Hot start problems - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
Engine / Exhaust / Cooling
\ From the radiator, through the case and out
the exhaust. If it has to do with the cooling,
engine or exhaust, discuss it here!

LinkBack Thread Tools Display Modes
post #1 of 13 (permalink) Old 02-10-2008, 06:03 PM Thread Starter
Join Date: Feb 2008
Posts: 8
iTrader: (0)
Unhappy Hot start problems

Before I ask my first question I'd just like to say hi. Hi.
I bought my bike 2 days ago. Cold start, no prob's. Rode it home & tried to start it to show my wife.
It turned over OK, loud pop out the exhaust but no go then ran battery flat trying to start her.
I put battery on charge. Meanwhile the bike obviously cooled down then fired up fine.
Put in new plugs, new battery, cleaned terminals.
Same again on hot starts. Tried a bit of throttle, loadsa throttle, bit of choke, no choke, half choke and some foul language but wouldn't have it.
Again, once cooled down then no prob's starting.
Looking at various forums it seems these bikes suffer starting woes.
Any advice greatly appreciated. Scared to fill up at petrol station incase it won't start.
surfbum is offline  
Sponsored Links
post #2 of 13 (permalink) Old 02-10-2008, 11:26 PM
Search Goddess
Dianna's Avatar
Join Date: Jun 2004
Location: Conway, AR
Posts: 1,998
iTrader: (2)
Just responded to the very same problem in this forum today..
If you do a search for Hot starting you will find numerous posts.
Weak battery is the usual culprit.
Iridium plugs also give a better hot start.
And then there is the pick-up coil adjustment if the other two don't fix it...
Possible solution to hard starting your VN7XX when hot.

Problem: Once my bike was good and hot, I would pretty regularly have problems restarting it after shutting it off for refueling, etc.... Once the starter was engaged, the bike would continuously turn over but never fire. After some e-mail discussion with Gary Versteegh from the main VROC board, I adjusted my pick up coils as described below. This seems to have eliminated my hard starting problems. This procedure may or may not solve your hard starting problems. Also, please note that the pick up coils are not designed from factory to be adjustable. This procedure requires modification to the stock components.

If you have any question, feel free to send me an e-mail to [email protected]. I will be happy to answer any questions.

Adjustment of pick up coils.
Remove the 3 phillips head screws on the left side. This will allow you to remove the pick up coil cover. You will need to place something under the bike to catch the oil although oil loss will be minimal. A rag was enough for me. Once the screws are removed, the cover should either come right off or you may need to pull on it. Mine was on pretty good and I had to physically pull on it to get it loose. The three screws and the cover all have separate o-rings. Once the cover is off, you will see the two pick up coils mounted to the stator cover inside two holes. They are mounted at roughly the 9:00 and 11:00 o'clock positions. Behind the stator cover, there is a rotor. You may need to rotate the rotor using a socket wrench on the shaft bolt in the center to align the small "plate" on the rotor with one of the pick up coils so that you can measure the clearance. Once you have measured one, rotate the rotor again so that you can measure the other. Gary recommends .020 clearance. Mine were about .030 or more. To adjust the clearance, remove the two screws which secure the pick up coils to the stator cover. You will most likely need to slightly elongate or slot the holes in the "ears" of the pick up coil mounting brackets. Gary indicates that a chain saw file works well for this but I used a rotary tool with a small grinding wheel on it. You will also see that there are 3 small protrusions coming out of the stator cover that each of the mounting
"ears" of the pick up coils fit into for proper placement from the factory. You will most likely have to knock the one closest to the center off to be able to make the necessary adjustment. A sharp chisel works well for this although you may want to cover the holes in the stator cover with something to prevent the little piece from falling inside the engine. Once the protrusions are knocked off and the holes are elongated, it is time to put the pick up coils back on. Set them back in their holes and start the screws. Place your .020" feeler gauge between the coil and the rotor "plate" and tighten the screws. Once you are satisfied with the clearance, tighten down the screws and do the same with the other coil. Gary recommends that you use both an impact screw driver and lock tite on the screws. I don't have an impact driver but I did use lock tite. Once both are set, put everything back together and test it out. I don't have a digital camera or I would have taken and posted some pics but you can look through the pictures in the Clymer's manual to get an idea of what I am talking about. In my manual (I assume they are all pretty much the same) the pictures on pages 296 to 302 should give you an idea of what I am talking about.

Note: This adjustment DOES NOT require removal or tilting of the engine. Just removal of the side cover held on by the three phillips head screws on the left side.

