Left Cylinder Timing

[minnesota750]

Hi Everyone,
I've reached the point with my TX that I'm Confident my jetting and the rest of the other possible anomalies are correct and are not contributing to my current issue. I'm having some issues with the timing for the left cylinder. I time the right using the light, then go to time the left, but am having trouble getting it dialed in. It's advanced almost to the 37 degree mark, and I can't seem to dial it back farther than just before the last "F" mark before the 37 degree mark, or just on the mark, definitely not between the two as the manual states.. Not sure if I'm missing something or if my point gap is off and that's causing the poor timing. I'm not experienced enough with the points ignition system to troubleshoot it. Any advice, tips, tricks from those in the know would be awesome.
TxRp.

[bigskyforever]

When you check your points measure the max. opening of the points. If the gap is too large the contact points will open way too early. I suspect this is your issue. Go back to the right cylinder and recheck the max. opening and readjust if required and then go back and readjust the left cylinder. There is a mark on the cam which indicates the point of max. opening of the contact points.

[bigskyforever]

I have taken for granted that you know about the adjustable contact plate for the left had points needs to be moved.

[minnesota750]

Hi,
Thanks for the response. Yes, I adjust the right side first and then the left. I ordered a dwell meter to test the dwell. I think this will help as I'm not very good at setting the points. It took quite a lot to get it to the state it is now - gap that is. I also ordered new springs for the advance mechanism and will replace those to make sure everything is kosher. I had a feeling that my point gap was too large based on symptoms, so it's good your advice was in line with my suspicions. If I can't get things times I might just invest in an electronic advance. Thoughts on switching over?
TxRp.

[retromech]

In my humble opinion although I understand why people like points and like to retain them I for one am a great fan of electronic ignition (even one that does not eliminate the mechanical advance),having spent many hours as a professional mechanic setting points and dealing with the issues points systems can produce I am always keen, particuarly on multi points systems to do away with them and fit an electronic system. I have done this on my TX and it is a much better bike for it, biggest problem with a TX is what system to fit as most are expensive, mine is a home brewed system based on a Lumenition car system which uses an optical sensor which is not considered desirable by many, therefore in the future I may make a system using a different triggering system.

[minnesota750]

I bought the Elektronik Sachse electronic ignition - works like a dream. On a related note, does anyone have the bulletin that mentions slightly retarding the ignition timing? Ive seen it referenced but havent been able to find anything from Yamaha about it.

After I got my electronic ignition I found my valves need to be adjusted, i have blowby on the right cylinder I had been attributing to carbs. Process of elimination I guess.

[bigskyforever]

Set the right hand cylinder at .015th and then set the left hand cylinder at the same clearance. This will allow you to get the cylinder to fire where it needs to be at approx. 6 degrees btdc.

[minnesota750]

Interesting. By setting the valve clearance tighter it acheives the same effect as retarding the timing?