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Discussion Starter #1
First off let me say thanks to all who contribute their knowledge here, I am a new member and this kind of stuff really helps out a guy like me. I have a 97 VN 750 with about 23K miles. The guy I bought it from said it would run like crap sometimes, but then would be great. It ran great for me the first two weeks I had it, then I couldnt keep it running, then it would be fine. I have added Seafoam and am currently running that in the tank right now, is there any other obvious things I should be checking??? I am new to motorcycles but not new to working on engines so any info would be great.
 

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what year bike? I just replaced a couple vacuum lines on my 86= big difference.
 

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I would first check the color of the sparkplugs to determine how the carbs are working. They should be light tan or grey. If one or both are black or wet you are running too rich. You may need to adjust the air/fuel mixture. You may have weak plugs or a bad spark plug wire. Iridium plugs work great. The good then bad condition could be a sticking carb float, flooding one carb. If you switch gas stations you may be getting moisture in the gas from one of them. These are my obvious first looks.
 

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Linkmeister Supreme
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If you do need new plugs, get the NGK Iridium DPR7EIX-9.

When you need a new battery get a Maintenance Free- AGM.
This Deka is a good one:
http://cgi.ebay.com/ebaymotors/Deka-ETX15L-Powersports-AGM-Battery-100-NEW-/270282472155?cmd=ViewItem&pt=Other_Vehicle_Parts&hash=item3eee173adb

The next thing to do after getting the engine running properly is check and lube your rear splines before riding too far.
See fergy`s spline lube link here:
http://www.vn750.com/forum/showthread.php?t=17274

Since you are new to wrenching on motorcycles this link may interest you:
http://www.dansmc.com/MC_repaircourse.htm :)
 

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Discussion Starter #6
Starts good hot, a little rough cold, yes i do use the choke, idle seems alright no noticeable hesitation, tank looks good no rust that i can see. Definitely going to start with a good tune up, have some chugging from the pipes on decel as well. Will change the plugs and try to tune the carbs, manual is on order. Thanks to all for the input, makes things much easier.
 

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Discussion Starter #7
Now this damn thing actls like its starving for fuel, idle is very low and doesnt want to stay running. Been riding non stop for a week, just put in fresh gas from a different gas station. This is nothing like it was before. Waiting on my parts to get here for a tune up, I am thinking I have carb issues. The PO said it would do this sometimes and was told that it could be a clogged gas vent tube. Until I get some new parts on this thing, I think I am screwed. Plan on doing electrical checks this weekend. I am running out of riding time here in Washington so I want to fix this quick!! Any other ideas?
 

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look up POOGS... it is sounding like you have a vacume issue fromt he tank.. check you hoses then useing some WD40 check your boots at the carbs... how does it idle?
if this dosn't do ya.. run strait seafoam thru the carbs or pull em and clean them. check and clean your plugs. check all of your ground points ont he beast and then see what you got.
 

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Discussion Starter #9
Thats the plan, waiting on my parts, no one seems to carry the iridium plugs. Will have to spend some time on it this weekend....
 

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If only it had 6th gear..
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Now this damn thing actls like its starving for fuel, idle is very low and doesnt want to stay running. Been riding non stop for a week, just put in fresh gas from a different gas station. This is nothing like it was before. Waiting on my parts to get here for a tune up, I am thinking I have carb issues. The PO said it would do this sometimes and was told that it could be a clogged gas vent tube. Until I get some new parts on this thing, I think I am screwed. Plan on doing electrical checks this weekend. I am running out of riding time here in Washington so I want to fix this quick!! Any other ideas?
Gas vent tube.... First check the hose off the back end of the tank that goes down by the battery. Some guys have said that they found the end clogged with crap because it is near or even touching the tire. I used A couple of feet of weed whacker line, fed it down the hole by the gas cap until it popped out at the back of the tank. Then two screws and the cap comes apart to check / clean the little check valves in there. Careful, the parts can pop out when you crack it open. You've checked the carb vent that goes into the right side ear? that can be bottomed out against the case and cause fuel issues too. Hope you get er running nice this weekend
 

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Discussion Starter #11
Anyone know what sizes the vacuum lines are? I may just replace them all if time allows..... Been trying to find a schematic of some sort but no luck there either, is there one in the Verses? I cant seem to find it.
 

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Runs Rough Sometimes

Hang in there, these guys will help you get that bike running. There is some place a loose part or an air leak or some other little thing giving you fits. Two things will happen. You will get to know your bike better than you ever thought you would. and your self esteem will soar.

Mcneuby :beerchug:
 

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I beleive the vacuum lines are in metric sizes and are different. the one I just replaced comes off the carb on the right side of the bike and goes up through the frame to the back of the tank just below the seat to a little canister, plus I replaced the fuel line from the petcock to the carb, I just took bothe in to napa and we found one that was close and cut it to length and voila, she is running good again. $2.00, I hope you are so lucky!
 

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Discussion Starter #14
Okay, here is what I have found so far. Tore the bike almost completely apart. Found all plugs very fouled, wet and black ( 2 autolites and 2 champion), wires look good, cleaned all vacuum lines and vent lines. Found the boot between the right carb and head was wet and seen a vacuum line from the right card to the canister by the battery had been zip tied on and had a crack. I replaced that, replaced the plugs, since I was deep into the work I decided to relocate the R/R. Took the tank off to inspect the fuel lines and found the PO has 2 inline filters set just beloew the petcock that are zip tied on. I have seem some people here that say thats okay and some that say no way...... I think I am going to get rid of them after I buy more fuel line and clamps. I am still having some idle issues, going to try carb cleaner through the drain hole and reset the feed screw. Hope this will cure it.
 

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Runs rough some times

How is it coming? Have you been able to get it running the way you want? I guess I want to know if it is running yet. I had a Honda a few years ago that gave me fits until I found a leak in the system,

Mcneuby: :(
 

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You may not have good vacuum at the pet cock, or vac lead. See that you have a good flow of fuel to the carbs, put a good vacuum to the pet cock and drain the gas at the bottom of the carbs into a class jar to see what you have. You may need to reset you air mixture screws. Also look into syncronizin the carbs, several good threads on how to do this. Did you check your air filters? Also look at the vac line that goes to the right air filter, that is if you still have them.. Lots of luck in finding the trouble.
 
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