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Discussion Starter #1
Hi guys, got a 1991 Vulcan750 this week and have a couple questions. It runs great until I hit about 60 mph then it seems to buck and stumble a little. If I throttle it, it smooths out until I'm cruising at a consistant speed.
I did add some Seafoam to the gas today after a fill up. I bought the bike from my cousin, who hasn't ridden it in a few weeks.

Also, is it normal for the headlight to dim when it's idling and then go brighter when I rev it up, or should I be looking for a battery soon?

And on a side note, is there a certain website you guys use to find riding gear, like a mesh type jacket with some armor?

I really appreciate it, thanks.
 

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Welcome to the forum. You will find many great and wise folks on here. You are on the right track with the seafoam to give her a good cleaning I would run it in a few tank fulls to be safe. Another thing you can check is the small vent tube in the right breather cover to see if it is out of the breather or bottomed out. When you check it you should cut the end in the breather cover at a 45 degree so it doesn't bottom out.

The headlight will dim a bit where the stator isn't putting out as much at idle rpms but it would be wise to test the battery and if you need a new one get a sealed battery with higher cranking amps. You can find a lot of this info in the versus threads.
 

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Welcome to the forum. You will find many great and wise folks on here. You are on the right track with the seafoam to give her a good cleaning I would run it in a few tank fulls to be safe. Another thing you can check is the small vent tube in the right breather cover to see if it is out of the breather or bottomed out. When you check it you should cut the end in the breather cover at a 45 degree so it doesn't bottom out.

The headlight will dim a bit where the stator isn't putting out as much at idle rpms but it would be wise to test the battery and if you need a new one get a sealed battery with higher cranking amps. You can find a lot of this info in the versus threads.
As they said on Family Fued ,Good answer ^
 

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Old Twistie Sticks Rider
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I agree with the above ^, but would also like to add, I think the idle speed is around 1,100 rpm (think that is right), and if you are lower that would cause the headlight to dim also...
Just make sure your idle speed is adjusted up to Spec. ... Others correct me on the 1,100 rpm if that is wrong...
Have a good one...Old Dog...
 

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Correct Old Dog. The idle should be between 1000 and 1100k.

I forgot to add the other alternative to seafoam and IMO a better one. K-100 mg It is excellent stuff and formulated specifically for the new ethynol mixed fuels. I have been using this stuff over the seafoam and I do see a big difference. Some may say "Blasphemy!" but I have done extensive testing and found K-100 mg to be the better choice.
 

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Discussion Starter #8
Thanks for the replies guys. So this breather cover, is that where the air filter is? Speaking of, the foam stuff with the air filter is pretty dirty, should I replace that stuff?

Yeah, I think the idle is around 800 or so right now so I should find the idle screw and adjust it in right? Sorry if these questions are dumb, I have the service manual, just havn't had time to look at it due to 2 family reunions this weekend (ugh). Thanks
 

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Sparky!!!
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the foam air cleaner should be able to be cleaned with mild dish soap, wrung out and air dried. then wet the foam with 30wt engine oil. and yes the breather cover is better known as the ear or air box.
 

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Linkmeister Supreme
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Welcome to the Vulcan madness.

The idle adjust screw is down on the left side and has a black knob for finger adjustment.

Idle speed should be set at 1100 rpm +/- 50 rpm.

The stator/alternator does not charge at idle speed, so the headlight will dim until rpm increases to 2K or more.

Here is the MF-AGM battery you want when you need to replace your`s:
http://cgi.ebay.com/ebaymotors/Deka...em&pt=Other_Vehicle_Parts&hash=item3eee173adb

If you have a K&N filter on your car, and have a re-oiling kit for it, I suggest using their spray oil on the Vulcan filter. It is very easy to over oil the foam filter by pouring on engine oil. This will restrict the air flow, and cause a rich fuel mixture. When cleaning the foam filters, dry them by pressing between layers of a towel. Do not twist or wring them out. IIRC, there are instructions in the service manuals, and I`m sure there is a thread here too.

Here is what is in the Vulcan verses:
http://www.vn750.com/forum/showthread.php?t=1060
 

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is K-100G a fuel stabilizer as well as a fuel system cleaner?
Yes slim it is a fuel stabilizer and lasts much longer then seafoam. In another thread a few months ago I posted my findings from testing seafoam, stabil, and K-100 mg side by side and the K-100 had the best results. I'll try and find the thread and post that as well.
 
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