Info Important Notice Corrected - FZR250 Mikuni

Hi All,
Referring to Joker’s float valve seat o-rings that he mentioned in his thread. That suffered compression damage.

This is my fault. Some time ago I reduced the ID on these o-rings in response to what was believed at the time to be a problem of these o-rings being too loose on some FZR250’s.
See https://2fiftycc.com/index.php?threads/important-notice-mikuni-bdst-bst-carburettors.1876/

The road to hell being paved with good intentions and all, this was subsequently shown to be actually caused by worn needles and emulsion tubes. These o-rings are exposed to fuel all the time and all elastomers swell when exposed to fuel. Yamaha planned for this by making the ID of the o-ring looser than normal. The OD of the o-ring is sufficient to seal when pressed into the slightly tapered recess and the relaxed clearance on the ID is able to cater for the expansion when the swelling occurs. I have reverted to the exact OEM dimensions and supply new o-rings of the correct dimension to anyone that needs them. Starting with Joker of course. Please contact us directly if you require a new set and please accept my apologies for any problems this has caused you.
Cheers
Blair