Matchless G-15CS...Get it Running!

Hi everyone—just starting my own thread on my G-15CS. Picked the bike up a year ago from the original owner here in the USA, but owing to work travel haven’t touched it till now. Unfortunately, I’m still in transition and won’t be able to dedicate a ton of time to it…I’ll be living about 6 hours from where the bike will be for a while. The bike has been a rider its whole life, not a show piece. It has a basic solid red re-paint job and a few subtle mods. It ran when parked… For now, my goal is simply to get the engine running and the bike rolling. Once that’s done, I’ll see what else wants attention. Fork probably needs a rebuild, and there’s lots of peeling chrome.

I’m new to Nortons, and am not a particularly experienced mechanic, but do have some experience with an Enfield. (The Matchless owner offered me the bike because he saw my tolerance for that thing’s shenanigans…luckily it runs pretty well now after some extensive chassis and engine work.) Appreciate the chance to get input from the board here…gonna need it all.

As obtained:










The Ceriani shocks are probably no longer tip-top; guessing a new set of Hagons will be in order once it’s running.



I’m told this is a home-made Zener diode…bike also has no battery, just an electrolytic capacitor. Used one on the Enfield for a while and it worked OK, but I preferred the cap as the backup for a proper battery. We’ll see what happens with that.





I checked and replaced all fluids and tried to fire it up, but I had no spark. So off came the rather obstinate timing cover, and I got the magneto detached and sent for service plus an EasyCap installation. Realized the petcocks were gummed up, so I figured the carbs might need a look too. Found them clean as a whistle, but the slide/barrel fit was terrible, so I sent them for re-sleeving and got new gaskets and needles/jets, since the needle jet orifices looked a little out of shape too.

Went to put the mag back on, so I had to get the primary cover off in preparation to time it. (Fun time with the left footrest…ugh…)

And now it sits like this in the driveway




Clutch operation had been heavy, so I took the clutch down to inspect. Plates are fine, but the hub was pretty chewed up



and the pressure plate pushrod adjuster ended up stripping out…investigating that led me to find the pushrod seemed a few mm too long (thanks for the help on the board here) so the correct Atlas clutch pushrod is now on order with the pressure plate and hub.

(Adjuster seemed a bit far out from the plate even when bottomed.)



(Then this happened.)


Plus a new Venhill cable, and I hope the clutch operation will improve substantially.

Timing side sits waiting for a new triangular gasket for the magneto and a cover gasket. I dread re-fitting the cover, though.

Do make sure that you fit a new conical rubber oil seal on the oil pump when you fit back the timing cover, it is absent in this photo, or you will not get the oil pressure you need without it. I always buy a few at a time and replace this seal almost every time I remove the timing cover - they are cheap to buy.

dave M said:

Do make sure that you fit a new conical rubber oil seal on the oil pump when you fit back the timing cover, it is absent in this photo, or you will not get the oil pressure you need without it. I always buy a few at a time and replace this seal almost every time I remove the timing cover - they are cheap to buy.

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There's a seal in the timing cover which matches the nipple on the pump; it remained in the cover when I removed it.
Obviously best to refresh it. Looked up the part number...luckily some place nearby here has it.

Thanks!

It is best to secure the seal on the raised tube sticking out of the oil pump first or it may not locate properly.

I also have a G15 which I keep some distance from where I live, but in my case it's about 8,000 miles, so I can only see it and work on it once or twice a year for a short stint, however it is nearly finished and perhaps I can ride it a bit this August.

Good luck with your bike.

I know the feeling! I was in Africa for the first year I owned this bike...luckily I'll only be based six hours from it for a few years, at least when I'm not traveling further afield.

Depending on how things go, I may be able to get the bike down to where I'm living, too. I'll have the Enfield, a scooter (an old Indian Vespa copy), and the Matchless. Have to see about ease of registration for the various bikes and how many I can store and support in various locations...

That is a BEAUTY!!! Appears to be a "survivor", so it has significant value if that's the case.

In the off chance you were mulling it over without mentioning it, P11 scrambler pipes will NOT fit as a straight bolt-on, but you can cut them, re-orient the curved sections, and weld them back up to fit. The problem is the bulbous sheet metal sidecovers.

"for what it's worth"



...and, in case you didn't know it, they CAN wheelie!

grandpaul said:

That is a BEAUTY!!! Appears to be a "survivor", so it has significant value if that's the case.

In the off chance you were mulling it over without mentioning it, P11 scrambler pipes will NOT fit as a straight bolt-on, but you can cut them, re-orient the curved sections, and weld them back up to fit. The problem is the bulbous sheet metal sidecovers.

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Nice bike! And thanks...it is very much the survivor. Luckily the original owner (friend through the mountain biking community) thought I had the right attitude to inherit his bike. I didn't know anything about the model before I got it, but I had seen a P-11 and fallen for it, so this was a really good fit.

And the high pipes on the P-11 were one of the things about it that really grabbed me, but the simple G-15 style have now grown on me. That's a great job you did modifying them. Did you re-chrome them after welding, or is that jet-hot or something?

