T160 tacho drive oil leak

Flatspot

Flatspot

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Today while out for a ride I discovered an oil leak, shock horror, it’s a Brit bike obviously. But the only leak is this one. It’s coming out of the tacho drive cable 2 inches above the end where it attaches to the drive unit. Looking at the parts book I’m not sure which oil seal is faulty as the leak is not where it attaches to the motor.
T160 tacho drive oil leak
T160 tacho drive oil leak
 
I don’t allow it to wet sump. As soon as I’m not riding it I will vacuum pump the oil tank empty. Then it will be laid up until next time.
 
Some things I’ve looked at today

I’ve removed, stripped, cleaned and refitted a fully greased up tacho drive unit. Everything appears to be normal as it’s very low mileage.

Then drained the primary and retrieved the correct amount of oil, refilled it with 380ml of 20/50, adjusted the chain while I was there.

I’ve removed and blown down the breather hose and there were no obstructions.

However, and here’s possibly the root of the problem, it does burn oil, it’s very smoky riding at all revs. It runs very well despite this. It is a very low mileage bike, but had been laid up for countless years before I rescued it from being a display and recommissioned it. Yesterday I did 100 miles on it, maybe the 3rd time I’ve ridden it since I got it 2 1/2 years ago, and I’d only done maybe 30 miles before on it after my heart surgery.

(Strip down? :eek: )
 
Strip down? Maybe, but first I’d just try properly thrashing the arse off it… perhaps with some break in oil in it ?

It’s burning oil AND your oil is black as coal. Both are symptoms of rings not doing their job.
 
Ah, you mean an Italian tuneup ;) I will definitely give it a go. Can you give a recommendation for the oil? (I’m not meaning to get into an oil thread, but this is rather specific to giving it a thrash) I’ve got a feeling I may have seen some ‘running in’ oil in the shop where I worked. When I first ran my turbo Busa I had to use straight 30 mineral for a hundred miles or so, before going to 5/50fully synth
 
Flatspot said:
Ah, you mean an Italian tuneup ;) I will definitely give it a go. Can you give a recommendation for the oil? (I’m not meaning to get into an oil thread, but this is rather specific to giving it a thrash) I’ve got a feeling I may have seen some ‘running in’ oil in the shop where I worked. When I first ran my turbo Busa I had to use straight 30 mineral for a hundred miles or so, before going to 5/50fully synth
Click to expand...
Can’t give any specific recommendation I’m afraid, but I’m sure others can…
 
I had this exact problem on my O.I.F. 930 T160. It was the small counterbore in the cylinder base area where the rockerbox drains into. It was partially blocked by the cylinder liner. If I remember correctly it was caused by the larger diameter liner, but it maybe the gasket is blocking it on yours.
 
So to today - it is blisteringly hot here right now for these temperate climes - I have refilled the oil tank with Morris Running in oil 30 - ooh it is so runny like the wife’s cooking oil not thick and gloopy like a good 20/50

Then I removed the black cap silencers as the left one is running with smoky oil and the centre cap rattles. Technically I think it’s f**ked.

Luckily I have a spare pair of peashooters off my Commando and have fitted them. They really sound good just on the drive. Then a neighbour from down the road wandered past on his morning walk and said how he liked both my bikes, and we passed comments about the past (he’s a good 85 I reckon) and various bikes. I mentioned I’m also doing a Triton and he told me how he used to live in Twickenham and Dave Degens was local to him racing up and down the road on his. Small world innit?

I will try and get out later when it cools down a touch.
T160 tacho drive oil leak
T160 tacho drive oil leak
 
Flatspot said:
So to today - it is blisteringly hot here right now for these temperate climes - I have refilled the oil tank with Morris Running in oil 30 - ooh it is so runny like the wife’s cooking oil not thick and gloopy like a good 20/50

Then I removed the black cap silencers as the left one is running with smoky oil and the centre cap rattles. Technically I think it’s f**ked.

