Category Archives: xj650

Repairs to the Ratbike

I have had to take my bike off the road for a few weeks as it wasn’t running very well. I narrowed it down to two things, dirty carbys and coils breaking down under high load and when they got hot.
I spent nearly six hours cleaning the carbs, pulling them right down and scrubbing with a toothbrush, I have ordered a set of carby rebuild kits with new gaskets, needles, seats and washers. As well as the kits I also have a reusable/washable K&N Air filter element coming for the bike that drops in to the existing air box.
I lubed all the cables throttle, choke and clutch with silicone oil lubricant as well as spending some time tidying up some wiring on the bike re-wrapping it with tape and re-routing it away from sharp edges as I was a bit slack when I first put the wiring in for the spotlight and two way radio. I also have to add a fuse to it as I didn’t have one which is a fire hazard.
I am also going to give it an oil change and new oil filter while it is off the road as well as new fuel lines and vacuum lines. I will be using 8mm High Performance coil leads and new titanium plugs to go with the high performance coils.
I got on to eBay and purchased a pair of Dynatek DC1-1 coils designed for electronic ignition as my bike is pointless. The coils are 3 ohms and put out a 35000 volt spark on the secondary side. This will mean better cold starting and better burn of the fuel. The coils also take standard spark plug leads unlike most motorbike coils that have the leads moulded in to the case.
I had to do some chopping of brackets that held the original coils and also reroute some cables and reposition the flasher can and cut out the bracket for that as well. I mounted the coils across the bike instead of along the frame as the are larger then the originals and wouldn’t fit in the same place.
Personally I think it has come up well, now to just wait for some of the parts to arrive from the USA as well as get some bits from the local auto shop and I am right to go
Coils shown mounted inside the frame from the left of the bike
Coils from right, if you look under the edge of the frame you can see where the leads plug in just under the writing on the frame showing which coil runs to which cylinder


Coils from top right, you can see an aluminium plate running across the mounting points, this is the earth strap for the secondary earth to the engine, cable comes in to coil on the left of photo and then the plate connects both coils together