Interstate Cafe

Discussion in 'Some Assembly Required' started by DavAmb, Aug 24, 2021.

  1. DavAmb

    DavAmb Been here awhile

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    Bit over 2 years now since the Norton Cafe ceased to be rideable. During this time, I've managed to make a quite decent recovery and have resumed riding. And after buying it in pieces some 30 years back and spending most of that time fiddling and fettling I've finally reduced the wreck back into several boxes of parts.

    The frame is beyond repair, so what's left could hardly be called a bike any more. To this end, a friend told me of a local chappy who had some Norton bits and it might be worth getting in contact to see if he had anything I could use. Well, what he had turned out to be too good for parts, so I ended up with another Norton project, a red 850 Interstate. The motor had been removed and stripped after a seize, everything damaged repaired or replaced but not re-assembled; the owner had too many other engineering projects on the go.

    This is the Interstate:
    IMG_0926_01.jpg IMG_0927_01.jpg
    So I've got 2 Norton projects on the go, re-assemble to 850 motor and get the Interstate going and see if I can resurrect the Cafe.

    I'll bung some progress notes, pix and schtuff here as I go.
    #1
  2. DavAmb

    DavAmb Been here awhile

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    Bench set up and engine support box/frame thingies built.

    IMG_1233.JPG IMG_1234.JPG

    Need to split the crankshaft and check/clean the sludge trap. That requires new studs and nuts so no bottom-up build, it's top-down instead.
    Started with the head. No valve spring compressor, so used the drill press instead:

    IMG_1238.JPG IMG_1239.JPG

    Assembled in one rocker and shaft, but can't rotate the rocker's shaft to align with the oil feed - it's a really tight fit in the head. Might have to see if I can extract it and try again. Something not right there. Bummer. Won't do the other 3 until I know what's dodgy here.

    I'll get the crank studs/nuts ordered. Should have the bits in a week. Think I've got everything else.
    #2
  3. huub

    huub Been here awhile

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    nice project!
    i'll be following this.
    my 750 combat has been waiting for a rebuild for the last 25 years....
    #3
  4. DavAmb

    DavAmb Been here awhile

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    Y'know that the parts from a dormant rebuild project have a half-life Huub? The longer you leave the bits in storage, the more that bits will go astray!
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  5. DavAmb

    DavAmb Been here awhile

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    Episode 3: Shafted.

    If the boys on Project Binky can have eps, then so can I.
    Today I managed to get the rocker shaft out. Thanks to the differential thermal expansion rate of Aluminium being almost double that of steel, then the oven was my friend.
    Also made up a puller to drag the warm bits out. Great on a friggin' cold day to work on warm equipment.

    IMG_1240.JPG

    Once the shaft was out I oriented it correctly and drove it carefully back in, maintaining the orientation (oil flat away from the centre of the head in case you want to know).
    Couple of hours later the 850 head was complete:

    IMG_1243.JPG

    No gaskets at this stage, I've got a complete engine kit, but will do that all in one go later on.
    I've ordered new studs and nuts for the crank clean-up but that'll still be a week away.
    In the meantime, I thought I'd rip the head off the 750 engine and see what there is in the way of damage.

    IMG_1241.JPG

    Well... nothing really. A cracked fin on the barrel - not sure if that was me being stupid or a legacy of the accident or both. Should be able to get it brazed back on I hope.
    Thought the vernier isolastics survived the stack, but a closer look at the front one shows it didn't fare so well. Might be only the main tube, will strip it down and see what can be salvaged there.

    IMG_1242.JPG

    I stripped the head of valve gear and any usable parts and called it quits for the day.
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  6. t205

    t205 n00b

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    Will watch with interest Dave, have you had any more thoughts on where the 750 engine might end up?
    #6
  7. DavAmb

    DavAmb Been here awhile

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    Episode 4: The man with 2 heads.

    Hey T2,
    at this stage - on my coffee table. I've still no idea on what I'll do frame-wise. Until then I'll just plod on. Could make a take-no-prisoners mobility scooter?
    Brother reckons he can TIG up the broken fin. Just have to wait for the lockdown to end. That or pay a fortune to have it shipped up to him in town. It'll keep.

    65174250314__3F6ECECA-319C-48A8-AC22-F15B8EE27460.JPG

    I dragged out my FullAuto head.

    IMG_1244.JPG IMG_1245.JPG

    Bought this over 2 years back and intended to fit it then. Just as well that I hadn't really.
    Had to relieve the old head of its studs and fasteners so chucked it in the dishwasher to preheat and clean.

