Full revs!!

Hi there,
My 1st post so be gentle. I'm an old XV750 owner but have just purchased 2 '81 model XJ650's to not so much restore but to modify and have a bit of fun with. Things WERE going great, awesome bikes to work on, but I have a bike that since I have put it back together as soon as it fires up just goes straight to full throttle?? I have tried the usual mechanical issues like loosening idle screw right off, checking for proper operation of throttle cable (I even disconnected it to rule it out). I have to hit the kill switch to stop it from throwing a piston at me it revs so hard. The obvious change I have made is I have put pod filters on. I can't imaging an air leak causing it to rev so high. I have never connected the choke back up?? When I turn the throttle neither butterflies or slide move, is this correct?? Are they vacuum operated?? Thanking you in advance...

 

Welcome! Yes they are vacuum operated CV carbs.

Here's some homework for you,


http://xjbikes.com/Forums/viewtopic/t=14692.html


http://www.xjbikes.com/Forums/viewtopic ... vving.html

http://www.xjbikes.com/Forums/viewtopic ... vving.html

 

Thanks heaps.

 

To qualify , yes they are vacuum operated,the vacuum moves the slides when running, but the butterflies should move with the throttle movement running or not, cheers , Murray

 

Check the intake boot clamps to make sure one isn't holding the throttle open.
Also check where the cable sits in at the carbs, I've had one that was sitting on top of it and not in where it should be.