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Timing problems

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UKROBK7:
I am having problems getting the 2-3 points on the 750 to adjust.  They need to move anti-clockwise (about 10-15 degrees) further than the adjustment allows so obviously something is wrong.  Points 1-4 set up OK.  The points plate is new so I thought it would be a quick install but I have been at this for ages!!  Everything looks OK, I am now wondering if someone replaced the advance/retard mech' as the locating pin is a little small for the crankshaft hole and does not give a positive fit - is there any way of identifying the correct one?.

Before I stripped the bike I found the old plate had the 2-3 points on full anticlockwise adjustment as well.

Any ideas?

Bitsa (Ralph Wright - RIP):
Rob.The correct advancer should have 300 stamped on it.I have tried to fit aftermarket plate points etc and ended up fitting Honda parts and guess what they worked no problems,
Hope this helps
Bitsa

UKROBK7:
Thanks Bitsa, mine is stamped 300 so thats OK.  I bought a pattern points setup as I was going to change to electronic ignition after I get the engine running correctly (engine and carbs fully rebuilt and waiting to go into frame) and didn't want to spend too much money.  Silvers say they have never had problems with these.

I am going to have another go this morning and see what happens, I think the fibre/plastic part of the pattern points has been moulded too short.

Rob

Waggles:
Firstly, pattern points have been known to cause problems like this, seems a shame to get some if you are going for and electro set up, might save some of your hair though ......

Other things that can cause this problem are badly fitting back plate, check gap between edge of plate and the casting where the attachment screws are, this should be no more than 0.1mm according to 'Hondaman', too much slack means the points spring force can move the whole plate down and retard ignition. You can get round this by putting a shim in the bottom gaps while you adjust, then remove once plate tightened. Finally, is your shaft bent? this can happen if you use the points cam nut to turn the motor anti clockwise ( or other less than gentle practises  ::) )

Bitsa (Ralph Wright - RIP):
Waggles is right the pattern points plate wobbles around like a dick in a wellington boot.Ditch it for a genuine one albeit s/hand.As it wobbles it naffs up the points gap.
Best of Luck
Bitsa

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