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Re bore

Printed From: guzziriders.org - moto guzzi forum
Category: Technical
Forum Name: Loop Frames
Forum Description: Anything about the original Guzzi V Twin.
URL: http://www.guzziriders.org/forum_posts.asp?TID=9592
Printed Date: 28 Mar 2024 at 08:14
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Topic: Re bore
Posted By: PMVERN
Subject: Re bore
Date Posted: 02 Jan 2019 at 20:04
So, after buying my lovely 1968 V700 as a rideable classic, I started reading about the dreaded chrome bores.
To cut a long story short, it's rebore time.



I've phoned Langcourts about Nikersil coatings, seems pretty straight forward, but when I put new piston rings in, will they be compatible?
Also, has anyone on here done this? Any helpful advice will be gratefully received!

Thanks, Paul.




Replies:
Posted By: Glawster
Date Posted: 02 Jan 2019 at 20:12
Hi Paul,
I've just replaced the pistons and cylinders on my V7 Sport for the same reason.  I called Langcourt and they confirmed they could replate the bores with Nikasil, but the total cost of a Gilardoni kit with new pistons / rings / pins and cylinders was less than £600, so I went down that route instead.  If you do go the replating route I'm interested to hear how much it costs.


-------------
1970 Guzzi V7 Ambassador
1955 Guzzi Falcone Sport
2021 BMW R1250R
1998 Cagiva Gran Canyon


Posted By: Paul-l
Date Posted: 02 Jan 2019 at 21:30
hi Paul,
I've just had mine done by langcorts, it was about £120 per side + vat. They bored the cylinders to match the Pistons and rings that I had. I put a picture of them on the head stud broke thread a week or two ago.
I read somewhere that the original rings were compatible with the new plating so didn't need changing if they were in good condition.

Paul


Posted By: PMVERN
Date Posted: 02 Jan 2019 at 22:08
Thanks for the responses, the price on the Gilardoni kit seems reasonable,I'll post more details when I decide which way to go.
Sludge trap out next


Posted By: JayDee24ca
Date Posted: 03 Jan 2019 at 02:52
By the looks of the chrome in that bore, you may be well advised to check the lower end of the engine for damage  as well. Chrome is well known to destroy the bearings etc. Have you ad a look at the engine oil and inside the sump, for chrome specks? 
JD


-------------
74 Eldorado
74 Nuovo Falcone Militaire
79 G5
79 Convert
87 SPII
00 Quota 1100


Posted By: Loopian
Date Posted: 03 Jan 2019 at 09:57
I’m afraid by the look of those bores, I would expect the flaked off chrome to have gone through the rest of the engine.  I’m no expert but they look worse than on my Eldorado when I got it. I ended up rebuilding the engine completely. However it’s a very easy engine to rebuild, I got Nigel of NBS to rebuild the heads and regrind the crank. I put new bearings and seals throughout plus barrels and pistons etc, I took my time and had everything scrupulously clean.  I did it all indoors in the warm over last winter and really enjoyed it. Sorry that’s probably last thing you want hear, might be worth giving Nigel a ring at NB S.
Good luck
Ian


Posted By: oscar225
Date Posted: 03 Jan 2019 at 13:43
sorry to butt in on this thread, for the sake of us ignorant souls who are "NBS"?
Chris


Posted By: Barry
Date Posted: 03 Jan 2019 at 14:03
http://lmgtfy.com/?q=nbs+guzzi" rel="nofollow - http://lmgtfy.com/?q=nbs+guzzi

(o;


Posted By: Amboman
Date Posted: 03 Jan 2019 at 14:51
Unfortunately, there are no Gilardoni kits for V700s, haven't been for nearly a decade. Ambassador/V7 Special sets can be substituted, but their spigot needs to have the diameter reduced and there's a .5 mm difference in cylinder height as well.

For my V700 "Tutto Terrenco" project, I bought NOS piston assemblies and had Millennium Technologies replate the cylinders. Ended up costing virtually the same as what Gilardonis would.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 03 Jan 2019 at 18:49
Thanks everyone. I'm doing a total rebuild. Surprisingly, everything looks good, but I've yet to check tolerances.
I've talked to Gutsibits and was assured the 750 Gilardoni kit was a straight fit (apart from bigger gaskets). Looks like I'll be going down the Langcourt route
I'll report back after I've measured up next week.
Thanks again,
Paul.


Posted By: PMVERN
Date Posted: 12 Jan 2019 at 16:54
Hi all,
I had the callipers out last night, everything was pretty much in spec. The old girl's going to want new big end shells, and I'm going to purchase a pair of Asso 80mm pistons because one of the old piston skirts has a chunk missing (god only know what caused this to happen).


