750 SF3 help required

N

nichbrin

New member
Location
South Staffs, Great Britain.
Just bought a 750 SF3 1978 ex Kuwait police bike from a nice elderly gentleman who can no longer drive/ride, according to the DVLA !!
The bike has covered 56000 Km, not run for 8 years and has no battery fitted.
I want to get the bike running, mot'd and onto the road, with a view to further refurbisment when i eventually retire.
I was told the bikes battery should be a positive earth, but looking at the (well used!!) Tim Parker bible supplied with the bike it shows negative earth connections only on the wiring diagrams.
I would appreciate any advice on my quest on getting the bike back on the road.
 
drikko said:
Definitely negative earth, time to stop listening to whoever told you otherwise :)

Where are you located?
Click to expand...
Thats a positive for negative earth ..............................definately time to stop listening to the "expert" who told you totherwise me thinks

UK would be my guess  :o

Location:
    South Staffs
 
The Kuwait police bikes would normally be fitted with an alternator. A Dynamo is used on other Breganze 750's - I'm not sure if the wiring for an alternator will be covered in the Tim Parker Green Book.
 
Normski said:
The Kuwait police bikes would normally be fitted with an alternator. A Dynamo is used on other Breganze 750's - I'm not sure if the wiring for an alternator will be covered in the Tim Parker Green Book.
Click to expand...

Not all of 'em. :D

Alternator wiring is not covered, but not much different to the dynamo.

piet
 
Thanks guys, it was the old owner who insisted it was a positive earth and also stated it had an alternator !!
which would be exactly the same as my slightly older Triumph Trident.
Any suggestions to which battery to use which will fit in without major stripping down in the battery tray area?
As the bike has done quite high mileage should the Primary and cam chains need replacing?
The square air filter is really perished, what type would be a good replacement?
It has Champion N2 spark plugs in at the moment but assume the replacements are N2C?
 
nichbrin said:
Thanks guys, it was the old owner who insisted it was a positive earth and also stated it had an alternator !!
which would be exactly the same as my slightly older Triumph Trident.
Any suggestions to which battery to use which will fit in without major stripping down in the battery tray area?
As the bike has done quite high mileage should the Primary and cam chains need replacing?
The square air filter is really perished, what type would be a good replacement?
It has Champion N2 spark plugs in at the moment but assume the replacements are N2C?
Click to expand...


SF engine (36mm carbs) would require the N2/C/G plugs.

Always a good idea to replace the primary chain if age/mileage is unknown.  Timing chain replacement can usually wait till the engine is overhauled.  Quite some hassle to replace, engine needs to be removed.

Filter element can be replaced with an auto item, the filter housing requires slight modification.  A 19Ah battery intended for Beemers is quite ample, fits in the battery box with room to spare.  I use an AGM type.

Photo of the front of the engine would be better. :D

piet
 
that's about right, most of them were stamped SF3 on the frame, but looked more like GTL's
they had a few triples as well !!!
CLEM
 
Thanks guys you've been a great help, but must admit I'm still not sure about this positive/negative earth thing, the guy who told me about it being a pos earth had owned the bike for 32 years and had several new batteries !! I'll let you know how it goes.
 
nichbrin said:
Thanks guys you've been a great help, but must admit I'm still not sure about this positive/negative earth thing, the guy who told me about it being a pos earth had owned the bike for 32 years and had several new batteries !! I'll let you know how it goes.
Click to expand...

If it has been re-wired, quite possible that it has a +tive earth.  A bit of charging equipment needs to be swapped, but the lights and plugs don't really care which direction the current flows.  Starter motor would spin backwards though. :D  Must have push-started for 32 years then...

piet
 
CLEMTOG said:
that's about right, most of them were stamped SF3 on the frame, but looked more like GTL's
they had a few triples as well !!!
CLEM
Click to expand...

The Kuwait Police Force had GTLs, SF3s and SF3s dressed up as GTLs (basically a GTL with an SF3 engine).  Many of these carried an alternator, but by no means all of them.  3Cs, 3CLs and 1200s made up the rest of the motorcycle fleet.  Apparently they used 750 Triumph Tigers before that, the desert sand probably played a bit of havoc with main bearings.  Laverdas were chosen specifically because they had roller cranks.

piet
 
sfcpiet said:
If it has been re-wired, quite possible that it has a +tive earth.  A bit of charging equipment needs to be swapped, but the lights and plugs don't really care which direction the current flows.  Starter motor would spin backwards though. :D  Must have push-started for 32 years then...

piet
Click to expand...
I've fitted a Nippon Denso alternator from a Kwaka 1000 and it runs exactly as the original NEGATIVE EARTH SF genny did. I'd be astonished if your bike ran +ve earth.

Alternative to the squarish cartridge filter is to use two indiv filter pods, with the orig airbox cut down a little to make room (good ones, like Unifilter). Find some short tubes with the correct OD to fit firmly into the intake rubbers and you'll find airfilter pods that clamp neatly onto the stubs inside the airbox. Makes access very easy and can be removed and replaced in seconds.
 
nichbrin said:
Thanks guys, it was the old owner who insisted it was a positive earth and also stated it had an alternator !!
which would be exactly the same as my slightly older Triumph Trident.
Any suggestions to which battery to use which will fit in without major stripping down in the battery tray area?
As the bike has done quite high mileage should the Primary and cam chains need replacing?
The square air filter is really perished, what type would be a good replacement?
It has Champion N2 spark plugs in at the moment but assume the replacements are N2C?
Click to expand...

Any battery that will fit from 16AH up.
Paul
 
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