Luckily I have a spare pair of peashooters off my Commando and have fitted them. They really sound good just on the drive. Then a neighbour from down the road wandered past on his morning walk and said how he liked both my bikes, and we passed comments about the past (he’s a good 85 I reckon) and various bikes. I mentioned I’m also doing a Triton and he told me how he used to live in Twickenham and Dave Degens was local to him racing up and down the road on his. Small world innit?

I will try and get out later when it cools down a touch. View attachment 115553View attachment 115554
Click to expand...
A t160 on pea shooters brings joy to your ears
 
Well that hasn’t helped at all in a way. I’ve been for a very spirited 30+ mile ride and noticed this once more - it clearly is nothing to do with the tacho drive. It’s too short a run to deglaze the bores or stuck rings and needs more running I reckon.

The pushrod tubes are dry.
The rocker cover gaskets are dry
The cylinder head gasket area is dry
All exactly as it has been apart from all the black oil around the lh exhaust stub area. I thought I cleaned that all away with brake cleaner when I did the tacho drive regrease. I’m positive I did, I think.

Note though that the oil is black as midnight. Yet when I dipped the new fresh oil in the tank it is still clean.
T160 tacho drive oil leak
 
I pulled left and right plugs, both are rather black and a touch oily but I’ve seen worse.
 
Not what I wanted to hear, but it’s not surprising I suppose. That’s going to be a job that’ll have to wait for quite a long time, certainly no earlier than next year as I’ve got too much else going on right now. I may even consider selling up.
 
Fast Eddie said:
And / or post #9 ?
Click to expand...
Thanks, I saw that too and it also requires a stripdown. Something I have no desire or time to consider. Life and old age is doing it’s damnedest to stop me from enjoying myself, this is just another concern that’s stacking up and making me want to just pack it all in. Since my heart attack and surgery I have less tolerance of what maybe minor details to other people. Even my lovely new Mercedes motorhome has a couple of issues - one of them the local Merc dealer is currently unable to provide a solution to. Believe it or not I need a new windscreen, under warranty, and they don’t have anyone to actually fit the fricking thing. :mad: You pay £150k and expect far better service.
 
Flatspot said:
Thanks, I saw that too and it also requires a stripdown. Something I have no desire or time to consider. Life and old age is doing it’s damnedest to stop me from enjoying myself, this is just another concern that’s stacking up and making me want to just pack it all in. Since my heart attack and surgery I have less tolerance of what maybe minor details to other people. Even my lovely new Mercedes motorhome has a couple of issues - one of them the local Merc dealer is currently unable to provide a solution to. Believe it or not I need a new windscreen, under warranty, and they don’t have anyone to actually fit the fricking thing. :mad: You pay £150k and expect far better service.
Click to expand...
I hear yer. Things can get like this sometimes.

Now is not a good time to be selling off Brit bikes tho. Put it to the back of the shed with a note about the issue and your thoughts and come back to it another day.

Or… give Neil Beadling a call and have him fit one of his 850 kits and refresh the top end for you… it will transform the bike…

Save your energy for kicking someone’s head in at the motor home shop !!
 
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Regarding the tacho oil leak, apparently this was common on early T160's, and has just happened yesterday on my friends early T160 that also has this problem, so is yours (Flatspot) an early T160?

The factory moved the tacho drive from the centre front of the crankcase on the T150 where this issue wasn't a problem, to the end of the camshaft on the left side of the l/h crankcase on the T160, and the oil leak is to do with (as I understand it) the drive scrolls on the camshaft directing the oil towards the tacho drive where it then appears out of the bike, and not crankcase pressure.

The factory put a hole in the later crankcases somewhere in this area to allow the oil to drain back into the crankcases and so have an escape route rather than be directed to the tacho drive.

If the engine isn't going to be stripped down any time soon to drill this hole, to improve matters, fill the tacho drive with grease and again when the leak starts to re-appear.
 
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