Where does the noise come from?

lcrken

lcrken

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Just curious about the source of the threshing machine noise from the engine. I was warned to expect it before I bought the bike, so I'm not complaining. But I do wonder if anyone knows what causes it. It sounds to me like it's coming from the primary, so I'm guessing it's just a result of the gear drive system. From the pictures, it doesn't look like they used a split gear to take up backlash, although I can't tell for sure. Straight cut gears are notorious for this sort of noise. Anyone got any more info on this subject?

Ken
 
lcrken said:
Just curious about the source of the threshing machine noise from the engine. I was warned to expect it before I bought the bike, so I'm not complaining. But I do wonder if anyone knows what causes it. It sounds to me like it's coming from the primary, so I'm guessing it's just a result of the gear drive system. From the pictures, it doesn't look like they used a split gear to take up backlash, although I can't tell for sure. Straight cut gears are notorious for this sort of noise. Anyone got any more info on this subject?

Ken
Click to expand...
As BritTwit said. Balance shaft gear is main culprit. It can be fixed tho. We have a tension setting tool to make it easier and perfect. But be careful its very easy to over tension which is mostly the case in pre 2015 models. The assembly team have gotten better thats for sure. Also straight cut gears and timing chain could be a little loose.
 
Thanks for the replies. I don't think it's the timing chain. I've heard that before on old Commandos, and this doesn't sound the same. But I could be wrong. Besides, it really does seem to be coming from the primary side. I'll try to do a little sound probing to see if I can localize it a little better.

The bike came with the SB pipes, so I really only hear the noise at low speed and idle. It really doesn't bother me much. I fired it up next to one of my friends yesterday, who is serious Harley guy, and he was really freaked out by it. He was positive it was about to explode. Almost worth it just for that.:)

Richard, is that tool available from CNW?

Ken
 
lcrken said:
Thanks for the replies. I don't think it's the timing chain. I've heard that before on old Commandos, and this doesn't sound the same. But I could be wrong. Besides, it really does seem to be coming from the primary side. I'll try to do a little sound probing to see if I can localize it a little better.

The bike came with the SB pipes, so I really only hear the noise at low speed and idle. It really doesn't bother me much. I fired it up next to one of my friends yesterday, who is serious Harley guy, and he was really freaked out by it. He was positive it was about to explode. Almost worth it just for that.:)

Richard, is that tool available from CNW?

Ken
Click to expand...

Tool is available from CNW. You’re going to need to get a new spring from NORTON. Be extremely careful not to over stretch the new spring at install. Practice with the old one a few times first. You’re also going to want the GEAR JAM tool. All info is in my manuals.

There is one more item to note. This really was an issue on 2013 and some 2014 bikes and we stressed to factory and they fixed for sure by 2015 but the ring gears come loose and shear off the bolts. This is the gear attached to the clutch basket. In Canada we started to PIN (drill and dowel) the ring gear to the basket. My dads 2013 SE had his ring grear break off at a traffic light. I was next to him. He thought his bike was getting louder and sure enough. Thankfully a block from home. I made a post about it. I’ll try to find it and bump it.
 
I'll check the ring gear, and add the dowels. I need to order some other stuff from CNW, so I'll pick up the tools at the same time.

Ken
 
richard-7 said:
Tool is available from CNW. You’re going to need to get a new spring from NORTON. Be extremely careful not to over stretch the new spring at install. Practice with the old one a few times first. You’re also going to want the GEAR JAM tool. All info is in my manuals.

There is one more item to note. This really was an issue on 2013 and some 2014 bikes and we stressed to factory and they fixed for sure by 2015 but the ring gears come loose and shear off the bolts. This is the gear attached to the clutch basket. In Canada we started to PIN (drill and dowel) the ring gear to the basket. My dads 2013 SE had his ring grear break off at a traffic light. I was next to him. He thought his bike was getting louder and sure enough. Thankfully a block from home. I made a post about it. I’ll try to find it and bump it.
Click to expand...

g'day Richard, a customer of mine has a 2016 961CR with the balancer / clutch issue & only done 1,200 klms!
does anyone in Australia stock your tools?
thanks
 
hywayman said:
g'day Richard, a customer of mine has a 2016 961CR with the balancer / clutch issue & only done 1,200 klms!
does anyone in Australia stock your tools?
thanks
Click to expand...

COLORADO NORTON WORKS ships world wide. Hope this helps some.