The barrels will be sent to Langcourt next week. I'm presuming the rings will work on nikasil the same as on chrome?
The advert for the Asso asks what weight you want the pistons (choice of 3 - a, b, or c) I'm thinking, as long as they are a matched pair, all should be well?
Emptied the sludge trap, hardly anything in it, result!



Thanks in advance for any feedback, this site is proving to be invaluable.

Paul.


Posted By: Dukedesmo
Date Posted: 12 Jan 2019 at 17:38
Currently waiting for some Ducati cylinders being replated. I'm getting them done by Poeton/Aptec as I have already had them replated twice by Langcourt only to fail both times.

That said I have had other cylinders done in the past by Langcourt without issue so maybe I was unlucky with this one...?


-------------
Le Mans 2
Ducati 916

Ducati M900


Posted By: Ken-Guzzibear
Date Posted: 12 Jan 2019 at 17:56
Cast rings work on all cylinders but Chrome only work with chrome therefore most aftermarket ones are Cast However one needs to run in cast rings in chrome/nigusil cylinders very carefully indeed

-------------
The Older i Get, The Better I Was


Posted By: JayDee24ca
Date Posted: 12 Jan 2019 at 19:51
I hope you are planning on turning the crank as well, and not just slipping in new bearings. That crank journal in the photo looks a tad rough. 
I wonder why the trap did not have more crud in it. Was this a low mileage machine? Or is there any sign it had been torn down before with perhaps the sludge trap emptied some time in the past? 
Have you thought about flushing the casing at all, to rid yourself of loose chrome bits? I would imagine the oil pump is toast as well by now. It looks as though there are chrome flecks in the sludge you removed, although that could just be the lighting.
JD


-------------
74 Eldorado
74 Nuovo Falcone Militaire
79 G5
79 Convert
87 SPII
00 Quota 1100


Posted By: Amboman
Date Posted: 13 Jan 2019 at 14:36
The rings that come with the Asso pistons will work on either chrome or Nikasil. You'll likely find that the new pistons are 10-15 grams lighter than the originals - the two sets I've bought were. I ended up having my crankshaft balanced as a result. On the other engine, I used a thicker piston pin to bring the piston assembly weight up to the original.

A, B or C doesn't really matter, but it is best to have a matched pair.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 13 Jan 2019 at 17:24
Thanks everyone. The crank and everything else are within tolerance. The way the engine pulled apart (with great difficultly), I don't think it's been apart for some time - if ever!
Great news Amboman about the pistons, I think this is the route I'll take.
Paul.


Posted By: PMVERN
Date Posted: 14 Jan 2019 at 19:39
Anyone know which piston choice would suit new Nikersil bores best A, B, or C. I'm guessing A, but I'd like a second opinion before I splash out.
Thanks,
Paul.


Posted By: PMVERN
Date Posted: 14 Jan 2019 at 19:43
Ignore previous post, found B stamped on the barrels


Posted By: Chris950s
Date Posted: 15 Jan 2019 at 09:01
The letter stamps on the pistons and bores are to match them in terms of tolerance so A pistons match A bores, etc. as long as they match there is no advantage as to which letter you have. 

-------------
Chris and Karen - Essex
2011 Stelvio NTX, 1974 950S (750S replica nearly rebuilt!), 1966 Triumph T100SS 58 years young this year!


Posted By: PMVERN
Date Posted: 15 Jan 2019 at 19:22
Thanks Chris, just packaging them up now.
Paul.


Posted By: PMVERN
Date Posted: 14 Apr 2019 at 19:02
3 months later and I've got everything for the rebuild.
I've been trying to find the torque settings for the early 700's. I can find the 750 ones, are they the same? Also, when putting the sludge trap plug back, it just keeps screwing in, I thread-locked it flush and peened it there. I hope this is the correct way.
I will include photos in my next post.
All responses appreciated, Thanks,
Paul.


Posted By: Dave P.
Date Posted: 15 Apr 2019 at 12:20
I would think that using the 750 torque settings you can't go far wrong.However, there will possibly be some variations and amendments,head nuts for instance.I would wait for Charlie (Amboman) to pick up on this thread and see what he says.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Amboman
Date Posted: 15 Apr 2019 at 14:04
Head nut torque is the same as the 750s and 850s - 29-32 ft. lbs.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 15 Apr 2019 at 19:00
Thanks for that, I'm starting the rebuild tomorrow, I'll get some pictures up.
Paul.


Posted By: Markru12
Date Posted: 28 Jun 2019 at 06:08
I am unfortunately in the same situation regards the cylinders on my 1967 v7
After a fair amount of research i will go the Gilardoni route with 83 mm bore (ambo )
I need to put a few questions out there. 
The casing bores are  92mm what is the external "spigot" diam of the ambo cylinders??
The original 700 cc heads can be used??
What changes need to be made to gaskets both lower and top??
I understand that there is a barrel height difference between the 700cc and ambo by .5mm
does this get removed from the new ambo cylinder or have to be added and if so is this accommodated in the gasket??
The ambo has different valve sizes to the 700cc will this make a big difference if 700 are retained??
Battling to get V7 valve guides any info on this??
Hope someone can assist.

