Valve clearances on a part 650SS

Very many thanks gents. I will report back when I eventually take the motor down, hopefully during this Summer.

Thanks for the e-mail, Phil.

Hi again folks, I dug this one back out early because there is much in common with the 57 on rocker spindle thread.

I'm just about ready to get started. First job will be to drain the sump and replace the oil. Then tank off and rocker covers off. I use a small tank tied to the handlebars. Start the engine and check for oil going to the rockers and of course obvious noise.

Might have to keep going till we get to the bottom of it quite literally. I'm using this opportunity to replace the gearbox too, with a rebuilt one that has got the superblend layshaftbearing.

I'll keep you posted as promised. Thanks for all the tips above, all digested and being considered.

Well I don't intend to give up on this machine, even if the prognosis is not good!

I drained all the oil from the sump, despite the low miles it had turned black overthe two years standing. I wonder if I can put anything down to the Active8 I was advised to try, to cure the noise? The engine filter (Bottom of cases) showed no real debris.

Just out of curiosity I rubbed my finger around the inside of the oil tank, now I know that it had been wet sumpedfor over a year but I was not expecting to find small particles of rust like grit!

The tank had to come off of course and degreased. After a good wipe out I was far from happy and so the tank is currently sealed up, filled with soda crystals mixed with water, a lump of iron with a battery charger connected. See what that does 24 hrs later? The tank was fine when I put it on and I can only imagine two things:

1) the cases were bead blasted and not cleaned out? (I bought the engine rebuilt)

2) Something in the engine broke up and sent debris into the return (Unfortunately some should have gone to the rockers or maybe it blocked the rocker feed and hence the noise?

As promised, I'll keep you posted.

Thanks Phil, I have now taken the plugs out and alarmed at the R/H plug hole, which was full of oil. wasn't like that 50 miles before!

I agree with you, no more Active8, a lesson well learned.

Time to unplug that oil tank..........

Anna, it's not that, 100%. You should know that I only use BP Ultimate, even in my more modern car. Why anyone would want to put a solvent in their tank, known to attack the fuel system is beyond me. And a lower MPG if the damage wasn't enough.

Anyway, my oil tank is back on with rust and debris removed and the filter washed out in BP Ultimate. (What a waste) Just a word of warning if you are going to clean a tank out with the soda crystals / water and electricity method. You need a fairly old and strong battery charger. The newer ones don't seem to work for this and the small motorcycle trickle chargers overload and melt.

I have half filled the tank with Golden Film and with the plugs out spent about 10 minutes kicking it over before I ran out of puff. Another 5 or 10 minutes should have the oil back round to the tank.

Of course I forgot the filter in the oil pressure dome, should have thought of that before I put the oil in, another job to do.

After all that it will be off with the rocker covers and start up, listening for the gremlins. I'll let you know what is found. Be a miracle if all is quiet now!

Oil circulating, rocker caps off, plugs back in and start up time.

Oil getting to the rockers after finger on the return pipe. Oil in the R/H spark plug hole was down to a leak in the right exhaust rocker spindle cover, will need to fix.

The rattles got worse as the engine warmed up but found that some of it was the exhaust locking tabs rattling about. Probably be a bit quieter still with the rocker covers back on. Will check the tappets first. The 2-1 exhaust will create a bit more noise too.

The bike suffered the classic big end on the way out symptoms previously when under load but I reckon that with some gentle riding with fresh oil, it should add to the 132 miles completed so far without anymore than a bigger rumble before the motor needs to come apart.

I'll keep you posted...

Thanks David, I did the rod knock test by finding TDC and then just starting the down stroke put a screwdriver in the plug hole. Press down and listen and feel for downward movement in the piston. If it falls there is play in the shells. I couldn't detect anything. That doesn't mean there isn't a problem in this area, just that I couldn't detect one. The noise, a bit like yours though is there and I wish it would go away.Maybe not so loud....

I'm interested to know what you found with your engine on stripdown and how far you rode it or could have ridden it before grinding to a halt.

I plan a 120 mile gentle ride in the next week.

I don't think it is pushrods, David. The head was off when I bought the engine. The head is not 650ss, which always complicates things but my money now is on cam followers. That being the case, the engine can rattle for thousands of miles. (I think)

On Tuesday I did my annual ride to Whitby, well just South of there actually. Return mileage was 108 and MPG was a disappointing 49.

A few checks before I set off, the plugs were slightly sooty but revealeda nice golden brown colourwitha touch of tissue. I put this down to idlingto empty the single carb at the end of a run, rather than my granddad's old trick of turning off the fuel 1/4 mile from home.

I pumped up the tyres and checked the oil levels. I over filled the oil tank (Morris 20-50) and by Pickering for my first BP Ultimate fuel stop found oil all over my back tyre. Silly bugger! I checked the primary oil and 1/3rd pint came out with the bike on the centre stand! I checked it after the 108 mile run the next day and got about 20 drips out so the problem is negligible. The 1/3rd pint will have accumulated while the bike was stood for two years. (Wet sumped )However, this has led to the clutch plates being contaminated with mostly SAE40, used before the 20-50. Kicking the bike over has become progressively more difficult with slip on the kick starter and yet surprisingly no slip with the drive and smooth gear changes. Incidentally, I checked the EP90level in the gearbox and that was at the correct level, so it is mostly engine oil from the crank seal and not gear oil. I'm going to take the primary case off to release the oil and run it dry until I lay up the bike in 5 or 6 weeks.

