My What Am I Getting Myself Into Combat Build Thread

Saber

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Is there anything on this bike that's not a PITA. Steering bearings o_O. Could not "punch" out the bearing from the inside, so ended up grinding down the inner and outer bearing race so i could get enough bearings out to pop out the inner race so i could get the inner tube out in order to get a bearing puller in, but it was too stuck to pull so i ended up pushing the bearing puller from the other side. My lord!

View attachment 20284
Yes, riding it is (usually) not a PITA.
 

TomU

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Back on the GB. Got the bearings in and camplate.

IMG_2025sm.jpg


Bearings were another pain. Heated up the case and froze the bearings. Trying to get the bearings in straight with a red hot case and freezing bearings was not easy. Also, thought i'd use some locktite bearing compound just to make sure they were in there good and tight. Well the bearing compound ended up freezing to the bearings and they were so tight to begin with the compound totally botched getting them in. So rinse and repeat. Cleaned off the bearing compound and started over. The layshaft bearing went in no problem, but the mainshaft bearing was still tight. Luckily, i had a press but still needed to get the bearing straight otherwise the press pushes it in at an angle and that won't work. Anywho, finally mission accomplished :). Think if i do it again, i'll try it on a cold case with frozen bearings. The hot case seemed to heat up the bearings immediately and that might have expanded them enough to outweigh however much the case expanded with heat. And as for comments on the mainshaft bearing, i got that from CNW and asked Matt about the 2 RS bearing and he said that's what he uses, no problems. So that's what i'm going with

Now just hope i got the camplate timing right :rolleyes:
 

batrider

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Back on the GB. Got the bearings in and camplate.

View attachment 20316

Bearings were another pain. Heated up the case and froze the bearings. Trying to get the bearings in straight with a red hot case and freezing bearings was not easy. Also, thought i'd use some locktite bearing compound just to make sure they were in there good and tight. Well the bearing compound ended up freezing to the bearings and they were so tight to begin with the compound totally botched getting them in. So rinse and repeat. Cleaned off the bearing compound and started over. The layshaft bearing went in no problem, but the mainshaft bearing was still tight. Luckily, i had a press but still needed to get the bearing straight otherwise the press pushes it in at an angle and that won't work. Anywho, finally mission accomplished :). Think if i do it again, i'll try it on a cold case with frozen bearings. The hot case seemed to heat up the bearings immediately and that might have expanded them enough to outweigh however much the case expanded with heat. And as for comments on the mainshaft bearing, i got that from CNW and asked Matt about the 2 RS bearing and he said that's what he uses, no problems. So that's what i'm going with

Now just hope i got the camplate timing right :rolleyes:
Bearings or bushings at room temp and case heated was mentioned and recommended on this forum recently. I usually do it like you did but supposedly the frozen bearing cools off the case quickly and it starts contracting midway through.
 

TomU

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Bearings or bushings at room temp and case heated was mentioned and recommended on this forum recently. I usually do it like you did but supposedly the frozen bearing cools off the case quickly and it starts contracting midway through.
Yeah, that's exactly what happened but not sure if the bearing cooled the case or the case heated the bearings. When i pulled out the bearings to redo, they were quite hot and they weren't in that long (and not fully in either). I think in terms of mass and thermal inertia, the bearings are apt to heat/cool faster than the case because they have less mass. So that would mean the bearings heat more than the case cools.
 
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And as for comments on the mainshaft bearing, i got that from CNW and asked Matt about the 2 RS bearing and he said that's what he uses, no problems. So that's what i'm going with

Now just hope i got the camplate timing right :rolleyes:
I would recomend to remove the inner side seal so it will receive a constant supply of lube and not relie on the grease that it came with. with the outer seal left in plece it will be less apt to flood the clutch release and oil find its way to the clutch but I would still use a clutch push rod seal.
 

Time Warp

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Orginal layshaft bearing. England!

View attachment 20317

From my 1971 FB.

Bearing.JPG

There was nothing wrong with the bearing out of my 850 (both replaced with roller bearings)

Norton Layshaft Bearing.JPG

I have quick machined bearing guide rings on occasion, the ring sits against the surface, the bearing in the ring then has little choice in starting plumb come time to press it home.
You could use wicking Loctite 290 after the bearings are installed, I would second Bill on the inner seal removed (at a minimum)

You can put the short end of a hex key in that cam plate hole to lock it for bolt tightening.
#
Maybe those steering head bearings had some form of Loctite but should have come out fairly easily if driven squarely. Replacements can be drawn in with two OEM Isolastic discs and threaded rod, bottom bearing seated first, then the top bearing drawn in until it seats on the inner spacer tube.

I have to say I can't remember the last PITA moment with bikes in general. If something is not going smoothly, stop and regroup.

Edit.
The large gearbox bearing seems to have a high interference fit even with the case heated so so wonder the case can crack between the two bores. I do not use cooling as it can also produce condensation the moment it gets near something hot, anything cooled would need wiping down before installation to at least minimise that.
I have seen Norton crankshaft main bearing pictures on FaceBook where it looked like they had been left outside the igloo for a month, they were grey !
 
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something else to think about. how many miles get put on most of matt's rebuilds? yes he does some nice work and my guess they get very few miles put on them so IMHO the 2RS would be fine for him but on a rider that gets plenty of use I will differ on his use of the 2RS.
 

L.A.B.

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And as for comments on the mainshaft bearing, i got that from CNW and asked Matt about the 2 RS bearing and he said that's what he uses, no problems. So that's what i'm going with

I would recomend to remove the inner side seal so it will receive a constant supply of lube and not relie on the grease that it came with. with the outer seal left in plece it will be less apt to flood the clutch release and oil find its way to the clutch but I would still use a clutch push rod seal.