Have a great day
Mark



-------------
HPH


Posted By: PMVERN
Date Posted: 30 Jun 2019 at 21:04
Hi Mark,
hope the rebuild goes well.
Mines coming on well, a bit slow, because I ordered the wrong size big end shells (gutsibits have been great).
I'll get the rest of my photos up when I get back of my holiday (Stella Alpina rally)
cheers,
Paul.


Posted By: Amboman
Date Posted: 01 Jul 2019 at 13:50
Originally posted by Markru12 Markru12 wrote:

I am unfortunately in the same situation regards the cylinders on my 1967 v7
After a fair amount of research i will go the Gilardoni route with 83 mm bore (ambo )
I need to put a few questions out there. 
The casing bores are  92mm what is the external "spigot" diam of the ambo cylinders??
The original 700 cc heads can be used??
What changes need to be made to gaskets both lower and top??
I understand that there is a barrel height difference between the 700cc and ambo by .5mm
does this get removed from the new ambo cylinder or have to be added and if so is this accommodated in the gasket??
The ambo has different valve sizes to the 700cc will this make a big difference if 700 are retained??
Battling to get V7 valve guides any info on this??
Hope someone can assist.

Have a great day
Mark



I'll have to do some measuring of the case and Ambo cylinders.

Yes, V700 heads will work fine. The first of the Ambassadors were basically V700s with 3 mm larger bores - same head with small valves and single springs.

You will need Ambassador/Eldorado (V7 Special/850GT) base and head gaskets.

If anything, the smaller V700 valves seem to make the engine a bit more "torquey" at the expense of top-end power.

Use the valve guides from later models, the retaining rings aren't used.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: Markru12
Date Posted: 01 Jul 2019 at 17:23
Great thanks Charlie.
This is good news i can now order the appropriate parts

Appreciate your input
Best regards

Mark


-------------
HPH


Posted By: Markru12
Date Posted: 07 Jul 2019 at 09:30
Busy with gearbox 4 speed 1968 
Shimming gone well and seems to be coming together
Have not factored in the rear cover gasket thickness(appears that will have no real effect/so thin)
What should the end float/backlash be on the lay shaft/output i currently have .4mm
The clutch shaft has an end  float of .25mm
Are these to large and if so i presume i would have to use a shim behind the bearing on rear case???

Regards

Mark


-------------
HPH


Posted By: PMVERN
Date Posted: 20 Aug 2019 at 20:56
Back from holidays.
Engine now running, needs fettling and the charging system needs sorting.
Working on trying to stop the SS1 from dripping too.( I read a original road test and they leaked from new).
Fun and games with the new dynamo belt and clutch cable, both been too short.
I'm also going to try and improve the truly awful front brake, but at least the old girl's running again.
Photos below as promised,
Cheers,
Paul.

























Posted By: Brian UK
Date Posted: 20 Aug 2019 at 21:09
Just a minor strip down then. Big smile


-------------
Brian.

Better 5 minutes late in this world than years early in the next.


Posted By: Dave P.
Date Posted: 20 Aug 2019 at 21:30
Great photo's. Another Loop lives! Well, nearly. Best of luck with the charging system, you're nearly there.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: iansoady
Date Posted: 21 Aug 2019 at 10:12
Another JB weld enthusiast I see!


-------------
Ian
1952 Norton ES2
1986 Honda XBR500
1958-ish Greeves/Triumph in progress


Posted By: Mike H
Date Posted: 21 Aug 2019 at 16:23
Very good. Thumbs Up

What's a "SS1" ?




-------------
"Chicken nuggets don't dance on a Tuesday."


Posted By: Dave P.
Date Posted: 21 Aug 2019 at 16:40
Originally posted by Mike H Mike H wrote:

Very good. Thumbs Up

What's a "SS1" ?



SS1 Dellorto remote float chamber carb' sir. Visible in the last pic'.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Mike H
Date Posted: 21 Aug 2019 at 17:04
That's great, I still wouldn't have known that's what it's called tho. LOL





-------------
"Chicken nuggets don't dance on a Tuesday."


Posted By: PMVERN
Date Posted: 21 Aug 2019 at 20:05
thanks everybody. We've certainly put the hours in.Just waiting for my mechanic
to get back off his holidays now


Posted By: PMVERN
Date Posted: 14 Oct 2019 at 20:39
So, I've made it back on the road - finally!



