So there I am floating along on the highway at about 60-65mph for about 100 miles on my way to Vintage at Mid Ohio and all of a sudden a quick loss of power and then my rear locked up! By the time I got it to the shoulder it was idling away like nothing happened. I shut er down and let it cool off for 1/2 hour while chatting with some guy who 'used to have a cb77 just like mine', and then continued on my way for another 10 slower country road miles, motor running fine and sounding pretty much the same as before, maybe a bit more top end mechanical noise, but I ride with ear plugs so everything is louder without em.
Changed my oil at the track and noticed a very light metallic sheen to the oil (maybe it was my imagination?). Checked my plugs and they looked good. Got it home and now it sits and I am wondering what could have happened. right before my trip, the engine was running very well, freshly tuned with new points and condensers, timing right on, cam and tappets adjusted, carbs synched, plugs gapped, oil checked. I had the engine apart 15 years ago+ and 2000 miles ago and honed the cylinders and installed new rings (just because I think). This is the first time I had taken it on a long high speed trip since that time.
So, I'm thinking is it possible that I didn't get the ring end gap right and the rings expanded too much due to the harder use? Not sure what else, maybe low oil pump volume and the piston skirts didn't get enough of the good stuff? One or both carb floats at the wrong hight starving a cylinder (I don't remember adjusting those in a long while)?
Any ideas before I tear into it?
Oh oh, engine briefly seized on a road trip!
thanks for the replies. I'll open er up and check it out sometime soon and will pass along what I find. This is all good because it now give me the excuse to put in a new cam chain while I'm at it.
When the bike seized, I was running 40 weight non detergent oil from Napa (oil thread alert!). When I changed it at the track I put in Amsoil 10-40 synthetic. They just happen to a space set up directly next to my buddies OVBSA display where I was parking the bike, and at $10(!) dollars a quart, I simply couldn't pass up the deal.
Hi,
Well, we will hear from you soon. I won't say anything about the type of oil you use, it's a "hot" item and difficult to talk / discuss about. I once heard from a very importend Honda person that it is very hard to discuss the item from a sceintific point of view, because it's a believe. Jensen assembly of Japanese motorcycles requires great peace of mind (Pirsig)
The oil thing isn't all that difficult.
I just get tired of others with little knowledge (even the ones who worked on them in the late 60's) telling me what oil tp use. I don't care what others use as that's their choice I merely don't need someone inferring/saying that what I do isn't correct. Once again I've been asked what oil I use and the answer is 30W ND and that's all that's there. I don't understand why the bike owner used 40W but that's his choice also. I've seen all to many of these engines seize while being lugged up hill rather than down shift and allow the pistons to run cooler than have them over heat while lugging them on hills. Not sure that's what happened to the fellers engine. ..............lm
would have been nice if you saved the old oil and sent it in for testing.
among things they will tell you are.. viscosity , non detergent oils can and will break down and thicken... so they will test to see if the oil was in spec or breaking down and out of spec. metals... they will tell you how many parts per million of iron, brass, aluminum are in the oil. This will tell you how much wear is happen in the engine and give you an ideal if something bad is starting to happen or already happened... Then they also can test for presence of antifreeze, moisture and other contaminants including fuel getting into the oil. The amount of dirt and contaminants can help also determine oil change intervals for your style of riding or if your oil really works or if you have no frigging clue about what your talking about. In the 60's we found out that certain 30 wt oils did not hold up and either foams like the mobil or locked up like your expierence. One of my buddy had his bike lock up about 5 times, till we finally got him to come over from the dark side.. my advice... look at what all the manufactors run in the bikes today.. similar bikes,, air cooled, high rpm and wet clutches... see what they recommended in the later years just after our bikes were made.. ""jaso rated motorcycle oils have 5 times more anti wear additive than a good detergent car oil."" while a non- detergent 30 wt oil has ZERO additives... thats zero... guys... if you do run 30wt oil, your running the cheapest base oil you can get with the worse results and specs... and if you do, please change your oil every 500 miles and your engine every 5000 miles.. The heavy paraffin chains break down under pressure... the light weight volitals evaporate off, and the ash settles out. So your left with very little friction barrier. This oil was perfect of engine that turn 600 rpms or less. yes, it was and is sewing machine oil and door hinge oil.. and a great creater of sludge.. yes the sluge was the left overs of the oil when heated. Modern group 3 and group 4 oils do not turn to sludge and stay in group and chacter. If filter properly extended oil changes are possible on extreame duty equipment. New tests for oil performance have been designed that did not exist in 1960 and any oil manufactored then would not met any of the wear tests, friction test or performance tests. Sadly I am not making any of this up. Please go read about the japanese motorcycle makes oil rates JASSO, the european ratings and of course the american api ratings. read about each test and what is means. read about how oil is now correctly catorgized into which oils perform and what they can do. I dont sell oil, but I do care about how long my equipment last. so please go read and make up you own opinion. http://en.wikipedia.org/wiki/JASO http://www.thumperfaq.com/oil.htm http://www.sportrider.com/tech/146_0308_oil/index.html http://www.bobistheoilguy.com/forums/ub ... ber=931328 http://rds.yahoo.com/_ylt=A0geu5.82HRKC ... etail.aspx As you see oil is not oil and there is a lot of talk about oil. sadly as new stricter emission requirements have force the automotive makes to remove some additives so that they dont foul up the converters, the newest automotive oil is no onger the best oil for wear.. extreame additives can coat the catalytic converters and reduce their effectivness so they have cut back on some of the better anti wear additives. so a pure motorcyle oil that is specially made just for motorcyles will now do better that the premium motor oils.. but remember that they are a specialty low production manufactor oil, so expect to pay more.. non-detergent 30 wt?? remember that was even before Dr DeBaky did the worlds first heart transplant, before man went to the moon, radios still had tubes and fm radios were only offered on a few cars and turn signals were not required, 4 way flasher were not availible, and record players were standard, and 8track tape playes were just comming online cars had to be tuned up every 10000 miles or sooner, most cars would not start in cold weather, radial tires were not availible, but we got nylon tires that would last 7000 to 10000 miles, oil was change every 3000 miles but you added a quart every 500 to 1000 miles. chrysler was experimenting with a motorola alternator. and ole yeah. gas was 19 cents a gallon, all cars leaked oil and engines lasted 60,000 if you were luckey and didnt throw a rod... any high rpm driving would take out an engine in weeks... and yes honda brought out a revolutionary machine that would turn more than 5000 rpms.... and ran it on oil that was the same oil run in a model t engine.
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