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Discussion Starter #1
Hi There!
I'm brand new here on the forum and just became the proud owner of a 97 birdie...
I have some car mechanics skills but most of all have 2-stroke motorcycle experience.
It's almost winter here in Belgium so time to get busy to prepare for summer!

I bought the bike from the first owner and it had been sitting for 2 years. Looked visualy good and well conserved but the battery was dead so i didn't test the birdie when buying...i know, stupid, but what could go wrong with this high standard, excellent designed and powerful bike as it was still fully standard??
Well...whole alot...

New battery...did not start...at all.
logical next step, fuel...
Nope, no fuel... i tested the vacuum line on the petcock by making under pressure with a seringue. Check, no fuel..dismounted the thing and yes...the membrane was gone. I ordered a revision set and abra cadabra! fuel...

i tried to start the machine with fresh fuel and it was turning on 2, later just humping on one cylinder and than...nothing...

Ok...decided to dismount the carbs to clean them entirely and 2 stationary jets were clogged up. i bought new ngk iridium spark plugs and
hallelujah... the bike went for all 4 power plants!!! happy as a 3 years old kid...I wanted to test drive offcourse, so i mounted the fairings and all the rest... Everything mounted, (allready 2 days later), helmet and gear on...startup....BRRRRRR... 2 cylinders out of order.

Frustration set inn...
i removed the spark plugs and they were wet.Only 2 exhaust pipes became hot. so there was something going on with the ignition...
replaced the ignition coils to make sure that wasn't the problem as the sparks were very weak...

checked and mesured the wirings, ground connectivity..all seemed to be fine..except that when i looked on the electric plan the negative and the coloured wires on the coils were switched. Following the workshop manual the negative should be on the coil connector with the green marking.
so i thought that maybe because of that the coils were toasted.

even with the new coils, weak sparks. it also looked like because of drowning in fuel the sparkplugs are gone, even after drying.

now what happens and made me wondering, mouth wide open:

When i ground the spark plug to the frame (good clean metal on the frame), there is no spark, or very very weak..( i tested 8 plugs to exclude 1 failing). but when i take the spark plug away from the ground, there are lightning strokes from the spark plug to the frame, even at a distance from 3 centimeters lightning strikes. so there is very strong high tension. when i make contact again with the spark plug to the frame the spark is gone. i cannot understand this. removing the spark plug from the ground again, lightning strikes...

Is there anyone who can explain this to my stupid belgian brain, because it does not seem logical at all...

I would realy apreciate your help...
btw, this forum is fantastic!

have a nice day!!!
 

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It has happened before that even cleaning and drying fouled spark plugs on these machines will not bring them back to life. New plugs will be needed in most cases.

Ensure the choke is off when the motor has warmed up. The lever should be full forward to be in the off position. I only need choke for the first start of the day. You should not need to twist the throttle at all to get the engine to fire.

Double check the coil spark plug wires are run to the correct cylinders for correct firing order. Coil #1 (left) fires cylinders 1 and 4. Coil #2(right) fires cylinder #2 and 3. (I think that is the correct set up?, going from memory here)

good luck.

T.
 

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I have learned that iridium plugs foul easily and don't recuperate well on bikes and autos as well. The carbs need the airbox fully assembled to operate correctly with an oem air filter if running stock jetting. Proper float height is crucial as well as making sure carbs are Thoroughly cleaned especially when they sit for years with that shiity ethanol fuel. Ultrasonic cleaner works wonders cleaning carbs. Ignition coils need to have the same resistance as oem on the primary winding of coil (between positive/negative)
 

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Yes the plugs will probably be dead, I discovered this years ago when working on a Bird engined track car. This can get expensive as well as frustrating.

To check out ignition systems without risking plugs I use one of these.
https://www.ebay.co.uk/itm/Ignition-Spark-Plug-Tester-In-Line-H-T-Test-Lead-Diagnose-Car-Engine/302694414740?hash=item4679fe3994:g:KpcAAOSw6Bhajsyt
This little tester proved invaluable last year when I was trying to coax a DR800 back to life (one cylinder, 2 plugs and 2 carbs) That bike had not started for 6 years and had defeated 2 previous owners!
FWIW a decent spark will jump +8mm.

In your position I would buy one of these testers (price of one spark plug) and check out the spark/ignition system before trying to run the motor again.
 

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Discussion Starter #6
Hi there!
Thank you kind people for thinking along with me! I truely do apreciate it!
First of all, the spark plugs were toast again...(250€ of sparkplugs later...)
I should have done step by step to define the problem but to take no risks to f#%* up the spark plugs again by drowning them i took some safety mesures ?
I replaced the coils (25€/each, specific year and model ) with 2 nd hand ones, indeed with 1 connection deeper than the other one. I also did a carb re-re build and installed a stage 1 jet-kit (in fact a dynojet kit which had been improved (On the dyno) for our lowland air conditions. Jet setting : 50-48-48-50... very rich but as the beasts allready run lean and next week my k&n and storm nero oval mufflers are coming in this seemed a good prep allready....
I also drilled the upper vacuum hole in the gas slide for quicker throttle response.

I re-cleaned all tubes, jets, holes and vents in the carbs and replaced the floater needles as well. Mixture screw on 2,25 turns...et voila...vroaaaap...for 2 minutes...
And than....4...3...2...! (Cylinders), not a flight test! Me unhappy.!wanting to set fire to my surroundings and the devil in my focus...
had to be fuel related...big sparks, other coils...
As a last thing before giving up that day (you know the, i’ll just check that and than you find something that motivates you again for a few hours, and that’s why your wife oftens hate you) i checked the intake ports from the carbs, engine off, lifting the slides by hand and trying to light with the torch between my teeth (how nice would it be to have 4 hands, and knowing to control them 2) and throtlle full open, i saw on carbs 2&3 a little , nearly invisible stream of fuel, running inside the manifolds...eureka!!! (Even with the new needles, i did not renew the needle seats) but a little tapping solved the problem. They didn’t feel at home yet... removed the spark plugs again, turned the engine over to remove excessive fuel, i will check my oil as well...
I did refurbish my diy ‘baxter style’ fuel delivery system and finally... my baby came alive..(indian native happy fire dance!!!) .first with the gas slides a bit dancing on their own.
Last week i managed to buy a 50€ synchronisation set on wish with fast delivery...
Not top of the bill but fair enough to do the job...and it did...

So yeah! Now just sit (oh man, i hate this) and wait for the muff’s and the k&n to come in...
It’s been a looooooong time waaaatiiinnnnn’.....

I would like to thank you guys again for the effort and energy to reply on my post...

Now back to business!
Next week it’s roling time (and freezing as well)...but a man’s got to do what a man’s got to do...even if its shaking and TRYING to heat up with a hot coco in the nearest cafe, wondering how you will get home alive...:)

Have a nice weekend!
And keep it (pretty) safe!!!
 

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That is good news. The sliders dancing is because the airbox is open(obviously). It has been my experience using a non oem air filter on cv carbs is a PITA to jet properly. YMMV.
 

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I would suggest investing in a AFR gauge if you can. It'll be a bit of a pain installing the bung. But it'll be loads of help mapping out the fuel curve. I'd suggest a Zeitronix unit. If it's to pricey then a couple good plug chop runs should get you some good insight. Biggest rule make only one change at a time. And keep thorough records of your setup and changes. And be patient.
Your shooting for light tan to grey plug color
 

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hi fromzaventem
you are paying waaayyyy over the odds for the plugs
i get mine from uk green spark plug co (also on ebay) for about 9 gbp each )
if you need local help let me know i have 2 bb and im in zaventem
 
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