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V50 first ride and an electrical query

Printed From: guzziriders.org - moto guzzi forum
Category: Technical
Forum Name: Small Blocks
Forum Description: V35 up to V750 including Breva750, V7, V9 and new V85.
URL: http://www.guzziriders.org/forum_posts.asp?TID=10522
Printed Date: 28 Mar 2024 at 13:42
Software Version: Web Wiz Forums 12.03 - http://www.webwizforums.com


Topic: V50 first ride and an electrical query
Posted By: George
Subject: V50 first ride and an electrical query
Date Posted: 16 Sep 2019 at 18:08
Hello - I've had the first ride on the V50 mark 2 and it's quite a lot different from either my LE Velo or Honda CD175. I ran the bike for about 2 miles yesterday and when I returned home set about synchronising the carbs. After installing the vacuum gauges I tried to start the bike but it then appeared that there was insufficient power in the battery to turn the engine over. The solenoid could be heard trying to kick in, the console lights were all noted to be dim. The main beam headlight bulb would not light but the winkers functioned OK. The battery showed around 12 volts at the time (I think). All fuses were OK and not any smell of burnt wiring. I have had the battery checked today and it was considered to be in good condition after a boost charge (around 13 Volts and 399 cranking amps). I have used a good quality clip on ammeter and with the ignition on there is no indication of a heavy draw
(meter reading only 0.4 of an amp supposedly from the instrument warning light). The bike does currently does fire /run up OK (although there is a misfire on the left hand cylinder to sort out). After reading previous posts on the forum I am about to start to check out various wiring connections and would welcome any suggestions to help explain my recent experience.
Regards to All - George

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Take care - be aware



Replies:
Posted By: Brian UK
Date Posted: 16 Sep 2019 at 18:37
First thing to check is that the battery connections are clean and tight. If the lights went dim the battery was low. But when starting, turn the lights off anyway.

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Brian.

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


Posted By: c13pep
Date Posted: 16 Sep 2019 at 19:01
A 2 mile run would not be enough to recharge the battery following its initial start of the bike. Easiest to check is charge rate as my Monza doesn`t start to charge until 2000rpm,using a multimeter across the battery, if this checks out ok then as Brian says there must be a poor connection somewhere although if it were on the battery then I would expect this to result in a slow starter motor. Easiest to start at the alternator and work your way thro` to the rectifier and regulator. All 3 of my V50s have suffered with the problem of the original fuse box and the crap bullet fuses not making proper contact because of a build up of crud, but then again Guzzi electric are legendary for being poor

CHRIS

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you can`t have any fun in a straight line

Monza
Honda CB77 project



Posted By: BondEquipe
Date Posted: 16 Sep 2019 at 19:08
Originally posted by George George wrote:

Hello - I've had the first ride on the V50 mark 2 and it's quite a lot different from either my LE Velo or Honda CD175 . . .    
 

Blimey; you must be the first bloke in 40 years to get off any other bike and onto a V50 and think it's quick!!   Smile


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Stephen
Black & Gold LM2
+ Other Bikes & Projects!


Posted By: c13pep
Date Posted: 16 Sep 2019 at 19:24

Blimey; you must be the first bloke in 40 years to get off any other bike and onto a V50 and think it's quick!!   Smile
[/QUOTE]

You've not ridden an LE then

CHRIS

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you can`t have any fun in a straight line

Monza
Honda CB77 project



Posted By: George
Date Posted: 16 Sep 2019 at 19:35
Gents - thanks for the comments so far. Tomorrow I'll give the battery connections, earth etc a good coat of looking at and then take a look into the alternator charge rate. Is there anything specific to check out on the rectifier or regulator (I've not found them yet)?




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Take care - be aware


Posted By: c13pep
Date Posted: 16 Sep 2019 at 21:48
Usually behind side panels one on either side of tool box

CHRIS

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

Monza
Honda CB77 project



Posted By: Beekeeper
Date Posted: 17 Sep 2019 at 16:30
I don't know about other V50s but on our Monza the rectifier is just behind the headstock (remove the tank to check, wires exit to RHS.) and the regulator is situated behind the RHS side panel.

