Question on a Stock Trigger Wheel

[Tx Bohemian]

Is a stock trigger wheel set to 0* TDC or is there some advance built in?


I see in the manual there is a way to check timing through the little round cover on the belt housing but no way to adjust it except to change the TW or ECM.

I’m going to do the .030 filing on the stock TW to get 4* advance but I’d like to double check it also seeing as my machining may not be the most accurate.

If the stock TW is set at 0* I can check and mark it then, using Blackducks idea, use a timing light with a “Dial back” feature after the filing “modification” to check to make sure it is at 4* and maybe “fine tune” it if needed.

[Ricky-D]

Yeah, I think the stock wheel is at 0 degrees.

And the advance is controlled by the ICM.

Since the stocker is at zero, when you alter that to some other value 4 degrees or whatever, then that becomes the baseline (assumed zero) your ICM observes.

***

[Tx Bohemian]

Thanks Rick.

I did have an aftermarket 6* and I liked the way it ran, but it was causing a cold start issue (wouldn't start if the ambient temp was below 50).  That's fixed with the stock TW but now my mileage sux.

With the info here I'm attempting to go to 4* and with my I/S ECM that should do me good.

[Bigwolf]

No, the stock trigger wheel is not at 0* TDC.  I do not remember exactly but I believe it is 3 & 1/2* advance from TDC.  That means that a 6* advance aftermarket trigger wheel would be actually 9 & 1/2* advance from TDC.
Be careful if you use a timing light with a dial in advance setting.  Most of those are expecting just one firing of the sparkplug per cycle but the Valk fires twice per cycle.  This will cause your readings to be wrong.

[Patrick]

Bigwolf is correct. The factory base timing is appr 3º. I checked it years ago when this trigger wheel 'thing' was new. Just a suggestion, personally I would limit your filing to about .020" especially if you live in a cooler climate.

[98valk]

pg 17-2 of service manual

ignition timing "F" mark - 3.5 degrees BTDC @ idle

[Tx Bohemian]

Bigwolf is correct. The factory base timing is appr 3º. I checked it years ago when this trigger wheel 'thing' was new. Just a suggestion, personally I would limit your filing to about .020" especially if you live in a cooler climate.

OOPS!!!
Just this morning had a buddy in our machine shop file it down .030.
As I see it I can always rotate it back a tad if it's too much.

I live in S. Texas and, yeah, it gets down to a bone chillin' 40* at times during the winter (that's 20* too cold for me)!!!

Little side note:
When I pulled this TW off last night I noticed a bit of slack/play between the crankshaft slot and the TW tab. And the TW was as far back (retarded) as it could be. Not that much difference, maybe a degree I'd assume.
Before I disassembled I checked the timing so when I go back I'll see how much of an advance this is.

[97Valk_CT_Euless]

When I was doin mine a few weeks ago I noticed the same slack in the stock key. I looked at the cam sprockets and they have a slightly lower amount but still noticeable amount. I estimated about 1 deg total on the trigger wheel (+/- 1/2 deg) with slightly less than that on the cam and crank sprockets. Just tried to keep the sprockets centered and the trigger wheel at 4 deg. Made me wondered if pushing them as far advanced as possible when buttoning it up might gain alittle performance or hurt it. Obviously wouldn't move far enough to interfere.

[Tx Bohemian]

Well, got this "modified" TW on last night and fired it up.

Grabbed the timing light to check the advance,  HOLY COW!!!  This thing looks to be about 20* advanced!!!   WTH!!!





Then I remembered: it's a nippy 55* outside and the choke is on so it's at fast idle.
Once it warmed up and the choke was off the timing was where it should be, I think.

Someone marked the "indicator plate" (the plate with the 1-2, 3-4, 5-6 on it), I take it, where the timing is for the 6* TW. Which is about, and I'm guessing here, 1/4" above the "1-2" mark.
Before I took the stock TW off I checked the timing and it was right at the "1-2" mark.
Now the timing is right below the 6* mark.  I was shooting for 4* and I'm quite confident this is where it's at.  I couldn't locate a "dial back" timing light so I had to do it the "bohemian" way and give it a best guess.

I didn't get to ride it, as I said it was tooo cold!! (55*)
Actually it was about 10 by the time I got through and 4:30am alarm comes too soon!!
I'll have to try it this w/e.

Thanks for all the help, information, and suggestions guys.

[Farther]

I didn't get to ride it, as I said it was tooo cold!! (55*)

You can't keep me off the bike when it gets that warm!