Author Topic: Flopp automatic advance unit  (Read 1288 times)

Offline iansoady

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Flopp automatic advance unit
« on: 18.08. 2010 15:35 »
Another minor issue raises its head. Whilst I have the timing cover off, I twiddled the automatic advance unit (asyou do). The pins that the weights pivot on and have the springs attached seem loose in the backplate - to such an extent that the springs don't seem to return the unit to full retard. If I rotate the mag (via the engine) it does return to full retard but it looks as though the timing is going to be wildly erratic when running.

I take it that this isn't normal - I have no experience with these devices as all the mags I've previously had have been manual advance.

I was wondering whether these units are dismantleable(?) and if anyone has any experience of doing this. Being a cheapskate I don't want to shell out for a new unit unless I really have to. I was wondering about MIG welding the pins to the backplate......
Ian.
1962 Golden Flash (arrived)
1955 Velo Viper/Venom (departed)
2004 Triumph Tiger 955i (staying)

Offline BSALarry

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Re: Flopp automatic advance unit
« Reply #1 on: 18.08. 2010 19:38 »
Hello - I have just gone through the process of rebuild of magneto and automatic timing gear. I to did not want to spend excess money on the timing gear after shelling out for rebuild of magneto. My problem was about 8 or 9 missing teeth on fibre gear. So, I purchased a new fibre gear and thought how hard could it be. How wrong I was. I found that the rivets that are required to rebuild the timing gear are hard to come by. I ended up asking about 20 or so shops/people at kempton park bikejumble and they all indicated one chap who is expert in the rebuild of the timing gear. I sent it to him and it cost 81 pounds to rebuild. I must say he did an outstanding job and it looks brand new. When I put it all together the bike started at second kick...so me thinks the automatic timing gear (and magneto) are one of those areas that you need to spend the money on...unless you have a milling machine/lathe in your garage.

Online Triton Thrasher

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Re: Flopp automatic advance unit
« Reply #2 on: 18.08. 2010 23:02 »
the springs don't seem to return the unit to full retard. If I rotate the mag (via the engine) it does return to full retard but it looks as though the timing is going to be wildly erratic when running.
...

Before you do anything rash- did you have a running problem?

At idling rpm, the friction of the cam on the points heel drags it back to full retard.  At normal running speed, it's at full advance.

Offline wilko

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Re: Flopp automatic advance unit
« Reply #3 on: 19.08. 2010 09:38 »
On different forums it seems it's the oddball rivets that you can't get, so this is where a lathe comes into it!

Online lawnmowerman

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Re: Flopp automatic advance unit
« Reply #4 on: 19.08. 2010 11:05 »
 Stu55flash has just mentioned in a recent post that he had to buy a bag of 100 of these rivets for the A/R gear and only needed four. He has kindly offered to let other members have some so may be worth contacting him if you need some.

Jim
1959 A10 SR
1938 Wolseley 14/60
1955 Ferguson TEF20 tractor
1965 Ferguson 135 tractor
1952 Matchless G80 rigid
1960 BMW R60
1954 Matchless G80S
1955 Ariel 500 VH
1951 Sunbeam S7DL
1960 Matchless G12 with Watsonian Monza
......and loads of lawnmowers

Too old to Rock and Roll but too young to die  (Jethro Tull 1976)

Offline iansoady

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Re: Flopp automatic advance unit
« Reply #5 on: 19.08. 2010 12:31 »
Stu55flash has just mentioned in a recent post that he had to buy a bag of 100 of these rivets for the A/R gear and only needed four. He has kindly offered to let other members have some so may be worth contacting him if you need some.

Jim

Indeed and I'm in the process of contacting him.
Ian.
1962 Golden Flash (arrived)
1955 Velo Viper/Venom (departed)
2004 Triumph Tiger 955i (staying)

Online Triton Thrasher

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Re: Flopp automatic advance unit
« Reply #6 on: 19.08. 2010 12:50 »
A rivet being only a piece of mild steel dowel, lack thereof shouldn't hold you up for too long.

Offline a101960

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Re: Flopp automatic advance unit
« Reply #7 on: 19.08. 2010 16:55 »
This page might be of interest to anyone that is thinking of overhauling a k2 auto advance unit
http://homepage.ntlworld.com/david.gibbison/v-tec/Files/Lucas%20ATDs.pdf