AgentX said:

That's a great job you did modifying them. Did you re-chrome them after welding, or is that jet-hot or something?

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I did the measuring and cutting, but had a more competent welder stitch the bits back together. They were then re-chromed.

grandpaul said:

AgentX said:

That's a great job you did modifying them. Did you re-chrome them after welding, or is that jet-hot or something?

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I did the measuring and cutting, but had a more competent welder stitch the bits back together. They were then re-chromed.

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The cost of re-chroming anything scares me...eventually I'll need to do something about the rims on this bike, which have big patches of peeled and damaged chrome. I think new alloys might be cheaper.

I got stainless rims for mine. My rear was $119 on ebay, labeled as an Atlas rim, but the spoke holes were too big. I realized it was a CS rim, punched for the fatter nipples on the scrambler, and snatched it up.

I got the front from Walridge for the usual price.

I cleaned up my spokes and got them re-plated. I think I spent about $120 to have every nut, bolt, washer, bracket, etc. re-plated in clear cadmium. If you take the time to clean everything, chase threads and file out nicks and wrench slips, you end up with good-as-new original bits.

Everything on those wheels is original, save for rims, rubber, bearings and seals. Most of the fasteners and brackets on the bike are original, just re-plated

Being a very late G15, it has coils, concentrics and distributor. The coils hide behind the oil tank, which is pushed outboard and inch or so from the early ones to clear the coils

http://www.ebay.com/itm/Norton-Matchles ... Vf&vxp=mtr

Used clutch pressure plate.

lazyeye6 said:

http://www.ebay.com/itm/Norton-Matchless-750-Clutch-Plate-745-/371670766648?hash=item56894dd438:g:Q5MAAOSwbYZXasVf&vxp=mtr

Used clutch pressure plate.

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Thanks for that link!

BillT, I've mentioned this before, but thank you for the detailed photos of your rebuild, they have been a big help in resurrecting my own 1967 G15 from a very incomplete rolling basket case.

Waiting on gaskets which should be here Tuesday. Decided to de-grime the engine a bit and touch up the timing, primary, and trans outer covers since there wasn't too much else to do.

Degreased and cleaned them, but the amount of scarring on them is a little beyond a quick touch-up. There are also what appear to sections where the casting has pits on the outer face, and they're not going to polish out either. (I assume? There doesn't seem to be any sign on the interior of the covers that any welding was done...assuming it came from the factory like that.) I don't intend to make the bike a showpiece, and I think I've reached my goal of simply making them look not-dirty as the bike goes back into operation.












Any input? I bought a Mother's Powerball drill buffer, but now I think taking them to an even higher luster would do nothing but highlight the scars and make it look worse. Might try using that on the hubs, though, which are very oxidized.

I would say that you have to consider the OVERALL appearance of the bike as a whole.

While I appreciate polished engine covers more than most folks, on a bike where nothing (or very little) else is polished, they distract a bit.

Slippery slope, and all that. You polish this, and that looks dull; you polish that and the other now looks sad. It never ends...

Yep, think I'll leave as-is. Just a little cleaned up. The weird spots on the covers already look too shiny compared to the blemishes. I'm sure that won't last terribly long, of course.

Only other option might be to try and scotch-brite things to a more uniform dull finish...?

@AgentX

Most scrapes and scuffs in the aluminum parts can be sanded out and polished. A power belt sander with 180 grit will take it down in a hurry, then go to 400 grit, and buff with a cloth wheel and compound.

Ditto for steel parts, however as these are usually thinner, you will have to assess whether you will break thru. If that possibility exists, build up with weld, then sand down. Of course, re-chrome or paint follows next.

Slick

Yeah, on some of the biggest scrapes on the front of the alternator hump, I'd be worried about how thinned out I'd be leaving the cover...definitely think I'd want to build it up with some weld.

That said, just to tap your experience, what about the sections of the casting which look pitted? To me, it seems the casting itself simply has defects. Any way to fix those besides grinding down beneath them, re-welding over, and grinding/polishing to shape and finish?

Anyhow, right now the priority is just getting the bike running. I'm working with an absolute minimum of tools in a driveway at the moment, and before I make any big decisions or take anything down for a true rebuild, I just want to get it on the road and feel the bike out a bit. Unlikely I'll have much time or workspace to dedicate to a big restoration over the next few years. (Moving to a small apartment, no garage, deployed a lot, etc. etc.)

AgentX said:

That said, just to tap your experience, what about the sections of the casting which look pitted? To me, it seems the casting itself simply has defects. Any way to fix those besides grinding down beneath them, re-welding over, and grinding/polishing to shape and finish?

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Lab-Metal is a body filler that contains aluminum powder. Apply as a paste, sand it down. Of course the color may not exactly match the base color of the part, but likely to be prettier than before. Lab-Metal can be powder coated.

http://www.alvinproducts.com/ProductLin ... metal.aspx

Slick

Even good (professional) aluminum welding can end up with a tiny bubble which can appear as a pock-mark when sanded down. It can also be a slightly different color than the surrounding aluminum.