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LOOP BRAKES.

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Dave P. View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 03 May 2020 at 22:27
Thanks Pete.
I'm going to dismantle the brake as soon as I have the use of my right hand (can't even see the knuckles at the moment!)just in case there is anything untoward. A detached lining for instance. I don't suppose there will be but...................who knows.
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Guzzis3 Quote  Post ReplyReply Direct Link To This Post Posted: 04 May 2020 at 03:42
I assume you know this but in case you don't...

When you reline shoes you should get them radius ground to match the actual diameter of the drum. It sounds like either the shoes were relined too low or somewhere in the process the arm was mis-positioned as is mentioned above.

People have been whinging about the drums on loops and V7 sports as long as I can remember. Brakes on all bikes were very different to today in the late 60's early 70's. These can be brought more in line with modern expectations by careful material selection and proper setup. The latter also applies to the suspension on loops, especially the fork. Most of the loops I've encountered over the years have terrible setups but I've ridden a few that were really done properly and it utterly transforms the bike. Comfortable, precise, laser like in corners and really pleasant braking.

I cannot recommend highly enough putting effort into the suspension and brake setup on a loop frame. It will transform the bike and you will fall in love with it all over again. Being a guzzi you might as well because there won't be any other repairs or maintenance to do...(Tell that to a ducati owner...)

finally my sympathies on the crash. I hope you and your bike recover well.


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GUZZIPETE View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote GUZZIPETE Quote  Post ReplyReply Direct Link To This Post Posted: 04 May 2020 at 08:28
Just wondering if you've had your hand looked at Dave?
1971 Moto Guzzi V7 Special
1974 Laverda 750 SF2
1979 Laverda 3CL

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red leader one View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote red leader one Quote  Post ReplyReply Direct Link To This Post Posted: 04 May 2020 at 08:33
I was wondering that as well.
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Dave P. View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 04 May 2020 at 08:45
Hi Guzzi3, Yes as you say I was aware of the brake arcing. These were not re-lined shoes however, just cleaned and de-glazed.
I'm interested in your comment about fork setup. Can you give details of your ideal setup, please.

The hand, no I haven't had it looked at. I'm sure it isn't broken 'cause I can wiggle my fingers, albeit whilst wincing a bit. I thought the NHS had better things to do at the moment than looking at a self-inflicted injury.
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
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Ben. View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ben. Quote  Post ReplyReply Direct Link To This Post Posted: 04 May 2020 at 08:55
Dave, I had a spill after which my arm was sore for two weeks. I could wiggle and grip so I thought it would heal. It just kept hurting.
The x-ray eventually revealed that I´d split the socket end of the ulna, so I got plastered after all.
(I´ve been getting plastered ever since).
Hope you get better news ...

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Post Options Post Options   Thanks (0) Thanks(0)   Quote ranton_rambler Quote  Post ReplyReply Direct Link To This Post Posted: 04 May 2020 at 13:04
My son broke his arm at school. It was only after a second visit to the doctor when it hadn't got better after 4 weeks that he was X-rayed. He does have good tolerance to pain!

I'm also interested in what can be done with loop forks. I didn't think there was anything that could be adjusted except the oil quantity and type. And keeping them in good order. Having said that, I'm pretty happy with mine - I ride like a granny and can still drag the sidestand on the road.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Guzzis3 Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 03:54
Originally posted by Dave P. Dave P. wrote:

Hi Guzzi3, Yes as you say I was aware of the brake arcing. These were not re-lined shoes however, just cleaned and de-glazed.
I'm interested in your comment about fork setup. Can you give details of your ideal setup, please.

The hand, no I haven't had it looked at. I'm sure it isn't broken 'cause I can wiggle my fingers, albeit whilst wincing a bit. I thought the NHS had better things to do at the moment than looking at a self-inflicted injury.

It's not my setup. There is a chap here in Brisbane who has had loops forever and he's done a lot of systematic experimenting on how to get them to behave. I THINK he runs very heavy oil in the fork, 120 or something, to get some dampening going. He also mentioned he'd found what he thought were the perfect lining materials for the shoes to lock the front wheel and have the rear just nice. When he does his he does the lot, dress the drum, radius grind everything set up properly.

