350 nh

[Petebarn]

Hi all looking for some guidance 57 nh it's back firing through the exhaust and carb I've checked the timing as best I can and at tdc the points are fully open and are at the bottom of mag when open,any help will be gratefully accepted. Pete

[adrie.degraaff]

A worn carb. or inlet guide?

[dave.owen]

Points should be just opening at tdc with both valve closed and ignition fully restarted.

Check for air leaks on exhaust

Dave

[Petebarn]

Thanks something for me to try ,I'll have to get a puller cause points are fully open at tdc

[Petebarn]

I might add bike does not run I've rebuilt carb and got good spark.

[Steven.Carter]

Whereabouts are you, there could be somebody close by that could help you.

Steve

[Petebarn]

Steve I'm just passed Swansea bit out of the way but if any one out there is close I'd welcome there help ,first Ariel I've owned so not got any knowledge of them.Pete

[ian.scott]

Thanks something for me to try ,I'll have to get a puller cause points are fully open at tdc

You dont need a puller to get the points off to change the timing.

Ian

[dave.owen]

You will need a puller for the mag sprocket, try drags or John budgen

[Simon.Gardiner]

Points will be fully open at TDC if it's fully advanced on the lever, but if you push (or pull) the advance/retard lever fully retarded do the points then close (or get very close to closing)? (See earlier advice from Dave Owen on timing on full retard...)
-make sure you're advancing and retarding the correct way, there are different combinations of magneto and lever, it could be working the 'wrong' way;
-also be aware that the points carrier can get a bit sloppy on the end of the magneto ie it can be twisted forwards/backwards under firm (but not excessively forceful) pressure; this isn't a fatal problem in itself but it's possible to inadvertently move the timing when playing with the points (if you've got this it's best to time with the carrier pushed 'back' fully so you know where it's supposed to be).

HTH

SG