71 norton Primary installation

OK I bought a crank oil seal from the UK and it finally came in the other day, I put it in and am getting ready to install the Primary.

I also took some good advice and bought studs and nuts for the three mount points in the crank to primary. I have a new primary to crank seal too.


Do you guys have any tips for me going forward? Is there any write ups with detailed instructions with torque settings for these screws and shimming?

If you have anything please shoot me a line.


Thanks!


PS: How hard is it to do a 520 chain conversion? Do I need to replace the sprockets?

You'll have to grind down the stud and nut on the bottom one to keep the chain from hitting it. Make sure the holes in the crank are clean with acetone and use enough red locktite to install the studs. Use blue on the nuts. Use some rtv or your favorite sealant on the inner primary to crank gasket. Make sure the spacer on the center inner primary stud is correct and it does not bend the inner primary. Be careful torquing the studs and nuts, it's not real thick into the crank. If the torque settings are not at the old britts site, use the torque setting for that size nut.

Dave
69S

DogT said:

You'll have to grind down the stud and nut on the bottom one to keep the chain from hitting it. Make sure the holes in the crank are clean with acetone and use enough red locktite to install the studs. Use blue on the nuts. Use some rtv or your favorite sealant on the inner primary to crank gasket. Make sure the spacer on the center inner primary stud is correct and it does not bend the inner primary. Be careful torquing the studs and nuts, it's not real thick into the crank. If the torque settings are not at the old britts site, use the torque setting for that size nut.

Dave
69S

Click to expand...

Thanks for the tips! Ill look for the original torque settings online. I think I saw the monual somewhere. Do you know the exact thickness of that spacer for center inner primary? I dont know if the one I have is correct.... Regular red loctite is good and will seal those threads nicely?

Old Brits has assembly text/photo's and factory manual says just reverse the tear down process : )

Be alert not to have too much cold tension in triplex chain or bad drivetrain juju once full hot tensioned. Ya can bash on the stator laminates a fair bit to fine tune the rotor clearance but may need to wallow out the holes to get clear all around. Important to get gearbox pretty square for chain run but don't need prefection in chains like a belt does. The sealing rubber may need a bit of back fill with RTV to be proud enough to seal. I like AFT type F if not Electro start.

520 convert - buy Atlas sprocket and mill DS drum teeth off to .240" thick and start shopping for next drum and sprocket if you take much advantage of full torque like I did till seeing the light on my economics of fanned over sprocket teeth in 19 to 20 count. A 530 X-ring will fit w/o any mods but for some bikes a short time of noise till a non issue path cut. A regular power Cdo may not have such teeth decay issues though.

hobot said:

Old Brits has assembly text/photo's and factory manual says just reverse the tear down process : )

Be alert not to have too much cold tension in triplex chain or bad drivetrain juju once full hot tensioned. Ya can bash on the stator laminates a fair bit to fine tune the rotor clearance but may need to wallow out the holes to get clear all around. Important to get gearbox pretty square for chain run but don't need prefection in chains like a belt does. The sealing rubber may need a bit of back fill with RTV to be proud enough to seal. I like AFT type F if not Electro start.

520 convert - buy Atlas sprocket and mill DS drum teeth off to .240" thick and start shopping for next drum and sprocket if you take much advantage of full torque like I did till seeing the light on my economics of fanned over sprocket teeth in 19 to 20 count. A 530 X-ring will fit w/o any mods but for some bikes a short time of noise till a non issue path cut. A regular power Cdo may not have such teeth decay issues though.

Click to expand...

So I can just throw a 530 on there? If so I will go pick one up. Im not worried about the weight diff.... I managed to stretch a 530x on my sportbike (130hp) heh dont think the norton will do that.

Yes over a decade of rider reports on just slapping a 530 X-ring on gave 50/50 chance it ran clear right off or only took a little non structural groove out of cases before running free. O-ring are a bit too wide and a lot too stiff compared, so O=Obsolete.

Don't compare wimpy torque hits hi rpm sports bike loads on teeth to a SNorton. My 70 hp 42 tq SV650 wears out thin Al teeth d/t the grit but did not fan over the teeth -just wore em to nubbins the chain would ride over noisey going no where. My Ms Peel flat fanned them over before much pointy wear at tips but deal breaker was drum teeth wore to chain sliding nubbins in couple 1000 miles... Back then Peel was a sports bike hunter eater and I was exploring her performance envelope beyond that on almost every ride for about a years worth - till over rev event took her power down. May not be an issue on lessor steeds and saner use.

Chains do not stretch, only wear via plate holes/pins wallowed out. Check chain wear by lift out of back of drum valleys to see where chain rides at speed to judge the time for a new chain. I get timid on throttle use at 1/3 lift out and prep for a new chain or have ignored throttle control and waited a bit more to also shop for new teeth in 1/4" or 3/8" widths.

