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Ossa Tr77 Points Gap And Btdc Setting

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Hi all

I'm restoring a TR77 that I was given as a box of bits (and so have no knowledge of set up...). My Clymer manual tells me that the Ossa has electronic ignition, although the points and condensor set-up on my bike suggest otherwise!

 

I've fitted new points and condensor and now need to set the points gap and timing. The back plate has a clear timing mark that lines up with the crankcasings, so I set it at this position. I then set the points gap to 15 thou, and this opened the points at around 2.2mm BTDC. I searched the internet and found suggestions of anywhere between 2 and 3.5mm BTDC, and a points gap of 40 thou seemed a common theme.

 

 

So, what works best, or what is a good starting point for both the points gap and the BTDC setting?

 

Also, I have no idea which wire goes where! The Alternator/timing coils unit behind the flywheel has 4 wires coming out - Black, Green, Yellow, and a pale pink colour. Any info on which one does what would be welcome. I'm hoping to run a brake light and horn, without a battery - if anyone has done this, your advice welcome. :-)

 

Thanks for your help

Adrian

 

 

 

Timing is personal choice but yes, somewhere between 2 and 3.5 BTDC is the range most commonly used

 

Can't help with points gap or wiring as never had a points ignition Ossa

 

All MARs were fitted with electronic as were Grippers. For whatever reason the TR77 was fitted with points although a few may have had electronic. The MAR or Gripper electronic system will fit straight onto a TR77 as the engines are all the same.

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