Advance/retard VB600

Singles, twins and fours.
MarkOgden
Posts: 79
Joined: Mon Sep 05, 2016 9:12 pm
Contact:

Advance/retard VB600

Postby MarkOgden » Sat May 08, 2021 4:49 pm

Greetings all after a long absence - prompted by work, restoration of other bikes and the rotten weather!

Couple of questions if I may

After a little fiddling after a long lay up, the VB600 fired up fine enough. I think I have established that I have a tight wire advance - that is to say looking at the right hand side/nearside of the bike, the mag take off is on the right, and pulling the wire tight turns the baseplate ACW. Do please correct me if I am wrong here!

Assuming then tight wire advance, bike seems start best at just a little off full retard - cable essentially slack, but following instructions and knowledge of other bikes - when it is warm, I set to full advance - lever fully forward and wire tight. When warm and at idle however, this seems to cause poor running or stall the bike - though granted I have not ridden it just yet at full adavnce. Question then - is this normal? I always thought that when warm you set it to full advance and basically leave it there, but as stated, at idle anyways, it does not seem to like full advance.....perhaps not warm enough?

Second Q - it does not appear to be charging when revved - i.e. ammeter does not move to right. Ammeter/circuit does work, as when the lights are on it moves to the left. Pretty sure it was charging fine last time. Weak battery perhaps? I have not removed the battery and charged it and I know regulators do like a fully charged battery. 12V, + earth by the by.....

Many thanks

Mark

roger.fellows
Holder of a Silver Anorak
Holder of a Silver Anorak
Posts: 824
Joined: Tue Feb 21, 2012 8:32 pm
Location: S.Cumbria UK
Contact:

Re: Advance/retard VB600

Postby roger.fellows » Sat May 08, 2021 5:04 pm

The right hand side is the off-side, Mark.

Near side - near the kerb.

MarkOgden
Posts: 79
Joined: Mon Sep 05, 2016 9:12 pm
Contact:

Re: Advance/retard VB600

Postby MarkOgden » Sat May 08, 2021 5:17 pm

Roger

Depends if you are looking from the front or the rear of the bike! :) but quite right - I am a fool. Definitely looking at the left side/nearside!

Cheers for that

Mark

User avatar
alan.moore
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 1432
Joined: Sat Jul 19, 2014 1:29 pm
Location: Leicestershire UK
Contact:

Re: Advance/retard VB600

Postby alan.moore » Sat May 08, 2021 6:06 pm

Re not charging I'd first suggest cleaning the dynamo commuter with some petrol on a rag and make sure its clean and bright. After being layed up for a while I've found mine sometimes fail to charge. A quick clean sorts it out.

Could also so a case of the dynamo loosing its residual magnetism so it will need flashing. Info on how to do that and all things dynamo here viewtopic.php?f=8&t=189

Re Mag...yes with cable takeoff on right of mag tightening cable moves baseplate anti-clock which is advancing it.

I've found on mine (VH and W/NG) It will idle better on half retard, as advancing it fully makes it tickover too fast... but advancing it does not make it want to stall.
Cheers
Alan
1939 VH Redhunter;1942 RN WNG;1951 Triumph 6T Thunderbird;1970 BSA B175 Bantam;1986 Yamaha SRX600 single
http://cloggymoore.wix.com/triumph-pre-unit-6t

User avatar
simon.holyfield
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 4122
Joined: Mon Oct 17, 2011 11:16 pm
Location: Norfolk
Contact:

Re: Advance/retard VB600

Postby simon.holyfield » Sat May 08, 2021 6:14 pm

alan.moore wrote:I've found on mine (VH and W/NG) It will idle better on half retard, as advancing it fully makes it tickover too fast... but advancing it does not make it want to stall.
Cheers
Alan


My W/NG behaves in exactly the same way.

When you set up the timing, you did it on full advance with the correct point gap?
cheers

Simes

'51 Square Four,
'58 Huntmaster,
'42 W/NG,
'30 Model A
https://ariel-square-four.blogspot.com

User avatar
alan.moore
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 1432
Joined: Sat Jul 19, 2014 1:29 pm
Location: Leicestershire UK
Contact:

Re: Advance/retard VB600

Postby alan.moore » Sat May 08, 2021 6:18 pm

Simes
Is that Q for Mark?
1939 VH Redhunter;1942 RN WNG;1951 Triumph 6T Thunderbird;1970 BSA B175 Bantam;1986 Yamaha SRX600 single
http://cloggymoore.wix.com/triumph-pre-unit-6t

User avatar
simon.holyfield
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 4122
Joined: Mon Oct 17, 2011 11:16 pm
Location: Norfolk
Contact:

Re: Advance/retard VB600

Postby simon.holyfield » Sat May 08, 2021 6:22 pm

alan.moore wrote:Simes
Is that Q for Mark?


Yes, sorry!
cheers

Simes

'51 Square Four,
'58 Huntmaster,
'42 W/NG,
'30 Model A
https://ariel-square-four.blogspot.com

MarkOgden
Posts: 79
Joined: Mon Sep 05, 2016 9:12 pm
Contact:

Re: Advance/retard VB600

Postby MarkOgden » Sat May 08, 2021 9:05 pm

Alan

Thanks for tip on the commutator - I'll give it a whirl - so to speak. Battery also on charge. It was reading 12.9 volts.

I would concur that full advance should increase the revs at idle. Not so here

Timing - completly forgotton how I did it to be honest, but worth a check. Is there a basic procedure?

bevanclark
Holder of a Nylon Anorak
Holder of a Nylon Anorak
Posts: 196
Joined: Fri Jun 08, 2018 3:58 am
Location: Methven, New Zealand
Contact:

Re: Advance/retard VB600

Postby bevanclark » Sat May 08, 2021 9:29 pm

Mark,
Your description of poor idling when you go to full advance does not sound normal. I set my bike to full advance pretty much straight away and don't touch it again, unless I'm trying to show off with how slow it will idle :)

I'd check your points & gap, then the timing which is supposed to be 1/4" before TDC on max advance. You'll find that some of the experts on this forum have suggested that the combustion characteristics are better if the timing is further advanced than that. I wonder if you have some carb issues - how worn is it ?
I found that my magdyno will not charge a flat battery. Once I'd charged it up a bit off the bike, charging worked fine.

Cheers, Bevan

User avatar
simon.holyfield
Holder of a Golden Anorak
Holder of a Golden Anorak
Posts: 4122
Joined: Mon Oct 17, 2011 11:16 pm
Location: Norfolk
Contact:

Re: Advance/retard VB600

Postby simon.holyfield » Sat May 08, 2021 10:34 pm

MarkOgden wrote:Timing - completely forgotten how I did it to be honest, but worth a check. Is there a basic procedure?


I wrote this a while ago:

http://ariel-square-four.blogspot.com/2 ... s.html?m=0
cheers

Simes

'51 Square Four,
'58 Huntmaster,
'42 W/NG,
'30 Model A
https://ariel-square-four.blogspot.com


Return to “Four stroke”

Who is online

Users browsing this forum: No registered users and 12 guests