    IMG_1246.JPG

    Does a great job. Good thing madam is up in town huh. Oil from cooking utensils or from mech bits - what's the diff? Dishwasher doesn't mind.
    Should have this assembled in a day or two. The old head had new valves not that long ago and they're still a snug fit in the new valve guides. Lap them in and recycle the rockers and springs and good to go.

    IMG_1248.JPG
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  8. DavAmb

    DavAmb Been here awhile

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    Episode 4.5: Fractional Progress

    Not enough to warrant a full milestone, but stuff is still ticking along.
    Whipped of the 750 barrels and cleaned them ready to drop off to my bro to see if he can weld the busted fin back on.
    Everything very nice under the bonnet on this motor. Fair whack of carbon build-up on the piston faces but skirts and bores and cam and follower faces show zero signs of wear. Will clean up nicely. Won't strip this motor down any further - apart from checking the oil pump and ancillaries.

    IMG_1262.JPG

    Found all the fasteners for the 850 and was impressed to find they'd all been zinc plated:

    IMG_1265.JPG

    Decided to look into this and have decided to do the same with my bits. I've bought some zinc anodes and containers and other bits, just need 8 litres of vinegar and some epsom salts. Then these blighters for the 750 will gain some bling:

    IMG_1263.JPG

    The new crank fasteners have turned up, so no excuse for delaying pulling the 850 crank down to check the sludge trap now.

    IMG_1266.JPG

    I've also put together a torque wrench. This is a steel tube with a welded-up 1/2-inch drive jammed in one end and a digital fishing scale at precisely a half-metre away (need to make sure the pull is at right-angles to the tube and double the pull for kg.m):

    IMG_1267.JPG

    Need a better way to hold the valves for grinding them to fit the new seats in the FullAuto head. The classic suction-tipped rubber stick thingies are useless. Magnets I thought. Nope, totally non-magnetic valves. Thinking of gluing the valves to suitable sticks.
    Anybody got any tricks for holding valves?
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  9. VX Rider

    VX Rider Long timer

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    will they chuck up in a drill?
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  10. DavAmb

    DavAmb Been here awhile

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    You mean grab the valve from the stem side VX? If so, yeah, that might be a goer. I could use the tailstock chuck off the lathe. Heavy little tool that though, but might do the trick. Otherwise I may be able to take the chuck out of the drillpress. If I've misunderstood - please explain further. I'll also look at adhesives, I'm sure I could remove any residue from the valves. Maybe just common-or-garden hot melt will work.
    #10
  11. adam728

    adam728 Long timer

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    One trick is to insert the valve in the head, and push a piece of fuel line, tygon, etc over the stem. Chuck a cordless drill to grab the hose. Might have to shove a bit in the hose, then have the chuck tighten over the hose and bit so it'll grip. Leave a few inches between drill and valve stem as a flexible connection.

    The idea is you can spin the valve for lapping, and pull a littlw bit on the drill/hose to change the force between valve and seat. But you can't side load or cant the valve, which would lead to a bad lap job.
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  12. VX Rider

    VX Rider Long timer

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    Yep, use the stem
    Maybe a strip of rubber as a buffer between the chuck and the stem to prevent damage to the stem
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  13. DavAmb

    DavAmb Been here awhile

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    Ok, thanks guys, I'm with you now - sounds like the way ahead. Will give it a go and report back in a couple of days.
    #13
  14. DavAmb

    DavAmb Been here awhile

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    Episode 5: Two Heads are Better...

    I've been doing other stuff out in the garage, but have finally come back to the Norton(s).
    I put together the zinc plating line and the results were great.

    IMG_1283.JPG

    I've not bothered to clean these up after plating, so the result isn't as good as it could be, but I'm after function here above all.
    I also did an old wrench of my dad's as an exercise to see what could be achieved if you want to put the effort in.
    Before:

    IMG_1288.JPG

    After:

    IMG_1290.JPG

    The end result is directly proportional to the effort put in - plenty of prep with the wire wheel, a brush with phosphoric and a bit of a swim in hydrochloric before plating and then another session with a soft wire brush after.

