quick shotgun question

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ChiefP

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I performed my first shotgun last night and thanks to the outstanding how to, it went well. There a part in there where he says to be sure to keep an eye on the little rubber o-ring. One of mine blew out when I was hitting the idle mix screw hole with air. Took 30 minutes to find it. That's one you only do once... :bang head:

The brass plugs were still in so it's never been touched previously, but 2 of the idle screws were only in 1.5 turns? The other 2 were in 2.5. I put it back the way I found it, but thought that was strange. I started it, but didn't ride it so I'm not sure how well it responded (I've got a hanging idle). I know I should also sync the carbs and that's next on the to-do list.
 
Factory set them and lots times they are not all same amount of turns.

I had mine done once at a dealer with tail sniffer and was same thing,two cylinders at a diff setting....
Should run fine......
I'm back to even all around but that doesn't mean it's the bet setting
 
I performed my first shotgun last night and thanks to the outstanding how to, it went well. There a part in there where he says to be sure to keep an eye on the little rubber o-ring. One of mine blew out when I was hitting the idle mix screw hole with air. Took 30 minutes to find it. That's one you only do once... :bang head:

The brass plugs were still in so it's never been touched previously, but 2 of the idle screws were only in 1.5 turns? The other 2 were in 2.5. I put it back the way I found it, but thought that was strange. I started it, but didn't ride it so I'm not sure how well it responded (I've got a hanging idle). I know I should also sync the carbs and that's next on the to-do list.

1.5 is fine, if its tuned for it.
 
You can check the mix screws by ear to see if they are currently at the right place for your bike. Warm the bike. Synch & set the idle down around 900rpms. Begin with #1 and slowly turn it in until the bike stumbles. Back it out about 1/4 from there. If the bike dies doing this, just restart it and go on to the next cylinder. Do the same on all cylinders, while at the same time watching the synch guages for continued accuracy. Adj synch slightly as needed. After all four mix screws are set by ear/feel, and synch is still spot on, remove the synch guages. Reset idle up to 1000-1050 rpm. Rev the engine and test the throttle response. If it's a bit sluggish, you may try backing all four mix screws out another 1/8" or so and retest throttle response. This is how I set mine after any/all removal, or shotgun proceedure. It's way easier than attaching an exhuast gas sniffer and setting them per spec sheet, I think, (I have an exhaust gas analizer) and you prolly can't get them out of whack far enough to hurt fuel mileage much.
 
What they all said. Did the shootgun cure your problem?

I don't know yet. Seems to be idling smoother, but didn't get a chance to ride. Throttle response still seems slow to me and so does return to idle (but I don't have anything to compare to). I'll take it for a ride tonight. I ordered one of those sync guages on Ebay (the 4 vacumn guage ones), coming from the UK I think. I've read about other types but could find one. Building my own isn't for me.
 
You can check the mix screws by ear to see if they are currently at the right place for your bike. Warm the bike. Synch & set the idle down around 900rpms. Begin with #1 and slowly turn it in until the bike stumbles. Back it out about 1/4 from there. If the bike dies doing this, just restart it and go on to the next cylinder. Do the same on all cylinders, while at the same time watching the synch guages for continued accuracy. Adj synch slightly as needed. After all four mix screws are set by ear/feel, and synch is still spot on, remove the synch guages. Reset idle up to 1000-1050 rpm. Rev the engine and test the throttle response. If it's a bit sluggish, you may try backing all four mix screws out another 1/8" or so and retest throttle response. This is how I set mine after any/all removal, or shotgun proceedure. It's way easier than attaching an exhuast gas sniffer and setting them per spec sheet, I think, (I have an exhaust gas analizer) and you prolly can't get them out of whack far enough to hurt fuel mileage much.

Thanks, will give this a try once my guage gets here.
 
I bought one of the first generation 4 guage mercury types back in the 70's, and still make due with it to this day. I always worry about the mercury getting sucked out, but have managed to keep it all intact these past 30+ years. I even used it on my Gen II a while back to double check it's throttle plates. That bike's vacuum is a bit more than our Gen 1's, but the guages still got the job done. One of these days, I swear, I am going to break down and buy a newer set w/o the mercury hassle. I'll prolly go with a Motion Pro.
 
I bought one of the first generation 4 guage mercury types back in the 70's, and still make due with it to this day. I always worry about the mercury getting sucked out, but have managed to keep it all intact these past 30+ years. I even used it on my Gen II a while back to double check it's throttle plates. That bike's vacuum is a bit more than our Gen 1's, but the guages still got the job done. One of these days, I swear, I am going to break down and buy a newer set w/o the mercury hassle. I'll prolly go with a Motion Pro.

Is this it? Seen Motion Pro alot on here

http://www.motorcycle-superstore.com/14/71/995/13078/ITEM/Motion-Pro-Syncpro-Carburetor-Tuner.aspx
 
I have both...the Motion pro...and the Morgan carbtune.....I like the carbtune better.
 

Yes, that's the one. I've seen them on Ebay for less than $75.00 delivered, and in fact, one of the dealers on Ebay is located in my home town. I could have driven over and picked it up for no waiting. lol

If I remember correctly, it was a Morgan brand that someone at the Topeka dyno tuning event was having difficulty with. I think one or more of it's internal metal sliders was hanging up and not sliding freely that day. Made me wonder about accuracy after it got older, and had some wear on it -vs- a fluid type. :confused2:
 

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