I have ridden an 850GT restored by a really pedantic guzzi mechanic in Adelaide. I don't know exactly what he did to it but as a start he would have got the shocks rebuilt properly and the forks as new, good steering head and swingarm, everything straight. You might be surprised at how many "restored" guzzis aren't right in these areas. Shiny new paint isn't a restoration. Anyway the bike was an absolute joy to ride. Cornered on rails, adequate brakes. I don't use brakes much so I'm not the best person to ask. 

The loops give a real sense of occasion to every ride unlike the later tontis. I love my tontis but they aren't exhilarating in everyday situations like an 850GT is...maybe some day I'll finally pmfo and buy a disc braked 850GT/eldo.
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Post Options Post Options   Thanks (1) Thanks(1)   Quote ranton_rambler Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 07:44
We’re veering away from brakes, but I use 90 gear oil in my forks. This was a recommendation from Nick Adams in Canada. Seemed strange to me, but I looked into it. The workshop manual recommends an obsolete Shell hydraulic oil, Tellus 32 I think. Viscosity scales are different for engine, transmission and hydraulic oils but comparison tables can be found, and it turned out that 90 gear oil was pretty close to the original.
Ian

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Dave P. View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 09:54
Hi Damian. I seem to have found the ideal brake setup to lock the front wheel As for the forks I use ISO 68 hydraulic oil which is today's equivalent of Shell Tellus 32 and gives good damping. With regard to cosmetic restorations, I know.........I bought one then spent some time and money getting it right.I've owned two Tonti's and two Loops,all great bikes, but for me, the Loops have a certain something that makes me prefer them to all else.

Edited by Dave P. - 24 May 2020 at 11:30
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote GUZZIPETE Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 10:30
This is also useful info, as I haven't had the forks apart on my Loop yet in the 4 years I've had it. A combination of them performing reasonably well (though under-damped) and the challenging stories of getting them apart have caused me leave the job on the to-do list so far.
The Loops are a very different experience to the Toni's, well mine are anyway. The engine in the V7 Special is smoother and pulls more strongly and cleanly from low revs than the 850T. A loop with the 5 speed box (850GT) would be about as good as it gets I think? But of course all these old Guzzis' vary.

Pete.
1971 Moto Guzzi V7 Special
1974 Laverda 750 SF2
1979 Laverda 3CL

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Post Options Post Options   Thanks (0) Thanks(0)   Quote ranton_rambler Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 10:37
Originally posted by GUZZIPETE GUZZIPETE wrote:

This is also useful info, as I haven't had the forks apart on my Loop yet in the 4 years I've had it. A combination of them performing reasonably well (though under-damped) and the challenging stories of getting them apart have caused me leave the job on the to-do list so far.
The Loops are a very different experience to the Toni's, well mine are anyway. The engine in the V7 Special is smoother and pulls more strongly and cleanly from low revs than the 850T. A loop with the 5 speed box (850GT) would be about as good as it gets I think? But of course all these old Guzzis' vary.

Pete.

That might be the big flywheel. I'm in the middle of changing my clutch and have 3 sets of bits to select from. The best looking flywheel is a later (lighter) one so it will be interesting to see how that changes it.
Some people reckon the 4-speed box is better, but I've never ridden one.
Ian
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GUZZIPETE View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote GUZZIPETE Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 10:58
They do seem to spin up quicker and seem more lively with the lighter flywheel.
The 4 speed box on mine is OK, but is quite whiney, as I think most would agree they are. Mine was re-built by Nigel at NBS last year, but is pretty much the same in the whine dept.
Pete.
1971 Moto Guzzi V7 Special
1974 Laverda 750 SF2
1979 Laverda 3CL

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Dave P. View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Dave P. Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 11:24
Having got one of each,4 speed and 5 speed as you have Pete I prefer the 4 speed. The change seems a little smoother though there's not a lot in it. I also like the heavy flywheel, though they both have that. The 4 speed has a lower first gear which is nice in slow-moving traffic but of course, the 5 speed is an 850 with taller overall gearing so has the edge where high-speed cruising is concerned two-up with luggage.I suppose all this waffle means that either one will do the job equally well and I wish I was out on one now. Either one!!!!!!!!!
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.
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GUZZIPETE View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote GUZZIPETE Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2020 at 11:46
HA!, yes, too true Dave. Isn't your favourite bike the one you're riding at the time??
1971 Moto Guzzi V7 Special
1974 Laverda 750 SF2
1979 Laverda 3CL

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