If you NEED a new rear drive chain then just get the standard replacement and be done with it

Its all you will ever need unless you are racing


Otherwise, you are taking the risk of a "modern" O ring type chain scraping the inner primary cover

nah I dont think I "need" chain or sprocket. Just thinking of possible things to replace while the primary is off. excuses to spend money i guess


Ill run with the advice to replace when I need to and with the standard chain... The chain and sprockets look pretty good now.

Thanks

iceteanolemon said:

Do you know the exact thickness of that spacer for center inner primary? I dont know if the one I have is correct.... Regular red loctite is good and will seal those threads nicely?

Click to expand...

The spacer is a custom fit. They are all different. Install the inner primary with gasket and measure the space, then fill it up with a washer/washers. It's a double job. If you get enough locktite it should seal, but I also stuffed a bit of rtv under the nuts when I put them on, just for drill.

Dave
69S

ok, I will try and do the best at measuring. Maybe I will place the primary on then see if I can slide feeler guages in or something. Then get the right fit.

Just slide various washers in there along with the feeler gauge and you can figure it out. The factory washers may not be precise, just get it as close as you can. If need be, you can grind or sand washers down.

Dave
69S

ok i slid on washers and got the primary to be level with everything. the primary is defeintely flat with the crank.

new crank oil seal (rubber covered one, took freaking 15 days to get here!)
new crank to primary seal (thin coat of permatex hitemp orange)
replaced mounting bolts with studs (red loctite on crank side)
ground down the bottom rear stud and bolt to avoind chain interference


I have everything on finger tight right now and waiting to fully seat the mounting studs after the permatex cures a little.

Hopefully it all goes together well and I am not left with a bunch of parts afterwards!!!

iceteanolemon said:

ok i slid on washers and got the primary to be level with everything. the primary is definitely flat with the crank.

Click to expand...

This is a key procedure. Well done! Overlook and underestimated by many. This will go far to help with drive chain clearance and a dry area under the primary case.

now I am looking at the spacers and washers I have and trying to piece em together. Anyone have pics of how these go?


I think I have the ones right that are behind the clutch basket.

I am getting confused with the ones in front of the forward primary sprocket.

Clutch:
Clutch locating circlip
Clutch locating washer (cup over circlip)
shim to true up clutch hub to the front sprocket.

Front sprocket:
Sprocket on crank,
shims so the alt spacer/washer and subsequent rotor will seat the front sprocket to crank taper.

Note. sometimes the end of the crank taper will stick out past the sprocket and if not shimmed, will not get the push from the rotor and rotor nut. It will rattle and be difficult if not impossible to time, eventually shearing the key.

pv's got it just right, but to re-iterate.

Crank drive. Sprocket, then washers and a shouldered thick washer with the cut out facing outside. It lets the key seat completely, if you put the cut out facing in, the key and rotor won't seat.



Clutch. circlip, use a new one or I think pv said to use a circlip from the e-start. Then the cut out washer with cut out covering the circlip, and then spacers to align the primary chain, I had 2. Don't tighten to 70 ft. lb., use blue locktite and 40 ft. lb. You can break that circlip.

At this point you may want to look up behind the inner cover and see what the clearance is between the left swing arm end and the primary chain case. It shouldn't be touching, but may be close. Here's mine, maybe 1/8-3/16"?



Cool shot, eh? Used the coolpix upside down sitting on the chain.

Make sure you have the spacer correct for the gearbox top bolt. It goes between the cradle and the gearbox, lots of times it gets left out and then you will loose that space from the swing arm left end to the primary inner.



What's that red stuff?

Dave
69S

DogT said:

pv's got it just right, but to re-iterate.

Dave
69S

Click to expand...

Is that not a double cupped spacer. One side will fit over the crank end and against the shims, the other side goes toward the rotor.

awesome tips. I will check that clearance right now!

My swingarm is super close but its not touching.


I got no clue what that red stuff is. I guess the P.O. thought it would be snazzy to paint the inside with it? I have a pretty stylish inner primary.

pvisseriii said:

Note. sometimes the end of the crank taper will stick out past the sprocket and if not shimmed, will not get the push from the rotor and rotor nut. It will rattle and be difficult if not impossible to time, eventually shearing the key.

Click to expand...

your scaring the crap out of me.


Your guys tips are definitely paying off for me. I appreciate it.

iceteanolemon said:

pvisseriii said:

Note. sometimes the end of the crank taper will stick out past the sprocket and if not shimmed, will not get the push from the rotor and rotor nut. It will rattle and be difficult if not impossible to time, eventually shearing the key.

Click to expand...

your scaring the crap out of me.


Your guys tips are definitely paying off for me. I appreciate it.

Click to expand...

Don,t mean to scare you. Just put that rotor spacer on the correct way so you know that the rotor will seat the sprocket when assembled.