Richard
 
Actually, solving the mechanical noise issue is quite easy...

Just get a mate to buy a dry clutch Ducati and accompany you on every ride, the 961 will sound as sweet as a nut !!
 
I have received a replacement clutch basket, hub & balancer gear today.
started putting it all back together after several weeks.....
can anyone advise on the balancer gear & clutch hub nuts, these are the same but i only have 1 thick hardened washer
photos taken on tear down show 1 on the balancer gear
is the clutch hub meant to have the same washer?
thanks in advance
 
hywayman said:
I have received a replacement clutch basket, hub & balancer gear today.
started putting it all back together after several weeks.....
can anyone advise on the balancer gear & clutch hub nuts, these are the same but i only have 1 thick hardened washer
photos taken on tear down show 1 on the balancer gear
is the clutch hub meant to have the same washer?
thanks in advance
Click to expand...

I have a manual on this.
 
g'day Richard, i have looked at your manual but i can't make out clearly in the photos if both the split balance gear & the clutch hub, both should have the thick hardened washer. i'm now assuming this bike has been assembled without the clutch nut washer!
 
Clutch Hub does NOT have the washer. If we ask Rob Jameson to be sure would be best.
 
Mine backed off until the whole basket was loose. Worth having a look see before damage is done.
 
richard-7 said:
Tool is available from CNW. You’re going to need to get a new spring from NORTON. Be extremely careful not to over stretch the new spring at install. Practice with the old one a few times first. You’re also going to want the GEAR JAM tool. All info is in my manuals.

There is one more item to note. This really was an issue on 2013 and some 2014 bikes and we stressed to factory and they fixed for sure by 2015 but the ring gears come loose and shear off the bolts. This is the gear attached to the clutch basket. In Canada we started to PIN (drill and dowel) the ring gear to the basket. My dads 2013 SE had his ring grear break off at a traffic light. I was next to him. He thought his bike was getting louder and sure enough. Thankfully a block from home. I made a post about it. I’ll try to find it and bump it.
Click to expand...

here?

https://www.accessnorton.com/NortonCommando/starter-ring-gear-issue.18877/
 
Ok, being a newbie it seems I am reopening old threads. So I have some comments on the rattling noises emanating from the engine:
1. It is true that the all gear primary drive is by nature more noisy than a chain or belt drive
2. It also true that the main cause of the "extra" noise is the counterbalance gear.
3. I am fully convinced that a simple redesign of the gear can eliminate most noises.
4. The redesign is reversing the taper so the gear mounts "inside out" and reversing the counterbalancer direction.
5. There is a very logical reason for this and it goes like this:
As assembled, both parts of the counterbalance gear engage the crankshaft AND the primary (clutch shaft) gears. By both parts I mean the "main" part of the gear and the "narrow", spring loaded antibacklash component. THAT IS A NO-NO! By definition, an antibacklash gear pushes back (thru the spring) against THE non driving side of the driving tooth of the crankshaft gear. But what is happening in our primary cases is not that, each antibacklash gear egages one tooth with the crankshaft AND ANOTHER TOOTH ENGAGES THE CLUTH GEAR! The end result is that the antibacklash gear will adjust to the TIGHTER tolerance side (engaged tooth), so at times the full intermediate gear will mesh with the crankshaft at zero backlash and sometimes with the clutch, causing unneeded rattling noises and vibration. An antibacklash gear MUST engage ONLY ONE gear, not two!!!
If we look closely in the cases we can see that, if the countershaft gear is reversed, the narrow side only engages the crankshaft gear and that would allow the antibacklash mechanism to actually work. I suspect that this alignment shows that the original design was accounting for this, but someone screwed up and reversed the taper in the gear and either nobody noticed it or they thought nothing of it!
I don't know if there is enough meat and space in the existing gear ( and the primary case) to machine out the center and install a reverse taper insert in it and reverse the counterbalancer direction, I did not measure things when I had the case open, but I am sure that if someone tried the result would be well worth it, but of course a brand new gear with the correct taper direction would be almost magical.
Any ideas / connections with cintered metal manufacturing?
 
Well, if true then it seems a solution can be had.
Bad news - the technical requirements to perform the fix are way above my pay grade.
Maybe it's something that Matt at CNW, or John Snead can take a look at and produce a new 961 product fix.
Would be nice to quell the excess noise from the primary.
 
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