I would also add..
Cold start procedure is..
full to partial choke, NO throttle, hit the start button.
Hot start procedure is..
NO choke, and just a blip of throttle as you hit the start button

Conway, AR
Patriot Guard Rider
2000 VN750 Sere (Serendipity)
1990 GL1500 (Ole Blue)
1986 VN750 EVie (project bike, heavy custom)
VROC # 11628 / 25000-H
ARVROC # 12 Coordinator and Crowd Control
OKVROC # 18 (H)
TNVROC # 45 (H)
Dianna is offline  
post #3 of 13 (permalink) Old 02-11-2008, 01:36 AM
Join Date: Jun 2007
Posts: 185
iTrader: (0)
I put a Maintainence Free Gel Battery in mine and never had hot start problems again.
vn750joe is offline  
post #4 of 13 (permalink) Old 02-11-2008, 07:34 AM
Simon's Avatar
Join Date: Mar 2007
Location: London
Posts: 77
iTrader: (0)
Hi SurfBum
Nice to see another UK owner on the site.
If you don't have a cold start problem then you are not seeing those issues carried over on to hot starting and the problem is a different thing happening - as you can see from the proposed solution.
I had hot and cold starting issues and they interacted, but the cold problems are now fixed and I no longer notice the terrific backfires that hot starting used to produce. All in all I decided to live with it. Just wait for the engine to cool down and take your time. Sit on the bike in some posey leathers looking like you are in control of the situation and thinking about how cool you look. Press the start button from time to time for a short burst only. Don't keep churning it. Suddenly the engine will roar into life and off you go.
Simon is offline  
post #5 of 13 (permalink) Old 02-11-2008, 12:22 PM Thread Starter
Join Date: Feb 2008
Posts: 8
iTrader: (0)
Thanks for all the response. Great to see a forum where you actually get help & advice.
Seems that I also have a cold start problem.
Tried to start the bike at a cold & frosty (bike kept in garage) 5am this morning & ended up having to take the van.
However I did notice when I first bought the bike is that the starter seems to turn over slower than I would have expected, even with a new battery.
Is this normal?
My theory is that the starter is using more juice than it should & therefore there is not a big enough spark is being generated to fire the engine....
Any thoughts.
surfbum is offline  
post #6 of 13 (permalink) Old 02-11-2008, 12:42 PM
and the Adventure Cycle
hyperbuzzin's Avatar
Join Date: Jun 2004
Location: Western PA
Posts: 6,138
iTrader: (1)
What year is the bike? Might need to clean the starter out if it's a good bit older.
Build-up inside there can really cause problems with it using all the power it's getting.

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

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

Author Unknown
hyperbuzzin is offline  
post #7 of 13 (permalink) Old 02-11-2008, 01:39 PM
Simon's Avatar
Join Date: Mar 2007
Location: London
Posts: 77
iTrader: (0)
That was exactly my problem - starter turning too slowly; in this case because it was mucky. The workshop put it in a lathe and skimmed the muck off and now its fine. Maybe that had been the only problem, but along the way I fitted a new R&R - which I relocated - a gel battery and iridium plugs. Although I didn't measure the volts I did think that the battery was not being charged properly and I am glad these things are done.
I suggest you sort the starter issue first as that might also solve the issue with hot starts. If the cold starts are sorted but the hot starts are still tricky you can then try iridium plugs - they didn't work for me, but you can see from this forum that they do work for some people and its an easy fix.
Simon is offline  
post #8 of 13 (permalink) Old 02-12-2008, 03:39 PM Thread Starter
Join Date: Feb 2008
Posts: 8
iTrader: (0)
Hi, Thanks for the advice guys. My bike is a '93. It's well worth giving the starter & connections a once over.
Early days yet but after reading your first reply about short bursts on the start switch I had a go on both hot & cold starts.
As I say, early days yet but it seemed to do the trick. Cold start. No choke or throttle. Tapped the start button. When it fired 2nd or 3rd time cracked the throttle open then put choke on.
Time will tell??
As a matter of interest. Which part of London are you?
I been living in Birmingham for 20+ years but originally I'm from North London, West Hendon where my parents still live & my bruvver is in Edgware/Burnt Oak.
Thanks again

Last edited by surfbum; 02-12-2008 at 03:44 PM.
surfbum is offline  
post #9 of 13 (permalink) Old 02-13-2008, 04:53 AM
Simon's Avatar
Join Date: Mar 2007
Location: London
Posts: 77
iTrader: (0)
With a name like surfbum I had you down as being in Devon or Cornwall. I have been just off Borough High Street for 20 years, but moved yesterday down to Tooting & will prob move to Bermondsey in a couple of months. I'm on nodding terms with Hendon - esp Hendon u/ground station & the High Street. Very pleasant round there. Only know Edgware from going down the A5 years ago. Birmingham has improved enormously over the last 10 years - the centre is really pleasant now. Am originally from Coventry myself so can talk a bit of Brummie.
Simon is offline  
post #10 of 13 (permalink) Old 02-13-2008, 03:34 PM Thread Starter
Join Date: Feb 2008
Posts: 8
iTrader: (0)
Wish I was in Devon or Cornwall. Since travelling around Australia for 5 months where I learnt to surf then going on to spend 6 weeks in Hawaii I got the surf bug big time.
Yep, agree with you. Brum has come along way. We are in Erdington if you've heard of it?
Don't want to sound dumb but whats the R&R? Seen it mentioned a few times. If I'm looking at the right thing i think mines been relocated by a previous owner judging by the home made brackets.
surfbum is offline  
Sponsored Links


Quick Reply

Register Now

In order to be able to post messages on the Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Once registered, your User Name"cannot be changed". We can make exceptions within 7 days, but after that, it is set in stone.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome