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post #1 of 9 (permalink) Old 05-23-2006, 11:14 PM Thread Starter
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Question Jerking in low gears

I bought a 94 with 4K miles on it last year. The owner had not ridden it very much in several years. For that matter at all considering the age and milage. When I am in lower gears it is very rough and jerky. Once I reach
5th gear it does fine. I have added carb cleaner and its a lot smoother but I still have problems. My boyfriend has changed the spark plugs also.
Any suggestions or idea why it would do this?
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post #2 of 9 (permalink) Old 05-23-2006, 11:20 PM
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Since it sat for some time there's a good chance that the carbs are gunked up/plugged up...and may need to be removed and taken apart and deep cleaned. You can keep adding SeaFoam gas additive to see if it will help open the passage ways inside the carbs but that may take some time. Chances are that the gas tank has junk in it also so you may want to remove it and clean it out also...just to cover that since you'll be trying to fix the carbs as well.
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post #3 of 9 (permalink) Old 06-20-2006, 12:08 AM
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If the bike sat for a long time with gas in the tank you might want to check the gas tank for internal rust. Mine rusted quite severly while awaiting rebuild. Big Mistake!!! The rust residue will clog the petcock!! Or worse, damage its internal parts. Don't ask me how I know.
I used the Yamaha rust remover system and have had no recurring rust issues. Some people prefer Kream as it coats the tank at the end of the process further protecting it from rust.
Just my .02

Jim W
93 VN 750 "Ursula"
Moved R/R 08Sep06
R/R rewire 17Feb07
New R/R, Installed 14Jun08
New Stator installed 10 Jun08
Maintenance Free Battery 12Jan08
21480 Miles
VROC #8542
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post #4 of 9 (permalink) Old 06-21-2006, 07:25 PM
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Angry Have the same problem with a brand new bike ? ?

Last week I bought a new VN750, and it would die if I didn't give it
a lot of throttle when starting out, also in first gear it is rough and

Called the dealer and they said it would be better at around 500 miles,
and they would look at it then, but I have to take my skills test
with this bike and I need it to run smooth in first gear at low
speed for the cones, etc... Wow what a dealer!

Also I didn't get an owner's manual with the bike, a manual for
a 1000cc Concourse was somehow put into the packet, the dealer
says it was the factory and the Kawasaki Inc. says it was the
dealer. . . So I have ordered a Haynes Service Manual, because
it could be quite awhile before I recieve a vn750 owner's manual.

What is the fairly large shiny black knob on the left hand side of the
bike? It looks like a carb adjustment of some type? Air or gas ?
How is it adjusted?
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post #5 of 9 (permalink) Old 06-21-2006, 08:31 PM
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I think you are talking about the idle speed adjustment knob. I don't know if your problem is this, but my tank had some water in it a while back from when it was purged to weld it, and would have this "bogging down hesitation" if I slowling increased the throttle when starting off. If I gave it a lot o throttle, it would shoot off like a rocket. The hesitancy originally started at 2-2,200 RPM's, then it sort of moved to around 3,000 RPM's, and finally moved to 3,500 RPM's but it was very faint. It was weird, as over the course of about 15 miles, the "bog down" range moved like I said. Then it went away and I haven't had any problems since. I added some "Heet" water remover I got at a gas station.

I also have to ask you. I started with a moped and rode the hell out of it, then took a rider course when I went to upgrade to something a bit larger than the 50cc's I was accustomed too. They included exercises on all the skills you do and then you do the skills test and all with a 250 cc bike that you rode on for the past 2 days. I found it to be a great deal, and when I went to the DMV the next day, I just paid 1$ to get the letter "M" put on my license and then went off to buy a motorcycle. I can't imagine taking the test with the 750. Have you looked into what one of those BRC courses could do for you? I think there are also BRC "1.5" courses that are mostly a test rather than the whole training thing for riders who already know how to ride but want to take the test.
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post #6 of 9 (permalink) Old 06-21-2006, 08:49 PM
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MC safe driving school

Yep, I can't imagine it either, but I went down to Department of licensing
and passed a very difficult written test in hopes of saving a few bucks on
the school.

I know what you mean I took the test in Montana, California, Arizona and
Oregon on a Kaw 175cc and it was very simple. I wish I knew where I
could rent a bike for the day to take the skills test. The Washington State
skills test looks very difficult in the book, but in actuallity there isn't
enough room at Dept of Licensing to do all those maneuvers. I plan on
going down this week to watch the skills test to see if I can make it
through with my large VN750.

Well if I fail the skills test I guess I can take the MC Safety school, I've
seen them practice and it looks easy on those Yamaha 200's with the
rear fat tire (made in Brazil), and Yamaha 225's.
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post #7 of 9 (permalink) Old 06-22-2006, 04:36 AM
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Kinda off topic, for which I apologize.....

I recently took my riding test (in PA) on the Vulcan. Wasn't all that tough, but I'm used to riding some really tight/slow dirtbike trails, so that probably helped me a bit.

For the test I took, the toughest thing to do on the Vulcan was 3 consecutive figure 8's. I'm not exactly sure what the size of the area they gave to do it in, but I think it was about 2 parking spaces.

I'll put this back onto the topic now....

Ladyblue, Have you checked the airfilters?

AKA: Tim & 'The Adventure Cycle' VROC #24567, NEVROC, SteelCity VROC

"When life throws you curves,
Aim for the apex."

Author Unknown
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post #8 of 9 (permalink) Old 06-22-2006, 10:13 AM
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Sorry to go back off topic, but you might also try some CDL schools/testing areas. There is one here that both rents a 250cc bike and administers the tests.
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post #9 of 9 (permalink) Old 06-23-2006, 10:05 AM
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Road Test

Check your local community college. In Cheyenne the state and local CC have worked out a partnership. Two day class with bikes provided and when you pass the Motorcycle safety foundation course it counts for your skills test. Result less problems for DMV and basic skills trained new riders. As we two wheelers get enough bad publicity for higher accident rates. Every thing done to promote motorcycle safety helps and we get new riders to keep the spirit alive.

Dennis Huff
Cheyenne, Wy.
05 VN 750
KURYAKYN grips, helmet locks, and highway pegs
Spitfire windshield
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Highwayman gelseat with Protac backrest
self canx turnsignals
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Jardine 2 into 2
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