Hello Guest User,

Please feel free to have a look around the forum but be aware that as an unregistered guest you can't see all of it and you can't post.

To access these 'Registered Users Only' areas simply register and login.

Opinions please.....

Need help restoring, building, or finding then try here.

Moderators: KeithZ1R, chrisu, paul doran, Taffus

Message
Author
Monk

Opinions please.....

#1 PostAuthor: Monk » Tue Jun 23, 2009 9:38 pm

So....my z1000a2 with Harris pipe and pod filters isn't running quite right.

Firstly I should say that the carbs have been cleaned and balanced and I don't think the jetting is a mile out.

If you ride the bike gently it runs like a new one.
Starts on the button, hot or cold, ticks over lovely and revs clean as you like.

The problem is that if the bike is 'willing' at low revs it feels rather 'unwilling' when pressing on.

On a fairly open throttle, probably about 80/90mph it spits back through the carbs and feels as though it is working hard to hold that sort of speed.

It's very difficult to put into words....it doesn't mis fire, nothing really goes wrong (except spitting back) it just feels uncomfortable and a bit harsh at higher speeds.

Any mind readers or crystal ball gazers out there ?

User avatar
Ginger Bear
Hardcore
Hardcore
Posts: 6850
Joined: 16th Dec 2008
Location: In the Dark.
Contact:

#2 PostAuthor: Ginger Bear » Tue Jun 23, 2009 9:48 pm

Cam timing :? Not hard to check, one cam could be a tooth out :shock:

Monk

#3 PostAuthor: Monk » Tue Jun 23, 2009 9:55 pm

GB

I am no mechanic....would incorrect cam timing allow the bike to run well at low revs though ?

User avatar
MaineKZ
Custard Cream
Custard Cream
Posts: 792
Joined: 30th Aug 2005
Location: A safe distance from High Wycombe

#4 PostAuthor: MaineKZ » Tue Jun 23, 2009 9:55 pm

Sounds a little like a problem my first Z1B had when I first picked it up. Proved not to be carbs but the mechanical ignition advancer that was semi-seized. May be worth checking

User avatar
Ginger Bear
Hardcore
Hardcore
Posts: 6850
Joined: 16th Dec 2008
Location: In the Dark.
Contact:

#5 PostAuthor: Ginger Bear » Tue Jun 23, 2009 10:00 pm

I believe it could happen, but as Maine says the advancer could be at fault, n' that would be easy to substitute. I'm sure someone has one to lend you.

User avatar
BShaw
Area Rep.
Area Rep.
Posts: 714
Joined: 22nd Dec 2001
Location: Westgate on sea

#6 PostAuthor: BShaw » Tue Jun 23, 2009 10:13 pm

check the free ones first, cam and ignition timing etc.......Has this just happened what has been fitted recently what have you been fiddling with ?
Baza

I had the day off from school when we did inglish.

Steve Cooke
Hardcore
Hardcore
Posts: 1612
Joined: 18th Mar 2007
Location: Southampton

#7 PostAuthor: Steve Cooke » Tue Jun 23, 2009 10:19 pm

If the cam timing was a tooth out it would be noticeable throughout the range.

m1ks
100Club
100Club
Posts: 297
Joined: 11th May 2009
Location: HIGHLANDS
Contact:

#8 PostAuthor: m1ks » Tue Jun 23, 2009 10:50 pm

Check the ignition advance first of all, straightforward, if all's well there i'd look at fuel air.
I'm assuming along with the pod filters and performance pipe you rejetted accordingly and set it up or had it set up?
If not then this is the first port of call.
If you did then check for air leaks around the inlet manifold rubbers, have someone hold the throttle open and give the rubbers a good squirt of WD and see if the engine note changes.
If OK there i'd still suspect leaning out at high revs so you could try raising the needle a clip to richen it at wider throttle or jumping up another jet size, some performance upgrades often call for a needle with a different taper.
if you have access to a garage with an exhaust gas analyser you can get them to check the burn at high throttle, even better if they have a rolling road as you can do it under load, this will show if you're definitely leaning out.
A good pointer of leaning is when it bogs out under sudden harsh accelleration above about 6000rpm (ish).

User avatar
Pigford
Hardcore
Hardcore
Posts: 13314
Joined: 2nd Jan 2006
Location: North Dorset

#9 PostAuthor: Pigford » Wed Jun 24, 2009 7:54 pm

Nick....... may well be worth the £40 for a dyno run matey boy :wink:

Could be main jets or ignition breaking down at top end :?:
And on the 7th day... Zeds were created!

User avatar
Kev1R
100Club
100Club
Posts: 494
Joined: 7th Apr 2008
Location: Nottingham

#10 PostAuthor: Kev1R » Wed Jun 24, 2009 9:21 pm

Just a suggestion:

Coils tend to struggle under load when they are on their way out...

m1ks
100Club
100Club
Posts: 297
Joined: 11th May 2009
Location: HIGHLANDS
Contact:

#11 PostAuthor: m1ks » Wed Jun 24, 2009 9:39 pm

oooh buggery,
knew I meant to add summat else to my above post, seeing the coils one reminded me.

Check your battery, make sure it's got good charge and the reg/rec is behaving and not giving too little or too much, (if it peaks at well over 15V or well under 13V either the reg/rec or battery needs attention, a duff battery not taking in charge, (one bad cell e.g.), will make the reg / rec work harder thereby killing the battery and overheating and knackering the reg/rec.

Usual battery checks, charge on a charger, check you're in the 12.5 - 13V area, leave overnight see if voltage drops excessively, do the same on to see if anythings causing battery drain.

Also, as the other poster said, check the coils, older units can break down under use and heat build up.


Return to “Bike Help”

Who is online

Users browsing this forum: No registered users and 20 guests