You sound like you're reasonably competent, but I'll post a link to the excellent Electrex trouble shooting guide anyway. I'm aware there will be minor differences as it refers to a single regulator rectifier unit but on the whole it's good advice!

https://www.electrexworld.co.uk/acatalog/Troubleshooting-3P-PMG-&-RR.pdf" rel="nofollow - https://www.electrexworld.co.uk/acatalog/Troubleshooting-3P-PMG-&-RR.pdf

You asked about weak points on V50s.....handlebar switches!!


Posted By: Mike H
Date Posted: 17 Sep 2019 at 19:56
Originally posted by George George wrote:

and it's quite a lot different from either my LE Velo or Honda CD175.


I expect so! LOL



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


Posted By: Brian UK
Date Posted: 17 Sep 2019 at 20:47
Originally posted by Mike H Mike H wrote:

Originally posted by George George wrote:

and it's quite a lot different from either my LE Velo or Honda CD175.


I expect so! LOL


I would hope so.


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

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


Posted By: Dennis menace
Date Posted: 18 Sep 2019 at 10:55
Mentioned on here before, it is worth running a dedicated, heavier gauge wire from the battery to the starter solenoid as the original set up is not great. I fitted a combined rectifier and regulator from Electrex World to replace the original parts designed by Frankenstein!
If your battery is good, it should turn over the engine for a good while. Might be worth trying another battery or jump leads to see if your battery is really that good. I bought a Motobatt AGM battery for a reasonable price and they work well.
Dennis


Posted By: c13pep
Date Posted: 18 Sep 2019 at 12:36
Originally posted by Dennis menace Dennis menace wrote:

Mentioned on here before, it is worth running a dedicated, heavier gauge wire from the battery to the starter solenoid as the original set up is not great. I fitted a combined rectifier and regulator from Electrex World to replace the original parts designed by Frankenstein!
If your battery is good, it should turn over the engine for a good while. Might be worth trying another battery or jump leads to see if your battery is really that good. I bought a Motobatt AGM battery for a reasonable price and they work well.
Dennis


The thing is whoever designed the original regulators and rectifiers couldn`t have been that bad as lots of them are still operating well, in my case some 39 years later.

CHRIS

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you can`t have any fun in a straight line

Monza
Honda CB77 project



Posted By: George
Date Posted: 19 Sep 2019 at 19:46
Hello and thanks again to all the comments / suggestions. I've checked the battery connection from neg to earth and the frame earth was not good so this has been sorted. The bike seems to be starting and the electrics working all OK.
I'm going to investigate the misfire tomorrow (the right hand cylinder and exhaust system run much hotter than the left after a relatively short run time). I have taken the carbs apart (having read Brian's earlier post) and all appears OK so I have a new coil to fit to the left hand side and I'll see if anything changes. Thanks again to all the posts and later tonight I must delve into the Electrex trouble shoot guide. I'll post any progress that I make.
p.s. had a run with the LE Velo club today - a lot of full throttle for much of the 74 miles and a heady speed of 45 noted (down hill slightly and we think the LE speedos do read a tad high). Best Regards - George

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Take care - be aware


Posted By: George
Date Posted: 20 Sep 2019 at 20:44
Just a quick update on the activity today. With the new left hand coil fitted the bike was easily started up running good on both pots. The revs at this time were around 1400 and I quickly checked the pipes / silencers and noted they were both increasing at around at the same rate. However after approx. 2 minutes of running the bike went onto to running again on only the right hand cylinder. I checked the plugs - both quite sooty. I swapped the plugs around and when it came to restart the battery couldn't crank the bike! Lights checked and seen to be dim, the horn wouldn't blow so CONCLESION 1 - the battery must be knackered even though it was pronounced in good health only the day before. A small 12 volt battery (9.1Ah (20 HR)/190 CCA) was hooked up to the system to test the lights, horn etc - all OK but I didn't attempt to start the bike on this battery. Instead I hooked up my Morris Minor battery and eventually I had the bike running to a state where I could adjust and attempt to tune the carbs. I found the carbs quite fiddly to set up (although I must admit playing with twin carbs is not my forte).I used vacuum gauges to achieve fairly good synchronisation and I'll have to give the bike a decent run but throughout this latest episode I noted that at all times the left hand cylinder / exhaust system was definitely lower that that of the right. I have two questions that somebody may be able to comment on 1) would different mixture strengths account for the temperature differences of the cylinders and 2)Although I am going to buy a new battery, would the battery with 190 CCA be able to cope in an emergency start situation. I was considering carrying this with me during the first runs until I get to know the bike is reliable / sorted. Best Regards - George


