!!!!!! :p

Stewart, I thought rubber mounted carbs were in an effort to stop the heat transfer from the heads to the carbs causing fuel vapourisation.

I got a mate with one of these down south, the sound is truly wonderful.

:)
 
rockerted said:
steve, when you go to hartside, give me a shout, cos at my age i bimble a lot as well..!!:)
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Will do Ted.

I too tend to bimble along (whatever bike I'm on) - which is why I ride alone most of the time. I spend much of my time just admiring the scenery, and I get passed by Goldwings and all kinds.

Truth is, I've outgrown having to compete, and I don't feel the need to prove my 'riding prowess' :rolleyes: by going fast. I've not dropped a bike in thirty years of riding - and this, to me, is proof enough I'm doing ok.
 
Blimey that's a nice bike !
I'll never forget the first time I saw one. I was at Croft in 1978 on my FS1e. I'd only ever seen pictures of an MV in mags and the sight and sound of one of these bikes was unbelieveable.
Nice to see you are going to ride it and not lock it away :)
 
its looking really nice Steve, reminds me of one I saw early 70's, think it was at the show they had at the Horticultural Halls in London, it started my interest in Italian bikes.

Stewart, you'll find on the Monty thay you've got solid carb mounts, the rubber ones that came as standard are always removed, the metal ones are meant to improve things.
 
Glass and hand and oil for checking rubber inlets.
With glass on flat bench, wet the glass with a smidgen of oil, place one open end of rubber on the oily glass then use the palm of your hand to push down on the inlet opening and the rest is physics as they say.
Should be a vaccuum to keep the glass firmly under the rubber as you lift it a little.
Saw me Dad do it years ago.

Love the MV but I'd probably be too scared to take leave it anywhere near grubby fingers in car parks.
 
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