However, not without some niggly problems....The charging system is sorted, but I can't get the carbs to run properly... and I certainly daren't light a match anywhere near it!
Does anyone know where there are any later model carbs for sale? The SS1's I fear are worn out. I don't really want to buy new ones, as I would like to keep the airbox.
Any help or suggestions much appreciated.
Cheers

Paul.


Posted By: Amboman
Date Posted: 15 Oct 2019 at 14:05
If nothing else, they can be found on ebay.

http://www.ebay.com/itm/Dellorto-VHB29-VHB-29CS-29CD-Carburetors-Moto-Guzzi-Ambassador-Eldorado/372800722935" rel="nofollow - http://www.ebay.com/itm/Dellorto-VHB29-VHB-29CS-29CD-Carburetors-Moto-Guzzi-Ambassador-Eldorado/372800722935

Best to buy the VHB manifolds as well - the curve is slightly different than those for the SS1s.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 15 Oct 2019 at 19:57
Thanks for that Amboman, they look pretty good, I think I'll buy those.
Paul.


Posted By: Mike H
Date Posted: 17 Oct 2019 at 21:08
Originally posted by PMVERN PMVERN wrote:

So, I've made it back on the road - finally!


Thumbs Up



-------------
"Chicken nuggets don't dance on a Tuesday."


Posted By: PMVERN
Date Posted: 02 Dec 2019 at 19:01
thanks Amboman for spotting the VHBs, just rebuilt them including the plastic filters in the banjos. Can anybody suggest a way of stopping the banjos from leaking (really pouring out). I followed Greg Benders suggestions, but it didn't help.
Thanks,
Paul.


Posted By: Amboman
Date Posted: 02 Dec 2019 at 21:12
Originally posted by PMVERN PMVERN wrote:

thanks Amboman for spotting the VHBs, just rebuilt them including the plastic filters in the banjos. Can anybody suggest a way of stopping the banjos from leaking (really pouring out). I followed Greg Benders suggestions, but it didn't help.
Thanks,
Paul.

If they are metal banjos, you need an M6 fiber washer under the head of the bolt securing them. If you already have those, make sure the filters are fully seated into position. Also, the banjos are supposed to have a "ridge" where they contact the filter, many times this is corroded away or carelessly removed, resulting in a leak.  


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 03 Dec 2019 at 18:53
I've got the M6 washer in place. I've put a fibre washer between the banjo and filter and it seems to have sorted it (fingers crossed).
I now think I need a different pair of carb. manifolds, the ones that came with the carbs. are off a 1972 750,I'd hoped these would work as they are different to the ones off the SS1s, but airbox to carbs. will not line up. One step forward and two back at the moment, I suppose that's what winter nights are for.
thanks'
Paul.


Posted By: Amboman
Date Posted: 04 Dec 2019 at 14:15
Originally posted by PMVERN PMVERN wrote:

I've got the M6 washer in place. I've put a fibre washer between the banjo and filter and it seems to have sorted it (fingers crossed).
I now think I need a different pair of carb. manifolds, the ones that came with the carbs. are off a 1972 750,I'd hoped these would work as they are different to the ones off the SS1s, but airbox to carbs. will not line up. One step forward and two back at the moment, I suppose that's what winter nights are for.
thanks'
Paul.


It shouldn't be necessary to put a fiber washer there - the banjo is designed to seal on the filter. Perhaps too long of a bolt is fitted and it's bottoming out before everything seals?

If the manifolds are from a "72 750" then they should be the correct angle. There are two different rubber boots for SS1s and VHBs and they're not interchangeable. If you're trying to use the SS1 boot with VHBs, then it won't work.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 06 Dec 2019 at 19:05
according to my V700 parts book, the airbox boot to the VHBs is still the offset one, but seeing as it doesn't line up I've ordered the later one, fingers crossed.
I'll double check those banjo bolts though.
Thanks,
Paul.


Posted By: Amboman
Date Posted: 07 Dec 2019 at 14:27
The airbox boots - SS1 vs. VHB - are considerably different.

SS1:
http://www.mgcycle.com/images/atrex/12114300.jpg" rel="nofollow - http://www.mgcycle.com/images/atrex/12114300.jpg

VHB:
http://www.mgcycle.com/images/atrex/12114301.jpg" rel="nofollow - http://www.mgcycle.com/images/atrex/12114301.jpg



-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 03 Apr 2020 at 20:13
haven't posted for a bit. Done about 1000 miles since rebuild, carbs spotted by Amboman have been good, thanks for that.
Now the issue I've got is a nasty noise under load. The bike was still running sweet, I nearly convinced myself it was the belt ( I was having issues with that too). But I took the belt off and the noise was still there .
To cut a long story short, the big ends and crank are heavily scored, there must of been some hidden crap somewhere that caused this. I'm going to need +3 or +4 oversize shells but can't find any. Anyone know of any.
Thanks,
Paul.