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Take care - be aware


Posted By: c13pep
Date Posted: 20 Sep 2019 at 21:19
Firstly all my V50s have suffered with sooty plugs unless they are given a good blast out on a decent run
The small battery should start the bike in an emergency but don`t expect it to keep churning the starter motor over
Mixture difference usually gives hot running on weak mixture and cooler running when too rich
Have you synchronised the throttle cables as part of the carb balancing ie. both slides opening at the same time
Have you done a compression test to ensure both cylinders are ok

CHRIS

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

Monza
Honda CB77 project



Posted By: redmunk
Date Posted: 21 Sep 2019 at 07:12
Check your valve clearances on the bad cylinder. If it’s too tight, a couple of minutes of running is enough heat to expand the pushrods so the valve no longer seats and it loses compression. 


Posted By: George
Date Posted: 21 Sep 2019 at 08:54
Hi and thanks To Chris and Redmunk for the latest replies. As best as possible I have set the throttle cables with the same amount of play although the angles of the cables into the carbs don't help with this op. I have done a compression test and both cylinders are equal within a pound at 100psi. I'm not sure what to expect on the compression test but would mention that the bike has done 55K - I have no idea of the maintenance history. Over this weekend I'll check the tappets and if I can buy a suitable battery, give the bike a more meaningful run. Best Regards - George.


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Take care - be aware


Posted By: c13pep
Date Posted: 21 Sep 2019 at 09:52
The compressions seem low but were the throttles wide open and was the engine hot.
My own V50s have usually recorded well above 150psi at cold and maybe dropping to not far short of this when hot, but two of them had been rebuilt.
Also as Redmunk has suggested these bikes rely heavily on correct valve clearances and the heads being retorqued after a few miles.

CHRIS

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

Monza
Honda CB77 project



Posted By: George
Date Posted: 21 Sep 2019 at 12:57
Hello Chris - when I did the compression test the engine was cold and the throttles shut. I get the feeling that in the not too distant future the top half of the engine is going to get a looking at. Thanks for the info and I've got another battery on order which should arrive mid next week. Best Regards - George.

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Take care - be aware


Posted By: c13pep
Date Posted: 21 Sep 2019 at 15:13
When throttles are open there should be a substantial increase in your compression figures which should be achieved within 3 - 5 rotations of the engine. The beauty of these engines is that the heads can be removed with engine in situ if valves need to be lapped in (another source of poor running and low compression)

CHRIS

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

Monza
Honda CB77 project



Posted By: George
Date Posted: 21 Sep 2019 at 19:02
Thanks for the info Chris - I'll do a compression test tomorrow with the throttles open. George.


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Take care - be aware


Posted By: Jerry atric
Date Posted: 21 Sep 2019 at 19:43
I think with the throttles open you will be relieved at the increased pressure you see


Posted By: Dennis menace
Date Posted: 21 Sep 2019 at 20:13


The thing is whoever designed the original regulators and rectifiers couldn`t have been that bad as lots of them are still operating well, in my case some 39 years later.

CHRIS [/QUOTE]

You are right of course but my original rectifier was shot when I bought the bike. By using the combined regulator /rectifier I found enough space for a larger battery
Dennis


Posted By: Brian UK
Date Posted: 21 Sep 2019 at 22:19
100psi with a cold engine and throttles shut is quite respectable I would say.
The more important thing is that they are both the same.


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

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


Posted By: George
Date Posted: 22 Sep 2019 at 11:01
Good morning to everybody - just a quick update on the compression check. With the engine cold and throttles open both cylinders were the same at 120 psi.
Best Regards - George.

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Take care - be aware


Posted By: Brian UK
Date Posted: 22 Sep 2019 at 12:31
That means there isn't a problem with compression. That figure would go up considerably when hot.

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Brian.