On the run it took 10 minutes or more to set off (Due to the kick start slipping) and riding along at 40 mph was awful, don't get me wrong, this motor is smooth all the way through but the rattle is like a labouring engine. I don't think the 20Tgearbox sprocket helps. Onto the A64 duel carriageway, going along between 55 & 65 mph without load on the engine, in other words getting up to speed and then backing off slightly just to maintain speed and it was a different bike, the rattle all but gone. After my first fuel stop before heading out over the NY Moors I put on my neck warmer and pulled the top over my ears. These things are really great, once I got over 50 mph you wouldn't know there was an issue! There are about 5 very steep gradients on this run the bike took in its stride but might have had an effect on fuel economy, plus I tried to keep the bike out of the lower revs rattle zone.

No more starting issues through a slipping kick start until the next day. Soon after arriving home I had to wash down the rear of the bike but I think the oil is about normal max now and I don't believe the engine is using any oil (Save a slight leak at the crank) and the oil appears to have stayed clean.

250 miles on the clock now and the rattle is no worse but I'll keep you posted. Should be much better with these clutch plates clean too.

Thanks Robert, actually the main bearings were replaced before I bought the enjine and I was given the old ones as there was nothing wrong with them. I'll keep this in mind but once I have sorted the clutch I feel this will be a good runner for some time to come.

The clutch is sorted, with no drive at all now and no time to strip it I decided to try a quick fix. With all the oil cleaned up I pulled in the clutch lever and sprayed in Millers Brake and Clutch cleaner between the slots. I also tightened up the clutch springs by half a turn each. Finally I sprayed the primary chain with WD 40 chain wax. I just hope the clutch cleaner did not find its way to the rollers?

At last I had good drive, the engine started second kick. This arrangement will do for the next 5 or 6 weeks, until I lay it up till Spring, when I can put some SAE 20 in the case.

Once you get past 50 mph this is a fantastic bike to ride. I'd be on my restored 99 but after a month, I'm still waiting for the DVLA. Before the local DVLAoffice was closed, all of this was a simple appointment with the bike in the back of a van and job done.

Any issues with the 650 and I'll let you know, till then, let the rattle continue, it's not getting any worse after all!

OK Robert, you win. Now I have put the primary cover and footrests back, Ill put some SAE 20 in tomorrow. Actually I use ATF in my Commando primary but I prefer 20 in the earlier machines. ( Even 30) Regarding the 1/3rdpint of engine oil (mostly 40) in the primary case, I'm thinking that after standing for two years with a wet sump that this might be par for the course, rather than a crank shaft oil seal failure? Any ideas?

I forgot to mention that there was a fair bit of emulsificationin the oil tank after my 108 mile run, but I put most of that down to the breather that feeds into the top of the oil tank, no big deal I don't think. Some put this down to valve guides though!....

The knock and rattle goes on.

First point to Anna is that although this thread is about valve clearances and rattles there are other issues along the way and best kept under one roof, same bike different issue and the rattle continues.

The clutch played up again, slipping when turning over with the 20 SAE oil in the cases. Turned out that the push rod needed adjusting half a turn. Next time the outer case comes off I'll slacken those springs half a turn each to make the clutch lighter and to give the cable an easier time.

The tappets were adjusted from 8 & 6 thou to 6 & 4, (Remember, not a 650SS head) this made a slight improvement but there is still a distinctive clanking going on. I doubt the issue will be end float, though easy to check with the timing cover off. With the head and barrels off the big ends and cam followers can be considered as culprits.

Apart from the noise at lower revs, the heavy clutch and weep from the kick startshaft I may as well enjoy the bike and bit by bit get to the bottom of it. (Hopefully not the bottom of the engine)

My main focus now is the pre F/bed Model 50. Watch that space!

I will close this thread when I can tell you what was causing the clunking in the engine. Unless the kind Webmaster beats me to it?

PS: Back on the road with 132 miles on the Smiths Chrono a couple of months back, now 312 miles and clunking away and a real smooth joy at over 50 mph.

So, Manxmen knock as well! Loose cam followers is my favourite now but interesting comments, Phil.If that's all it is then they won't do any harm.

Do let me know what you find, Anna, during your winter rebuild. Mine will have to wait until after the long overdue pre f/bed Model 50.

Hope your water works get better soon, Anna.

Meanwhile, you hum it and I'll play it. Knock on!

I posted this sound file on another very related thread so you have something to compare with.

Now 374 miles on the clock and the noise no worse, a slight improvement when the tappet clearences were reduced from 8 & 6 to 6 & 4. Remember this is an earlier or non 650 head. (Single 30mm Amal)

Fuel consumption is currently poor with 49 mpg on a run and 43 mpg with local running. Not very good when I can get 68 on my 850 Commando!

I run a 20T gearbox sprocket and the noise is worse in top gear @ 40 mph. 50 on it is much better until you can't hear it, yes the wind will soak up most of the racket but the bike goes really well, especially at higher speeds. Perhaps partly why the MPG is poor, even with a single Amal?

Once I finally get my 99 registered for the road I'll send a sound file on that. It also runs on Morris 20/50 and the sweetest Norton twin you ever did hear. However, I'll try going back to the SAE 40 in the 650 as suggested but Charles isn't going to like it! (I have plenty as I use straight 40 in my singles)

I don't think I ever posted a picture. Exahaust is 2-1 I happened to have handy. While it's going well, despite the noise and poor fuel consumption I need to work on I may as well keep it going while busy with a pre F/bed!