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carbs

Posted: Thu Apr 05, 2012 11:55 am
by floridafzr600
is it typical for fzr carbs to two different types of main jets?

Re: carbs

Posted: Thu Apr 05, 2012 11:56 am
by floridafzr600
sorry mine has 108 on outside and 112 djs on the middle 2

Re: carbs

Posted: Thu Apr 05, 2012 12:38 pm
by blensen
I don't know if it's exactly common, but it's not unheard of. The middle two cylinders are jetted richer because they typically run hotter than the outer two cylinders. Not usually a big problem on liquid cooled bikes, but if it pulls hard I wouldn't worry too much about it.

Re: carbs

Posted: Thu Apr 05, 2012 4:18 pm
by DonTZ125
That's backwards, at least for liquid cooled engines - I can see air-cooled mills using the fuel to help cool the head and piston.

Where cooling isn't a problem, the center cylinders use SMALLER main jets, as the hotter intake runners result in a less-dense air charge.

Re: carbs

Posted: Thu Apr 05, 2012 7:34 pm
by floridafzr600
alright i was just wondering but the backwards issue could be my i am hitting a brick wall at 7k for a second or two

Re: carbs

Posted: Thu Apr 05, 2012 8:55 pm
by DonTZ125
What do your plugs look like? Before I suggest dropping the centers to 105s, let's make sure you aren't already dangerously lean!

Check your battery voltage at 5k - a failed-low VRR can't fully charge the coils as the revs come up.

Re: carbs

Posted: Sat Apr 07, 2012 8:04 pm
by floridafzr600
its rich its spitting fuel a little bit now and i just upgraded to a r6 vr im replacing plugs tomorrow

Re: carbs

Posted: Sat Apr 07, 2012 8:08 pm
by DonTZ125
Unfortunately, the R6 VRRs fail too - I've heard more tales of 'failed low' than 'failed high', but it's still annoying. I suggest you check your 5k voltage.

If your #2-3 plugs are black and wet, look at your 1-4 plugs. If they're tan and happy, drop to #105 mains in the center carbs.