Bigleo, I'm assuming you've got the jim-dandy chain rivet-brad tool made by MotionPro, or similar. Worth double the price, IMO.
With the endless chain, simply dremel hone two of the chain pin ends of their bradded-ness, where you can tell they'll push through "easier" without messin' up the rollers. Works slick. If you scar up the plate, you're not using that part anyhow; replacing with the rivet-master-link.
RE; vacuum advance~~"two" (the 'proper' 2) manifold vacuum sources might be enuf to do, what you're drivin' at, to get a co-ordinated "pull". All four, might make it "full on" all the time. Would need pilot jets in the lines, of course, whether you did 2 or did 4.
Also, when Yamaha was making all these "yearly" changes, no doubt, they were willing to make power band "sacrifices" to deal with EPA. And, if I'm not mistakin', I think we had higher octane fuel(s) then. You would time different for that.
With the endless chain, simply dremel hone two of the chain pin ends of their bradded-ness, where you can tell they'll push through "easier" without messin' up the rollers. Works slick. If you scar up the plate, you're not using that part anyhow; replacing with the rivet-master-link.
RE; vacuum advance~~"two" (the 'proper' 2) manifold vacuum sources might be enuf to do, what you're drivin' at, to get a co-ordinated "pull". All four, might make it "full on" all the time. Would need pilot jets in the lines, of course, whether you did 2 or did 4.
Also, when Yamaha was making all these "yearly" changes, no doubt, they were willing to make power band "sacrifices" to deal with EPA. And, if I'm not mistakin', I think we had higher octane fuel(s) then. You would time different for that.
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