GS550 / 673cc which timing plate between GS550 and GS 850??

[boris.h]

Hi evarybody

For my gs 550 / 673 swap, I still have my brand new gs 550 timing plate, and an other one, a gs 850 one.

1) is it possible to put the gs 550 plate? the gs 850 plate?

2) in case of yes, I presume that there is one of them that have more advance... In that case I can try with the plate which can make more advance... what is your advice?

thanks!
Boris

[tkent02]

Advance doesn't really matter, the only time it will be below the full advance RPM is when it is idling and timing won't matter much.
Set the full advanced timing where you want it and be happy.

[boris.h]

Yep but I assume there is a mechanicall advance mechanism which has two values, one for idling and around and one max value... is the 850 better than the 550? Moreover the 550 plate is with points and the other is electronical (the 850 one), with hall sensors... which one is the best to put on? Thanks

[boris.h]

ok, soooo could someone help me with advices in my choice? thanks a lot

[tkent02]

Do you want points or do you want electronic? Do you have everything you need to do the electronic?

[tom203]

I'd use the plate that "mates" with ignitor that you intend to use. The advancer is progressive- it advances from idle spot to full by about 3500 rpm .

[tkent02]

That's exactly my point, any normal riding RPM it's fully advanced, where it is at idle doesn't matter much as long as it idles. Going with the standard 550 points ignition on mine, because that's whats on there and it works fine. I'll let you know how it runs tonight if I get the carbs together.

[boris.h]

yep, thanks a lot!
I thought there was a different "full advance" value between the 850 plate and the 550 plate....
Ok, so I'll start with the 550 plate with points, the plate is brand new so I'll void issue using it.

[tkent02]

yep, thanks a lot!
I thought there was a different "full advance" value between the 850 plate and the 550 plate....
Ok, so I'll start with the 550 plate with points, the plate is brand new so I'll void issue using it.

The points type plate you can put wherever you want it, the 850 one you would have to slot the holes to move it.