Posted By: Markru12
Date Posted: 04 Apr 2020 at 14:34
sorry to hear about the scoring Paul
I will also need +3 shells for one of my cranks does not quite clean up on the crank pin with +2,s
I see they are listed on MG Cycles but seems to only be on special order.
Should you locate please keep me informed and i will do same.
In Lock Down in South Africa currently 31 degrees out side .
Thank heavens for swimming pool.
The last 2 days have built a v7 motor busy doing valve timing currently

Cheers

Mark


-------------
HPH


Posted By: Dave P.
Date Posted: 04 Apr 2020 at 14:42
Harpers in the USA list them.[URL= ][/URL] http://www.harpermoto.com/parts-lookup/pre-1980-moto-guzzis/ambassador-68-72/connecting-rods-crankshaft-piston-timing-gears-en.html" rel="nofollow - http://www.harpermoto.com/parts-lookup/pre-1980-moto-guzzis/ambassador-68-72/connecting-rods-crankshaft-piston-timing-gears-en.html

No guarantee that they are in stock though.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Dave P.
Date Posted: 04 Apr 2020 at 15:06
http://www.thisoldtractor.com/moto_guzzi_loopframe_oil_filter_addition_-_steve_odell-s_filterless_oil_filter.html" rel="nofollow - http://www.thisoldtractor.com/moto_guzzi_loopframe_oil_filter_addition_-_steve_odell-s_filterless_oil_filter.html

This is something to consider. I have done this to both of my Loops as they have no oil filter. It only traps ferrous particles but it must be better than nothing. Could usefully be used on the filterless 850T as well.

How does the oil pump look?

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Markru12
Date Posted: 04 Apr 2020 at 20:38
great will give them a go in new week.
Appreciate input
Mark


-------------
HPH


Posted By: PMVERN
Date Posted: 05 Apr 2020 at 18:15
Hi,
thanks Dave,I'll try Harpers. I'm going to fit a new oil pump.
The magnet looks a good idea.
Hello Mark, yes, this lock down is making things awkward. We've had 20 degrees today, but no pool . It's a shame the bigger shells are hard to get.
Cheers,
Paul.


Posted By: PMVERN
Date Posted: 09 Apr 2020 at 19:28
It looks like my crank is not going to clean up enough even for the plus 4 shells. Anyone got a spare they want to sell or know of one for sale.
(long shot I know)
Paul.


Posted By: Dave P.
Date Posted: 09 Apr 2020 at 20:46
https://www.ebay.co.uk/itm/Moto-Guzzi-V700-Ambassador-Crankshaft-Crank-Shaft/273071431213?hash=item3f94535e2d:g:MdIAAOSwa~BYQKWy" rel="nofollow - https://www.ebay.co.uk/itm/Moto-Guzzi-V700-Ambassador-Crankshaft-Crank-Shaft/273071431213?hash=item3f94535e2d:g:MdIAAOSwa~BYQKWy

It may be worth checking this one out.

Or this one.
https://www.ebay.co.uk/itm/Moto-Guzzi-V7-special-1970-crankshaft/273466186853?hash=item3fabdadc65:g:Kc4AAOSw0VZbn1ZO" rel="nofollow - https://www.ebay.co.uk/itm/Moto-Guzzi-V7-special-1970-crankshaft/273466186853?hash=item3fabdadc65:g:Kc4AAOSw0VZbn1ZO

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Dave P.
Date Posted: 09 Apr 2020 at 21:00
The second one is for a 750 Ambassador. Part No 12 06 42 01

The first one is for a 700.            Part No 12 06 42 00

I don't know what the difference is, they are only one digit apart and I'd be reasonably confident (Places head in a noose )that either one would do. However, I'm hoping Ambo Man will pick up on this and either confirm my suspicions or shoot me down in flames.

Further investigation shows that 12 06 42 01 will fit V700 or 750. According to the Stein Dinse parts list.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Amboman
Date Posted: 10 Apr 2020 at 14:29
Yes, either should work. Same stroke. 

-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 11 Apr 2020 at 19:14
Excellent, thanks guys. I'd seen the one in the states, but not the other one.
I'll get in touch with the seller and see if he'll measure it up for me.
Cheers, Paul.


Posted By: Dave P.
Date Posted: 19 Apr 2020 at 14:01
Any joy with the crankshaft ???

