Typical front fork "clunk" sound.
Typical long warm up due to lean stock carburetors.
Stock shocks are dead in the 15-18,000 mile range.
Ball bearings used for head bearings wear out. Replaced with tapered roller bearing types.
Stock seat rear cowl cracks if the underside of the seat is not supported with extra foam/rags/etc when a passenger rides regularly.
Tanks usually have to be cleaned coated since there is an area by the seat which is lower than the fuel petcock, and it gathers water and munge and could rust out.
One of the bikes had the wrong petcock/fuel tap on the tank, probably due to the dealer cleaning fuel tanks and rebuilding petcocks from the leftover bikes during the 1980's.
I own two of this model. One my father bought new as a leftover in 1987, and another he bought used from a friend in 1993 (great deal) and put in storage. My father later gave me #2 in 1998, which I refreshed 2nd in 2000. Sadly my father passed away in 2005, so I now have the XJ which he bought new in 1987.
Typical modifications for both: K&N oem airfilters, stainless brake lines, head bearings, after market rear shocks (Konis, which are now made by Ikon), progressive front springs in modified front forks (drilled the internal holes out a little and put heavier oil in- 15w or 20w versus 10w stock), small wind screens, 1st RJ had wider handle bars installed.
Oil coolers: one is from Lockhart and the other was from a US spec XJ650 Turbo (difficult, but doable conversion especially since the Turbo cooler is taller than the stock European only non-Turbo oil cooler, as the mounting points were slightly different).
Want to get an oil filter conversion kits for both of my XJ's to use automotive type type spin-on oil filters in place of the stock replaceable element. Someone is making and selling these via the xj owners list.
Great XJ-owners list at micapeak who publish a near free-cost great CD set of service and other info for the XJ series.
An excellent review of a truly amazing bike. I bought my first Seca new in 1984 and maintained it myself; mods were limited to Progressive fork springs w/10w Kalgard and 1" preload spacers as well as a set of Fox rear shocks and Barnett clutch springs.
Did not have a single failure until 89,000 miles were on the odometer; in the course of three days the original alternator brushes needed replacement, the original petcock needed a rebuild and the original clutch cable broke and was replaced.
At 122,000 miles, I did an in-bike cam chain replacement and promptly did a 2,000 mile loop through the western states. The next week the speedo gave up the ghost and was replaced.
Finally parked it in my garage with 153,000 miles when a Seca 650 with 40,000 miles on it came up for sale for $400 in 1995. Only 39 units separated it from my first Seca and it has proven to be every bit as reliable.
In conclusion, if you find one well maintained and can live without fuel injection, wide radial tires and fully adjustable suspension, you will have fun riding for years to come.
Nik Foster.
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