using a timing light

[STVR]

Hello I have never used a timing light but correct me if I
Am wrong here. Connect light to battery connect right plug
Wire to light. Start engine point gun at timing mark on
Rotor should be in between the 2 F marks. Move plate
Forward to advance or counter clock wise to retard. Go to left side hook up light connect to left plug and repeat moving the left side of backing plate to adjust timing. Do I have this right?

 

[GreasyC]

Sounds like you got it. Although they never seem to mention it in the manual it's the timing at full advance that's important, not the idle timing. You spend most your time actually riding, not sitting still idling, so most of the time that the engine is under load and doing it's thing it's at full advance. It's important to check both conditions to make sure your advance unit is operating right. Also be aware that the point gap affects the timing. A wider gap advances the timing, narrower retards it, so if your gaps aren't right you can run out of adjustment on the timing plate before you get it right and end up very confused.

 

[CDNTX650]

also, as advance weights wear, your advance will swing wide, you can dial back full advance to where it's supposed to be but then your idle timing will be so retarded it will be hard to start and have a big flat spot.

I set mine proper at full advance (this is still with a brand new advance unit keep in mind and it was still advancing to much) then use a small dab of jb weld on the advance weight stops to keep it from retarding to far and keep it in the range its supposed to be. takes some effing around and some filing of the jb if you put to much on...But its right where it should be now.

 

[650Skull]

also, as advance weights wear, your advance will swing wide, you can dial back full advance to where it's supposed to be but then your idle timing will be so retarded it will be hard to start and have a big flat spot.

I set mine proper at full advance (this is still with a brand new advance unit keep in mind and it was still advancing to much) then use a small dab of jb weld on the advance weight stops to keep it from retarding to far and keep it in the range its supposed to be. takes some effing around and some filing of the jb if you put to much on...But its right where it should be now.

RG, (I think come up with the idea), 5twins and a few others have preened the heel of the advance weight so it will sit snug in the advance rod, (minimal play not sticking), one of them posted a pic showing how it is done, its a very simple solution and wont add weight to the weights. RG said he got the idea from grizld1


Here is the tread detailing the procedure.

 

[CDNTX650]

I have heard of peening them, but the very little it took shouldnt add enough weight to make a difference. Bike still advances where it should according to tach and light. Its hardly noticeable on the weight stops.

 

[STVR]

so as it turns out just had to really focus on my points gap got the timing down. Bike seems to run good a minor oil leak on the top end near the right exhaust neutral is hard to find but I will sort that out. No better feeling than ripping your motor apart rebuilding and then riding it. Thanks to eveyone that helped me along the way!

 

[speez]

my full advance passes the mark for full advance what i'v read that's a no,no? i timed it with light to [F] as soon i give some gas it passes the mark i'm going to pinging, do i need to get the full adv. mark's dead on?

 

[GreasyC]

If I had to compromise on one end I'd make full advance perfect and let idle land where lands, but that shouldn't be necessary. With some improvising you can prevent the weights from swinging out so far. Welding/solder/glue are all fair game but don't try bending or hammering the stops, they're more fragile than they look.

 

[speez]

oops! i pinged them, well hamerd the crap out of them, before i read post, but it all went well i held the center piece and moved the weights they were a bit slopy so i pinged them until went in no more play and ATU moves nicely timed it my 2 marks are on the lines ( "F" and full) and wile i was there so i shortend my springs now i have a blue printed ATU or until,i read a nother thred should i see a diffrence in the bikes performance? or is it a better safe then sorry,thing?

 

[grizld1]

Thank you, Skull, for giving credit where it's due. GreasyC, you'll eventually learn (probably the hard way) that if you retard the idle timing too far to compensate for faulty bobweights, you'll wind up with carbs that pop out of the boots now and then at startup, and a nasty low-rpm flat spot as a bonus.

 

[GreasyC]

Wow, hehe no I won't be learning that the hard way luckily. Like I said, no reason to compromise either end, it's easy to make the weights stop where you want.