750 SF Electronic Ignition

Are you sure the choke plungers are properly seated, with play in the cables with the tank on etc. How many turns out are the idle mixture screws when it idles well; it should be about 1 1/2. If it is one turn or less fit smaller pilot jets. Normal size is 45 from memory. As you have replaced the needle jets and needles it rules them out, and your main jets only affect 3/4 to full throttle.
As pointed out, the problem is there even when the points are correctly adjusted, so isn?t likely to go away by replacing them with electronics.
What is the condition of the engine, compression, camchain stretch etc? What exhaust system is on it?
 
Tippie said:
Are you sure the choke plungers are properly seated, with play in the cables with the tank on etc. How many turns out are the idle mixture screws when it idles well; it should be about 1 1/2. If it is one turn or less fit smaller pilot jets. Normal size is 45 from memory. As you have replaced the needle jets and needles it rules them out, and your main jets only affect 3/4 to full throttle.
As pointed out, the problem is there even when the points are correctly adjusted, so isn?t likely to go away by replacing them with electronics.
What is the condition of the engine, compression, camchain stretch etc? What exhaust system is on it?
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Thanks for the comments. Yes will do a thorough check on the carburettor settings, and as you say will double check the pilots.
 
Also check float heights,came across this myself only recently,makes a big difference,see my posting on float heights,also check that the small rubber on the  idle mixture screws has not been forced into the body of the carb,have come across this in the past,bent piece of Mig wire will pull it out, iam sure most people will say find the flault first then move on if you want to,find the fault and save your money :D :D :D :D :D :D :D :D :D :D :D :D :D
 
VW Points come with the Pole mounted to the Points mounting Plate. It's seems to be common practice to remove the Pole which locates the Points from the Bikes Distributor Plate then mount the VW Points. I've also had success with removing the Pole from the VW Points and drill the hole slightly larger to slide them over the Bikes Distributor Plate Pole.

I'm with Paul - Points have been very dependable for me although I do carry a spare and condenser but have yet to use it. However; I'm looking into that "Electronic Ignition Module Electronic Kit K2543" - It looks very interesting.

One thing I've noted about most electronic ignitions is that they will not permit the engine to tick over much below 800 rpm.
 
K2543 is the Vellerman transistor assisted ignition, also sold by Maplin? I've considered this too BUT you'll need two kits for a twin with independant contact breakers. The kit is intended for a vehicle with a distributor. With the required transistor heatsinks the installation will be quite bulky. That's why I suggested the Hondaman TAI.

Cheers

Steve in UK
 
OK - I got it now the Hondaman TAI is differnet from the Vellerman K2543 Kit - Can you give us a link for the Hondaman TAI Kit ;o)

I don't think North Americans have access to Maplin unless we order overseas from the UK.
 
As I say, you'll be using the existing mechanical auto advance so be sure it is working properly. If you do it, it will be interesting to see how the TAI performs.

Cheers, Steve
 
I had that same problem with my 1970 750SF. It would foul plugs very quickly. Turned out to be the cables for the enricheners. The cables would pop out of their sleeves in the junction box under the tank due to excessive play. As mentioned above, I would carefully check that your enrichening plungers are fully closed.
 
merlin said:
I have a 1974 SF2 and have fitted a pazon ignition it was for a triumph same advance curve I read about the conversion in real classic magazine you can read it online ,works well
dave
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Thinking of fitting Electronic ignition and wondered how your Pazon system worked out?
ATB
 
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