FJ does not want to run right

[Pat Conlon]

Did you get a shop dyno for those numbers?

[RPM - Robert]

Yup, they make us do compliance tests after winning.

I also had a brake problem on a Saturday and ended up spending several hours on the dyno Sunday while Ryan was racing, adjusting jets, needles, fuel, diaphragm springs, muffler, etc etc. Changes. Made about 20 different hits. To find the best combo.

[fj1289]

Y'all got the dyno?!   Awesome!!!!! 

[Pat Conlon]

Tell us more about your dyno....

Can I bring my bike?

[RPM - Robert]

Sorry, I mis read your question about the dyno, or shop dyno.

No, unfortunately, we still don't have a dyno. They are at the track. I paid for the hours of time for my car. The dyno guy was kind enough to let me tune my stuff while leaving the car up there (He was an old motorcycle guy at heart and just kept telling the rest of the cars that pulled up that he didn't have time) The compliance tests, after the races, are paid for by the sanctioning body.

[fj1289]

Robert - those are the FJ/XJR carbs on the Busa motors for that class?

What RPMs are they making power at with the carbs?  Wondering how much the carbs choke it on top end?

[RPM - Robert]

Correct, they are the FJ carbs. They peak about 7500 and fall flat on their face at 8k

[gdfj12]

....I am considering a larger one with all stainless steel construction for bigger parts and possibly big enough to fit the bank of carbs together.
George D

Hey George, which one are you considering?
Last time I looked into a ultrasound unit with a tub large enough to hold a rack of FJ carbs, the increased cost was considerable. For as often as I need to use it, it was not practical.
Disassembling the carbs off the rack is no big deal for me. With them disassembled, I can then replace the o rings on the fuel inlet T's

Although now it's even better....I store my FJ's with VP C-9 race fuel.....never a worry about plugged carbs again.

Cheers mate

Pat,

I've been looking for a while, I have one good set of carbs on my '89 and 2-4 sets of carbs off of 1200's and 1100's that are in need of cleaning and rebuilding. I'm trying to finish up some updates/repairs/mods to my '89 so that I can start on the '86 I got from Calvin that needs a bit of TLC/upgrades/etc. My Modifiers Anonymous membership is NOT in jeopardy! ;^)

After you and Robert mentioned the o-rings in between the carbs I realize that it is wiser to totally disassemble them. But the bigger 30L tank will clean all of the parts in one session as well as other larger parts like case covers, oil pans and especially sprocket covers that won't fit in the 2.5L cleaner. I also seem to have a 'problem' with 'collecting' used Victorinox, Leatherman and other pocket knives and multi-tools that need cleaning off of fleabay. I found several examples withe decent reviews on Amazon for between $250-400. So, one of them is in my future.

I would also like to test the combination of the ultrasonic cleaner with a rust remover liquid like Evap-O-Rust. I just may have to line the tank to protect the stainless though.


George D

[chrism40]

Hi Chris,

Good to see that it has definitely been narrowed down to the carbs.

I have used this Ultrasonic cleaner in the past. It does a great job.

https://www.harborfreight.com/25-liter-ultrasonic-cleaner-63256.html


Fred

I hope you have mentioned and talked your friend with the pristine Blue 89 FJ into attending the Vintage Yamaha Rally??

Hey Fred.  You will know the owner of the blue bike when you see him. He goes every year. He is still cleaning  the gas tank getting it ready for sealing. It "just" needs the engine bare aluminum and the peg stand assembly polished to look nearly new. That is a lot of detail work and very time intensive, but the owner excels at that kind of stuff.  This year we could have over 10 FJs there.

[aviationfred]

Hi Chris,

Good to see that it has definitely been narrowed down to the carbs.

I have used this Ultrasonic cleaner in the past. It does a great job.

https://www.harborfreight.com/25-liter-ultrasonic-cleaner-63256.html


Fred

I hope you have mentioned and talked your friend with the pristine Blue 89 FJ into attending the Vintage Yamaha Rally??

This year we could have over 10 FJs there.

Just between you and I, we will have between 6 to 8. I plan on bringing 3.


Fred