850 MK3 Finally coming back together........

JOHNO23

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Following on from my thread asking for ideas on upgrades etc, I have now started the strip down and refurb of my Mk3.I will post pics up here as I move along the process.Please any advice is very welcome as I haven’t done one of these before!
The bike has been sat in my garage for about 10 years. It was running prior to that, but very poorly. I initially thought it was worn carbs, but someone on here suggested I check the valve lift as MK3’s were known for having very soft cams. This proved to be the problem. 3 of the 4 valves barely opened at all, I have no idea how the bloody thing actually started, but it did!!

Anyway, you can see below where I have got to on day 1. I’m guessing I now need to get the engine out . I am going to remove everything on the bike and probably powder coat the frame and other bits. The electrics look really bad with all sorts of crap connectors and wires every where. I will be fitting new electronic ignition and probably dynamic coils or equivalent plus modern rectifier/regulator. Would I be better having a new harness made up for this rather than getting a stock one off the shelf?
As I was saying please please don’t be afraid to pitch in with advice or comments regarding what I’m doing whether it be right or wrong.I need all the help I can get.

Thanks in advance guys, this place is a fantastic source of information and inspiration.

Bollocks! How do I add pics on here? Can someone advise please.......
 
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Richard Tool

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I had the same problem loading photos when I first joined - you need a photo hosting site such as Imageshack, Photobucket etc or join as VIP member which allows direct linking of your photos
 

JOHNO23

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I had the same problem loading photos when I first joined - you need a photo hosting site such as Imageshack, Photobucket etc or join as VIP member which allows direct linking of your photos
Thanks, I have now gone VIP.
 

Richard Tool

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Can I ask, why?
Not to answer for batrider but my minimal experience with powdercoat has been negative. Like many process’ the quality of the job is dependent on the skill/contentiousness of the person doing the work. I had to buy a new main frame for my Commando due to rust issues- it came from Andover with a powdercoat finish and it is a beautiful job . As I had media blasted the remaining chassis components I thought that I should have them powdercoated to match . Andover supplied me with the code for the powder and I took them to a powdercoat shop to be done .
Sadly the quality was all over the map - some pieces nice , some mediocre and some terrible. I have since learned that the quality will vary depending on where in the oven the pieces are placed and how many are placed in the oven. Powdercoat is difficult to strip off to do over . Fortunately it can be blocked and rubbed out but the risk of breaking through is there just as in paint . I was able to save some of my pieces this way but others had to painted over so more $$ . Fortunately it can be painted over . I am told by some that powdercoat can trap moisture beneath and thus cause corrosion. It is also VERY difficult to touch up if it gets damaged.
I imagine there are competent people out there who do very good work with it but I, unfortunately, did not receive a good job.
I will stick with paint from now on .
 
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Paint is also a quick fix up if you possess an air brush, or just use a rattle can.
 
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Once water gets under the powdercoat it is all over. It will peel off in large pieces.
I did have some smaller pieces like fender stays and airbox front cover powdercoated with the gray/silver and so far so good for the past 10 years. But to me a powdercoated frame looks plastic coated and the black is not black enough. The local sandblast place here (Blastco) uses a 2 part epoxy primer and then a black urethane paint. This combo has worked well on my previously powdercoated trailer hitch.
Russ
 

grandpaul

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As long as you employ a reputable powdercoater who is detail-oriented in the prep and masking phases, you'll be fine.

I've done over 60 restorations, refurbs and custom builds that ALL used powdercoating by known professionals, masked all critical points correctly (after the first incorrectly masked Commando, sorry), and after 15 years since the first one, I have received a total of ZERO negative reports regarding powdercoat finish or performance.

All you need to know about prep and masking is here: http://www.oldbritts.com/powder_coating.html

The durability of a good powdercoat job is unrivaled by paint. Also, you can perform simple touchups in the event of welding or mods in the future by simply masking and spraying with Rust-O-Leum glossy black.

My first (and only) incorrectly masked Commando was fixed by carefully grinding the offending overcoated areas with a dremel sanding drum. Well, several dozen sanding drums...
 

Fast Eddie

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As long as you employ a reputable powdercoater who is detail-oriented in the prep and masking phases, you'll be fine...
I’m inclined to agree GP, but therein lies the problem... how do you know? Finding out by getting your parts done is a real bummer if they’re not as good as you thought. I went to a highly recommended place, but I clearly got the new boy, or whatever!

In theory it may be good. In practice it’s far easier to get a good paint job done.

