1972 Roadster Rebuild - 750 Combat

grandpaul said:
I beg to differ...

"BEFORE"
1972 Roadster Rebuild - 750 Combat


"AFTER"
1972 Roadster Rebuild - 750 Combat
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Those parts sparkle. I'm glad you "differed"with me. I thought I had gotten my info from a reliable source. However looking at your before and after pictures has me rethinking.
 
My polishing guy,just sent pics of my parts..........
 

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gortnipper said:
http://www.raydobbins.com/polishing/Polishing_Guide.pdf
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I'm running into issues polishing the brake caliper. The grey compound is sticking and clumping on the surface of the caliper. This clumping prevents the cutting.

What I did to resolve the problem is clean the buffing wheel with the spur tool. I was thinking maybe the wheel was dirty and contaminated from previous jobs. I ran the spur wheel and dressed the wheel with grey compound. This did nothing. As soon as touched the caliper to the wheel the compound clumped on to the surface again.


I'm thinking I may have bad compound,(unlikely), or the caliper is too cold, (temperature) and needs to be warmed up before cutting will take place.

As far as pressure, I'm applying very little pressure and gradually increasing pressure.

I experimented by applying compound and immediatedly applying heavy pressure. Still the compound clumps.

Any thoughts?
 
You need heat, through friction, to melt the compound.

You also need the right amount of compound, too little and it won’t polish, too much and it will clump and streak on the alloy.

A frustratingly tricky process until you’ve got the knack!
 
Fast Eddie said:
You need heat, through friction, to melt the compound.

You also need the right amount of compound, too little and it won’t polish, too much and it will clump and streak on the alloy.

A frustratingly tricky process until you’ve got the knack!
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Thanks fast Eddie. That is exactly what is happening. The compound is streaking and clumping on the alloy. And Im pretty sure it's because of lack of heat. My garage temp at the time was probably 45 degrees give or take.

The alloy is too cold. I'll bring the alloy in the house to warm up. (Maybe keep it on the woodstove hearth). Then make another go at it.

I have some other metric bike alloys I can practice on.

I did the front wheel hub earlier this summer and it turned out well. Rather quick and painless. Heat.....

1972 Roadster Rebuild - 750 Combat


However, I need er polished it with a loose flannel wheel to give it that deep luster shine. Next time the wheels apart it will get polished again.
 
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1972 Roadster Rebuild - 750 Combat


This is what I'm considering before pic of the alloys. Seems I'm missing something tho. Grandpaul had some smaller alloy bits in his pic.
 
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Fast Eddie said:
You need heat, through friction, to melt the compound.

You also need the right amount of compound, too little and it won’t polish, too much and it will clump and streak on the alloy.

A frustratingly tricky process until you’ve got the knack!
Click to expand...

"You need heat, through friction, tomelt the compound."

I get that I need heat from friction and is partp of the process. Getting the alloy heated is tricky.

Pressing and Holding alloy to the wheel with or without compound with eventually create the needed heat.
I just don't want to cause damage to the alloy and or wheel while bringing it up to temp.

But I suppose the wheel isn't cutting until the alloy is brought up to temp and compound applied. So probably holding the alloy to the wheel is the way to go.

I won't polish anymore until I have gotten more advice fromfthise more experienced than I.

Shining/buffing metal is an area of interest to me. It's dirty fun.
 
Today I took some pics of the engine components (Head and valves, crankshaft, rocker arms, and bearings, swingarm spindles, casings). Also, a picture of the new swingarm spindle.

The head and valves, Not too bad. Turned out pretty clean. Maybe someone can share with me. Do some people put clear finish on the heads? Seems like CNW bikes have a spray finish on the engines.

1972 Roadster Rebuild - 750 Combat



A close up. I put sandpaper on the drill press table and run the head across it several times. Very little warpage. Plenty of pin sized pits. No biggy


1972 Roadster Rebuild - 750 Combat



The three spindles. The new one comes with the slots. Im still debating whether or not to do the spindle upgrade.


1972 Roadster Rebuild - 750 Combat



I've been reading old brits and VHT SP117 seems to be the color of choice for the cases. Today I taped the cases. Waiting for a warmer day to paint them.


1972 Roadster Rebuild - 750 Combat


1972 Roadster Rebuild - 750 Combat
 
And last but not least is the crankcase. I find it unique how Norton put the lobes of the crankshaft on parallel with each other.
Tomorrow I will be tearing into the crankshaft and cleaning it up. I will also get the gasket kit 0ordered tomorrow.
The jug (no picture) has been lightly sandblasted. It will need to be bored as some deep rust pits have accumulated since sitting so long.
I'll try to get some pics of it.
What product is used to paint the jug black? Rust-Oleum gloss black?



1972 Roadster Rebuild - 750 Combat
 
Re the spindle upgrade:

the late model spindle with the 2 flat spots is used with the late model engine cradle, which has to dual wedge bolt fixing mechanism, so you need the proper cradle to use that spindle.

If you use the engine cradle with the single bolt swingarm tube, you can do the kegler clamp modification to bring it up to late model performance specs. You can buy the clamps from NYC norton already to go. (I made my own some years ago and it cured my bike's snake like handling. I think it's a must-do for bikes with the early single bolt swingarm tube.
 
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