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Richard Hyatt
Date Posted: 19 Apr 2020 at 15:56
If you cranks are scored deeper than the max regrind, then can you not get them built up and reground back to standard ?
I seem to remember a process like this year's ago .
Have you tried any engine reconditioners near to you , they may know of this process.
Edit
I think it was very heavy chromed and machined back or welded and machined back , I can't remember, but a really decent engine place may know , one of the old school places.
Edit
Quick search        https://bguk.co.uk/our-services/" rel="nofollow - https://bguk.co.uk/our-services/


Posted By: Dave P.
Date Posted: 19 Apr 2020 at 16:27
https://www.lcandm.co.uk/crankshaft-refurbishment/" rel="nofollow - https://www.lcandm.co.uk/crankshaft-refurbishment/
As Richard said.
Hard chroming or plasma spraying could be the answer if replacement isn't straight forward.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: PMVERN
Date Posted: 20 Apr 2020 at 17:44
I've been trying to get in contact with the guy selling the crank on e. bay from Germany. I've heard nothing back, I'm presuming lockdown.
Thanks for the suggestions of having mine built up, I've been in touch with SED at Kegworth and they will do it for me (phew).
Thanks for all the help and I'll keep you updated,
Paul.


Posted By: Dave P.
Date Posted: 20 Apr 2020 at 17:52
That's good news. What is the condition of the main bearings, are they still good?

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Richard Hyatt
Date Posted: 20 Apr 2020 at 18:31
At least retaining your own crank , building it up and bringing back to std shell brings a whole new lease of life to it and of course originality.
Glad you have a solution now


Posted By: PMVERN
Date Posted: 23 Apr 2020 at 19:05
Mains are still good. I'm having it plasma sprayed, as mentioned, at least it keeps it original. Posted it off to SEP at Kegworth, quoted £150 which I thought was reasonable.
Cheers,
Paul.


Posted By: Richard Hyatt
Date Posted: 23 Apr 2020 at 19:45
Glad sorted , start from new again


Posted By: Dave P.
Date Posted: 23 Apr 2020 at 19:46
Great stuff!

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: PMVERN
Date Posted: 07 Jul 2020 at 22:19


So, I got the crank back - it looks good, however, there was a bit of a communication issue and mains were done as well as the big end! More seals ordered and another three week wait!.... then realised the UJs are knackered too, £220!!. Found Propshaft parts on Ebay £64 the pair, result!

Anybody know where to get any tab washers for the conrods?

Thanks,
Paul.


Posted By: Dave P.
Date Posted: 07 Jul 2020 at 22:44
I think I got mine from Gutsibits along with B/E bolts and nuts.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: PMVERN
Date Posted: 15 Sep 2020 at 19:29
Got the bike finished at last, seems good at the moment, done about 300 miles with plenty of oil changes (again).
to try my patience today, its covered my rear wheel with oil I think its gearbox, but I cant figure where its come from.
all suggestions and guesses most welcome.
Thanks Paul.


Posted By: Dave P.
Date Posted: 15 Sep 2020 at 22:09
Have you tried smelling the oil? Gearbox oil smells different to engine oil. Have you checked the gearbox breather and the actual oil level in the gearbox? Has it been over filled? Then of course there is the large seal on the bevel box. Lots of places to choose from.
Best of luck.

I presume you did fit a hose to the gearbox breather. I'm sure I read something about Guzzi not doing so at first then deciding that it would be a good idea.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: c13pep
Date Posted: 16 Sep 2020 at 10:35
The simple rule I follow is that if the oil on the tyre is like a `sunburst` then its at the backend ie. bevel box, brake caliper etc. if it`s covering the tyre then engine and gearbox are culprits. I can empathise with the phrase `trying my patience` but that sums up owning an older Guzzi as I to am trying to locate a very small weep on my MonzaOuch 

CHRIS


-------------
you can`t have any fun in a straight line

Monza
Honda CB77 project



Posted By: PMVERN
Date Posted: 16 Sep 2020 at 19:23
Thanks for the replies
Interesting about the sunburst oil fallout. That's what it looks like.
It seems to be leaking from the shaft to bevel joint, but its never leaked from there before, and that oil has been in there for about 1000 miles.
I'm going to have a proper look Friday.
Thanks again,
Paul.


Posted By: PMVERN
Date Posted: 27 Sep 2020 at 18:54



Bag full of tools on the back
Just done another 500 miles, bevel has leaked a bit again, but not as much as before, no breather on these early ones, but I'm thinking of fitting one.
Now she's up and running, I'm going to change the very old rubber to some TT 100s, nice and classic looking. Also a change of fork oil.
I would like to have the original shocks rebuilt to keep the originality.
I've done a compression check, all good, but I find the engine braking poor, is this normal?
cheers,
Paul.


Posted By: Dave P.
Date Posted: 27 Sep 2020 at 22:19
I've done a compression check, all good, but I find the engine braking poor, is this normal?   


I think that's probably down to one of motorcycling's heaviest flywheels.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Amboman
Date Posted: 28 Sep 2020 at 14:08
The rear drive vents through the transmission in theory. I've never found the need to add one to the rear drive. None of the Loop (or Tonti)rear drives came with a vent from the factory. I do "burp" the rear drive though - get it up to operating temp, remove the fill plug, replace the fill plug.

