Fuel screw trouble

[cnap504]

I have ruined one of my 1980 XS 1100 fuel screws and need a replacement. I’ve looked at online sources and what looks to be the correct part the fitment chart says otherwise.
Are all Mikuni BS34 fuel screws the same? And I can’t find the original part on a usually reliable microfiche source. Any help here would be appreciated

[DiverRay]

What are you calling a fuel screw? Do you want the idle mixture screw? A picture may help, the carb with location?
To post a picture use the Upload Attachments button below the smilies.

[cnap504]

Yes the idle mixture screw. Thanks

[bikerphil]

This is the 80-82 screw, the 78-79 is different.

https://www.mikesxs.net/yamaha-xs650...-14105-00.html

[cnap504]

That does look like it and I have seen them online but the problem I have is they don’t have the XS1100 listed in the fitment chart. Also went to ronniesmicrofiche and they do not even show the part, I was thinking maybe because it was the first years of “plugged” idle fuel screws. Just wanted to cross reference the oem part number but can’t find it and as I mentioned the “fuel” screws I have found for Yamaha Mikuni BS 34’s reference several model but never the 1100

[cnap504]

[bikerphil]

The one in the link is the correct one, for the BS-34 type 3. Is the screw stripped or the carb body?

[cnap504]

The screw is damaged beyond repair

Still curious what the oem part # is
12R-14105-00-00
11J-14105-00-00
or none of the above, I’d rather buy original equipment than aftermarket when I can.

[DiverRay]

OEM part number will change over time. You would need to start with an '81 parts fitch, and go up about every five to ten years to follow it. You could also go to your local Yamaha dealer and have them look it up. As you know the carb model, BS-34 Type 3, they can find it. The one from Mikes works well, and as that is NOT a jet or needle main valve, there are no problems with the part. Also, it comes with the small parts that MUST be changed at the same time to keep the carb working correctly. The dealer will want about 5 times the price for all the parts, and may take a month or two getting them.

[cajun31]

go on Ebay and do a search for 1980 idle mixture screw and you can find full sets of four of them for a very reasonable price.

[FJ111200]

The screw is damaged beyond repair

Still curious what the oem part # is
12R-14105-00-00
11J-14105-00-00
or none of the above, I’d rather buy original equipment than aftermarket when I can.

I used the 12R1410500 from the FJ1200 in a set of XJ1100 Mikuni 34mm i was repairing. Same things for the XS1100 81 LH Midnight Special. PILOT SCREW SET for FJ1200 1986 1TX ENGLAND 261TX-310E2 - order at CMSNL

[cajun31]

These will fit too. 4X For Yamaha XV250 FZR750 XV750 XV1100 FJ1200 Fuel Air Mixture Screw Set | eBay

[cnap504]

Thanks everyone for the recommendations. I found a Yamaha oem idle fuel screw part number 11J-14105-00-00 it’s the one I needed for the Mikuni BST 34 type III carbs on my 1980 XS1100 Special. There are aftermarket fuel screws available as well. Thanks again

[cnap504]

I got the carbs back together and installed them and it now has been started and run for the first time in almost fifteen years. I did all the necessary maintenance and repair a 15 year non running bike would need, and as soon as I finish the brake fluid bleeding this bike will be ready for a test ride.
Excited to ride a 41 year old classic

[DiverRay]

Watch for sticking brake calipers!!!! If you did not pull them apart, I WOULD do so BEFORE the first ride. The caliper is aluminum and will stop the piston from returning after one or two times. If you have gone through them, then bleed and enjoy the ride!