ah yes I misunderstood. Congrats on your new FJ post some photos and updates for us to see.

The stumble was when I started to accelerate from a stop.  As I went through the 2k rpm range it sputtered and hesitated just a bit, then when I hit 3k it took off.  It was enough to keep me from wanting to ride in that rpm range. After I fixed the stumble I loved every speed and rpm range the bike had.

I'm not sure if you understood my post.  I'm not experiencing this problem now.  I solved it a year ago, and was just talking about the solution.  Carbs were thoroughly cleaned, no vacuum leaks.

I sold the bike to a young kid.  About 6 months later I saw the same bike for sale again on Marketplace for a fraction of what he bought it for cause it quit running.  I bought it back from him, and discovered that the electric plug going to the stator had melted and it wasn't charging.  Unfortunately, he had taken my nearly perfect beautiful bike and had used it as a dirt bike.  When I got it back it was covered in mud and the tank had a nice dent in it.  The back tire was nearly bald, which meant he spent a lot of time doing standing burnouts.  No respect for the vintage bikes. I cleaned it up as best I could, hardwired the stator plug and sold it again.     

Quote from: Karl321 on Today at 01:19:05 PMThe pods you recommended are out of stock, but I'll be emailed when they available again.  Until then, I'll try to make a set of K&N pods that I already have work.
 

They're in stock just got another batch in today. The red ones are gone they are all black now.

I didn't have any issues with stumbling off idle with my FJ1200 but that's because this group directed me in the right direction to get my set up as close as possible from the start. I ended up having a hanging idle which went away by increasing the pilot jet size and switching to HSR needles/springs.

The FJ carbs are CV carbs, are the XS1100 carbs also CV carbs? How bad is the stumble off idle, is it like just a second or two or is it just bad idle below 3,000 rpm? Were the carbs thoroughly cleaned to ensure all idle passages are clean? Have you checked for a vacuum leak near you intake rubbers?

Thanks for the info in your reply.

I'm in Cincinnati.  I ride around southern Ohio, Kentucky and Indiana.  Elevation is between 400ft and 1500ft.  If I ride any farther than that, it will probably be on my Valkyrie.

The pods you recommended are out of stock, but I'll be emailed when they available again.  Until then, I'll try to make a set of K&N pods that I already have work.

The All Balls rebuild kit I have coming includes adjustable needles to replace my fixed needles, so I'll make the adjustment you recommend.

I just pulled the carbs a few days ago, and was shocked by how varnished and rusty and locked up they were.  Worst carbs I've run into so far (I've only rebuilt maybe 10 carbs so far in the past several years.) But after PB Blasting them and a hot ultra sonic soak, I got everything freed up.  The carb bodies seem just fine.  The corrosion seems to just be to the brass that's all being replaced. 

I assume you haven't experienced the same stumbling issue when using pods that I described with my XS1100? 

The Yamaha ignition cover and the other side crank cover we have new stock, as well as the clutch cover outer ring and the center part that says Yamaha.

The edges of the fins on the block and head were always raw aluminum. You can tape the frame off and get in there with some small scotch brite wheels in between the fins and scotch bright whatever you want to paint after a good ole pressure washing to get the big gunk off. After you spray it you can take a sanded block and clean up the edges of the fins to be raw aluminum like they should. Working up to a super fine sand paper so it doesn't look all gouged up.

Quote from: STLanduyt on February 11, 2026, 07:44:30 PMI had initially thought of painting the pipes, but am now thinking of leaving them in their current state.  Any thoughts or experiences out there on just leaving the pipes alone?