Don't over fill it - only 180 cc total.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: Mike H
Date Posted: 28 Sep 2020 at 19:24
Originally posted by Dave P. Dave P. wrote:

I've done a compression check, all good, but I find the engine braking poor, is this normal?   


I think that's probably down to one of motorcycling's heaviest flywheels.


I didn't have a loop frame model, but that reminds me, I noticed several times that my 850 Tonti braked quicker if I pulled the clutch as well. Big smile




-------------
"Chicken nuggets don't dance on a Tuesday."


Posted By: PMVERN
Date Posted: 28 Sep 2020 at 19:28
Thanks Dave, I thought a heavy flywheel meant better engine braking
And thanks Amboman, I've burped the bevel twice, but never measured it in dead accurate, just waited till it appeared at the level plug. I'll be more precise next time and see if it helps.
Cheers, Paul.


Posted By: PMVERN
Date Posted: 28 Sep 2020 at 19:31
Tonti brakes are better than loop brakes.


Posted By: Dave P.
Date Posted: 28 Sep 2020 at 22:27
The Loop flywheels weigh over 13 pounds and that's without the ring gear and the clutch components, plus the weight of the massive spinning crankshaft.For comparison the LM1 flywheel assembly weighs little more than half that of your Loop.
I weighed the flywheel assembly of a Panther M100 that I used to have many years ago and that must have been the daddy of 'em all, just shy of thirty pounds.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Dave P.
Date Posted: 28 Sep 2020 at 22:52
Originally posted by PMVERN PMVERN wrote:

Tonti brakes are better than loop brakes.


Not in the wet they ain't.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: PMVERN
Date Posted: 29 Sep 2020 at 19:01
'm just pleased that's how they are. My previous Guzzi history- Cali EV, Centauro, modern V7,all had strong engine braking.
The new rubber looks a bit lost, downsized from 120s to standard. I'm sure it'll handle better
Shockers next, rebuild or refresh. What are you guys running?
Cheers Paul.


Posted By: Dave P.
Date Posted: 30 Sep 2020 at 23:30
If you find anyone who will/can rebuild the original shocks please let us know. In the meantime, Ikons seem fine on both of my Loops, they were already fitted when I bought the bikes. Hagons should be fine and somewhat cheaper. Hagon will fit the correct springs to suit your requirements if you ask them to.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: Amboman
Date Posted: 01 Oct 2020 at 14:21
Ikon has a line of less expensive shocks called "Basix". Non adjustable damping, adjustable spring preload only. But, they're very good quality and rebuildable. Actually priced less than Hagons cost in the US. I've installed a few sets on customer's Loops and they all seem happy with them. 

-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 02 Oct 2020 at 18:11
Thanks again Amboman, had a look at the Ikons, liked them, ordered them
The correct size rubber might not look as good, but it sure makes the old girl agile. Had another nice 100 mile ride again, all good at the mo.
Cheers, Paul.


Posted By: PMVERN
Date Posted: 07 Nov 2020 at 19:39
Thought I'd post an update seeing as no more riding for the next month
Really pleased with the Ikon shocks (thanks again Amboman). The old girl's running well-thank the gods.
I've got a couple of annoying oil leaks, one from the bellhousing breather and one from the clutch pushrod (I replaced the o rings). But these are minor niggles after two engine rebuilds .Any one got a nice mirror they want to sell me?

Anyway here's a photo.



Posted By: Dave P.
Date Posted: 07 Nov 2020 at 23:22
Excellent, nice to see another Loop on the road.
I'm not sure what you mean by the "Bell housing Breather"

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: james58
Date Posted: 19 Nov 2020 at 08:05

Hi Amboman,

A question to you I have a 1971 750 that I am reviving, most of the insides where very good it has cast iron bores however after cleaning the pistons there was a lot of pitting on top and to the sides the engineer said maybe change them as the ones on the side are bothersome . So Gilardonis ? no as all shops I have tried are out of stock and the company itself doesn't know when and if they will be available. I came across some new asso pistons I am wondering if they are compatible I think only the A's are available . I am trying to find specs on the Asso's however not finding much luck, so I am trying here. Is there any info that you could share that might be beneficial for my dilemma ?

Thanks James


Posted By: Amboman
Date Posted: 19 Nov 2020 at 16:55
Asso makes excellent quality pistons. The "A" is a size grading due to small variances in diameter. Is there a letter stamped into your present pistons? It should be somewhere on the crown.

The other consideration is to make sure they are V7 Special/Ambassador pistons and not 850GT/Eldorado pistons. They have the same 83 mm diameter, but the compression height (distance from the pin to the crown) is 4 mm different. Also, the Ambassador pistons have a domed crown and the Eldorado pistons have a raised flat top.