    I found that a glob (is that a metric or imperial unit of measure) of blutak did the job of holding the valve to the lapping tool and all the valves lapped-in ok on the FullAuto head. Now both heads are complete:

    IMG_1310.JPG

    Am hoping to get the 750 barrels back by the weekend then nothing is stopping me from putting the 750 engine back together.
    And no excuse for not pulling down the 850 crank either, just been a bit slack huh.
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  15. Peculierboy

    Peculierboy Adventurer

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    Love it. Fullauto head? Totally jealous....I'm in the process of rebuilding the top end of my '74 850 right now and getting the exhaust threads repaired, etc. Huge bummer, just got the cylinder back from the machinist and in the shipping process, a fin was cracked off, so back it goes to get fixed. <sigh>

    Good luck with your project!
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  16. DavAmb

    DavAmb Been here awhile

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    Episode 6: One Down, One to Go

    750 motor is now assembled with the repaired and painted barrel and new head. New gaskets throughout. Maybe it'll be a bit less of a sieve this time around.
    Didn't even bother trying to engage barrels on pistons manually, the cast iron barrels are just waaaay too heavy. Maybe with two people it might be possible, but I decided what was needed was a skyhook, so suspended the barrels over the pistons and then used a turnbuckle to lower it with some measure of precision. Was easily able to engage the piston rings in the bores with just my fingers:

    IMG_1333.JPG IMG_1334.JPG IMG_1335.JPG

    Chucked the head on just to have a look, but did this knowing I would still have to remove it again to fit the nuts on the barrel threads:

    IMG_1336.JPG

    The bit on the top is a Dave Taylor headsteady. It's made out of a couple of rose joints and constrains the engine to only move backwards and forwards on its isolastics. Result being tighter handling as the rear swingarm is mounted on the engine/transmission subframe.

    Then I wondered if there was some way I could mount an oil cooler directly to the engine and then not have to worry about coupling issues if it was frame mounted:

    IMG_1338.JPG

    Hmmm... dunno. Needs more thought.

    Whipped the head back off and was about to fit the pushrods when I noticed some marks on the two inlets:

    IMG_1337.JPG

    Chucked the lot in the lathe and did a bit of a tidy-up with fine wet-and-dry:

    IMG_1339.JPG

    So that's about it for this motor. I'll tidy it all up and check the cam / oil pump chain and replace what gaskets and seals I can get to.
    Feel confident now to start putting the 850 engine back together now. Hopefully I can pick up the roller in a week.

    I'm still hoping to find a replacement frame. This one came up recently
    https://www.ebay.com.au/itm/Norton-750-850-Commando-Frame-2305-/373740267223?mkpid=0&emsid=e11010.m1951.l7534&mkcid=7&ch=osgood&euid=ffabe0a21df847ec908424f8c19b0d3a&bu=44868342194&ut=RU&osub=-1~1&crd=20211007172203&segname=11010&sojTags=ch=ch,bu=bu,ut=ut,osub=osub,crd=crd,segname=segname,chnl=mkcid&nma=true&si=9PIy6T5QbqgeMIFtbUn%2Bg06YufU%3D&orig_cvip=true&nordt=true&rt=nc&_trksid=p2047675.l2557
    But our dollar is shit against the U$ and I'm skint! Throw in another $250 for shipping and there'd be no change out of a grand.
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  17. Peculierboy

    Peculierboy Adventurer

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    I like the skyhook idea. I put the pistons in the cylinder first, on the bench, and then slide the cylinder on the studs, attaching the wrist pins in. Check out

    I don't use sockets, I made spacers using PVC pipe instead.

    Also, CNW makes some base studs that are shorter, so you don't have to lift the cylinder again to get the nuts on, and the nuts are 12 point as well. https://coloradonortonworks.net/cnw-barrel-kit-for-750-and-850.html
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  18. DavAmb

    DavAmb Been here awhile

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    Nice work sir! Another pair of hands sure makes it easier, but I didn't have that choice. Yeah, lifting the barrel is a right pain. That and getting the pushrods to engage properly, but it all comes together in the end. I used a couple of sticks (like chopsticks in form-factor, but made from jarrah offcuts) to support the pistons on their conrods while engaging the barrels. You don't want a nick in either of the rods - it'd have to be polished out. (I like the Jerry Doe tee-shirt in the vid, I'm Davamb over there too.)

    edit:
    Oh and doesn't the motor in the vid have a timed breather? No point in the XS reed valve if so yeah?
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  19. Peculierboy

    Peculierboy Adventurer

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    That's not my vid, shamelessly stolen off the interwebs. But it is from a fellow Access Norton member, Swooshdave.
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  20. DavAmb

    DavAmb Been here awhile

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    Cheers PBoy, ah yeah, the mighty SwooshDave. Didn't spot that it was him. Interesting to note the use of sealant brushed on to the barrel base gasket. I've not added anything to this gasket, wasn't aware that it was prudent to do so. Thoughts or comments?

    I finally collected the 850 roller yesterday. Tempted to chuck the 750 motor in it to see how it goes, but s'pose it'll keep. Added incentive to crack on and reassemble the 850 motor:

    IMG_1343.JPG IMG_1344.JPG
    #20
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