1995 XJ 600 URGENT HELP NEEDED!!!

So i'm a complete newbie to bike machinations. As said in the title ive got an XJ600. The last few months the bike has lost 90% of its power so I automatically think the rings are gone. Problem is I was always under the impression that Bad Rings = Exhaust Smoke. My bike NEVER smokes. Had a mechanic look at it and he said that I had a some smoke pushing through my crankcase so it was DEFINITELY rings. Now a 2nd mechanic said it could be my clutch......... So in essence :

Bike has got no power to the point where in first gear it struggles up a hill....
Bike revs high after warming up....
NO SMOKE OUT OF EXHAUST....

Can anyone shed some light on this?

Much appreciated guys.

 

How long have you owned the bike? how many miles on it?
start looking for vacuum leaks.
have you ever had the carbs cleaned/rebuilt?
when was the last time you checked the valves for proper adjustment?
look at your air filter blow it clean or replace it.
what do your spark plugs look like? when did you change them last?
How old is battery and is your charging system working properly?

if you think it is the rings do a compression test.
clutch slippage do your rpms climb and speed stay the same? when shifting hard do you hear clutch slip or see rpms go up ?

what oil are you using ? oil has to be for wet clutches standard oil will cause clutch slippage

do you have a fuel filter? could be clogged

 

mechanic should have done compression test before saying it is your rings.

your bike is a collection of systems that all need to function properly to work together for the bike to run properly.

fuel system,ignition system, charging system, motor. all need to be check.

how old is the chain and when was the last time you oiled it ? old sticking chains can cause excessive drag slowing down bike.

 

so lets start with the ignition system. ohm it out
pickup coils 304 to 456 ohms.
ignition coils primary 1.92 to 2.88 ohms secondary 9.52K to 14.28K ohms
spark plug caps 10K ohms when you have them off trim spark plug wire back about 1/4 inch

 

could be fuel starvation. have you checked the petrol tap, its vacuum operated on ,"ON" and "RES", take the petrol pipe off the tap , put tap on "PRI" position,
do you get a steady stream of fuel, if so try running on "PRI" see if it runs better. if it does then the tap needs attention.
stu

 

Sorry for the long wait. Finally did a compression test.... Readings were as such Cyl 1 = 5 Bar Cyl 2 = 1.5 Bar Cyl 3 = 1.5 Bar and Cyl 4 = 6 Bar. So i did a wet test as well and put a little oil in Cyl 2 and it jumped up to 4.5 Bar. Even though she doesnt smoke is it my rings? Or perhaps just a head gasket?

 

Have you checked the valve clearance? Very tight valve can leave you with poor compression.

 

Those are very low compression readings. Did you have the throttle fully open during the test? Are you sure the gauges are correct? If so, I would definitely check the valves first and hope they are just very tight. If that doesn’t fix it I would say that your problem is bad rings and/or burnt valves.

Semper Fi—are you a Marine?

 

jump in readings is more indicitive of rings than valves. You still should do a shim clearance check to start with

https://www.xjbikes.com/forums/threads/the-information-overload-hour.27544/

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In order to further analyze a low-compression condition, you should squirt a small amount of engine oil into the suspect cylinders (about a teaspoon), crank the engine over for a few revolutions to spread the oil about, and then re-test those cylinders.

g) if the compression pressures RISE by a large amount after the infusion of oil, then this typically means that the pistons, piston rings, or cylinder walls are damaged or worn in some way(s). However, be aware that if you introduced a significant amount of oil into a cylinder (1 teaspoon or more) when conducting this test, a small rise in pressure may occur, and it may instead mean that your valves are the problem, since the introduction of that much oil in a small cylinder will naturally cause the compression to rise.

h) if the compression pressures do NOT rise after the infusion of oil, then this typically means that the valve seats or faces are worn, or a valve is hanging up within its guide, or your valve clearances are way too small.

i) if two adjacent cylinders (cylinders 1 and 2, or cylinders 3 and 4) have low compression, and the oil treatment produces no greater pressures, this points to a damaged cylinder head gasket, warped head, etc. .................