Yes powder is tough, it’s ideal for dirt bikes... thus unless folk are putting their Commandos on the dirt, paint will likely suffice...
 

JOHNO23

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Perhaps I’ll paint it:).......or not...:D

Any thoughts on the wiring issue?
 

gortnipper

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The electrics look really bad with all sorts of crap connectors and wires every where. I will be fitting new electronic ignition and probably dynamic coils or equivalent plus modern rectifier/regulator. Would I be better having a new harness made up for this rather than getting a stock one off the shelf?
All of these will work with a stock harness, which is fairly easily modified. (I deleted the Interpol wiring from mine)

It depends probably on what other modifications you are planning and how good you are with electrics?

If you are neither going to do any other substantial electrical mods (like convert to -/earth or add/delete lots of other stuff) nor if you can read a schematic and make one up yourself (which "having a new harness made up for this" seems to belie), then it would probably be best moving forward to use an off the shelf harness, so you and others have a common understanding in the future.
 

JOHNO23

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All of these will work with a stock harness, which is fairly easily modified. (I deleted the Interpol wiring from mine)

It depends probably on what other modifications you are planning and how good you are with electrics?

If you are neither going to do any other substantial electrical mods (like convert to -/earth or add/delete lots of other stuff) nor if you can read a schematic and make one up yourself (which "having a new harness made up for this" seems to belie), then it would probably be best moving forward to use an off the shelf harness, so you and others have a common understanding in the future.
Thanks gortnipper,
The only other mod I may do is upgrade the alternator.
What if anything, is the advantage of changing to negative earth?

I’m m not great with electrics,I can follow the wiring diagrams fairly easily but not much more.:rolleyes:
 

gortnipper

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Thanks gortnipper,
The only other mod I may do is upgrade the alternator.
What if anything, is the advantage of changing to negative earth?

I’m m not great with electrics,I can follow the wiring diagrams fairly easily but not much more.:rolleyes:
You can use a wider range of electrical mods not made for Nortons.
 

L.A.B.

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I will be fitting new electronic ignition and probably dynamic coils or equivalent plus modern rectifier/regulator. Would I be better having a new harness made up for this rather than getting a stock one off the shelf?
Having one "made up" is likely to be expensive and for what you are thinking of doing it isn't necessary.
Not sure what you mean by "dynamic coils"? Do you mean 'Dyna' dual coil?

Adding a modern reg/rec and a three-phase stator should be no problem.

The Mk3 'harness' is made in sections, so 'main', 'headlamp', 'console', etc, and as you have electronic ignition then you don't need the 'ignition' sub-section.
The AN main harness section now comes with bullet connectors instead of the ignition sub-harness multi-plug (and console section plug) so electronic ignition can be fitted without having to cut the plug off.

https://andover-norton.co.uk/en/shop-details/20591

There are no Interpol wires in the Mk3 harness.

Edit: AN's headlamp harness section also comes with bullets instead of 'AMP' multi-pin plugs so modification (cutting plugs off) could be required although the headlamp harness section with plugs can be obtained from other suppliers.
https://andover-norton.co.uk/en/shop-details/20590
 
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I’m inclined to agree GP, but therein lies the problem... how do you know? Finding out by getting your parts done is a real bummer if they’re not as good as you thought. I went to a highly recommended place, but I clearly got the new boy, or whatever!

In theory it may be good. In practice it’s far easier to get a good paint job done.
Does the powdercoater prime it first? A lot say this is not necessary. I don’t agree, and chap in UK who did an alloy wheel for me agreed that it should be primed. I suspect this would also help with stopping rust if chipped.
 
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Fast Eddie

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Mine doesn’t appear to have any prime under it that I could see when I ground it off in the various fixing points.

I’m no paint boffin, but given how well it sticks, and how awfully difficult it is to strip when you want to remove it, I’d say a primer isn’t necessary.

The rust issue isn’t normally about chipping. It’s normally caused because the powder crushes when surfaces are bolted together, then moisture gets in underneath and rather than lift the paint and show itself, as it would with paint, it just stays there eating away at the metal.

To prevent the crushing, people either mask off before coating, or grind off afterwards, then apply a thin coat of paint. Whilst this prevents the crushing and resultant loose fastener issues, it still leaves a very vulnerable weak spot whereby water / rust could gain access and creep under the powder.

Most primers (as far as I know) wouldn’t defend against this, they’re designed to aid adhesion, not prevent against rust, and are actually porous.
 

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