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General Category => Yamaha FJ1100 / FJ1200 Running Problems => Topic started by: JohnnyTheCraneGuy on May 11, 2025, 11:23:21 AM

Title: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 11, 2025, 11:23:21 AM
Well guys, looks like it might be time for some more rework.

Yesterday I went out for a ride and within about 5 miles I had the same issue happen to me 4 times before getting back home.

When I was in 2nd gear at about 4-6k rpm and I rolled off the throttle, not under heavy accel either, on decel it'll slip outta gear and give me a false neutral.

My guess is maybe a shift fork might've bit the dust.

Either way I guess it's time to split the case on 1100 and see what I can scavenge from that.

FJ1289 mentioned that while I'm in there I could double up on my clutch springs, and swap the judder spring for another friction disc.
Title: Re: False Neutral on Decel
Post by: racerrad8 on May 11, 2025, 11:58:54 AM
Before open case surgery, you might try the RPM shift kit. It has a roller detent which allows the use of a heavier spring. This keeps the shift barrle/forks in position much better.

Randy - RPM


https://www.rpmracingca.com/proddetail.asp?prod=RPMRollerShiftkit
Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 11, 2025, 02:04:53 PM
Will definitely give this a look!
Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 24, 2025, 08:31:49 PM
HOLY SHIT BOYS ARE WE BACK IN BUSINESS OR WHAT
Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 24, 2025, 08:54:43 PM
I believe my issue was in the little arm that grabs the pegs on the shift drum. The spring had seen better days it seemed.
Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 24, 2025, 09:16:44 PM
I ended up pulling the shift shaft from the 1100 and transplanted that over.

Also got the detent kit installed.

Another hurdle I had to jump over was running through the clutch basket and seeing what I could salvage from both to squeeze a few more miles out of them, before I go swap over to the barnett eventually  :good2:

On the 1200 the front narrow disc that rides against the pressure plate had no friction material left!  :negative:
Not too mention the surface of the pressure plate was now scored pretty good, granted nothing you cant polish or surface off. The steels weren't warped, and they were all close enough to 2.0mm, although not bad there was a few hotspots scattered throughout. I will say the boss did still have the factory wire that retains the rear narrow disc.

The 1100, even though she has more miles, PO did some maintenance! The frictions were slightly thicker at 2.8mm while the 12's were at about 2.6mm. Also the steels were new! There was no discoloring or hotspots through any of them, and the wire was removed. The PO didn't do the disc swap though, as there was a narrow in the rear.

Stack height came in at 38.5mm.

Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 24, 2025, 09:39:56 PM
I also stacked clutch springs! I will say it was a little tricky tuning/torqueing the spring bolts, WHO THE FUCK HAS A TORQUE WRENCH that does sub 10ft-lbs  :dash2:

I picked one up at Harbor Freight, so got that figured out.

All and all the difference was absolutely night and day for me!  :yes:













Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 24, 2025, 09:51:18 PM
I will say too that in all of that work I had unfortunately, but thankfully developed, and found another issue. :bomb:

After bolting everything together and filling her up the first time I fired her up on the center stand with the wheel in the air. Confirmed everything spun and stopped the way it should. dropped her down, went up the driveway and BOOM she started clunking and screaming at me with the lever out.

Rolled back into the garage. Ah well, at the time it was day 1 of the project, not anymore!  :morning2:

I assumed it was maybe uneven/inadequate torque on the clutch spring bolts?

My crazy ass spent a lot of time focusing my troubleshooting there, and it sucks but I lost a good amount of time there.

I'll save you guys the drama but it ended up being something that would've definitely left me stranded lol. The front sprocket ended up getting sheared by the output/countershaft  :biggrin:
Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 24, 2025, 09:59:40 PM
Thankfully I still had a stock front sprocket so we're still trucking!
Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 24, 2025, 10:08:46 PM
I will say too thank you Randy for the detent suggestion, you definitely saved me here from dropping the motor again and splitting cases. I owe you and your boys a beer one of these days!
Title: Re: False Neutral on Decel
Post by: Waiex191 on May 25, 2025, 08:23:13 AM
Quote from: JohnnyTheCraneGuy on May 24, 2025, 09:39:56 PMWHO THE FUCK HAS A TORQUE WRENCH that does sub 10ft-lbs
I thought everyone does?  My in-lb wrench goes down to 25 in-lb.
The purpose of the hobby is to buy tools.
Title: Re: False Neutral on Decel
Post by: JohnnyTheCraneGuy on May 25, 2025, 12:33:11 PM
Yeah a 1/4 drive torque wrench was a new one for me, never had a use in the field for me, and everything I could've used it for at home I got away with by hand. Didn't want to mess up with the spring balance and tension though, not worth it.

Like you said, buy more tools!  :hi:

Can't wait to show the other techs my new toy  :rofl2: