FZRSupport: the FZROnline Archive

READ PART ONE FOR FULL STORY...PART TO FOR SHORTENED STORY IF YOU DONT WANNA READ


#1so here is how it goes...
My bike was running great after the r6 exhaust swap.
My carbs were freshly synched and everything.
a week or so ago we were talking about fuel octane and ignition advancers and people said there bike runs best at this and that octane, so a week or two ago i put 89 octane in instead of the usuall 87.
everything was fine until about 4 days later, the bike seems to have dead spots in throttle but it would still hawl ass in higher rpms.
now friday night, I met up with my brother and a 6 of his friends because we all were going to go to a club about 50 min away from home...we went to one of his friends house to park all the cars so we could all go in my brother durango...the road to his house is an extremly bumpy dirt road that is about 200 yards to his house where I parked my bike. it was about 10:30pm now...
we all went out to the club and danced with super fine tail and got back at about 5:30am.
I went to start my bike...it wouldnt....I tried and tried and about 20 minutes later I got it to want to start but it wouldnt hold. finally a little later I got it going but it seemed as if it was running only on three cylinders so I started to pull plugs and find the gremlin...the thing is, all plugs worked and the bike ran worse with each one pulled seperatly, so I knew it wasnt spark...I was thinking weak spark but ...
ever since though, it sounds and runs like its only on 3 cylinders...the only difference is that it still idles at the same tone, it just as a slower beat to it.

I talked to the motorcycle mechanics at the shop by my house, he told me to check my carbs and float hieght.
I went home and ripped out my carbs and noticed there was fuel on the inside of my boots and on the underside of my carbs...so I called the mechanics and he said "it sounds like its putting to much fuel in and its not burning it fast enough" he told me to bring it in for the pros to work on it but I dont have any money...
I checked my float height...21mm...everyone else seems to be running 24mm, so I set mine at 24 and made sure my jets wernt clogged and threw the carbs back on with a grin thinking I solved the problem but NOPE...still runs the same...no difference what so ever.

I dont know what it could be...



#2


My bike was running great...crap load of power
I road my bike over alot of bumps...then parked it...when I tried to start it the next morning, it wouldnt start...
after about 30 mins I got it running BUT...
My bike sounds and runs like its on 3 cylinders, but all the cylinders are working and all got spark.
checked carbs...nothing.
any idea what could be the problem??

Have you resynched since putting on the header? When you blip the throttle does it hang before is comes back to idle? From what you describe it still may be a bit rich. Once you get the part you need for your carbs I suggest resynching them again. At least that's what i would do first. Also have you checked for resistance on the coils? One of them may be going bad.

run hotter plugs , as was mentioned you prob running rich .. check your plugs if they fouled ?

alot of my richness went away when I put the floats at 24mm.
when I reved it way high before, alot of black smoke would shoot aout of my can, but now there is very little if not no smoke at all...
I havent resynched it since the headers, but why would this happen just now? and so suddenly? the bumps I went over maybe bounced them unsynched??

I just dont get it...Ill have to check the wiki about checking the coils...Ill borrow my bosses multimeter so I can check them.

im really worried its gonna be something with the motor...if it is, then I have to wait a long time and then Im just going to get the yzf valve head and stuff and do the 660 conversion if im going to have to tear down the motor and find a bad piston anyway...

PIMPMYFZR wrote:run hotter plugs , as was mentioned you prob running rich .. check your plugs if they fouled ?

plugs all work and have spark.
would would I need hotter plugs if my bike was just running perfect on the plugs im currently running?

Have you checked your carb boots? Perhaps they cracked and you have a vacuum leak. If you have a infrared temp gun, you can read each exhaust runner to narrow down to a cylinder if that is the case.

I probly started all your hassle with the ignition advance.
My bike on our high octaine is not as good as blend of low octaine and avation fuel.
This is the burn time of the high octaine that gives me lower horses on the dyno.
The problem is with the flash time of different petrol.
Low octaine has fast flash time.
Avation fuel has the slower flashtime but blends work as the low octaine fuel flashes and causes the avation fuel to follow suit.
This was the reason i wanted advance as i wanted to go to 50/50 with high octaine and avation fuel.

soory if i open a can of worms

megaloxana wrote:Have you checked your carb boots? Perhaps they cracked and you have a vacuum leak. If you have a infrared temp gun, you can read each exhaust runner to narrow down to a cylinder if that is the case.

my boots are old and all of them are cracked but i dont think there is any leaks...there is only cracks on the outside.

im think im going to pull each plug one by one and see which one will make my bike run less worse than the others when I pull it and that will point me to which cylinder it is......get what im saying?

I dont have a temp gun

Touch test with new finger each time then work out which finger hurts the least.LOL

shredex wrote:I dont have a temp gun

Easiest way I've found so far is to get it running and flick a little water on the header, watching each tube and see which one takes the longest to evaporate...

mossy1200 wrote:Touch test with new finger each time then work out which finger hurts the least.LOL

i've actually done this many times when i had ignition problems. One cylinder was misfiring and it was the one that didnt burn my hand. If you do it when your pipes are cold, you can feel which ones heat up faster than the others. The stragler you will still be able to touch while the others will be too hot to touch.

megaloxana wrote:

mossy1200 wrote:Touch test with new finger each time then work out which finger hurts the least.LOL

i've actually done this many times when i had ignition problems. One cylinder was misfiring and it was the one that didnt burn my hand. If you do it when your pipes are cold, you can feel which ones heat up faster than the others. The stragler you will still be able to touch while the others will be too hot to touch.

yep that has worked for me as well

after i find what cylinder it is though...then what??

shredex wrote:after i find what cylinder it is though...then what??

well granted that you even find a cylinder that is acting up, you can diagnose the problem. Triple check the spark, get new plugs, run it hard and plugs to see what they look like. If one cylinder is soaked then you may have a spark problem or carb is dumping too much fuel(stuck float perhaps). If the plug is lighter in color than the others, then you probably have clogged jet or vacuum leak. Make sure those carb boots arent leaking, make sure the carbs are properly fitted in the boots, and make sure your airbox is on tight. Also recommend making sure your diaphrams are in good condition and you're not missing the little oring in there either. Get a multimeter and test the resistance on the coils. Get a compression tester or leakdown tester for the cylinders.

Oh yeah check the vacuum screws in the intake boots...one of them may have got shaken loose

How many miles on the engine and when is the last time you checked the valve clearances?