Just bought 98 model. It runs perfectly....rev it up i hear nothing. However, in gear going down road you can hear a knock when up in rpms. Please tell me I didn't just by one with engine about to let go
T off the oil pressure port you should see 70# at 5k. Let us know what it reads at idle first should be at least 10# when warmed up.
Thank you...I'll have to get a pressure gauge I guess. I do hear a slight chain noise I believe. Tensioner maybe. I read on cbr bikes you can rotate a screw in the tensioner to tighten? Is that correct? This was a theft recovery. Engine sounded smooth when started and ran. But when ridden I hear that knock and slight rattle. I do understand these motors are bulletproof and also I'm reading the knock a bit
I'll try to get a pressure gauge soon. I'll have to look at this port you talk about . Location?
Thior, a worn out cam chain tensioner (cct) will rattle like marbles in a can, especially loud at 3-4000 rpm. Worn out cam chain guide and/or cam chain can make lots of noise at any or all rpm.
The cct is self adjusting, however, as you say, temporarily rotate/push on, with a small flat screwdriver in the end of the cct with the engine running. If this eliminates or markedly changes the noise, you may have found the problem.
Also, make sure the engine oil isn't diluted with fuel. If in doubt, change the oil and filter.
Yes, there was gas in oil. I hadn't ridden it far.I suspect you also have fuel in the oil. do not run like this. Might be the source of the knocking. Not an expert on carbs here, maybe others can direct you on exactly what to check re: pistons full of fuel.
There was fuel in the oil. Lucky not much and didn't run it long at all. Changed oil and it helped quiet it.I suspect you also have fuel in the oil. do not run like this. Might be the source of the knocking. Not an expert on carbs here, maybe others can direct you on exactly what to check re: pistons full of fuel.
That's good info. No, it wasn't well maintained I'm finding out. I bought it with my heart, not my head. It was a theft recovery, I got it for 1Ahhh, yes, Carbies....... I remember them......... first thought I had about them is they may have blocked jets and malfunctioning needle's and seats - typically this causes the float bowls to overflow onto the crankcases and the floor.
Blocked jets will make starting and idling difficult and it will run rough anyway. Hopefully the vacuum diaphragms on the CV slides are in good condition and everything just needs a good wash and blow clean. Dismantle and layer the parts out in order as you work down to a bare body so it is easy to reassemble after all bits have been cleaned.
Others will also recommend removing the sump to inspect the oil pick up screen if the bike hasn't been used regularly or not had an oil change for several years and the oil has gone coal black and sludgy. If the oil still has a hint of brown color in the sight glass (does a carby BB have a sight glass?...... my FI only has a dipstick).... then it may have been changed just a few thou ago.
It is a good idea to drop the oil regardless, and smell test for fuel contamination...... as fizzy and the boys warn, oil will be diluted by fuel and running the engine will cause extensive damage to bearings etc.
At this age the bike will be a restorers project if it hasn't been maintained well, but hopefully all you need do is clean a few bits and check/adjust a few others and replace the usual culprits like plugs, filters, coolant, brakes etc etc. Be careful if you go as far as greasing the swing arm - there is a set procedure for tensioning the swingarm axle so a good read of the workshop manual in the reference section of the forum is a must.
I'm not sure why fuel has leaked into the cylinder head, unless it's just from flooding while cranking the motor..... you'll have to go over all the ageing, neglected bits, and replace any cracked hoses etc as you find them. There will be info in the workshop manual trouble shooting section, and the forum members will help whenever you ask........
Lets hope it's just few gaskets and hoses and a clean up and tune.........
Thank you so much. Im not sure if I have said anything but I think found problem to my power loss. The number one cylinder coil plug keeps popping up. Don't know why but I made a device that holds it down and so far no more stumbling. However, the carbs still need to be gone thru....no doubt about thatCheck again for fuel in the oil....... my FI model has a fuel pressure regulator that can go bad over time but I'm unsure what the carby 98 has........ something from memory of way past carby bikes tells me a leaking fuel vacuum tap is bad news and a new gasket and thorough clean is needed.
Go to the reference section on here and dig out the early models workshop manual - I have downloaded the FI models manual........ it will help problem solve and may even have pics you need.
This link should work......
The plug cap popping off the spark plug? ......... ........ there must be a reason why this is happening to one cylinder and not the others.
Have a good look with a torch, down the plug shaft, for something that shouldn't be there, or check the spark plug is not cross threaded and on an angle, and that the screw on tip has been removed to expose the bare thread the plug cap needs to ratchet onto...... maybe something has broken off the plug cap and is preventing it from staying locked onto the spark plug? Put a flat screw driver into the plug cap end and tighten if loose. Something isn't right if it pops off......