Mark Etheridge @ Moto Guzzi Classics in California sells forged CP Pistons that he had made to spec. They are slightly oversized to accommodate cylinders that have been damaged. Not inexpensive, but very high quality. If interested, call him at 562-986-0070.


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: james58
Date Posted: 19 Nov 2020 at 19:54
Hi
Thanks for that, they are domed . Another question what would installing these pistons do to the balance of the engine is there anything else I should know ? Apparently they are matched with Kenig pins and they have rings and clips supplied . Have you heard anything of the re-manufacturing of Gilardonis and is there another outlet that still sells Asso pistons in case the measurement of cylinders require a B or C rather than a resleeve  if at all needed? I have also contacted Mark I will await his reply.

Thanks for your info muchly appreciated . I hope your country can find its peace.

Thanks James


Posted By: Amboman
Date Posted: 20 Nov 2020 at 14:09
It would be best if the replacement piston assemblies weighed the same or very close to the same as the original piston assemblies. In the case of my V700, the Asso pistons were slightly lighter than original. I had the crankshaft rebalanced partly due to that.

I haven't heard anything about when Gilardonis will be available again. I get the feeling it could be quite some time.

Asso pistons have been available on ebay via seller "valtermotousa", but it seems his stocks are dwindling. I don't know of another source, but it might be worth contacting this company: http://www.thekingofpiston.com/index.php?lang=en" rel="nofollow - http://www.thekingofpiston.com/index.php?lang=en


-------------
Charlie
'69 Ambassador,'71 Ambassador,'73 Eldorado,'75 Eldorado police,'76 Convert,'77 Morini 3 1/2 Strada,'81 Ducati 500SL Pantah

http://www.AntietamClassicCycle.com


Posted By: PMVERN
Date Posted: 18 Apr 2021 at 19:47
I hope you're all managing to get out on your Loops now we've got a little more freedom.
I've managed 1500 miles since the second rebuild, and all's well apart from various oil leaks. The one that's foxing me the most appears to be coming from around the exhaust area, it's not the head gasket. Has anyone had similar issues.
Cheers'
Paul.


Posted By: Paul-l
Date Posted: 18 Apr 2021 at 20:55
I’ve had the oil feed banjos weeping on mine - that runs down in that kind of area
But perhaps there’s a split on the head allowing oil from the rockers through?


-------------
Paul

V7 Loop and a V35 to look after


Posted By: Ken-Guzzibear
Date Posted: 19 Apr 2021 at 08:11
Not familiar with loops do they have the blanking plug in the head as per the Tonti bikes? That oil ring around the blanking plug kinda opposite the plug can fail getting oil around the head, the copper washers on the oil feed need annealing had to do mine twice. 



-------------
The Older i Get, The Better I Was


Posted By: Dave P.
Date Posted: 19 Apr 2021 at 09:48
Yes, loops do have the blanking plugs which can be a source of leakage. A fresh crush washer and a lick of Wellseal on the threads soon stops that.

-------------
TO LIVE OUTSIDE THE LAW YOU MUST BE HONEST.

1971 V7 Special. 1972 850GT.
1970 T120 Bonnie. 2009 500 Bullet.


Posted By: PMVERN
Date Posted: 19 Apr 2021 at 19:17
I'll check out the blanking plug, I never thought of that.
The banjos are fine, and as for the split head, I hope not.
cheers, Paul.


Posted By: PMVERN
Date Posted: 27 Nov 2021 at 15:15
It's has been a while since I last posted, the main reason is because the bike has been running well.
As regards the last problem, it was the blanking plug, I just popped a new o ring on, problem solved
I was just wondering if anyone has fitted Greg Benders wiring loom, it is certainly a quality item and looks very straight forward. I also got his additional relays that protect the starter circuit.
Cheers, Paul.


Posted By: Ken-Guzzibear
Date Posted: 28 Nov 2021 at 09:13
You would be surprised how many people ignore the blanking plug, think it is the rocker gasket and overtighten the rocker covers. 

That blanking plug leaking allows oil to go everywhere, a small amount of oil looks way worse that it appears.


-------------
The Older i Get, The Better I Was


Posted By: Paul-l
Date Posted: 28 Nov 2021 at 09:36
Yes, I’ve put one of Greg’s wiring looms on mine. Fitted a treat.
 I got him to add a few extra wires to it as my bike has indicators and a second pair of horns added at some point. It’s so much better than the twisted wire wrapped in insulation tape that most of the joints were before!

The light switch on mine he recommended using a conductive epoxy as the plastic can melt when soldering - it’s expensive but cures with a hair drier. If you want I could try posting enough to do those joints.


-------------
Paul

V7 Loop and a V35 to look after


Posted By: PMVERN
Date Posted: 03 Dec 2021 at 18:54
Hi Paul,
epoxy glue arrived today, thankyou very much
cheers, Paul.



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