Topic: 100 miles

[hymodyne]

After three days, I've covered 100 miles on this bike, taking trips of 10-20 miles at a time.  Near the end of my last trip, I noticed a tappet or  upper engine sound, one that speeds up when  the RPMs increase, but gets less noticible then too. I'm assuming that its oil-related. the dipstick reads full, but at very low speeds or at idle the red light for oil comes on after the bike is warmed up.  I've been using an inexpensive 10W40, but need suggestions for the best oil for this age of machine ('72 CB500/4)


hym

[scondon]

For the upper engine noise, check for a loose valve tappet or exhaust leak where the header connects to the head.

[eldar]

If your oil light is coming on, you may want to check your oil pressure. The pump may be wearing out. You can also drop the pan and pull the pump and check the tollerances and see if they are in proper operating range.

[MRieck]

I'd say the pressure sensor and the pump are at the end of their respective lives.

[Paul]

The Oil pump on the 500 ....and the 550 is behind the front sprocket cover (These unlike the 750's have a wet sump.)
So...for all you 750 owners who get to work on a 500....don't drop the pan without draining the oil, you'll get wet.
It seems that if the oil light is comming on at low revs and when the oil is hot...the pump is not pushing it hard enough and may be worn. Then again, I had the same symptoms, changed the o-ring to stop the pump cover leak and it turned out to be a faulty pressure switch (Located on top of the oil pump itself.)

[jbailey]

Since this and most bikes don't use hydraulic lifters it is probably not oil related noise.  A car with a sticky lifter will make ticking noises at idle.  Our bikes have a noisy valvetrain by design, but excessive ticking may be due to inproper gap.  I would double check your valve gaps CArEFULLY, it is a very finicky and tricky procedure.  If your bike has been sitting for a while you could have a valve that is sticking.  On a car you could run a little Marvel Mystery Oil (Kooky name, great stuff) to loosen up a sticky lifter or sticking valveguide.  I don't really know whats in it, so wouldn't try it since it could cause clutch slippage.  If your valve gap is right on, then ride it and see if it quiets down.

I use Shell Rotella T synthetic 5w-40.  It's about $13 a gallon at WalMart.  Great oil for the price.  It contains NO moly so it's clutch friendly.  Check around the internet and you will find Rotella is a great motorcycle oil, you just don't have to pay for the little motorcycle picture on the bottle.

[SohcCBs]

A slight bit of tappet noise is not unexpected, but you should check the gaps to make sure.  My 750 does it regularly, especially after crankin' it up some.  I used to check it tappets all the time, cause it drove me nuts, but I've learned, mine jsut does that and still stays within reasonable tolerances.

[pmpski_1]

I just had the oil pressure light problem on my 74 550. I installed a new pressure switch and o-ring and it seems to have solved the problem. Unfortunately I wasn't too scientific about it so I don't know which one did the trick. I'm pretty sure that I have the wrong size o-ring though. It's a 45mm and from the information that I've gotten here the correct size is 44.6. I haven't been able to find the cross section size.

The pressure switch was ~30 bucks with tax.