Quote from: 86FJNJ on August 18, 2025, 10:31:51 AMI have an 86FJ I rehabbed, it now runs very well but I have noticed if I get the RPM's high enough in first gear it sometimes goes into neutral not 2nd gear. Had an odd issued when downshifting from 3rd to 2nd as well. Also if I really lay into it it feels like the clutch can't hold the power for a second or so...for me it's not a big issue I just ride normal and it doesn't really happen often. For me it's not a bike I rip around on, it's 39yo so I just enjoy it for what it is, a vintage bike...if I wanted to really rip around on a mean performance machine I could pick up something newer but used for not much money.

Makes sense to me.

I have an 86FJ I rehabbed, it now runs very well but I have noticed if I get the RPM's high enough in first gear it sometimes goes into neutral not 2nd gear. Had an odd issued when downshifting from 3rd to 2nd as well. Also if I really lay into it it feels like the clutch can't hold the power for a second or so...for me it's not a big issue I just ride normal and it doesn't really happen often. For me it's not a bike I rip around on, it's 39yo so I just enjoy it for what it is, a vintage bike...if I wanted to really rip around on a mean performance machine I could pick up something newer but used for not much money.

Sure, you can wait and see what happens, just don't be surprised.
Depending on how long you plan to keep your bike, if the 2nd gear problem has never been addressed, sooner or later you need to consider it.
Take a quick read:
https://fjowners.com/index.php?topic=666.0

RPM has all the goodies you need
Shift forks and back cut gears:
 http://www.rpmracingca.com/products.asp?cat=39&filter=Shift%20fork

Quote from: Pat Conlon on August 17, 2025, 07:29:18 PMThe biggest modification I recommend on early FJ's is to replace your transmission shift forks with late model FJ forks and back cut the engagement dogs on 2nd gear.

Thanks Pat, good info.  Regarding the shift forks/dogs for the 2nd gear, replacing the forks and modifying the engagement dogs is a lot of work and effort.  Other than a test drive, I haven't really ridden the bike yet.  During the test drive, I did not notice any issue with the 2nd gear.  I'll give it more power and put more load on the 2nd gear the next time I ride the bike.  But if it turns out that the 2nd gear works fine, shouldn't I just wait for the issue to occur before tearing into the engine/transmission to fix something that isn't a problem (yet)?  Or am I missing something?   

Yep, DID ZVMx is my favorite.

I would be interested if it the correct upper.

DID chain for me too with JT sprockets.
Sunstar sprockets are alright though, got them on my Tiger 800xc.
Never skimp on quality chains for the FJ.

Quote from: MarioR on August 15, 2025, 12:39:27 PMAny pictures?

Try to post some tomorrow.

 What else is needed with 1188 Wiseco piston kit?

Nothing is really "needed" the displacement is close to the stock 1200cc that you could run the stock exhaust and airbox and carb jetting and everything would be fine.

However, a favorite saying around here is:
 Old FJ's don't die....because we modify!

Stock FJ jetting on the US models  is lean due to EPA regulations so we fatten things up for a cooler running engine.
From #37.5 pilot jets up to #40.0 or #42.5 pilots.
Shim the needle 1/2 step
From #110 main jets to 112.5 or 115.0 or even 117.5 or #120.0

The biggest modification I recommend on early FJ's is to replace your transmission shift forks with late model FJ forks and back cut the engagement dogs on 2nd gear.

An aftermarket header and UniPods are just frosting on the cake.
UniPods are especially desirable because time will come when you have to R/R your carbs and the UniPods will make the job easier.

A good tune with these mods will get you around 120rwhp.

Cheers

Pat

Ok just asking because the fj1200 jugs say 1188cc on them but people make them 1250cc or even larger.

Do you know if the carbs were changed from the FJ1100 carbs to the FJ1200 carbs? Do you know what jet sizes are in the carbs?

Buy these air filters to flow more air in. They delete the stock airbox. You'll need to buy two. But you will need to modify the carbs to run these so you should decide what you want to change on the exhaust too so the group can make suggestions on carb jetting.

https://www.rpmracingca.com/proddetail.asp?prod=Carb%3ARPMPod&cat=24

Plus the filter oil

https://www.rpmracingca.com/proddetail.asp?prod=Carb%3Afilterspray&cat=24

What state are you in? Carb jetting varies by state (elevation, temp, humidity etc)