Norton 961 Commando a keeper?

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To be honest I was looking at a .25 bar cracking inline not a complete tap so to speak. Your post though answers a question that I had pondered, in that where in the scheme of things is the check valve as I had noticed that the "feed" was or seemed to be elsewhere.

Started it today with a clear tube, no oil puked at startup, however, went for a 10 min ride up the road and after stopping I actually heard a gurgle from the R6 plastic separator and hay presto opened my air-box drain tap and filled the bottle.

Soooooo..... maybe its the pump after all, but why after a 10 min ride, couple of 2nd 3rd,4th 6.5/7k rpm blaps does it do this, too much oil in the crank would suggest weak scavenge no ?
Interesting that you could hear a gurgle from the separator, but are you sure that was when the oil reached the airbox?

I would again suggest that you drain the oil bottle, take the airbox plug out, and just start the bike and run it for 15-30 seconds while keeping an eye on your overflow bottle. See if you're getting out of the airbox at startup. That would suggest one of two issues - oil accumulating in the sump after shutdown, or excessive blowby from the piston rings. Since my problem was accumulation of oil in the sump, I know this can be an issue, it would be my main suspect.

If the oil is only entering the airbox while riding the bike, then I think you may be correct, the scavenge circuit of the pump may not be working properly. The crank is forcing the excessive oil from the sump into the breather and up into the airbox.
 

Bluey72e

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Interesting that you could hear a gurgle from the separator, but are you sure that was when the oil reached the airbox?

I would again suggest that you drain the oil bottle, take the airbox plug out, and just start the bike and run it for 15-30 seconds while keeping an eye on your overflow bottle. See if you're getting out of the airbox at startup. That would suggest one of two issues - oil accumulating in the sump after shutdown, or excessive blowby from the piston rings. Since my problem was accumulation of oil in the sump, I know this can be an issue, it would be my main suspect.

If the oil is only entering the airbox while riding the bike, then I think you may be correct, the scavenge circuit of the pump may not be working properly. The crank is forcing the excessive oil from the sump into the breather and up into the airbox.
Yeah did this, and to think on it I have tested a few times now with a clear plastic crank breather and on NO occasion did I ever see a glut of oil pumped out at start up, I see small oil movement within the clear vent pipe as air moves back and forth.

I have a crank breather (non return) that would stop the back and forth movement of gasses and only allow blow by gasses out, cant see that this would stop excess crank oil coming out though. ??
 
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Being one of the latest 961's mine seems to have all the updates and runs like a dream luckily. Just returned from a near 100 mile blast over the North Yorkshire Moors and can't get the smile off my face. Even through a 10 minute wintry downpour, it never missed a beat. Can't fault it, gearing, throttle response, handling, tickover hot and cold, comfort, a gem. Even tickles your bits as you proceed briskly through the gears.
 
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Being one of the latest 961's mine seems to have all the updates and runs like a dream luckily. Just returned from a near 100 mile blast over the North Yorkshire Moors and can't get the smile off my face. Even through a 10 minute wintry downpour, it never missed a beat. Can't fault it, gearing, throttle response, handling, tickover hot and cold, comfort, a gem. Even tickles your bits as you proceed briskly through the gears.
It doesn't get much better than that.
Cheers.
 
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Being one of the latest 961's mine seems to have all the updates and runs like a dream luckily. Just returned from a near 100 mile blast over the North Yorkshire Moors and can't get the smile off my face. Even through a 10 minute wintry downpour, it never missed a beat. Can't fault it, gearing, throttle response, handling, tickover hot and cold, comfort, a gem. Even tickles your bits as you proceed briskly through the gears.
Sounds like a match made in heaven .
 
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She started fine at the weekend, same petrol. All I did was park her up and put on trickle charge. Battery is back on charge, I will try again later but I have a feeling it will be tank and seat cowl off then hours of unplugging and checking, hours scrolling through this forum to locate common/frequent issues, lots of hair pulling, ordering unnecessary spare relays and other sensors 'just in case', only to find that my ecu has given up the ghost. I'm even more miffed 'cos today I put road tax on her for 6mth!
Oooh! - the cost of a new ECU doesn't bear thinking about.
 
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Oooh! - the cost of a new ECU doesn't bear thinking about.
Some people can't handle change but for those that can, just 19 miles to go before my 961 is run in , out this morning over the Moors and running like a dream. 781 miles, no probs. 3 to 4mm of oil carry over to the little bottle. Back brake's a bit useless but who needs them . Here's to the summer .
 
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Sounds like a match made in heaven .
The newer 961 's were getting better . If there was good quality control and consistent supply all 961's could have been good bikes. Keep an eye on the bottle level especially when the sustained speeds pick up (more than 70MPH sustained) . There is room for a 4 oz bottle there with no mods , if you need or want more reserve capacity .

I had another look and the Euro 4 has a purge control valve using the space I used for a larger bottle . The 4 oz bottle may still work you have to try it and see.
 
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