I think perhaps TomU means the sleeve gear bearing (see gearbox photo) as that has a 'rubber' seal?

(Personally, I wouldn't use a seal either side of the mainshaft bearing because the lifter mechanism needs lubrication and wouldn't use one on the inside of the sleeve gear bearing either as the gear acts as a shield.)


Edit: Also
 
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Time Warp

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The photo looked straightforward even to me (I dismissed the pusher part)

I have no seals on that D/S bearing or any other.
There is a small gap at the teeth base/outer race ID that would allow oil to get to the bearing (eventually)

Running an outer seal might save the box losing its oil should the GB case seal fail, it might even be a barrier should chain lube/grit go the other way somehow and give the bearing some protection.
If the case oil seal and oil seal surface on the sleeve gear are fit for purpose it might be a moot point, the oil stays in, the bearings get oil.

It seems it can be run with one, two or no seals, one , two or no shields and still last.
 

TomU

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After reading up on doing the gearbox rebuild and watching Mick Hemmings video, i started the rebuild.

Sleeve Gear

IMG_2077sm.jpg


So far so good :)

Layshaft in with 3rd and 4th and Mainshaft in with 2nd & 3rd

IMG_2084sm.jpg


Still going good

2nd Lay

IMG_2088sm.jpg


Ok, this is fairly easy, just like in Mick Hemmings video :)

Then i started running into problems. 1st gear was a tight fit on the mainshaft. I thought i dry fitted it earlier and it went on no problem. Don't know why it wouldn't go on easily now. Anywho, since it doesn't float on the shaft like the other gears, i pounded it on. Was that a mistake?

1st gear pair

IMG_2095sm.jpg


And things didn't get any easier from here. I had checked the camplate timing by referencing the cam quadrant against the inner cover quadrant window. I set the timing for the same gap at the bottom (1st gear) and top of the window (4th gear). But with all the gears in, it wouldn't go into 4th. So rinse and repeat. Pulled everything out and tried again. Still no luck. Damn :mad:. Figured the timing's off, so pulled everything out and adjusted the camplate. I was able to get to 4th, but when i put the inner cover on, it was hitting the top of the window. Damn :mad:. After pulling the gears a couple more times and resetting the timing (and by that time i was getting good at taking the gears out and reinstalling, which wasn't super easy with half the gears firmly attached to both the lay and main shafts), i realized to get both 1st and 4th, the quadrant didn't line up equally on the top and bottom of the inner cover window. There was more of a gap at the bottom than at the top. I should have checked this before pulling the camplate to begin with.

Finally, i think i've got it right, but i am noticing some resistance going to 3rd unless i rotate the mainshaft. Is that normal?
 

grandpaul

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Remember that when installing the camplate and quadrant, they must be properly timed TO EACH OTHER before you can time the combo to the forks and gears!
 

TomU

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So, i think i've sorted the problem. At first i thought it was a bent selector fork shaft (which was brand new), but check it against the previous one, and another used one, they all have some deflection so i think that is normal. I then messed with the camplate again and when i put it back i think i did not have the o-ring fully seated to begin with so it was pushing on the camplate spindle enough to push the camplate slightly into the gearbox and binding the selector forks. I now have the o-ring over the camplate spindle correctly and that is enough to allow what i think is proper gear changes (it won't go through all the gears without rotating the mainshaft and holding the sleeve gear, but i believe this is normal)

Getting that sorted is a huge relief and now on the next issue, the layshaft end play. I measured around 6 hundreds slop and according to the Old Britts write up, i am supposed to shim on the kickstart shaft (Old Britts pic below).

Shims on the kickstart shaft.jpg

That essentially pushes the kickstart pawl out of the inner cover by the amount of the shim. With 6/100s to shim, i'm thinking that's a little excessive and am wondering whether to shim on both the kick start shaft as well as the layshaft after the 1st gear (just before the kickstart shaft). This would push the kickstart pawl out of the 1st gear by the amount of the shim. So by doing both, roughly 3/100 on the kickstart shaft and 3/100 on the layshaft, i'm moving the kicstart out by 3/100 and moving it out of the inner cover by 3/100s.

Has anyone done this (shimmed the layshaft)? Or any thoughts on doing this
 

mean gene

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I can't believe nobody told you to drain the engine case!!! Did you drain transmission oil? Oil that has been subject to weather changes and moisture form sulfuric acid, and causes steel to rust. You have seen the part covered with oil but rust underneath.
My opening remark would be to start drinking heavily and get all you tools out, Nortons use every faster in the book Whitworth, Metric and Us. Plus three or four thread pitches, DON'T mix them up.
Good luck there are a lot of friendly knowledgeable Norton people out there , Join a Norton Owners Group in your area and have fun!
 

Time Warp

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With used parts splined first gear will tend to go on smoothly in limited positions.
All you have to do with the cam plate/quadrant is install the detent plunger lightly and fit the other cover.
You can then check 1st and 4th in the cover window top to bottom, a case of go, no go.

Once you start pounding on things, stop, these gear boxes go together very easily.

I did two gearbox's the other week, one had 1.4 mm of end float, the other 0.8 mm, I elected to machine Al/Bronze heavy shims for a reduction to 0.25 mm /0.010")
Be mindful of the fillet radius on the kick shaft lifting that shim (if it is a non modified Isolastic shim)

The shift fork rod got sealer to the thread.

I also remove all the studs and countersink the holes so any raised surface (and there always is) around the stud does not compromise the gasket seal.
 
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