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


Posted By: Mike H
Date Posted: 22 Sep 2019 at 12:45
Re the battery, it won't charge at idling speed. Every start up will use more juice and it won't properly be replaced until actually ridden a few miles. Me I would contrive to use a battery charger in the interim and a power socket to plug it into is so much easier and more convenient than removing the battery to recharge  or using clamps. 




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


Posted By: c13pep
Date Posted: 22 Sep 2019 at 12:53
I think I have seen a calculation somewhere, possibly on here, that gives the psi rating for any given compression ratio
14.7 x bikes compression ratio = psi reading
Hence my Monza should read 152 ish psi
Can`t vouch for this but in my case it`s pretty accurate

CHRIS

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

Monza
Honda CB77 project



Posted By: Brian UK
Date Posted: 22 Sep 2019 at 13:19
That's certainly the ball park figure.



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

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


Posted By: George
Date Posted: 22 Sep 2019 at 13:51
Hi and thanks for the comments from which I feel that, although the compression may be down, it's really not too bad and is at least equal on each pot. I have checked the tappet clearances. The left hand cylinder figures were ok according to the manual - the right hand figures were a little up but these have now been adjusted. I will be investing in a battery conditioning unit and I'm going to take a look at a friends set up to see how he's laid it out. Regarding the battery that had been checked out earlier - the check can't have been very good as the battery when new was only rated at 280CCA (not the 399 as I was advised). Thanks for the input to date and best regards - George.

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Take care - be aware


Posted By: red leader one
Date Posted: 22 Sep 2019 at 16:32
http://www.halfords.com/workshop-tools/garage-equipment/battery-chargers-jump-starters?brand=Ctek&pageNo=1&pageSize=21&sort=we_recommend" rel="nofollow - https://www.halfords.com/workshop-tools/garage-equipment/battery-chargers-jump-starters?brand=Ctek&pageNo=1&pageSize=21&sort=we_recommend

http://www.optimate.co.uk/" rel="nofollow - https://www.optimate.co.uk/

Ya pays ya money and you know the rest.


Posted By: Brian UK
Date Posted: 22 Sep 2019 at 17:02
I believe the CTEK automatic charger is one of the best on the market. I have the 3.6 Amp one.

When it comes to batteries, the capacity in Amp Hours is the most important  part. The CCA figure must be adequate, but not so important.
All batteries lose capacity over time, so the more AH you start with the longer it will usually last.

Newer AGM batteries require a charge rate of at least 2 Amps, many battery conditioners won't supply this.


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

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


Posted By: George
Date Posted: 22 Sep 2019 at 21:29
Gents - thanks for the comments regarding the chargers. I will probably go for the CTEK equipment, my friend has one of these units which has given good service and was bought to replace his earlier OPTIMATE.
Best Regards - George.

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Take care - be aware


Posted By: Mike H
Date Posted: 25 Sep 2019 at 18:53
Thumbs Up





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


Posted By: George
Date Posted: 28 Sep 2019 at 16:20
Hello to All - I have another query this time regarding the carburettors on my V50 Guzzi. Having decided to fit new needles and atomisers I noted on the Dellorto parts drawing on the EUROCARB website that there are O rings and washers listed as fitments to the idling screw and slide adjusting screw. My manual however does not show or mention the O rings or washers and my machine does not have them fitted.
Best Regards - George    

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Take care - be aware


Posted By: c13pep
Date Posted: 28 Sep 2019 at 19:39
On the PHBH carbs (V50/3) the o ring sometimes gets left behind in the hole when the idle screw is removed. However V50/2 runs different carbs so not sure whether they are similar to the PHBHs, if they are fitted then they are important as they seal the adjusters and keep them air tight.

CHRIS

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you can`t have any fun in a straight line

Monza
Honda CB77 project



Posted By: George
Date Posted: 28 Sep 2019 at 20:44
Hi Chris - thanks for the reply. I have a looked into an exploded diagram of the carbs and I think that the diagram of Eurocarb is not actually the VHB fitted to the Mark 2 (as you eluded to). From the parts diagrams that GUTSIBITS have sent me the carbs fitted to the Mark2 do not have the O rings and washers at the idle and slide screws. Thanks again - George.

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Take care - be aware



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