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General Category => Modifications => Topic started by: JohnnyTheCraneGuy on July 30, 2025, 09:26:47 PM

Title: Keihin Flat Slides
Post by: JohnnyTheCraneGuy on July 30, 2025, 09:26:47 PM
Does anyone have any recommendations with Keihins? I'm looking at acquiring a pair that I could use when I swap to the bigger pistons and maybe cams. Another reason too is I'vw seen them come up on facebook here and there for a Y\FZR750, a kehins FCR39. But from what FJ1289 was telling me, those are set up for downdraft rather than side. Another was listed as a CR31-3051 for hondas CBFs, I messaged the owner and he said they were down draft as well, so I am scratching my head a little bit here.

If anyone has experience with this and could share the specific models I would need, that would be a huge help for me.
Title: Re: Keihin Flat Slides
Post by: red on July 31, 2025, 07:38:45 AM
Johnny,

Can't help with specifics, but I would send Keihin an email direct, and see what they advise.  Website:
Keihin (https://www.keihin-fcr.com/index.php?route=information/contact)
Title: Re: Keihin Flat Slides
Post by: JohnnyTheCraneGuy on July 31, 2025, 09:16:43 AM
Right on Red, thank you sir!
Title: Re: Keihin Flat Slides
Post by: Pat Conlon on July 31, 2025, 09:33:15 AM
77-85-77 is the carb spacing you want to fit our FJ's.

The Mikuni TMR36 or 38's roller flat slides have a choke for cold starts
https://www.bikeside.de/MIKUNI-TMR38-flat-slide-carburetor-for-all-KAWASAKI-GPZ-900-R-GPZ-1000-RX-and-YAMAHA-FJ1100-1200

(https://www.bikeside.de/media/image/product/7452/lg/mikuni-tmr38-flachschiebervergaser-fuer-alle-kawasaki-gpz-900-r-gpz-1000-rx-und-yamaha-fj1100-1200.webp)

The more expensive Keihin FCR39 roller flat slides do not have a choke.
https://www.bikeside.de/KEIHIN-FCR39-flat-slide-carburetor-for-all-GPZ-900-R-GPZ-1000-RX-ZR-1100-Zephyr-and-FJ-1100-FJ-1200

(https://www.bikeside.de/media/image/product/7431/lg/keihin-fcr39-flachschiebervergaser-fuer-alle-gpz-900-r-gpz-1000-rx-zr-1100-zephyr-und-fj-1100-fj-1200.jpg)