Steve

Jet-Hot is a company I used to coat my header and I have been astounded by the product.
Their 2K product has a black crinkle finish on the outside, not sure it is not lifetime guaranteed, but it is tough. It does not damage by road debris and it clean up easily.
The inside was coated in a ceramic heat whatever substance, see pic #2.
The pipe is cool to the touch within moments of stopping, it works that well.
That heat has to go somewhere, I am not sure of the positives or negatives, I'll leave that to the experts here.
Bike runs great, pipe looks great, I'm happy, it was about $250 with shipping back in 2019 and worth every penny.
Look at pic #1, that's a lot of miles and several years ago.
Options are good.


https://www.jet-hot.com/offroad

Most of that looks topical like it would clean off with a sponge and some hot water with dawn dish soap. Then let it dry and spray it down with some foamy engine degreaser. Should look decently good after that. I'd suggest upgrading your oil filter to the RPM spin on oil filter setup. Better look and easier oil changes compared to that rusted stock oil filter bolt you have.

https://www.rpmracingca.com/proddetail.asp?prod=spinonfilteradapter&cat=39

The sprocket cover can be sanded down to raw aluminum and then painted with VHT Gloss black engine paint and cured in front of a space heater...will look brand new after that, which is what I did to mine.

Do yourself a favor and buy these air filters, many of us with FJ's run these.
https://www.rpmracingca.com/proddetail.asp?prod=Carb%3ARPMPod&cat=39

When using these pod filters you will need to shim your needle to dump a little more fuel into the mid range.
https://www.rpmracingca.com/proddetail.asp?prod=Carb%3AMainNeedleShim&cat=39

Your 42.5 pilots and 117.5 main jet seem like a good starting point. What country or USA state are you in? What elevation? Jet sizing can vary by location. I'm in NJ and running 42.5 pilots with 120 mains, 155 air bleed and HSR needles with Dyna springs with an open 4-2 exhaust.

This is a link to my restoration, PO had bike sit 15 years before I got it. I list all the parts I used which may be of interest to you.
https://fjowners.com/index.php?topic=21474.0

I'm on this site cause I just bought my first FJ1200.  A '91 nonrunning bike in nice shape that sat for 10 years.  So I'm just starting the project and learning a lot here.  Thanks to everyone in advance for all the great information.

My first bike back in the 90's as a poor college student was an XS650 Special. I then had an 850 Special, then several 1100 Specials.  I quit riding for 25 years, then got divorced and started buying bikes again.  I keep finding nice old Yamaha XS1100 Standards and Specials in the back of garages that just need a new battery, a carb clean, brakes and tires, Euro bars to replace those horrible ape hangers, and an afternoon with some NevrDull and Colonel Brassy, and I can flip it and fund the next bike project. (And maybe cover an alimony payment).

One of the bikes I bought last year came with a 4 into 1 Kerker exhaust and air pods.  The PO said he never got it running right way back when, so he parked it and forgot about it.  I rebuilt the carbs with the right jetting, and got it running almost perfect.  The only problem I was having was a little bit of stumbling off of idle at low rpms. When I got over 3k it cleared up. 

The general consensus with a lot of the XS1100 guys is that pods aren't worth the hassle.  They're fraught with tuning problems, including the stumbling I was experiencing. As explained to me, the air turbulence created by the pods causes problem as it enters the carbs. A stock air box smoothed the air flow out before entering the carbs.

To try to correct this, I added 2" tubes between the pods and the carbs. The idea was to give the air flow a chance to settle down before entering the carbs.  I cut down plastic connectors from a shop vac hose that happened to be exactly the right diameter. (Always on a budget) 

This worked beautifully. The result was smooth power from idle to WOT at all rpm's. Right or wrong, I believed that I had found the miracle cure for pod problems. Or at least my particular pod problems.   

So my obvious question is if anyone else has tried something like this on their FJ1200?  Or has anyone had this same stumbling problem with pods off idle, or at any other rpm range? 

My FJ project bike has a 4 into 1 Vance and Hines exhaust and the stock air box.  I'm going to replace the box with pods both with and without my extension tubes and see what happens.

I've got 42.5 pilots and 117.5 main jets on order from JetsRUs.com, along with an All Balls rebuild kit with adjustable needles.