Quote from: teazer on October 12, 2021, 03:13:08 PM
fJ6 were used in RD400E and F in Australia and I think Canada, so you could check the parts list and see if your dealer can get a pair or see if they are available in either of those countries as a Yamaha part.
They are leaner than say 5L1 used in C/D models and richer that 5I4 used in RD350s. The closest Mikuni needle I found is 5DP7 which is a little leaner and may require larger needle jets or different air jets to get the fuel slope right.
You could measure your OEM needles every 5mm and compare the dimensions to keyster to see how close they are. To do that you can use an optical comparitor or just take a piece of paper and mark a line every 5mm. Then make sure to tart at the very top in the same place and measure the diameters.
A simpler but less numeric way is to use a set of vernier/digital calipers and close them most of the way up on a needle and then slip the other needle in beside it. If the second needle is smaller diameter it will slide further through the jaws and if it's fatter it will sit higher. It's fiddly but easy to see if one needle is thicker or thinner than another at any point along its length.
it appears that http://hodaka-parts.com/ finally has them available i just ordered one.