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bonnie running problems

1870 Views 11 Replies 8 Participants Last post by  webonnielad
Any ideas would be helpful ,am working on o6 (new)bonnie with 4000miles on it .It has a running problem at high speed .At over 4000 rpm with a steady throttle and when hot m/c starts to hesitate and stumble like its running out of fuel ,it seems to be intermitant ,so cuts in and out and only under load(not on bench)
so far fuel has been checked and replaced,tank changed,breathers checked,carbs changed,pick up changed, ecu(black box )changed,air filter checked ok, AI system junked ,silencers changed,loom checked for continuity ok,air gap checked ok,valve clearances checked ok
has anybody else had this problem or similar would be interested in all views or ideas ta
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could be too rich on the needles possibly, maybe mains?

what's the jetting you're running?

Also, it could be a bad coil.

[ This message was edited by: sweatmachine on 2007-01-16 13:31 ]
coils have been checked all ok ,looking at carbs they are totally standard jetting and needles is the next thing we are going to play with its just odd that this the only bonnie ive come across with this problem .they normally are trouble free
Boot clamps tite- then it sounds like sticky/ maladjusted float? :???: :hammer:
I would go with the float level as well. Also, drain the tank and remove the fuel valve to see if it has debris resricting flow and replace the fuel filter.

all sounds good will let you know the outcome ta chaps
..... in-tank fuel filter at the gas valve clogged?

Bike been sitting too long and a bit gummed up? Try putting 4 ounces of Seafoam in the tank and drive the snot out of it.

I found the hardware on the boots between my carb's & intake to be loose one day..... pure happenstance and coincidence that somebody posted to someone else to check their's.... and it addressed a problem that JUST snuck up on me from outa nowhere! Synchronicity babieee!

Has it got a used ProCom igniter on it? I have one with over 20,000 miles, but it's no longer on MY bike...... you can venture a guess as to why.

How about your battery cables? Mine were working loose on a goat trail, started to run intermitantly, stumbled, then stopped.
But...did you change gas caps?? Seems like an unusual number of problems have been mentioned on this forum about problems withy '06 gas caps not venting. If the tank is not venting properly, it will appear to be running out of fuel because that is what is happening.

gas tanks have been changed completely including caps this was where i started first,with respect to the float levels i have swapped the carbs from another standard bonnie which runns fine , this still has not helped
I am still wondering about your coil. I remember that mine still showed spark but it wasn't until the dealer swaped it out that it showed as being bad.
You mentioned checking the coils.....Try using the coil from you the other bike.

This is gonna sound pretty silly, but I had similar problems when I purchased a locking gas cap to replace the original.

The breather in the cap didn't work as well as the original and was causing a partial vacuum in the tank, slowing down the fuel delivery rate.
Sounds to simple to be believable, but hey you got nothing to loose, so check it any way.

Good luck keep the faith

Jon (UK)
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