I had my R reg xj 600 N restricted 18 months ago, today whilst fitting a new choke cable I got a bit curious.

My understanding is that the official Yamaha restrictor kit was a set of washers that sat between the Carb and the top of the engine inside the rubber seals, or is it a complete replacement set of the rubber seals?

If it is the later then fine, if it is separate washers then I paid £200 for a useless piece of paper and I have been riding illegally for 18 months.

There are 3 types of restrictor for the XJ,

the first one shown here is a 'Washer' type plate that reduces the amount of air/fuel,4 of these.

or this one which acts like a 'stop' on the carb slides, 4 of these

and this type sits under the intake rubbers on top of the manifold, also 4 of these

so get the tank off and the air-box and start delving, be very carefull with the rubbers (oooh eeer Missus)

hope this helps

I assumed it would be the last one, but looking at the picture they are not there, neither is the second one. I will have a look for the first type tomorrow.

Thanks for the reply.

I have checked this morning, no washer plate on the bottom of the manifold, and no washers in the rubbers at the top of the manifold.

The only thing left is the carb sliders, I am struggling to understand where these are, do they restrict the throttle piston from moving back? How do I find them?

Thanks.

It tells you on the certificate what type of restrictor is used.

Well it does on mine - blade.